Do you want to develop your career and be the best you can be? The CSIR focuses its research efforts in diverse arenas, which means that scientists, researchers and engineers have a range of multidisciplinary fields to explore. Computer scientists, for example, could find their skills applied to research efforts in anything from designing aircraft; to collecting spatial data used in town planning; to developing algorithms for controlling the behaviour of robots.
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At the CSIR, career paths are seldom linear. As scientists are exposed to so many different opportunities, many choose to grow in a whole new area of interest they had not considered before. Bio-engineer
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The Sustainable Water Resource Conference and Exhibition could not come at a more appropriate time. Water issues cannot be ignored like Electricity issues were. This event will gather together leading thinkers, academics, researchers and industry practitioners and businesses to contribute the most comprehensive, practical and innovative ideas, system designs and proposed interventions and policies on water in South Africa.
Join South Africa’s leading water sector decision makers as they engage with each other and with global and national thought leaders and policy makers on Sustainable Water Resource solutions for South Africa.
• • • • • • • • • • • •
ational and Local Government N Water Utilities Water Supply Organisations Water Research and Technology Institutions NGO’s Tertiary Education Stakeholders Water Flow and Management Product Manufacturers Water Infrastructure Suppliers New Technology Property Owners and Building Managers Investors and Financiers
Profile your solutions, products and services or fulfill your communication mandate at the Sustainable Water Resource Exhibition adjacent to the conference. Don’t miss this opportunity to participate in case-study breakout sessions, product demonstrations and networking sessions with government and industry leaders and sector professionals!
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International
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Endorsement Message
As South Africa’s custodian of our water resources, the Department of Water Affairs is actively focused on the long-term sustainability of national water resources. The Department strives to ensure that all South Africans have access to clean potable water and also actively promotes effective resource management in partnership with the sector as a whole including our sister Departments. Policy formulation, providing an oversight role, support and regulating the sector form a large part of the Department’s role and mandate and therefore we are in full support of new initiatives, research and debates that will lead our country towards a total access and sustainable usage of our water in a shot and long term basis. The Sustainable Water Resource Handbook is a publication that highlights important issues but also looks for practical solutions. Therefore as the Department of Water Affairs we fully endorse the Handbook and its objectives.
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Endorsement Message World-wide, agriculture is the largest user of water – without water there is no food. Without clean water there is no health - sick water leads to sick people through diseases as wide-ranging as diarrhoea and malaria. Water shortages can also constrain investment and economic growth. As a water scarce country in a region set to be hard-hit by climate change, water security should be at the top of the national agenda. With our water resource already close to fully subscribed, South Africa faces physical water shortages as early as 2025. Water wars are not a specter in our future, but a reality of our present day: the conflict in regions like Darfur in Southern Sudan has been ascribed by leading economist, Jeffrey Sachs, to a shortage of water aggravated by climate change. To preserve water we need to use it more efficiently and prevent wastage and pollution due to negligence or failing infrastructure. We also need to protect or restore our soils and the ecosystems that provide us with water.
Peet du Plooy The Environmental Goods and Services Forum of South Africa An Initiative of the Department of Trade and Industry
Without these urgent interventions, we put our very lives on the line. The Environmental Goods and Services Forum of South Africa promotes the development and use of products, services and technologies that will assist in halting the current path of water wastage and pollution in our country. We therefore endorse the Sustainable Water Resource Handbook and welcome its arrival.
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Endorsement Message One of government priorities is providing sufficient food to the South African public. Food security is at the same time linked to a comprehensive rural development programme (CRDP). Therefore water quality remains a priority to sustain an agricultural infrastructure and for farming to remain an economic activity. The recent economic downturn has cast challenges on food affordability as income levels dropped especially due to job loses. In response, the agricultural, forestry and fishery sector has once again occupied centre stage with its ability to create jobs and absorb a wide range of cross cutting skills. Economists have argued that these sectors have the ability of creating more jobs per R1 million investments than any other sector. Through research and innovation, food production especially at household levels is supported by smart water recycling solutions bringing relief in water densely populated areas such as Muyexe Village in the Limpopo Province. The use of veggie towers, an innovation that limit water loss in growing food was recently piloted in the village among 15 households. Here, the neighbourhood is involved in the construction of similar devices to replicate and enlarge vegetable production using grey water. The involvement of rural communities in designing these innovative models suit communal needs for the creation of sustainable economic opportunities in agro-ecology for SMMEs and cooperatives. The CRDP provides local production to replace imports to minimise the carbon footprint of the sector, where otherwise, food would be transported over large areas. Further, the Department of Agriculture, Forestry and Fisheries will facilitate the establishment of agricultural infrastructure to improve efficiency of production for all commodity value chains. This will include systematic efforts in irrigation projects in areas receiving little rainfall, to increase local food production. Furthermore, the department will have to consider the effects of agriculture on climate change and vice versa, and develop appropriate responses which would include among others, investing in cleaner production methodologies, improved water care through limited pollution as a result of pesticides, creating green job opportunities, promoting innovation and applying scientific technology in the production processes through investments in employment, economic and development opportunities to mitigate the effects of climate change. If we manage our natural resources together, we can do more and increase food security for all. the sUSTAINABLE Water Resource HANDBOOK
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• • • • • •
endorsement message The three principles of equity, sustainability and efficiency underpin the process towards achieving intergraded water resources management. As enshrined in the National Water Act, integrated water resources management is intended to enable us to meet the needs of our people for water, jobs and economic growth in a manner that also allows us to protect and, where necessary, rehabilitate our aquatic ecosystems. Above all, integrated water resources management will make it possible for us to use our precious water to assist in addressing the overwhelming need to eradicate poverty and remove inequity in South Africa. The Department of Cooperative Governance and Traditional Affairs welcomes the launch of the Sustainable Water Resource Handbook for South Africa and endorses its presence and its objectives. As a key stakeholder in the Water sector, the Department of Cooperative Governance and Traditional Affairs supports the concept of the sustainable development of the water sector in South Africa and supports all those that are playing a role in contributing towards a safer, more effective, more efficient and more sustainable environment. The Department will continue to be your partner in service delivery and development – let us make sure that we get the full value out of every drop of water.
Ongama Mahlawe Special Project Head : Infrastructure and Economic Development
Yours faithfully Mr Ongama Mahlawe
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GENERAL MANAGER Suraya Manuel
South Africa Volume 1
ACCOUNTS & ADMINISTRATION Wadoeda Brenner Ursula Thomas Rashieda Cornelius HEAD OF SALES Annie Pieters
EDITOR Gareth McConkey Dr Jac Wilsenach
ADVERTISING SALES Tafadzwa Shayawabaya, Mandy Anderson, Ruvahn Crowley, Nelmon Kanyinji, Mario Hartle
CONTRIBUTORS B Ashe, C Bosman, J Cain, J Clayton, D Dold, W Enright, M Makeka, G McConkey, J Menge, R Murray ,D Nozaic, A Roux, G Tredoux A Turton, Mvan Veelen, J Wilsenach, K Winter
CHIEF EXECUTIVE Lloyd Macfarlane
THANKS TO: Karen Marx and Garth Barnes, Katrin Gamble (WESSA North), The Finishing Post LAYOUT & DESIGN Rashied Rahbeeni
DIRECTORS Gordon Brown Andrew Fehrsen Lloyd Macfarlane PRINCIPAL FOR AFRICA & MAURITIUS Gordon Brown
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EDITORS’ NOTE
EDITORS’ NOTE Water scarcity is a South African reality. There can be no hope of sustaining food production, generating wealth and improving our nation’s quality of life … without enough water of good quality. Yet, in years to come, there could be more and more areas in desperate need of water. Ironically, other areas may see catastrophic damage as storm-water causes havoc. We need to acknowledge that water is everybody’s business. There is no doubt that we have to manage our water resources differently in the future. This we owe to our children - not only for the opportunity of appreciating its magnificence! Although water is termed a “renewable resource”, its availability is finite. We seem to be at that limit, beyond which more and more people will have to get by with less and less water. All our major cities and economic development takes place far from the main water resources. Grand inter-basin transfer schemes are already stretched to capacity. Areas that we always associated with abundant natural water have become drought stricken. Where will more water come from in future? The Sustainable Water Resource Handbook intends to bring about a better understanding of the challenges being faced in managing South Africa’s water resources. Without this understanding, we will struggle in vain to identify the solutions required for meeting the needs of people, especially the poor. The Handbook deals with a sustainable approach to water, our legislation and the way we manage water. We have looked at our water resources and what influences them and their protection. The Handbook concentrates on the domestic uses of water, because this has created and still creates many of our most immediate challenges. The management and supply of drinking water, sanitation and urban wastewater are not easy and it requires great commitment. For this reason, many of the contributions to the Handbook deal with these issues. It was Albert Einstein that said: “We can’t solve problems by using the same kind of thinking we used when we created them. We shall require a substantially new manner of thinking if mankind is to survive.” We are fortunate in this water scarce country to have so many dedicated and passionate water professionals and scientists who research and grapple with these challenges. This Handbook could not have been put together without their willingness to contribute. As Editors of this Handbook we have also grappled with the content and we hope that this publication will positively add to an open and vigorous “water debate”. This being Volume 1 in a series, we trust that it will also be an ongoing and converging debate.
Dr Jac Wilsenach Virtual Consulting Engineers
Gareth McConkey Director Jantech cc. T/A H20asis™ - Water and Sanitation Information Solutions
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Contents Section 1: Water in South Africa 17 Chapter 1 A Sustainability Approach to Water and Sanitation 27 Chapter 2 Management of Water 35 Chapter 3 The Cost of Water
Section 2: Water Resources 47 Chapter 4 Climate and Rainfall 50 Chapter 5 Surface Water 54 Chapter 6 Ground Water in South Africa 58 Chapter 7 The Sustainability Approach: Managing Water as a Flux 66 Chapter 8 Protection of Water
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Since 1994
Passionate about a centre pivot? “Passion” is precisely how we feel about our centre pivots at SENTER 360. Apart from building a functional and exceptionally strong and rigid structure, we pay great attention to the ner points, making a day-to-day difference in your life.
Structure stability
The SENTER 360 centre pivot utilises trusses made from pipe being lighter than the traditional angle iron trusses. By using pipe trusses there are two sets of trusses per span more than leading brand machines but without adding extra weight to the span. The result is an enormous gain in rigidity, strength and exceptional resistance to high wind, ensuring a longer life and having a great advantage with towable machines. Longer 4,5 m base beams, tower supports, stabilizing rods and diagonals add to the exceptional stability. The modular design concept of the SENTER 360 centre pivot started right from the original design. Pipe lengths are only 6,4 m on all possible combinations and diameters. Trusses throughout the span range are exactly the same, only adding more trusses for longer spans. Truss rods are standard throughout the range.
Innovative control panel range
The philosophy of simple modular design is also applied to our innovative control panel range. The basic panel with direct millimeter adjustment can be expanded at minimal cost through various stages of automation and communication up to fully automated versions controlled by extensive software from your computer or cell phone.
“Last sprinkler” solution
SENTER 360 centre pivots are tted as standard with the more expensive pressure regulated Senninger I-Wob sprinklers on drop pipes to ensure outstanding water distribution in most climatic conditions. The I-Wob sprinkler has a large wetting diameter and even droplet distribution in the wetted area combined with a precise engineered droplet size. The result is a much lower than average instantaneous application rate and low wind drift. This will ensure that you get the maximum amount of water in the ground with less runoff and lower evaporation loss.
Purpose made tyres
We t as standard, purpose made irrigation tyres to the SENTER 360 centre pivot. They are designed to reduce the tendency of causing deep wheel tracks as with standard tractor tyres, but to retain excellent traction.
Heavy-duty gearbox and motor
The drive train of the SENTER 360 centre pivot comprises a heavyduty UMC wheel gearbox as standard with free optional ve year warranty* driven by the UMC Power Saver centre drive motor and gearbox. Universal couplings are purpose made shock absorbing centre pivot couplings. On top of this, you should experience our welding and workmanship…but that’s a topic for another day!
One of the more irritating practical problems in centre pivot irrigation is the tendency of the last sprinkler to clog with plant or other material entering through the irrigation water. We came up with a genius but simple way to constantly keep the last sprinkler clean even during long irrigation cycles.
Tel: 018 469 1331 E-mail: info@senter360.co.za • www.senter360.co.za
* Terms and conditions apply
Contents Section 3: Use of Water 73 Chapter 9 Urban Use of Water 80 Chapter 10 Urban Drainage 86 Chapter 11 Urban Wastewater Treatment 92 Chapter 12 Small and Package Plants 98 Chapter 13 Decentralised Sanitation and Re-Use 102 Chapter 14 Source Control Approaches 107 Chapter 15 Water Supply and Sanitation in Rural Villages 115 Chapter 16 Recreational Use of Water 121 Chapter 17 Agricultural Use of Water 127 Chapter 18 Industrial Use of Water 137 Chapter 19 Mining Use of Water
Section 4: Case Studies 143 Chapter 20 Oude Molen 153 Chapter Atlantis Water Resource Management Scheme (AWRMS)
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chapter 1: A sustainability approach to water and sanitation
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chapter 1: A sustainability approach to water and sanitation
A sustainability approach to water and sanitation Dr Jac Wilsenach Virtual Consulting Engineers
The myth of “sustainable development”
Everyday we hear the terms ‘sustainability’ and ‘sustainable development’. It is written everywhere. Academics, artists, journalists, politicians and action groups use the word as if we know its meaning … But as we look around us, we’re overwhelmed by broadcasts from over the world that stir up a different meaning – a world descending into poverty and consumption, malnutrition and obesity, industrialisation, pollution and disease, droughts and floods, and conflict.
Figure 1.1: Earthrise, 29 December 1968
Just more than 40 years ago, the Apollo 8 mission brought back a photograph of earth rising over the barren land of the moon (figure 1.1). For many people, the idea of earth as a vast territory was replaced almost overnight – replaced by an image of our earth as a lonely space ship with no harbour to dock at for fresh supplies. This realisation was fundamental in much of the environmental movement’s protest to the expansive drive and implicit assumption of an infinite resource base that underlay industrial society. Already in 1972, The Club of Rome’s report ‘Limits to growth’ forecast a collapse of human civilization by the year 2100, due to three simultaneous crises, i.e. 1) overuse of farmland, 2) resources depletion and 3) intolerable pollution increases. The recommendations were for a drastic change in our production and consumption patterns, as well as for a campaign of active birth control. The Brundtland commission’s 1987 report ‘Our common future’, prepared for the United Nations, coined the term sustainable development, which was defined as: “....development that meets the the sUSTAINABLE Water Resource HANDBOOK
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needs of the present without compromising the ability of future generations to meet their own needs”. What does this mean, even if the needs of the present were known? If we consider Maslow’s model of a hierarchy of needs, where do we draw a cut-off line for needs that have been met sufficiently? The problem regarding needs in connection with ‘sustainable development’ is worked out in more detail by Levit et al. (1998). Equally important; what time horizon do we adopt in planning for ‘sustainable development’? Geologists like Salomon Kroonenberg argues this should be 1,000 years at least, but most politicians are hard pressed to consider 10 years. The validity of the Brundtland definition hasn’t been checked in over 20 years, but still everyone agrees that issues concerning People-PlanetProsperity are somehow at stake in one way or another. Yet, if any one of the these ‘pillars of sustainable development’ is overshadowed by the importance of other issues, or blown out of proportion, one gets yet another image that fits under the umbrella of ’sustainable development’. Within only 15 years after 1972, environmentalism as a counter-culture started to become part of the mainstream of global politics and was adopted by all of the world’s large corporations. Ironically, most its former power of criticism was lost. Where every oil and other multi-national company preaches ‘sustainable development’, it is hard to believe that anything really is just that. ‘Dissidents’ are therefore not readily accepted on public podia, because as Allenby (2002) points out, ’sustainable development’ has become a forbidding ideology tolerating no criticism. The value and practical meaning of ‘sustainability’ remains vague.
The reality of un-sustainability and the possibility of sustainability
All data points to the world’s population growing from 6 billion today to 8.5 billion by the year 2025. Furthermore, the spread between rural and urban populations is still more or less equal, but nearly all the future population growth is expected to be in the urban environments of developing countries. This is equivalent to building 8 new cities - of 10 million people each - every year. It is clear then that our thinking should be focussed on the sustainability of systems in the dense urban environment of the world’s poorest cities. Cities are neither made up of static structures and infrastructure, nor steady state processes, but complex dynamic systems in which technology (to organise material and energy flux) as well as human culture (flow of information, population profile, etc.) are equally important (Allenby, 2002). The life support systems of cities stretch far beyond their municipal boundaries. Staple foods, fresh water and air, raw materials and energy are largely imported. Waste and pollutants are exported. Cities are therefore closely knit together with all earth systems, and human behaviour has become an attribute of ‘natural’ systems. If engineers are to be instrumental in creating solutions to the problem of ‘un-sustainable’ cities, the challenge is to specify and continuously refine new design criteria for the world that is already an engineered system. System re-design that is based upon ‘wholesomeness’ or ‘the natural earth’, stand no chance of creating a durable life-supporting environment. The increasingly humanized world also dictates that technical prowess alone will be insufficient and dangerous in re-designing sustainable urban-earth systems. Progress in the translation of social demands to political mandates and engineering specifications first of all requires differentiation between normative and quantitative statements. Figure 1.2 illustrates a framework that helps with this tasks of appreciating culture, religion, scientific facts, speculation, technical concepts, etc. for what they are, and for determining where these inputs to the sustainability debate fit in the humanized environment:
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Figure 1.2: The sustainability tetrahedron, highlighting different “sub-environments” and their positions relative to the normative and quantitative make-up of knowledge and arguments.
The social-cultural-political environment forms the apex in figure 1.2, which is underlain by a basis of the geophysical, biological and economic environments. All goods and services have to be delivered to society from a lower base level, into which all waste products from society must also be assimilated again. With regard to the geophysical environment, Ayres et al. (1998) argued from first principles that growth must be limited, because mechanical work is irreversibly consumed in any production process (i.e. the ability to do work is not conserved). ‘Sustainability’ must therefore involve a radical dematerialization of goods and recycle of non-renewable material, driven by solar energy. Ayres (1999) developed this idea further in terms of the ‘spaceship’ economy. Given enough exergy flux from an outside system (the sun) and a variety of sufficiently large waste stockpiles relative to the fraction active in the economy and the efficiency of waste recovery, a system can (technically) be maintained indefinitely. We’re starting to get the significance of limits, and of resource scarcity, with talk of oil peak production, declining fish populations, deforestation, etc. In the biological environment, human activity has in some way or another affected the physics and chemistry of every cubic meter of air and water on earth (Allenby, 2002). The norms (e.g. effluent standards) that apply, for instance, to urban water are based on knowledge of this base environment, but are determined on a higher (socio-political) level. Consequently, these norms determine the quality that these environments will assume over time, with possible feedback to the socio-political decision mechanism. Technological systems are therefore not only socially constructed, but also society shaping (Thomas Hughes in Bijker et al., 1989). By identifying whether criteria are rather normative or quantitative, one can understand where criteria are unlikely to change over time or where they are more culturally (temporarily) determined.
Shaping the discussions on sustainability, water and sanitation
The conventional approach adopted in the design of water and wastewater systems is increasingly coming under fire. Critiques include statements like “don’t flush toilet waste with good, clean drinking water”, “internalize burdens and manage effluent streams on site”, “recycle your greywater”, “catch rainwater”, “disconnect from the grid”, and so on, and are mostly delivered from under the banner of a sustainability approach. But why would these be more sustainable than the centralized water supply, sewer collection and wastewater treatment, or other approaches? Are there some underlying criteria - or better still, metrics - that could judge or rank the relative sustainability of one technology to another? In a sense, these are not the right questions. These are mostly reactions to cure the symptoms of a greater problem, which plays out differently from one case to the next. the sUSTAINABLE Water Resource HANDBOOK
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Figure 1.3: A systems approach to sustainability (of water and sanitation services).
Figure 1.3 shows a systems approach upon which sustainability should be funded. The system is shown as a cyclical process of knowledge transactions between different nodes. It’s also important to realize that different languages are spoken at each node, even if it’s all English (and it’s not all English). The further nodes are apart, the more distinct the language differences become. This wheel wouldn’t turn unless all the nodes along the rim were properly connected. Or if it did turn initially, it wouldn’t keep on turning. Consideration of this systems approach could be helpful to clear up some misconceptions: • The stream of public complaints about “disintegrating services” should also be turned inwards. Unless the Social Demand is articulated and prioritized properly, with sufficient pressure for accountability, ensuring a sustainable service is not of general interest. If this is a true reflection of our water and sanitation services, the question turns to racial and class divisions in South Africa that mutes a strong and unified voice. As an example of what is needed, consider the Treatment Action Campaign that united South Africans across the race divide for a single cause. This is well understood in the more mature social democracies of Northern Europe. • Operation and Maintenance (the bugbear of many a system) is only possible if enabled from within an Administrative Ownership. • We live in an inherited world, where all plans already include past decisions, and Existing Infrastructure sets and determines our abilities as well as our constraints. • Understanding the Limits of Technology is far removed from the social and political arena. Many knowledge transactions are needed to get messages across. 20
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• T he availability of New and Alternative Approaches for delivery of water and sanitation services plays only a very small role in the outcome. • Future and Contingency Plans are determined equally by Limits of Technology and by its Context Within Other Systems. Although figure 1.3 is drawn in two dimensions, there are more dimensions. Consider each of the nodes in figure 1.3 to represent the apex of a sustainability tetrahedron (figure 1.2). Indeed, each of these nodes is based upon an economic, a biological and a geophysical environment (or dimension). With everything at our disposal, from technical skill to funding, and the best of technology, we fail to implement truly sustainable systems if it’s not done within a multi-dimensional systems approach.
Criteria for sustainable water and sanitation systems
The ultimate resource, according to Julian Simon (1981), is human ingenuity. If true, problems of ‘sustainability’ are then best addressed by political and economic freedom and not by restrictive conservation programmes, because necessity is the mother of invention. According to this outlook, resources are not brute facts of nature, but products of our imaginative use of the elements in nature. In this sense, resources are not; they become (de Gregori, 1987). This is already true in urban water management where wastewater is fast becoming an important resource. What more do we say about our options for a sustainable water and sanitation systems - can we at least highlight some important criteria to follow? Below are five examples of Social Demands for further consideration:
i) Ensure sufficient water of good quality
Water is a fundamental requirement for diverse sectors from industry to food security to public health. Water is limited (especially in South Africa) and resources of water must be protected against depletion, and against pollution. Waste and pollutants find pathways to water resources, via overland flow, via collection systems (sewers) and via treatment works. Known waste and pollutants include silt, pathogens, nutrients (from human excrement, and from agricultural run-off ), metals and acidity. New organic pollutants are numerous, and keep increasing every year.
ii) Recover and recycle finite nutrients found in wastewater
Phosphate and potassium are both finite elements and two of the macro-nutrients (Nitrogen: Phosphate: Potassium) in plants. Phosphate is mined at a few localised places in the world. A problem with certain phosphate rock resources is a high heavy metal content, which moved some countries to ban import of phosphate from certain areas. Once the mining of phosphates (of good quality) and potassium reaches a peak, we would be faced by a maximum rate of food production. Before phosphate reserves run too low, or quality becomes too poor for use, recovery and recycle must be established practice. Therefore, get the pilot projects going to make the initial mistakes and get the experience. (Nitrogen recovery may not be imperative, since nitrogen gas is present in abundance in the atmosphere.)
iii) Clarify the relation between energy and water
Svardal and Kroiss (2009) show that: • Solar energy received on earth is in the order of 10,000 kW/person, • Primary power consumption in developed countries is between 5 - 10 kW/person, • The total power contained in our nutrition is in the range of 0.100 kW/person, • The total average power demand of conventional municipal waste water treatment with nutrient removal is only around 0.010 kW/person. Wastewater treatment could be run energy neutral, through the production of biogas, but energy export is unlikely, and this comes at the cost of deteriorating effluent quality. Despite promises about energy from biogas, let’s forget about that (or the carbon footprint for that matter) and concentrate on producing domestic wastewater effluent of superior quality. the sUSTAINABLE Water Resource HANDBOOK
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iv) Investigate and implement source control technologies
Imagine transporting sand of different colours on the back of a truck. You’d want to keep a division between the different colours of sand, for once they got mixed the task of separation is nearly impossible. Yet, this is what we do with urban effluent – everything goes into one pipe. Instead: • High strength organic wastes can be treated on site (where biogas production is worthwhile). • Nutrient rich streams, like sludge reject water, animal manure, and source separated urine would make recovery easier, and improves effluent quality overall. • Stormwater flows intensely in high volumes for short periods and does not belong in sewers. Source control strategies extends the capacity of existing systems, and pushes the limits of technology, by using available processes and technology.
v) Maintain and build our skills and knowledge base
Institutional memory keeps the wheels of the system turning. Young blood opens up new avenues. Our skills and knowledge base is vital for sustainable water and sanitation systems. Look after your water professionals and operators.
Conclusion
The problems encountered in water and sanitation services can be explained in terms of a systems description. If the social demand for sustainability of water and sanitation can be articulated properly, it would still require a systems approach in order to succeed. Addressing the larger problems with formulas that bring symptomatic relief, would be a step backwards. References Allenby, B. R. (2002). Observations on the philosophical implications of earth systems engineering and management. Batten Institute and the Darden Graduate School of Business, University of Virginia, Virginia, USA. Ayres, R. U. (1999). The second law, the fourth law, recycling and limits to growth. Ecological Economics, 29:473.483. Ayres, R. U., Ayres, L. W., and Martinas, K. (1998). Exergy, waste accounting and life-cycle analysis. Energy, 23(5):355.363. Bijker, W., Hughes, T. P., and Pinch, T. (1989). The Social Construction of Technological Systems: New Directions in the Sociology and History of Technology. The MIT Press, USA. de Gregori, T. (1987). Resources are not, they become: An institutional theory. Journal of Economical Issues, 21(3):1243 . 1247. Levit, R., Therivel, R., and Carlton-Smith, J. (1998). Sustainability. Paper prepared as background to the Study on Energy and the Environment, Royal Commission Environmental Pollution, (http://www.rcep.org.uk). Simon, J. (1981). The Ultimate Resource. Princeton University Press, Princeton, NJ, USA. Svardal, K. and Kroiss, H. (2009) Energy requirements for waste water treatment IWA Conference on Water and Energy, Copenhagen.
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Government BRINGS WATER AND DIGNITY TO MAQUASSI HILLS It has long been a goal of the South African government to eradicate the bucket system, and to provide clean water to as many citizens as possible. In this regard, former President Thabo Mbeki had committed his administration to eradicating the bucket system by 2007, but it continues to be the primary method of dealing with human waste in many under-developed, under-serviced, rural areas, such as townships and informal settlements. There are a number of reasons the bucket system remains difficult to eradicate: the growing population in many developing areas due to the influx of people from poorer outlying regions; lack of funding and where funding is available, lack of capacity; lack of political will; and finally, lack of engineering capability. NEP Consulting, a civil engineering consultancy based at the Bona Bona private reserve 50km south of Klerksdorp, confronted the challenge of the bucket system back in 2006, and has ensured its eradication from the Maquassi Hills Local Municipality in the North West province. On completion of the project, 4 767 households had been freed from the foul yoke of the bucket system, and the foundation had been laid for the delivery of bulk water to the area. In all, 15 000 households today have access to clean running water, with the project completed in April 2009.
The Leeudoringstad reservoir which supplies water to the Maquassi Hills Local Municipality.
profile
We have water! NEP Consulting’s Pieter Ernstat the Leeudoringstad reservoir
Maquassi Hills embraces the areas of Leeudoringstad, Wolmaransstad, Makwassie, Witpoort and Lebaleng. In Leeudoringstad 1 100 households have had the bucket system eradicated, in Wolmaranstad 3 066 and in Lebaleng 601. It is accurate to say that due to the efforts of all involved, the bucket system in the region is a thing of the past. The projects helped create a total of 438 jobs, and entailed the coordination of several entities, among them the Development Bank of South Africa (DBSA), which funded the projects; Sedibeng Water; the North West provincial government; Dr Kenneth Kaunda District Municipality; Ultimate Dynamics; and the Department of Water Affairs, to name a few. Sedibeng Water came to the table with the best price of R2,27 per kilolitre, a tariff no other supplier could match, and which was in essence at cost price. Beforehand, the area had made do with groundwater drawn from a number of boreholes. As long ago as 1995, it had been accepted that the area could not depend on this approach, and Sedibeng Water reviewed its various facilities and decided on the Balkfontein Dam as the water supplier. Today water is abstracted from the Vaal River and purified at Balkfontein before being pumped through a 250mm steel pipe over 37km to a balancing reservoir at Leeudoringstad. From there, water is pumped to the Buisfontein reservoir near Wolmaransstad over a distance of 19km. Water flow gravitates from Buisfontein to Wolmaransstad and Makwassie through a set of PVC pipes, which were recently constructed and should cope with water demand up to 2030.
profile
Maquassi Hills Local Municipality Mayor KarelLehloo.
Mr M.Mapholi Director Engineering Services and PMU manager
Mr L Ralekgetho Municipal Manager - M Dev
In addition, the local boreholes are being used to buttress local demand, but as their yield is tapering off, it has been decided to reduce supply so as to give the wellfield a rest and allow it to recover. “Today is one of the most memorable moments that will go down in the history of Maquassi Hills Local Municipality as we will be launching our projects from bucket eradication which we were the first to implement in North West, to bulk water supply which will provide services to all the people who live here for the next 15 to 20 years,” said Mayor Karel Lehloo. “Quality water and sanitation means dignity to people,” said NEP’s Pieter Ernst, a consulting engineer with more than four decades’ experience, at the launch of the Bulk Water Augmentation Programme. “We were proud, with our partners, to have brought the project in on time and within budget.” But Mr Mapholi had some cautionary words: “Government provided millions of rand to bring development to this area, and if the community is not going to look after it and pay for services that are rendered to them by the municipality, the infrastructure is not going to receive preventative maintenance, which means that it will not last for long. “The government of today has spent a lot of money towards infrastructure development throughout the whole country, and as a professional engineer and ratepayer I urge government to budget for maintenance during the implementation process and after completion by capable, highly skilled professional people that are available, and training of existing staff in respect of operation and maintenance of this infrastructure.” Contact details: MAQUASSI HILLS LOCAL MUNICIPALITY 19A KRUGER STREET P O BOX 3 WOLMARANSSTAD 2630 QUERIES : DIRECTOR ENGINEERING SERVICES AND PMU MANAGER Mr M Mapholi Tel (018) 596 1067 Fax (018) 596 2068
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Management of Water Willie Enright, Pr.Eng, Water Management Consultant, Wateright Consulting cc
Water perspective
South Africa is largely a semi-arid country with a highly varied climate. Surface water resources are already well developed although the same attention was not always bestowed on groundwater and the aquatic needs of the environment. The distribution of South Africa’s water to its cumulative population is even more unequal when measured in terms of class, race and gender. This makes it essential to manage water in an integrated manner. The Constitution of South Africa (Constitution, 1996) allocates responsibility for specific functions between the different spheres of government at national, provincial and local level. The National Department of Water Affairs is to act as the custodian of water as a public resource and ensure that it be managed for the optimal benefit of society as a whole. Local government is responsible for the provision of water services while national government has a regulatory and supportive function. As part of the Bill of Rights, the Constitution guarantees everyone the right to have the environment protected while promoting justifiable economic and social development, the right to access to sufficient food and water and the right to dignity. The political transition in South Africa created a unique opportunity with the required political will to effect new legislation to address integration of water resource management in terms of quantity and quality, surface and ground water, with a strong emphasis on equity and sustainability with efficiency as a key part to that. The water law reform process developed key principles through a wide public participation process before it was entrenched in the National Water Act in 1998. Chapter 1 of the National Water Act (Act 36 of 1998) sets out the fundamental principles and states “Sustainability and equity are identified as central guiding principles in the protection, use, development, conservation, management and control of water resources. “These guiding principles recognise the basic human needs of present and future generations, the need to protect water resources, the need to share some water resources with other countries, the need to promote social and economic development through the use of water and the need to establish suitable institutions in order to achieve the purpose of the Act.”
Integrated Water Resource Management
The National Water Act incorporates international principles of Integrated Water Resource Management (IWRM). The National Water Resource Strategy (NWRS) (DWAF, 2004) defines IWRM “as a process which promotes the co-ordinated development and management of water, land and related resources in order to maximise the resultant economic and social welfare in an equitable manner without compromising the sustainability of vital ecosystems”. Meeting basic needs and ensuring sustainability of the environment are key principles, as well as developing human resources and building the economy through involvement of all water users and stakeholders. Water resource management is an important tool to build a socially and environmentally just society. Everyone in the country is required – and should be enabled – to play an active part in water management. The Act has substantially altered the framework for access to water, ensuring the improved and equitable distribution of this precious resource. Ecological requirements and basic human needs are given high priority. The concept of private water is abolished and groundwater is managed as part of the integrated water cycle. Access to water is divorced from land ownership. Water resource management should be a multi-disciplinary exercise involving all sectors of society to make sure that the purpose of National Water Act (NWA, 1998) is adhered to by ensuring that the the sUSTAINABLE Water Resource HANDBOOK
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nation’s water resources are protected, used, developed, conserved, managed and controlled in ways which take into account other factors: • Meeting the basic human needs of present and future generations • Promoting equitable access to water • Redressing the results of past racial and gender discrimination • Promoting the efficient, sustainable and beneficial use of water in the public interest • Facilitating social and economic development • Providing for growing demand for water use • Protecting aquatic and associated ecosystems and their biological diversity • Reducing and preventing pollution and degradation of water resources • Meeting international obligations • Promoting dam safety • Managing floods and droughts The National Water Act provides the framework for managing this precious resource in all aspects together with all stakeholders.
Water use management
A person can be entitled to use water only if the use is permissible under the National Water Act. The basis for regulating water use is therefore of central significance to the Act. Water use is extensively extended from the previous Water Act and relates to the consumption of water as well as to activities that may affect water quality and the condition of the resource itself. The following uses are included in Section 21 of the National Water Act (NWA 1998) to be authorised: • Taking water from a water resource • Storing water • Impeding or diverting the flow of water in a watercourse • Engaging in a stream flow reduction activity contemplated in section 36 (Commercial forestry) • Engaging in a controlled activity identified as such in section 37(1) (e.g. irrigation of land with waste or water containing waste generated through any industrial activity or by a waterwork) or declared under section 38(1) • Discharging waste or water containing waste into a water resource through a pipe, canal, sewer, sea outfall or other conduit • Disposing of waste in a manner which may detrimentally impact on a water resource • Disposing in any manner of water which contains waste from, or which has been heated in, any industrial or power generation process • Altering the bed, banks, course or characteristics of a watercourse • Removing, discharging or disposing of water found underground if it is necessary for the efficient continuation of an activity or for the safety of people • Using water for recreational purposes In general, a water use must be licensed unless it is listed in Schedule I (permissible use of water) (NWA1998), is an existing lawful use, is permissible under a general authorisation, or if a responsible authority waives the need for a licence. Water use will eventually all be controlled through time-limited general authorisations and licences with relevant features such as effective periods, purposes and places for which it may be issued. Specific conditions may be attached to it. The granting of a licence does not imply any guarantee regarding the availability or quality of water which it covers. Use of water by existing users will have to be verified to quantify existing lawful use and relevant conditions related to that. Compliance and enforcement to ensure that water use is correctly utilised needs to be more stringent. Over abstraction of water needs to be curtailed. Where disputes arise between any persons relating to any matter contemplated in the National Water Act, the Minister can direct that the persons concerned attempt to settle their dispute through a process of mediation and negotiation. 28
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The water allocation reform process ensures redress in terms of race and gender with respect to access to water use, promotes poverty alleviation initiatives, supports economic growth, provides opportunities for job creation and promotes sustainable and efficient water use. Existing use will be curtailed where necessary to ensure efficiency, requirements for the ecological functioning for sustainability of rivers and for equitable reallocation of water to historically disadvantaged groups. New licences for available water in a river system must, as a first option, be granted to black economic empowerment. The challenges for future water resource management are huge. Each sector needs to take note of developments in water resource management and prepare for increased management implications. The correct water management institutions need to be in place, monitoring and information systems available to be able to address challenges of water scarcity, floods, climate change, and allocation and control of water. The National Water Resources Strategy and individual Catchment Management Strategies for the relevant Water Management Areas need to address these challenges.
National Water Resource Strategy
The Act requires the development of a National Water Resource Strategy (NWRS) by the Minister. This Strategy provides the framework for the protection, use, development, conservation, management and control of water resources for the country as a whole. It also provides the framework within which water will be managed at regional or catchment level in defined water management areas. The NWRS must be formally reviewed from time to time. The NWRS (DWAF, 2004) outlines the goals and objectives of water resources management for the country and sets out the strategies, plans and procedures to achieve these goals. It identifies opportunities for social and economic development where water is available. Greater integration will be required in all the major functional areas of water resources protection, allocation and conservation. Infrastructure development, water demand management and water quality management should be harnessed together in order that water is used in the most beneficial and efficient way. Some of these measures are already being implemented including the determination of ecological flow requirements before authorising any other new water use. Verification of existing lawful uses needs to be done in all areas and compulsory licences will ensure a redistribution of water use to ensure equitable, efficient and sustainable water use.
Catchment Management Strategies
The Act requires that a Catchment Management Strategy (CMS) must be developed for each of the Water Management Areas and states: “A catchment management strategy is the framework for water resources management in a water management area. The NWRS provides the framework within which all catchment management strategies will be prepared and implemented in a manner that is consistent throughout the country.� The development of a CMS is an initial function of a CMA and must therefore be done at an early stage. The catchment management strategy can be developed and reviewed in phases, taking into account further information as and when it becomes available, e.g. extent of water uses, reserve determination, etc (DWAF, 2007). In the process of developing this strategy, a CMA must seek co operation and agreement on water related matters from the various stakeholders and interested persons. Principles must be set for allocating water to existing and prospective users, taking into account all matters relevant to the protection, use, development, conservation, management and control of water resources.
Water Management Institutions
The National Water Act enables the realisation of the goal of democratisation of water resources management. In this regard the Act provides for the devolution of powers to manage the water resources. A vehicle for the devolution of these powers is the establishment of suitable water management institutions. Water management institutions thus need to demonstrate democratisation and should have appropriate community, racial and gender representation. This prerequisite entrenches the need to have all sectors of society involved in the management of water resources (DWAF, 2004). the sUSTAINABLE Water Resource HANDBOOK
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Due to the fact that water does not recognise political boundaries it is important that management of water resources should be carried out in regional or catchment water management areas that coincide either with natural river catchments or groups of catchments. The Department of Water Affairs will, once the water management institutions have been established, be responsible for national level policy and strategy development, planning, international negotiations on water sharing, development and monitoring of the National Water Resource Strategy, and oversight and regulation of water management institutions.
Catchment Management Agencies
The need for integrated management of water resources on a catchment basis to support sustainable development has been adopted as a key principle. The vision for the establishment of Catchment Management Agencies (CMA) is to create an institution for decentralised water resources management (WRM) decision making, to reflect local requirements and interests. The country is divided into 19 water management areas (WMA). CMAs responsible for water management will eventually be established to manage water in these water management areas (NWRS, 2004). Although it was originally envisaged that 19 CMAs would be established, a study into the alignment of water management institutions, currently recommends that approximately 9 CMAs be established. This will lead to strengthening accountability of the various institutions; ensuring integration, cohesion and coordination of water resources functions and strengthen sectoral partnerships while optimising the available capacity (Enright, 2008). The specific water resources and issues in respective water management areas will affect the responsiveness and needs of stakeholders and thus the key performance indicators of the respective CMAs.
Figure 2.1: Water Management Areas of South Africa
CMAs are agencies of government, carrying out the mandate and imperatives of national government but functioning at the catchment level. CMAs must be developmental in nature. Being a public entity it is important to exercise good corporate governance with strict financial discipline, independent auditing, governance systems, procedures and controls, sound human resource management while ensuring technical ability and engagement with stakeholders. CMAs will be developmental in nature, and serve the interests of equity, corrective action and optimum use of water. Any functions carried out by a CMA would be done within the parameters of national policy and standards. The governance structure of CMAs will balance the requirement to 30
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reflect the interests of various stakeholders with the need to ensure the effective management of the catchment area. The CMA will be established in an environment where various institutions already exist. The CMA should recognise these institutions and obtain a good understanding of their role and function in the area to obtain legitimacy. The functions to be performed under the control of the CMA lean strongly on the principle that the CMA must work together with existing and transformed institutions in the water management area. Adequate skills and capacity must be developed in the WMA to accept the full range of functions over a short period of time, while the extent of performance should be intensified as further capacity is built. The social and economic development responsibility of the CMA in the process of democratisation of water management is important. They must promote and ensure efficient water use in terms of taking, storing, quality, information and data acquisition, water reallocation and black economic empowerment and promoting access to water by the historically disadvantaged groups. Capacity building of stakeholders to enhance the ability to understand water resource management issues and to develop skills in the management of water resources must get adequate attention. The indicators for success of the CMA are whether adequate water is available for communities to meet their needs, the resource is not over-allocated or over-utilised, users receive water of an adequate quality and stakeholders are water-wise and participate effectively. The CMA must be perceived to be credible and effective, must make significant progress towards poverty eradication and economic growth and must sustain a high level of service delivery to its stakeholders.
Water User Associations
Water User Associations (WUA) are co-operative associations of water users who undertake waterrelated activities at a local level. WUAs are statutory bodies that can coordinate drawing up a catchment management plan and strategy for the river and local catchment area. WUA can perform water control functions as well as billing of water resource management charges on behalf of the catchment management agency. All existing irrigation boards must be transformed into water user associations that are representative in terms of race and gender. By changing the focus from management of mainly irrigation water use by riparian property owners to management of all water uses and users in catchments, representivity of management committees and involvement by all in water management can be achieved. This transformation imperative can support the broad objectives of the National Water Act to also reallocate water entitlements to historically disadvantaged groups. Key benefits of WUA to water resources management (Enright, 2008) include: • The self regulation of water use activities • The monitoring of water resources status and use on site. • Management of water use and conflicts between users during periods of shortage in a fair and equitable way through water management plans • Resource protection, pollution prevention and conservation. This directly supports the goals of sustainable resource development. Potential problems can be prevented before they occur thus saving considerable time and cost in terms of clean up and other emergency measures • Provision of a mechanism whereby users of the resource can be directly involved with the management of the resource be able to take decisions that affect their own lives. This is in line with the principle of devolution of powers and functions and allows people to build capacity in water management and ensuring democratisation of water management on local level The challenge is to fast-track the transformation of irrigation boards into water user associations to be fully representative of all water uses and users. The focus must change from maintenance of water works only to real water resource management and reallocation of water. These institutions can actively support and implement the catchment management strategies on local level.
Water Tribunal
The Water Tribunal is an independent body with a mandate to hear and adjudicate appeals on a wide range of water-related issues, mainly against administrative decisions made by responsible authorities the sUSTAINABLE Water Resource HANDBOOK
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and water management institutions such as decisions on licences to use water and appeals against directives to remedy or prevent pollution (NWA, 1998). It will also adjudicate claims for compensation where a user considers that the economic viability of her or his water-use activity has been severely prejudiced by a refusal to grant a licence, or a reduction in water use when a licence is granted or reviewed. The Tribunal may hold hearings in the areas where the cause of action arose.
Monitoring and Information
The availability of reliable data and information on all aspects of water resources management is fundamental to the successful implementation of water resource management. Proper decisions can be made only on reliable, relevant and up-to-date information. Information for decision-making should reflect the integrated nature of water resources, in which the quantity and quality of surface and ground water are all interrelated. References Enright WD (2008) Challenges in water resource management in the future. 11th International Winelands Conference 2008, Stellenbosch, 16-18 April, 2008 Department of Water Affairs and Forestry (DWAF, 2007). Guidelines for Catchment management Strategies: Towards equity, efficiency and sustainability in water resources management. By S.R. Pollard, D. du Toit, Y. Reddy and T. Tlou. Department of Water Affairs and Forestry, Pretoria, South Africa. Department of Water Affairs and Forestry (DWAF, 2004), National Water Resource Strategy, First Edition - September 2004 South Africa (Republic). 1996. Constitution of the Republic of South Africa Act, 1996 (Act 108 of 1996), (Constitution 1996). Pretoria: Government Printer. South Africa (Republic). 1998. National Water Act, 1998 (Act 36 of 1998),(NWA 1998). Government Gazette, Vol. 398, No 18182, 26 August 1998, Cape Town: Government Printer.
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profile
Grinaker-LTA As the scarcity of clean water becomes of increasing concern around the world, South Africa is also faced with the impact of wide-ranging droughts and the challenge of providing every citizen with access to clean water every day. At the same time, pressure is mounting on industrial and mining companies to limit their water consumption and eliminate discharges in their waste water. Grinaker-LTA is a multi-disciplinary construction and engineering group, whose origins date back more than 100 years. Our capability includes building, civil engineering, concessions, mechanical & electrical, earthworks engineering and mining and we have a solid track record of successfully delivering large and complex projects. We have the capability to design and build a broad range of water related infrastructure, both with cross sector capability as well as by partnering with our associated companies in The Aveng Group. In 2007, Grinaker-LTA completed its contract on the multi award winning Berg River Dam project near Franschhoek, Western Cape. The construction team moved some 3.1 million m3 of earth to build the dam which has a gross storage capacity of 130 million m3, significantly increasing Cape Town’s total water supply. The multi award winning Berg River Project in Franschhoek, Western Cape
We are also increasingly assisting our clients to minimise their water consumption to limit climate change with our green products and services. For example, we designed dry cooling natural draft cooling towers on a current power station project to reduce our clients’ water usage. We also deployed water wise infrastructure in several commercial construction projects in the last two years. Contact: Doreen Du Plessis Tel: 011 578 6000 Email: dduplessis@grinaker-lta.com www.grinaker-lta.com
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Cost of Water Willie Enright, Pr.Eng, Water Management Consultant, Wateright Consulting cc
Guiding principles
The review of the water law was guided through a wide public participation process, culminating in a set of basic principles. These principles were embodied in the White Paper on National Water Policy, 1997, as a statement of Policy and followed up by enacting it in legislation with the Water Services Act, 1997 (WSA, 1997), and the National Water Act, 1998 (NWA, 1998). The National Water Act (Act 36 of 1998) states that “sustainability and equity are identified as central guiding principles in the protection, use, development, conservation, management and control of water resources.” Some of the basic principles are that beneficiaries of the water management system shall contribute to the cost of its establishment and maintenance on an equitable basis and that water management institutions shall be self-driven and financially viable. Three fundamental objectives for managing South Africa’s water resources arise from these principles (NWRS, 2005): • To achieve equitable access to water, including access to water services, to the use of water resources, and to the benefits from the use of water resources. • To achieve sustainable use of water, by making progressive adjustments to water use to achieve a balance between water availability and legitimate water requirements, and by implementing measures to protect water resources. • To achieve efficient and effective water use for optimum social and economic benefit. The charges for the use of raw water and potable water in South Africa are largely based on the user pays principle. The price of water is based on the actual cost of delivering all services from catchment and resource management through to infrastructure development and operation, the purification and distribution of water and treatment and discharge of waste water. This results again in the management cost of the resource to ensure protection and sustainable use. This approach contributes to achieve equity and sustainability in water matters by promoting financial sustainability and economic efficiency in water use. The real financial costs of managing water resources and supplying water, including the cost of capital, must eventually be recovered from users (NWRS, 2005).
The NWA, 1998, provides for three types of water use charges for:
− Funding water resource management: Activities such as information gathering, monitoring and controlling water resources and their use, water resource protection (including waste discharge and the protection of the Reserve), and water conservation. − Funding water resource development and use of waterworks: The costs of investigation, planning, design, construction, operation and maintenance of waterworks, pre-financing of development, a return on assets, and the costs of water distribution. − Achieving the equitable and efficient allocation of water: Economic incentives to encourage more efficient use of water, water conservation, and a shift from lower to higher value uses. The latest Pricing Strategy for raw water was published in the Government Gazette on 16 March 2007 (DWAF, 2007). The charges may be different for each user sector, depending on the costs of and the sUSTAINABLE Water Resource HANDBOOK
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benefits from water resource management services, or from the use of a particular supply scheme. These charges are done in terms of the Pricing Strategy and therefore constitute a charge upon the land. Any new landowner becomes liable for the current and outstanding charges on water use.
Funding Water Resource Management
The cost of management of water starts with the functions of protection, conservation, management and control of water resources. It is important that the sources such as rivers, groundwater, wetlands and estuaries are well looked after. The Department of Water Affairs is the custodian of all water resources. The NWA, 1998, makes provision for the devolution of powers to local water management institutions to manage the water resources. The country is currently divided into 19 water management areas (WMA). Catchment Management Agencies (CMAs) responsible for water management will eventually be established to manage water in these water management areas (NWRS, 2004). Water resource management charges are being levied to cover the cost of water management in a particular water management area. These charges will therefore be used to fund the management functions of catchment management agencies when established to cover the cost of their functions and to ensure their viability.
Water Resource Management Charges
The water resource management charges are directly related to the cost to regulate, manage and maintain water resources in the catchments of the particular water management areas. These charges will be based on the budgeted annual costs of the following activities that will eventually become the responsibility of catchment management agencies:• Planning and implementing catchment management strategies. • Monitoring and assessment of water resource availability and use, and resource quality. • Management of water allocation and utilisation. • Water quality management, including waste control and pollution control in respect of mines, industries, agriculture and dense settlements. • Dam safety control. • Water conservation and demand management. • Part of the programme for the control of invasive alien vegetation under the Working for Water Programme, and control of aquatic weeds. Some of the management costs and initial setting up costs of the CMAs will not be funded through water use charges but directly from the Department of Water Affairs. These include the cost of planning studies, monitoring and information for national purposes, and preparing preliminary / interim catchment management strategies prior to the establishment of an agency. The first Catchment Management Strategy of the CMA will also be funded from the Department of Water Affairs. Costs related to poverty relief activities in the control of invasive alien vegetation, which do not directly contribute to improving water availability, are excluded from the charge. Water resource management charges will not include costs related to waste discharge, or the capital costs of abandoned mine rehabilitation, until the waste discharge charge system is implemented. Charges are based on the registered volumes for taking of water and stream flow reduction activities (commercial forestry). For inter-basin transfers, the loss of income to the donor CMA will be funded by water use charges raised in the receiver WMA. Although it was originally envisaged that 19 CMAs would be established, a study into the alignment of water management institutions, currently recommends that approximately 9 CMAs be established. This should contribute also to the better utilisation of resources and in cost effectiveness.
Charges for funding water resource development and the use of waterworks
Differential charges will be imposed on users of water from government water schemes and systems, 36
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and from schemes funded by other water management institutions (water user associations). This charge is based on the consumptive use from schemes.
Government Water Schemes
Users of water from specific Government water schemes will pay all the direct scheme-related operation and maintenance costs, plus an equitable portion of the indirect, non-scheme-specific costs related to managing all the waterworks in the region. Charges for water resource development on government water schemes are based on a 4 percent return on the depreciated replacement value of assets, as well as an annual depreciation cost. Allowing for a return on assets in water use charges will make provision for funding new developments. The provision for asset depreciation will fund the refurbishment of infrastructure at the end of the useful life of major components of the scheme. Charges will be phased in progressively over time to achieve the target of full cost recovery.
Water user associations
Charges set by catchment management agencies and water user associations must make provision for the full recovery of capital costs (including the costs of servicing loans), depreciation of assets, water resource management, operation and maintenance and associated overheads (DWAF, 2007). Financial assistance to emerging farmers are available on water use charges for water provided from government water schemes and water user associations in a decreasingly subsidised method over a period of five years.
Charges by Water services authorities for potable water
District municipalities or local municipalities are acting as Water Services authorities and are responsible for the purification and distribution of potable water. Charges to the consumers are therefore determined by them within boundaries of national guidelines, norms and standards. A tariff set by a water services institution for the supply of water through a water services work or consumer installation designed to provide an uncontrolled volume of water to a household must include a volume based charge that – (a) supports the viability and sustainability of water supply services to the poor; (b) discourages wasteful or inefficient water use; and (c) takes into account the incremental cost that would be incurred to increase the capacity of the water supply infrastructure to meet an incremental growth in demand. A block rate tariff structure is required for municipal water use with the lowest block to ensure free basic water – especially for the poor. The highest consumption block must be set at an amount that would discourage high water use and that reflects the incremental cost that would be incurred to increase the capacity of the water supply. A water services institution should make every effort to supply the basic water supply quantity of six kilolitres per household per month free of charge. It would be the norm for users supplied out of standpipes and by means of controlled volume supplies to use no more than a basic supply. These users will generally be representative of lower income groups.
Waste Discharge Charge
The Department of Water Affairs developed a Waste Discharge Charge System (WDCS) to promote waste reduction and efficient water use (DWAF, 2006). It forms part of the Pricing Strategy and is being established under the National Water Act (Act 36 of 1998). It is based on the polluter-pays principle and aims to: • Promote the sustainable development and efficient use of water resources • Promote the internalisation of environmental costs by impactors • Create financial incentives for dischargers to reduce waste and use water resources in a more optimal way • Recover the costs of mitigating the impacts of waste discharge on water quality. the sUSTAINABLE Water Resource HANDBOOK
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We mitigate our impact on the environment
Indigenous plants are removed from wetland areas prior to topsoil removal and then planted in bulb beds for future replanting.
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The basis of the polluter pays principle is that the costs of environmental impact should be borne by those responsible for the impact. The South African Constitution, 1996, through the Bill of Rights, provides the right to an environment that is not harmful to health or well-being, and that is protected for the benefit of present and future generations. These rights are to be ensured through measures that prevent pollution and ecological degradation. The waste discharges will be based on load discharged. It avoids dischargers diluting their effluent to achieve cost reduction. This does not disproportionately penalise small dischargers with relatively higher effluent and is simple to implement. The waste discharge charge is introduced to address the problem of excessive water pollution. It will also support the following additional objectives: • To encourage efficient resource utilisation (incentive objective) • To recover costs of activities aimed at pollution abatement and damage caused by pollution (financial objective) • To discourage excessive pollution (deterrent objective) • To promote sustainable water use (social objective) Users engaging in a waste discharge related water use defined in terms of section 21 of the National Water Act, 1998, must register the use with the Department of Water Affairs. These uses relate to irrigating with wastewater, discharging waste or water containing waste into a water resource, disposing waste or water containing waste into a land-based facility, disposing heated effluent, marine discharges and removing water found underground. There are two waste discharge charges, namely an Incentive Charge and a Mitigation Charge (DWAF, 2006). The Incentive Charge is for the use of the resource rather than for recovering costs. It seeks to change discharge behaviour. It is thus an environmental tax, which requires the promulgation of a Money Bill in terms of National Treasury’s environmental tax policy. Surplus incentive charge revenue could be used to provide seed funding to users in the catchment from which it originated to enable them to undertake capital expenditure for load reduction. The principle of the incentive charge is that it should be set at the minimum level that will serve as an incentive to dischargers to reduce their effluent loads at source, so that the cumulative effect in the catchment will such that the resource quality objectives are met. It will be based on monitored discharge load, given that it seeks to change actual discharge load. The Mitigation Charge is intended to cover the costs of mitigation measures undertaken in the water resource and will be applied in cases where it is more economically efficient than the costs of reducing discharge load at source. There are four categories of Mitigation Charge: • Mitigation through removal of load from the resource, including a regional mitigation scheme or infrastructure or a regional mitigation project • Water resource system operation for the dilution, blending or purging of poor quality water • Mitigation for treatment costs downstream • Treatment at source, in order to apply the most cost-effective treatment options to a limited number of dischargers in a catchment Waste discharge charges will be introduced in a phased approach from 2010.
Water Research Levy
The mandate of the Water Research Commission (WRC) is to promote coordination, cooperation and communication in the area of water research and development as well as stimulating funding for and carrying out water research. The Water Research Commission is funded through the Water Research Fund which derives income from levies on water consumption. The funds are collected for the WRC by the Department of Water Affairs. the sUSTAINABLE Water Resource HANDBOOK
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Challenges
The increasing scarcity of clean water has emerged as one of the most pressing challenges of the future. The management of the whole water cycle from catchment management and water use control, through infrastructure development and operation, purification and distribution, waste discharge management and back to resource protection add to the cost of water. A number of stakeholders and institutions are involved in the whole water succession of required activities. Better management and rehabilitation of water resources and water infrastructure is required, whilst uncertainties such as the effect of climate change must be factored in. An integrated and coordinated approach and commitments from all sectors are required to ensure that the precious resource of water is well managed at an affordable price to the users whilst catering for the environmental and social needs. References Department of Water Affairs and Forestry (DWAF, 2007), Establishment of a pricing strategy for water use charges in terms of Section 56(1) of the National Water Act, 1998. Government Gazette 20615, Notice 1353, 12 November 1999, Cape Town, Government Printer. Department of Water Affairs and Forestry (DWAF, 2006). Strategy for the Waste Discharge Charge System, Version 1.9, Oct 2006. Pretoria DWAF Department of Water Affairs and Forestry (DWAF, 2004), National Water Resource Strategy, First Edition - September 2004 Department of Water Affairs and Forestry (DWAF, 2002), Guidelines for compulsory national standards and norms and standards for water services tariffs, April 2002, Pretoria South Africa (Republic). 1998. National Water Act, 1998 (Act 36 of 1998), (NWA, 1998). Government Gazette, Vol. 398, No 18182, 26 August 1998, Cape Town, Government Printer. South Africa (Republic). 1997. Water Services Act, 1997 (Act 108 of 1997), (WSA, 1997). Government Gazette, Vol. 398, No 18522, 19 December 1997, Cape Town, Government Printer. Department of Water Affairs and Forestry, 1997. Fundamental Principles and Objectives for a New Water Law in South Africa, 1997.Pretoria. DWAF. South Africa (Republic). 1996. Constitution of the Republic of South Africa Act, 1996 (Act 108 of 1996), (Constitution, 1996). Pretoria: Government Printer.
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Department of Water affairs (DWA) & African Ministers’ Council on Water (AMCOW) Since its inception in 2002, the African Minister’s Council on Water (AMCOW) has developed into a credible institutional mechanism for high-level policy coordination, political leadership, and advocacy for the development, protection, management, and judicious use of Africa’s water resources. As part of the new leadership of AMCOW, The South African Department of Water Affairs (DWA) seeks to carefully assess the achievements of the past seven years, explore ways to consolidate and upscale them and to identify the challenges that continue to hinder progress towards in achieving the African Water Vision 2025 of “an Africa where there is an equitable and sustainable use and management of water resources for poverty alleviation, socio-economic development, regional cooperation, and the environment.” Africa’s water crisis and policy challenges are now broadly recognised as central to the continent’s development agenda. Indeed the situation is dire with approximately 340 million Africans still lacking access to safe drinking water and 580 million are without basic sanitation. These startling figures reflect Africa’s continuing struggle on its path towards achieving the water-related Millennium Development Goals (MDGs). It is evident that appropriate policy, legal, and institutional frameworks are lacking while technical capacity remains low. African Heads of State have at the highest level demonstrated political commitment to the development of the water and sanitation sectors and meeting the MDG targets and realising the Africa Water Vision 2025. The political will generated through these processes provides a critical basis for ensuring that the necessary resources are allocated to see these commitments through. • In February 2008. the eThekwini Declaration raised the profile of the formerly neglected issues of sanitation and hygiene • In March 2008 the Tunis Ministerial Declaration on “Accelerating Water Security for Africa’s Socio-Economic Development” focused on strengthening partnerships for regional and national actions to improve water security throughout the continent • The July 2008 Ordinary Session of the African Union, the African Heads of State and Government turned their focus to recognizing the central importance of water and sanitation for the continent’s social, economic, and environmental development, resulting in the Sharm el Sheik Declaration enunciates the highest level of political commitment. • In December of 2008, the Ministerial Conference on Water for Agriculture and Energy in Africa held in Sirte, Libya. The Sirte Declaration reaffirmed the commitment of African countries to adopting and implementing sound policies, institutional reforms and financial investments to support water development aimed at improving the agriculture and energy sectors.
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These events and actions have increased awareness of water security and sanitation issues, notably water for growth and development, the achievement for water and sanitation targets in the Africa Water Vision 2025 and the Millennium Development Goals, Impact of Climate Change and Variability on Water Resources, Food Security, Financing, Africa Water Infrastructure as well as the need for improved regional cooperation on Water Resources Management. In February 2009, in preparation for the 5th World Water Forum, an African regional Position Paper was developed to shift from the policies of ‘what and what not’ to aim for the practicalities and realities of the ‘how and ‘who’ of implementing the Africa Water Vision. Indeed as stated in the position paper then, “Africa has now reached the point where there needs to be a greater convergence between the high level commitments and delivery through concrete and unambiguous actions, strengthening and scaling-up of existing mechanisms and initiatives, and refinement of strategies to close the gaps.” AMCOW makes the following decisions as follow-up to the implementation of the Sharm El-Sheikh Commitments on Water and Sanitation made by our Heads of State in July 2008: • The document “Delivering on Africa’s Water Security Commitments: A Framework for Reporting Actions to the African Union” is adopted as the Roadmap for the Implementation of the Sharm El-Sheikh Commitment • Countries should internalise the actions in their national plans and provide annual reports on their water security status; • Regional Bodies - RECs, RLBOs - should adopt the reporting mechanism and provide input to AMCOW’s annual report on progress on water security; • The modalities for a peer review mechanism on country water and sanitation progress shall be developed by the secretariat in consultation with partners; • The AMCOW Secretariat shall be strengthened to monitor and report actions; • The Executive Committee (EXCO) should give directives on themes of future annual Africa Water Weeks and institutionalize the week at the AU level. Africa has now reached the point where there needs to be greater convergence between the high level commitments and delivery through concrete and unambiguous actions, strengthening and scaling up of existing initiatives and refinement of strategies to close gaps. “Whilst continuing to rely on our resources and strategies, we shall continue counting on international solidarity and partnership to address the implementation challenges confronting us in our pursuit of the achievement of the Sharm El-Sheikh Commitments on Water and Sanitation.” Says AMCOW
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AMCOW MINISTERIAL STATEMENT JOHANNESBURG The South African Department of Water Affairs is committed to carrying forward the Sharm El-Sheikh Commitments on Water and Sanitation adopted by the African Union Assembly of Heads of State and Government: “a sprint to the finish line” The African Ministers of Water assembled in Johannesburg, South Africa on 9-13 November 2009, in its capacity as part of the African Union’s Specialised Technical Committee on Agriculture, Rural Development, Water and Environment. This gathering also happened to be on the occasion of the 2nd Africa Water Week, the 2nd Pan African Implementation and Partnership Conference and the 7th Ordinary Session of the African Ministers’ Council on Water. Delegates were determined to carry forward the Sharm El-Sheikh Commitments on Water and Sanitation adopted in July 2009. AMCOW MINISTERIAL STATEMENT JOHANNESBURG AMCOW made the following decisions as follow-up to the implementation of the Sharm ElSheikh Commitments on Water and Sanitation made by the Heads of State in July 2008: Reporting of country actions in respect of water security i. The document “Delivering on Africa’s Water Security Commitments: A Framework for Reporting Actions to the African Union” is adopted as the Roadmap for the Implementation of the Sharm El-Sheikh Commitment ii. Countries should internalise the actions in their national plans and provide annual reports on their water security status; iii. Regional Bodies - RECs, RLBOs - should adopt the reporting mechanism and provide input to AMCOW’s annual report on progress on water security; iv. The modalities for a peer review mechanism on country water and sanitation progress shall be developed by the secretariat in consultation with partners; v. The AMCOW Secretariat shall be strengthened to monitor and report actions; vi. The Executive Committee (EXCO) should give directives on themes of future annual Africa Water Weeks and institutionalize the week at the AU level. In order to carry forward the goals and initiatives of AMCOW attention and actions are brought to the following: i. Convening of meetings of African Water Ministers and Finance Ministers, together with development partners; establishing a short-term African Water Finance Task Force to bring together the finance story, and to monitor impacts of the current financial crisis on investments in African water;
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ii. Accelerating progress on implementing the 2008 eThekwini Declaration and AfricaSan Action Plan, notably the development of national sanitation and hygiene policies; iii. Increasing commitment to the African Water Facility to scale up its support for major infrastructure programmes and projects; iv. Promoting scale-up support to Country Sector Reviews, National MDG Investment Plans and National Finance Strategies; v. Reviewing achievements and to mobilising resources for the Rural Water Supply and Sanitation Initiative (RWSSI) 2nd and 3rd phase implementation; vi. Developing strategies to accelerating progress in drinking water and sanitation in Africa, in particular fragile states, where the coverage gaps are greatest, under the aegis of AMCOW; vii. Encouraging urgent disbursement of implementation funds in small-scale water management in response to the Africa Food Price Crisis; viii. Encourage a stronger collaboration between financial institutions in the framework of Comprehensive African Agricultural Development Programme (CADAP) supporting water for agriculture and energy including the AfDB-Business Plan for agricultural water development, water storage enhancement, the IsDB-Jeddah Declaration and the WB-Irrigation Business Plan;
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ix. Launching and adoption of the pan-African Monitoring and Evaluation (M&E) framework as the monitoring tool in Africa for water and sanitation; x. Planning for the Third African Water Week as a forum for high-level policy dialogue and knowledge dissemination; xi. Strengthening engagement with the G8 over implementation of the Evian Action Plan and Joint Statement of the G8 Africa Water Partnership; xii. Strengthening AMCOW’s presence at sub-regional and national levels, including especially regular convening of sub-regional meetings of AMCOW EXCO and institutionalizing partnerships with regional economic communities; xiii. Adopting special measures to ensure gender mainstreaming, particularly recognising the role and interests of youth, women and children are incorporated in all water and sanitation policies and programmes; xiv. Assessing the threat of climate change to the viability of water resources and capacity to meet the 2015 MDG water and sanitation targets and put in place adaptation measures; xv. Developing and/or strengthening and implementing among riparian countries the water management policies, laws and action plans for the equitable and sustainable use of shared water resources.
chapter 4: climate - rainfall and geology
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chapter 4: climate - rainfall and geology
climate – rainfall and geology Dr. Kevin Winter Lead Researcher Urban Water Management University of Cape Town
CLIMATE AND RAINFALL
The Food and Agriculture Organisation (FAO) of the United Nations regards water scarcity as being the availability of 1 000 m3/capita/annum of freshwater or less (Cessford et al., 2005). Scarcity is a measure of the sensitivity of a given situation to drought. In situations where water per capita is low, any slight variation in availability or in consumption patterns could have disastrous impacts. It is projected that South Africa could face absolute water scarcity by 2025 (Hirji et al., 2002). This chapter presents an overview of the rainfall distribution and climate change of South Africa with the intention of highlighting constraints and challenges for development and environment and to emphasise that progress towards sustainable water resource management is an imperative and not an option. It is worth reiterating for effect: South Africa is a water scarce country and the onset of climate change is a major threat. A brief explanation about the geography of water of South Africa begins with an account of the temporal and spatial variability of rainfall over the country.
RAINFALL: UNEVEN DISTRIBUTION
The average annual rainfall for South Africa is approximately 500 mm, but this is misleading because 65% of the country receives less than 500 mm (O’Keeffe et al., 1992), while 21% receives less than 200mm (DWA, 1986) (See Figure 4.1). The map shows an uneven distribution of rainfall and a steady decline in average annual rainfall from the east to west. Most of the country receives far less than the global average of 860 mm rainfall per annum.
Figure 4.1: Annual average rainfall distribution for South Africa (Source: Schulze et al., 1997).
Average annual rainfall patterns are meaningless other than to illustrate broad differences between regions. In reality, precipitation records show that rainfall is erratic. Studies from 1910 onwards identify cyclical rainfall patterns for summer rainfall regions that vary by as much as 140% above normal rainfall conditions and 70% below (O’Keeffe et al., 1992). These records indicate prolonged dry periods and drought, together with extreme rainfall events, as regular features of South Africa’s geo-hydrological history. However the onset of climate change will cause a significant disruption to cyclical rainfall patterns. the sUSTAINABLE Water Resource HANDBOOK
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Another critical issue is high evaporation rates across the country and especially in the interior and towards the west that will also compromise economic activities and constrain the development and environmental potential of the country. Rainfall only exceeds evaporation at a small number of coastal areas and at certain escarpments. Studies show that in a selection of major South African catchments, the Mean Annual Evaporation (MAE) always exceeded the Mean Annual Precipitation (MAP) (DEAT, 1999) leaving a deficit. Figure 4.2 shows how the average annual evaporation rate (mm) explains the “water loss” along an east to west transect across the country resulting in reduced surface runoff towards the western regions.
Figure 4.2: Annual Average Evaporation (mm) (Source: Shulze et al., 1997)
A further constraint to development, and reason why climate change is a serious issue for South Africa, is that the conversion ratio of MAP to Mean Annual Runoff (MAR) is less than 10% on average. This means that the annual average rainfall that eventually is transferred into streamflow as rivers is relatively small. South Africa and Australia have some of the lowest conversion ratios of MAP to MAR in the world (O’Keeffe et al., 1992). Finally, seasonal rainfall distribution completes the picture of South Africa’s problematic hydrological situation (Figure 4.3). Only a small region to the south east receives all year round rainfall. Most rainfall falls in the mid- to late summer period when evaporation rates are highest, adding further complications and challenges to water resource management. In these circumstances a relatively small temporal and spatial change in temperature and precipitation could have a significant impact on water quantity, quality and distribution, particularly in the interior and western parts of South Africa (IPCC, 2007).
Figure 4.3: Seasonal rainfall distribution (Source: Schulze et al., 1997)
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CLIMATE CHANGE
Since the 1990s the science and interpretation of Global Climate Modelling (GCM) has improved significantly. In particular, regional scale climate modelling has been refined, giving more detailed simulations at higher resolution. This has resulted in information that pertinent to regional water resource management. For example, inferences from climate models weighted for atmospheric CO2 with attention over South African summer and winter rainfall regions, show an increase in the intensity of precipitation events in the north-east parts of the country; an increase in orographic rainfall along the southern coastline; and drier conditions in the southwestern Cape (Hewitson, 2000). GCMs that have doubled the CO2-equivalent concentrations suggest that the following scenarios are likely: a net drying of the western two-thirds of the subcontinent (south of 10 °S); east coast regions are likely to become wetter because orographic rainfall will increase; the Western Cape is predicted to have a shorter rainfall season, while the eastern interior of the province is likely to experience increased late summer rainfall; air temperature will increase across the country; and further changes include a potential increase in floods and droughts (DEAT, 1999).
CONCLUSION
The foregoing discussion has raised numerous issues that impact directly on water resource management. Even slight changes in precipitation and temperature will result in changes in surface runoff in an already water scarce country, putting water availability at further risk. Runoff is expected to decrease by 10% to 30% because of to a decline in rainfall and higher rates of evapo-transpiration (IPCC, 2007). There is also high confidence that the southern Africa region will suffer a decrease in water resources as a result of climate change, with the potential for adverse impacts on sectors such as agriculture, water supply, energy production and health. In addition there is high confidence that those ecological and environmental services that are dependent on water resources will steadily decline, resulting in a loss of biodiversity, among others. In the eastern parts of South Africa where rainfall is triggered by orographic uplift and in the south by frontal uplift, the beneficial influence of increased annual runoff will be tempered by negative effects of rainfall variability and changes in seasonal runoff with consequences for water supply, water quality and flood risk (IPCC, 2007). South Africa has an abundance of natural resources, but not water. While the overall message of this chapter is a negative one, the reality is that current water resources, both quality and quantity, are increasingly in jeopardy. The geography of water, its distribution and variability over space and time, is being stressed by prevailing factors that include climate change, demographics, urbanisation and development. The chapter has omitted to discuss the exact form sustainable development might take, other than to suggest that the approach is an imperative required to address the severity of the challenge and that the approach and practice of sustainable development will be one of the most important challenges facing South Africa society and the sub-continent region as a whole. The obvious implication is that efforts to implement sustainable development is a matter of urgency. REFERENCES Cessford, F. and Burke, J. (2005) Inland Water. Background research paper produced for the South Africa Environment Outlook report on behalf of the Department of Environmental Affairs and Tourism, DEAT, Pretoria. Department of Environmental Affairs and Tourism, (1999) State of the Environment South Africa, DEAT, Pretoria. Available at www.deat.gov.za/soer/nsoer/index.htm Department of Water Affairs (DWA). (1986) Management of Water Resources of the Republic of South Africa, Government Printer, Pretoria. Hewitson, B (2000) Regional Climate Change Scenarios, SANBI. Available at http://www.sanbi.org/countrystudy/Climate%20Scenarios%20Report.pdf Hirji, R., Johnson, P., Maro, P. and Matiza Chiuta, T. (eds). (2002) Defining and Mainstreaming Environmental Sustainability in Water Resources Management in Southern Africa. SADC, IUCN, SARDC, World Bank: Maseru / Harare / Washington, DC. IPCC. (2007). Climate Change 2007: Synthesis Report. Contribution of Working Groups I, II and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, Pachauri, R.K and Reisinger, A. (eds.)]. IPCC, Geneva, Switzerland. O’Keeffe, J., Uys, M. And Bruton, M. (1992) Freshwater Systems in Fuggle, R. and Rabie, A., Environmental Management in South Africa, Chapter 13. Juta. Schulze, R., Maharaj, M., Wartburton, M., Gers, C., Horan, M., Kunz, R. and Clark, D., 1997 South African Atlas of Climatology and Agrohydrology, University of Natal, Pietermaritzburg.
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chapter 5: SURFACE WATER
SURFACE WATER Dr. Kevin Winter Lead Researcher Urban Water Management University of Cape Town
INTRODUCTION
Large scale surface water drainage in South Africa is constrained by landscape topography that is influenced predominantly by the mountainous escarpment that separates a relatively low lying, moist coastal plain with that of a drier, high altitude interior. The chapter describes the constraints and challenges of surfaces drainage, and suggests that too little attention is given to sustainable water resources in a water scarce country.
The geography of surface water
The South African escarpment is like the rim of a dish stretching all the way from the Richtersveld in the north-west, past the Cape Fold mountains in the south and Drakensberg to the east, until it finally reaches the Northern Province. It is a watershed that divides 2 basic drainage systems: the Orange River, while in the other, all rivers flow east and south of the escarpment. The Orange River and Vaal River are the main drainage systems that take water from the interior to the drier arid and semi-arid western coastal region. Rivers draining to the south and east of the escarpment contribute a higher percentage of the mean annual run-off compared to those flowing westwards (Figure 5.1). The most obvious implication is that water yield, especially that which is drawn from the western parts, has to be carefully reconciled within the delicate balance of both surface and groundwater supply and demand. The map illustrates South Africa’s problematic geo-hydrological situation. Just 9% of the total precipitation is converted to surface water, the rest either evaporates or infiltrates into the ground (Shulze, 1997). It is also worth repeating that the Mean Annual Precipitation to Mean Annual Rainfall (MAP:MAR) is among the lowest conversion ratios in the world. The implications are startling. Just a small change in the volume of streamflow could have significant impacts, for example, on the rate of infiltration and groundwater recharge, and how the rate of discharge supports will affect ecological services necessary to support fauna and flora.
Figure 5.1 Primary catchment areas and relative contributions to mean annual run-off (Adapted from O’Keeffe et al., 1992).
Implicit in the foregoing is that surface water drainage involves understanding drainage as a system, rather than a physical network of rivers and streams that drains water from mountainous regions to the oceans. It is an integration of complex and multiple processes. 50
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Rivers: barometers of drainage
Interventions in river systems, whether legal or illegal, abound right across the country and in a variety of ways. For example, rivers are diverted from their natural beds; temporary or permanent water storage dams are built in river beds; water is abstracted from rivers, streams and groundwater without exercise of sufficient control; and patterns of run-off are altered through hardened surfaces, pipelines and canals. In addition, climate change is expected to exacerbate the situation further by causing a decline in surface run-off by as much as 30%. Similarly some regions can expect an increase in the frequency and intensity of rainfall events resulting in an increase in run-off, erosion and loss of valuable topsoil. Rivers, and water bodies in general, respond rapidly to such change and in this sense they are the barometers of land management. For instance a polluted river is indicative of poor environmental management and general neglect. If you want to assess the environmental health of a city or rural area at a glance, look no further than at the condition of the river or rivers in that place. What happens on the land usually ends up in a river! South Africa’s rivers are deteriorating partly as a result of poor surface water management that fails to apply an integrated approach. The National River Health Programme of South Africa found that of the 120 signatures (i.e. fauna and flora indicator species) used to determine the ecosystem health of rivers, 82% of these were threatened, 44% of which were critically endangered (Strydom et al., 2006. The study suggests that ecological systems had collapsed in these critically endangered river systems. Cessford and Burke (2005) raised further concerns in a study dealing with inland water quality in South Africa. Their concerns include: • increasing levels of salinity levels arising from mining, industry and agriculture activities • rising incidents of waterborne diseases such as diarrhoea, dysentery, skin infections, intestinal worms, cholera, arising from bacteria and parasites • decreasing oxygen levels because oxygen is being used increasingly to breakdown organic matter entering surface water bodies • raised levels of eutrophication, often accompanied by algal blooms, caused by an increase in the accumulation of nutrients (nitrogen and phosphorus compounds) entering rivers, lakes and wetlands The “river barometer” is working. The limits on the capacity of rivers to absorb the accumulated impact of pollution have been reached.
Failure of good intentions
The accumulated impact of poor surface drainage is evident in the photographs and captions below. These examples, at a local scale, illustrate how some good intentions to address a particular need could, and do, impact on the flow and quality of surface water.
A private land owner fills in a wetland to raise the level ground for a building project and in so doing raises the risk of flooding surrounding properties. These action also impact on the ecology.
Planners identify land to accommodate migrants moving to the city. This land lies on top of valuable water resources. Polluted surface water resulting from inadequate sewerage and sanitation compromises the long term value of the underground water source.
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Farming to secure a livelihood in a mountainous region. Poor management together with fragile soils and intense rainfall caused erosion and loss of the most fertile soils.
Stormwater removes the risk of flooding, but during low flow periods especially, contaminated drains water directly into the river without any pre-treatment.
Canalising a river removes the risk of flooding and reduces efforts required to manage a river its natural setting, but species habitats and the biodiversity of the system in general have been compromised.
Local authorities provide water to residents in informal settlements, but little is being done to deal with the drainage. Polluted surface run-off from a variety of activities often flows into stormwater systems and then into river, lakes and wetlands nearby.
Sustainable surface water management
3 concerns have been highlighted by the foregoing and each holds implications for shifting toward a more sustainable approach: • Surface drainage is a component of a complex system that incorporates the integration of multiple processes and perspectives including social and political. Integration is critical to improving sustainable surface water management for a variety of reasons. For instance, the approach demands a wider range of detailed information and understanding; an acceptance that surface water is a complex system with multiple elements that make up the system; and that, in practice, processes that embark on an integrated understanding of surface water management, by necessity, build capacities of a broad range of stakeholders that might otherwise have been neglected. • Rivers are indicators of effective sustainability because they reflect the quality and performance of land management. • Poor surface management has an immediate, local impact on rivers. If ongoing, the accumulated impacts have medium to long term impact that compromises the availability and quality of freshwater resources, and will reach a stage when it become impossible to rehabilitate the system because of prohibitive costs. References Cessford, F. and Burke, J. (2005) Inland Water. Background research paper produced for the South Africa Environment Outlook report on behalf of the Department of Environmental Affairs and Tourism, DEAT, Pretoria. O’Keeffe, J., Uys, M. And Bruton, M. (1992) Freshwater Systems in Fuggle, R. and Rabie, A., Environmental Management in South Africa, Chapter 13. Juta. Schulze, R., Maharaj, M., Wartburton, M., Gers, C., Horan, M., Kunz, R. and Clark, D. (1997) South African Atlas of Climatology and Agrohydrology, University of Natal, Pietermaritzburg. Strydom, W., Hill, L., and Eloff., E. (2006) Achievements of the River Health Programme 1994-2009: a national perspective on the ecological health of selected South African rivers, DWAF, Pretoria 52
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Blue Drop Award for Stellenbosch Municipality This prestigious award was awarded to Stellenbosch Municipality at the second Drinking Water Quality Conference in Port Elizabeth which was held from 10 to 11 May 2009. Blue Drop status was awarded to the Paradyskloof and the Franschhoek Water Treatment Works. Idas Valley Water Treatment Works marginally missed the benchmark. Mr Ronald Brown (Head: Sanitation Services and Water Quality Management) and Allen Blanckenberg (Superintendent: Water Treatment and Water Quality) received the award on behalf of the Municipality from the Minister of Water and Environmental Affairs A Water Services Authority with drinking water services systems qualifying for Blue Drop Certification status will formally receive acknowledgement from the Minister of Water and Environmental Affairs and the town will be issued a flag/plague and trophy to display the Blue Drop Certification Status. This will be accompanied by official permission to use the Blue Drop Certification status in the marketing of a town or city for tourism and economic purposes. This is an accolade the Stellenbosch community can be proud of and Stellenbosch Municipality urge the community to report any adverse water quality to the call centre on 021 808 8111. Contact details: Key personnel: Alderman Patrick Swartz, Executive Mayor Tel: +27 21 808 8004 Ian Kenned, Municipal Manager Tel: +27 21 808 8025 Key contact person: Mark Bolton, CFO Physical address: Town Hall, 14 Plein Street, Stellenbosch 7600 Postal address: PO Box 17, Stellenbosch 7599 Tel: +27 21 808 8111 Fax: +27 21 808 8026 Email: Municipality@stellenbosch.org Website: www.stellenbosch.gov.za
Pictured here are (from the left) Ms Buyelwa Sonjica (Minister of Water and Environmental Affairs), Mr Allen Blanckenberg (Superintendent: Water Purification, Stellenbosch Municipality), Ms Mpharu Hloyi (Manager: Scientific Services, City of Cape Town) and Ms Rejoice Mabudafhasi (Deputy Minister: Water and Environmental Affairs).
chapter 6: Ground water use in South Africa
Ground water use in South Africa Dr Martin van Veelen, Director: Environmental Management ILISO Consulting
Introduction
The National Water Act (NWA) of 1998 requires that a National Water Resources Strategy (NWRS) is developed, that will “… provide the framework for the protection, use, development, conservation, management and control of water resources for the country as a whole. ”The first edition of the NWRS was published in 2004, and as the NWA requires an update every five years, the NWRS is currently under review. Although ground water was part of the NWRS, it was not investigated in any detail, and only overall numbers were quoted. No mention is made of a strategy to utilise ground water to maximum benefit as part of South Africa’s water resources in an integrated water resource management plan. Subsequent to the NWRS, the Department of Water Affairs (DWA) developed an Internal Strategic Pespective (ISP) for each of the 19 Water Management Areas. These made provision for the use of ground water as part of the overall water balance for the water management areas, but provided no details on availability, development or assurance of supply. Currently the DWA is in the process of developing water resource reconciliation plans for the most water stressed areas in the country. These plans contain more details on ground water than the previous studies, but are limited to specific areas where ground water is utilised extensively, or is indeed already over-utilised. Some of these studies have shown that the unit reference value (the cost of development per cubic meter of water delivered) for ground water exceeds that for surface water. However, in most cases this is because the true cost for surface water development is not always taken into account. The environmental cost of land and habitat loss due to the construction of a dam, or the impact on the aquatic ecology due to reduced downstream flows, is not calculated. As part of the review of the NWRS the DWA has therefore commissioned a study to develop a National Ground Water Strategy to be included as part of the NWRS.
Availability of Ground Water
Ground water was long seen as separate from surface water, and in the acts that preceded the NWA, ground water was seen as private water, for the exclusive use of the owner of the land. Only some areas were declared ground water control areas, where there were significant quantities of ground water. However, the objective was more focussed on regulating the use of a common resource, than to protect the resource. Ground water is now recognised as part of the water cycle, and indivisible from surface water. At some point in time, and perhaps geographically remote from where it originates, ground water will discharge to surface water in the form of springs or along the banks of streams and rivers to become baseflow. It is therefore not possible to use ground water without influencing surface water flows. There are mainly four types of aquifers in South Africa: • Intergranular aquifers (mainly along the coast and in the Kalahari area) • Fractured aquifers, that represent 80% of the aquifers in South Africa • Karstic (dolomitic) aquifers that provide for high-yielding boreholes • Intergranular/fractured aquifers 54
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The available ground water yield in South Africa is currently estimated at about 10 000 m3/a under normal rainfall conditions, and about 7 500 m3/a under drought conditions (Middleton and Baily, 2009). The current use is about 2 000 m3/a, and it is clear that there is significant scope for an increase in the use of ground water. In comparison, the mean annual runoff in the country’s rivers is about 49 000 m3/a, and the current surface water yield is about 12 000 m3/a, including re-use of return flows (DWA, 2004). Currently the practice is to use ground water mainly as a back-up for surface water during drought conditions. This has advantages, as ground water can be stored over long periods of time without significant loss due to evaporation, as is the case with dams. The disadvantage is that the water has to be accessed by means of many boreholes over a large area, which makes it expensive to develop and difficult to operate.
Conclusion
The development of new surface water resources is becoming more expensive, while the competition for the available water between urban areas, industry and agriculture is increasing. It can be expected that ground water will increasingly become the water resource of choice, and if the resource is not properly protected and the use regulated, some of our aquifers may suffer irreparable damage and be lost. References DWA, 2004. National Water Resources Strategy. Published by the Department of Water Affairs, Pretoria, RSA. September 2004. Middleton BJ and Bailey AK (2009) Water Resources of South Africa, 2005 Study (WR2005). WRC Report Number TT380/08. Water Research Commission, Pretoria RSA 1998. The National Water Act, Act 36 of 1998.
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Ambio Environmental Management Ambio Environmental Management (Pty) Ltd is a full service ecotoxicology and microbiology consulting company. It was established as a specialist environmental services consultancy that provides Ecotoxicological and Microbiological related services primarily, but not limited, to the industries in and around the Vaal Triangle Region in Southern Gauteng. Ambio Environmental Management provides laboratory equipment, testing, field sampling and consulting services to a wide range of clients throughout the world, including many of the largest South African companies, internationally recognized environmental consulting firms and government and public sector agencies. Our goal is to provide scientifically sound data and professional support to assist our clients in meeting their environmental requirements in an efficient and consistent manner. Concerns are addressed from an objective non-biased perspective. The primary focus is to service the needs of the surrounding industries related to water and hydrocarbon testing and as such, the core service relates to routine Ecotoxicological and Microbiological analysis for water and hydrocarbons. Vision To become the preferred Ecotoxicological and Microbiological Environmental Service Provider in Southern Africa Mission Provide objective research and data interpretation pertaining to aquatic and terrestrial ecotoxicology and environmental and industrial microbiology to our clients in a mutually beneficial and practical manner. Support environmentally beneficial and sustainable development initiatives. Values Integrity Honesty and fairness without compromise encompass all our activities. People We respect the individual rights, dignity and uniqueness of all our people. Our individual, collective actions and talents create our competitive advantage. Customers We are committed to providing our customers with value-added services and building mutually beneficial business relationships with our clients. Technology We believe that active involvement in advanced research and development is key to the sustained success of our organisation.
profile Innovation We challenge ourselves to continual improvement. What services do we offer? We operate in three Key Strategic Areas: • Management and Execution of contract projects for local and international agencies in the fields of Ecotoxicology (Aquatic and Terrestrial) and Microbiology • Advisory service for environmental challenges • Technology transfer and capacity building through training Alignment to National, Provincial, District and Local Strategies are very immediate drivers to industries such as the Petrochemical, Water Treatment, Power generation and Mining Industries that are all situated in and around the Vaal Triangle Region and elsewhere in the country. Global conventions and protocols require detailed knowledge of the waste produced by industries. The staff of Ambio Environmental Management (Pty) Ltd have experience working in National and Local government spheres, the Petrochemical industry as well as the mining industry and waterboards. As such the company is well equipped and positioned to be able to provide the best possible services to its clients. Our laboratory is able to provide:• Routine monitoring and analysis for Microbiology and Ecotoxicology requirements • In-service training for students • Independent validation of sample analyses • Instrument endorsement through technology demonstration and development • Standard ecotoxicological modeling services With our specialized focus we can assist you directly with your toxicity and microbiology testing requirements and challenges. Our staff continuously strives to keep abreast of new developments in the field and are active in both standards and methods development. Frequently asked questions: Q Does AMBIO Environmental Management have a standard price list? A AMBIO Environmental provides sample bottles and shipping containers (coolers) at AMBIO’s expense. We also provide the results of reference toxicity tests with test results at no additional charge. Q What is the standard turnaround time for test results? A Preliminary test results are provided via e-mail within 24 hours of test completion. Formal reports for routine testing activities are normally generated within one week of test completion. Q Can AMBIO Environmental assist in the design of testing projects? A Yes. AMBIO personnel can provide guidance on sampling schemes to assist in the interpretation of results. Q Can AMBIO Environmental assist in training staff onsite? A Yes. AMBIO personnel can provide onsite training in the technical aspects of both aquatic and terrestrial toxicology as well as microbiology. Contact Us: Ambio Environmental Management (Pty) Ltd, Andries Potgieter Boulevard, Vanderbijlpark Tel: +27 16 950 9950/51 Fax: +27 86 663 4871 Email: aletia.chapman@vodamail.co.za
chapter 7: The Sustainability Approach: Managing Water as a Flux
The Sustainability Approach: Managing Water as a Flux Prof Anthony Turton Centre for Environmental Management University of Free State
INTRODUCTION
Water is a flux but we manage it as a stock. While this is the foundation of the problem in South Africa, it is also the foundation of any future solution. Prof. Peter Ashton refers to water as being a “fugitive resource” (Ashton, 2000), because it moves in time and space. This manifests as the hydrological cycle in which water is evaporated from the oceans and other open bodies such as lakes, and transpired via the stomata of plants. These two processes are collectively known as evapotranspiration, and in order to understand the nature of the problem we face as a nation, one needs to have a sound grasp of the physics of the hydrological cycle. The evapotranspiration becomes atmospheric water, manifesting as vapour in the form of clouds, which later falls to earth as precipitation (fog, dew, mist, rainfall, hail and snow). The African continent is badly endowed with water because it has the lowest conversion ratio of mean annual precipitation (MAP) to mean annual runoff (MAR) in the world (Gleick, 1993). The MAP:MAR conversion of the various continents is: 45% for Asia and North America; 43% for South America; 35% for Europe, Australia and Oceania; and a paltry 20% for Africa. These are continental averages and they can be misleading, so let us look closer to home for more detailed data. The Orange River basin is the most important for the South Africa because it is the largest and it sustains the economic activity of Gauteng. This river basin is shared between Lesotho, South Africa, Botswana and Namibia making it a transboundary river. The MAP:MAR conversion ratio in the South African portion of the Orange River basin is 3.4% (Ashton et al., 2008), which means that of all the rainfall occurring across the entire geographic extent of that basin, only 3.4% eventually becomes water in the river and thus useable in an economic sense. If one takes the total volume of the average flow of the Orange River as manifest in the South African portion of that basin, and compare it to the total volume of the dams that have been built, we get the MAP:Storage ratio, which shows to what extent we have captured the resource for economic activity and hence to what extent we are vulnerable to the vagaries of nature. In the Orange River basin the total volume of dam storage in the South African portion of the basin is 271.3%, or 2.71 times greater than the actual flow of water in an average year (Ashton et al., 2008). This makes us highly vulnerable in future. In short, South Africa is highly water constrained and the way we manage water in future will determine the rate of our future economic growth and more importantly, the risk that businesses and households will face. Let us unpack this a little more in an attempt to help the reader to start the paradigm shift. The data quoted above all regards water as a stock, because it is cited in specific volumes of water in a specific moment in time. The reason for this is that it is easier to grasp the notion of a stock and then manage accordingly. A stock is the quantity of a given natural resource that is available at a specific moment in time. More importantly, a stock is depleted through consumption. One thus starts off with a stock of a given resource and then uses it over time, resulting ultimately in a depleted resource-base. This can be depicted schematically as shown in Figure 7.1. This sees water being treated like any other natural resource used in an industrial or commercial process, entering the “black box” representing the business entity in one form and emerging at the other end as effluent, 58
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chapter 7: The Sustainability Approach: Managing Water as a Flux
which is degraded and discharged as a waste product. The unintended consequence of this approach is that the cost of water increases over time as the resource-base is depleted, necessitating major capital investment to treat the input water, simply because the quality is so degraded that it becomes unfit for purpose. Water Energy Raw materials
Effluent
Business Process
Product Wealth
Figure 7.1. In any business process, water is traditionally seen as a stock in the same way as energy and other raw materials are regarded.
This paradigm is no longer valid for South Africa if we are to continue to grow our national economy and maintain social stability, so we need to re-think the way we are managing water. Figure 7.2 shows water as a flux in the same configuration as the previous example, except that it is recycled as shown by the feedback loop linking the input and output streams through a recycling process. This causes an increase in the efficiency of the commercial process, and can be thought of as reducing the water footprint of the given product. It also has an increase in production costs, because initially engineering systems need to be incorporated into the overall design of the “black box�, but experience has shown that if this is correctly done then the increased efficiency actually pays for the cost of installation over time. The exact numbers vary for each application so no generic value is possible here, so let us stick to the conceptual level only. The consequence of this is twofold: firstly manifesting as an increased efficiency; and secondly manifesting as an improved quality of the effluent stream, which has benefits to society by removing harmful toxins, endocrine disrupting chemicals and pathogens. Recycling Process
Water Energy Raw materials
Effluent
Business Process
Product Wealth
Figure 7.2. Seeing water as a flux starts off within a factory, business or household with the installation of a recycling system. This initially has a capital cost involved, but if correctly engineered, the improved efficiency outweighs the cost.
How is this manifest in the real world?
At the household level, the water-as-a-stock-paradigm manifests as the need for installing water purification systems as public perception of deteriorating water quality starts to drive purchasing decisions. This is already manifest in South Africa as a burgeoning reverse osmosis and home filtration plant industry; and growing sales of bottled water, often into the poorer sector of the population. At the same level the water-as-a-flux-paradigm manifests as rainwater harvesting, or as grey water harvesting in which water is recycled, typically from the bath, back into the toilet cistern, or into the garden where it can be used for irrigation. This can have health risks if incorrectly engineered, so it opens up opportunities for emerging entrepreneurs, developing products and services to capture this market niche. At the factory level, the water-as-a-stock-paradigm manifests as increased risk over time, partially driven by erratic supply expressed in terms of both quality and quantity. This means that businesses will start to mitigate that risk by increasing their storage capacity, in order to act as a buffer in the event of erratic supplies. It also manifests as the need to install water treatment plants in order to bring the incoming resource up to the desired standard needed for the specific product. As water scarcity manifests nationally, government intervention comes in the form of effluent discharge standards, which means that eventually the effluent stream has to be treated as well. All of this adds the sUSTAINABLE Water Resource HANDBOOK
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chapter 7: The Sustainability Approach: Managing Water as a Flux
cost to the production process and this slowly erodes the profitability of the given corporation, leading eventually to the loss of market share to competitors with lower priced goods. At the same level the water-as-a-flux-paradigm manifests as a strategic rethink at the highest levels of management. This results in a policy shift that starts to understand the flow of water through the given enterprise. In West Australia, for example, many large factories have storage containers that capture runoff from the roof. This is used to augment supply, or to dilute out effluent as needed. It also results in a shift towards internal recycling of water, specifically industrial process water that does not need to be potable standard. At government level the water-as-a-stock-paradigm manifests as a general slow-down of the economy as water service provision becomes increasingly problematic. Associated with this is civil unrest as people protest poor service delivery and increasing prices of water. This is ultimately unsustainable over time. At the same level the water-as-a-flux-paradigm manifests as a strategic rethink that sees the emergence of a policy that I call the dual stream reticulation model, in which two different grades of water are piped into industrial areas. High grade potable water is sold at very high cost, becoming too expensive to use as process water. Lower grade industrial process water is derived from sewage effluent and acid mine drainage management that treats the water to a safe standard for onward sale at a lower tariff for large-scale industrial users (Naidoo, 2009). This was pioneered in the Durban area when the paper and pulp industry combined forces with the petrochemical industry and signed a long-term off-take agreement to buy the treated effluent from the city. This solved the city’s problems of discharging sewage to an offshore pipeline, and it solved the commercial problem of proving lower cost industrial process water, thereby keeping those two industrial partners competitive in the global market.
Managed Aquifer Recharge
Central to the notion of water as a flux, is the deliberate recharge of groundwater aquifers. If one returns to the Orange River basin example noted above, where it has been shown that a staggering 96.6% of all the water falling as precipitation is lost to evapotranspiration, imagine if a small fraction of that could be saved by reducing the evaporation ocurring over large dams? This is achieved by treating water to a high level and then storing it underground for use later on. More importantly that storage has much less loss, specifically if the aquifer being used is confined, than the storage of an identical volume would have in a dam. This is not far-fetched and is already being practiced in California and in West Australia. In the latter case the process involves the treatment of sewage effluent that is currently being discharged out to sea, by means of a series of processes, ultimately using reverse osmosis, and then storing that water in the Leederville Aquifer, which has a permeability rate that will see the water surfacing in 50 years time. This process is shown schematically in Figure 7.3. Sadly South Africa no longer commits serious money to research in this field, so we are no longer regarded as world leaders in the technology. Corporations are starting to view this as a potential future opportunity and they will probably make up for the shortfall in government investment in research and development.
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Figure 7.3. Groundwater recharge is currently being implemented in West Australia. This will take sewage effluent currently being discharged to sea and treat it via a series of processes to make it safe, ultimately being stored in an aquifer for future use. Image courtesy of the Water Corporation of Perth.
Desalination
The National Water Resource Strategy (NWRS) is the official government planning document for the management of water in the country (NWRS, 2004). This document quantifies all of the water and shows it as a stock with numbers reflecting the national situation. The whole country is broken down into 19 Water Management Areas (WMAs) and each is given a future projection in terms of what is known as a Base and a High Scenario, each predicated on anticipated population and economic data. Similar data shows that the four transboundary river basins on which the South African economy depends will have a total deficit of 499 m3 metres in 2025 as shown in Table 7.1 (Ashton et al., 2008).
Table 7.1 Comparison of the current (2000) and projected (2025) water needs with the current (2000) and projected (2025) quantities of water available for the four river basins shared by South Africa (Ashton et al., 2008). (All volumes given in millions of cubic metres per year (106m3yr1): data adapted from DWAF (2003a – k)). Basin
2000 Water Available
Water Needs
2025 (Shortfall) Surplus (+)
Water Available
Water Needs
360
10,816
11,579
(Shortfall) Surplus (+)
OrangeSenqu
9,568
9,208
Limpopo
2,585
2,771
-186
3,778
3,703
75
Incomati
723
972
-249
837
1,017
-180
Maputo
847
468
379
849
480
369
13,723
13,419
304
16,280
16,779
-499
Total
-763
While these figures look depressing, it must be remembered that they represent water as a stock. If the NWRS data is distilled out, then four WMAs manifest as being of critical importance in terms of economic development. These are: the Upper Vaal, which sustains Gauteng and will have a deficit of the sUSTAINABLE Water Resource HANDBOOK
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chapter 7: The Sustainability Approach: Managing Water as a Flux
764 million cubic metres in 2025; the Mvoti to Umzimkulu, which sustains the economic development from Richards Bay to Port Shepstone and will be in deficit of 788 million m3 of water in 2025; the Berg River, which sustains the economic activities of Cape Town and environs and will be in deficit of 508 million m3 of water in 2025; and the Crocodile West and Marico that will be the only significant WMA showing a surplus of 355 million m3, made up primarily of sewage return flows out of Gauteng by 2025 (NWRS, 2004). These are shown in Table 7.2, which also gives an indication of a potential New Water strategy.
Table 7.2 South Africa’s four most critical Water Management Areas WMA
Water Balance 2025
Useable Urban Return Flow in 2000
Urban Demand 2000 New Water Strategy
(NWRS, 2004)
(NWRS, 2004)
(NWRS, 2004)
Upper Vaal
-764
363
635
Sewage return flows
Mvoti to Umzimkulu
-788
57
408
Desalination
Crocodile West & Marico
355
283
547
Sewage return flows
Berg
-508
37
389
Desalination
New Water can be thought of as water that is generated by means of managing the resource as a flux rather than a stock. In this regard a flux can be thought of as a flow over time, rather than as specific volume at a given moment in time. From Table 7.2 it is evident that at least two potential strategies exist. The first relates to the management of sewage return flows and is applicable to the Upper Vaal and the Crocodile West and Marico WMAs. This will probably see the treatment of sewage effluent into industrial process water in keeping with the dual stream reticulation model noted above. In this regard the acid mine drainage problem that is now manifesting in the Witwatersrand Gold-mining Basin is likely to become a combined feedstock for water treatment plants when it is blended with sewage treated effluent. This will mean that no treated effluent will be used for potable water purposes, but this alternative resource will potentially become the foundation for the new beneficiation economy that can be brought into existence at the end of the extractive economy that is now coming to an end as gold mines close. The second relates to desalination, and in this regard the coastal areas are well sited to be considered for such processes. This is all achievable if two things happen. Firstly, the public and business communities need to understand that water is a flux and start to manage it accordingly. Secondly, government needs to understand that there is a way out of the current supply-sided dilemma by means of what is known as the “soft path” that sees water being managed as a flux rather than a stock (Jacobs & Turton, 2009). Our current water crisis, if correctly managed, will become a crucible of new innovation, taking us to new heights of economic prosperity. The choice is ours to make. references Ashton, P.J., 2000. Southern African Water Conflicts: Are They Inevitable or Preventable? In Solomon, H. & Turton, A.R. (Eds.) Water Wars: Enduring Myth or Impending Reality? African Dialogue Monograph Series No. 2. Pp 65-102. Durban: ACCORD Publishers. Ashton, P.J., Hardwick, D. & Breen, C.M., 2008. Changes in water availability and demand within South Africa’s shared river basins as determinants of regional social-ecological resilience. In: Burns, M.J. & Weaver, A.v.B. (Eds.) Advancing Sustainability Science in South Africa. Stellenbosch: Stellenbosch University Press. Pp 279 – 310. DWAF., 2003(a). Limpopo Water Management Area: Overview of Water Resources Availability and Utilisation. Report No. P WMA 01/000/00/0203, September 2003. Pretoria: Department of Water Affairs and Forestry (DWAF). the sUSTAINABLE Water Resource HANDBOOK
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DWAF., 2003(b). Luvuvhu and Letaba Water Management Area: Overview of Water Resources Availability and Utilisation. Report No. P WMA 02/000/00/0203, September 2003. Pretoria: Department of Water Affairs and Forestry (DWAF). DWAF., 2003(c). Crocodile (West) and Marico Water Management Area: Overview of Water Resources Availability and Utilisation. Report No. P WMA 03/000/00/0203, September 2003. Pretoria: Department of Water Affairs and Forestry (DWAF). DWAF., 2003(d). Olifants Water Management Area: Overview of Water Resources Availability and Utilisation. Report No. P WMA 04/000/00/0203, September 2003. Pretoria: Department of Water Affairs and Forestry (DWAF). DWAF., 2003(e). Inkomati Water Management Area: Overview of Water Resources Availability and Utilisation. Report No. P WMA 05/000/00/0203, September 2003., Pretoria: Department of Water Affairs and Forestry (DWAF). DWAF., 2003(f). Usutu - Mhlatuze Water Management Area: Overview of Water Resources Availability and Utilisation. Report No. P WMA 06/000/00/0203, September 2003. Pretoria: Department of Water Affairs and Forestry (DWAF). DWAF., 2003(g). Upper Vaal Water Management Area: Overview of Water Resources Availability and Utilisation. Report No. P WMA 08/000/00/0203, September 2003. Pretoria: Department of Water Affairs and Forestry (DWAF). DWAF., 2003(h). Middle Vaal Water Management Area: Overview of Water Resources Availability and Utilisation. Report No. P WMA 09/000/00/0203, September 2003. Pretoria: Department of Water Affairs and Forestry (DWAF). DWAF., 2003(i). Lower Vaal Water Management Area: Overview of Water Resources Availability and Utilisation. Report No. P WMA 10/000/00/0203, September 2003., Pretoria: Department of Water Affairs and Forestry (DWAF). DWAF., 2003(j). Upper Orange Water Management Area: Overview of Water Resources Availability and Utilisation. Report No. P WMA 13/000/00//0203, September 2003. Pretoria: Department of Water Affairs and Forestry (DWAF). DWAF., 2003(k). Lower Orange Water Management Area: Overview of Water Resources Availability and Utilisation. Report No. P WMA 14/000/00/0203, September 2003. Pretoria: Department of Water Affairs and Forestry (DWAF). Gleick, P.H. (Ed.), 1993. Water in Crisis: A Guide to the World’s Water Resources. New York: Oxford University Press. Jacobs, I. & Turton, A.R., 2009. Water Soft Path Thinking in Developing Countries: South Africa. In Brooks, D.B., Brandes, O.M. & Gurman, S. (Eds.) Making the Most of What we Have: The Soft Path Approach to Water Management. London: Earthscan. Naidoo, B., 2009. Rising Tides: Massive Acid Mine Drainage Project Stimulus for Local Beneficiation, in Creamers Mining Weekly. July 31 – August 6. Pp 8 & 9. NWRS., 2004. National Water Resource Strategy. Pretoria: Department of Water Affairs and Forestry (DWAF). http://www.dwaf.gov.za/Documents/Policies/ NWRS/Default.htm
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profile
The Development Bank of Southern Africa DBSA Vision A prosperous and integrated region, progressively free of poverty and dependency. DBSA Mission To advance development impact in the region by expanding access to development finance and effectively integrating and implementing sustainable development solutions. The Development Bank of Southern Africa is a leading Development Finance Institution (DFI) in Africa South of the Sahara. The DBSA plays five major roles. It acts as a: • Financier that contributes to the delivery of basic services and promotes economic growth through infrastructure and development funding; • Advisor that provides advice to build institutional, financial and knowledge capacity for development; • Partner to leverage private, public and community stakeholders in the development process; • Implementer that originates and facilitates key interventions for building capacity and providing development solutions; and • Integrator that mobilises and links stakeholders, resources and initiatives for sustainable development outcomes. The Bank maximizes its contribution to sustainable development by mobilizing financial, knowledge and human capital to support Government and other development role-players in improving the quality of life of people in the region through funding infrastructure projects; accelerating the sustainable reduction of poverty and dependency; and promoting broad-based economic growth and regional economic integration. Contact details Headway Hill, 1258 Lever Road Midrand South Africa P.O. Box 1234, Halfway House 1685, South Africa Telephone: +27 11 313 3911 Fax: +27 11 313 3086 Web: www.dbsa.org
chapter 8: Protection of Water Resources
Protection of Water Resources Abuse our Water Resources at the Peril of future generations
Bryan Ashe GeaSphere KZN
INTRODUCTION
South Africa has some of the most progressive legislation when it comes to water, this is as a result of Act 108 of 1996 namely the Constitution of the Republic of South Africa enshrining the right to food and water and to an environment that is not harmful to their health and to their to wellbeing. The National Water Act no 36 of 1998 takes this right further and was a major shift away from the previous apartheid era Water Act (54 of 1956) which governed water and continued to reinforce the notion of both private and public control of water inherited from our colonial past. The environment is protected under the National Environment Management Act (Act 107 of 1998) together with National Water Act seeks to provide the legislative framework to protect our water resources. The National Water Act is far reaching in that while it spells out the rights and it is also very clear on the mechanicisms for governance of water and the responsibilities. The principles are sustainability, equity, and efficiency are key cornerstones of the act.,
Sustainability
Building on the notion of protecting the environment it is entails that the water as resource is used in way that promotes economic and social development but at the same ensuring the water resource is protected and that the rights of future generations are protected to adequate water.
Equity
Based on the rights based approach of our constitution the act sees to that provision is made to ensure that all citizens have access to water, but also to ensure that redress takes place of past injustices. That water is equally allocated to all people.
Efficiency
That water is used wisely and not wasted in that it is used to best possible social and economic advantage. The Act is far reaching but like all legislation its implementation has been a different story in the transition post 1994 the Department of Water Affairs and Forestry had to change its focus ensure that equity in water was adequately addressed and in order to that the act transferred the protection of private rights enjoyed under the 1956 act to and in the new 1998 Act the custodianship is placed under the control of the government and to be more exact the Minister of Water Affairs. At the same time post 1994 the challenges of providing potable water to the millions of South Africans who were discriminated under apartheid was the priority and the focus for this was on delivery of water services and access to free basic water which is covered under the constitution and water services act of 1997 and water services strategy of 2003 which gave rise to the free basic water 6kl per household per month. The oversight of the roll out and implementation of was often done by the Department of Water Affairs and Forestry. The water resources component had to ensure that that there was water for the developments and at the same time ensure that adequate water planning was carried out for the future generations. The mindset too had to change as in past the water supply was engineering feats to build mega dams and transfer water across mountains so the industrial and economic hubs of our country had adequate water, but this was at great cost both in terms of monetary, social and environmental costs. In the 1990 the mega dams were being challenged globally and the World Commission on Dams was 66
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chaired by our first democratically elected Minister of Water Affairs Kader Asmal and one people who oversaw the development of the National Water Act. So for the first time we started to see greater participation of the broader society in the development of the Act and subsequent policy that has flowed out of the act. The act sets out to ensure that there is National Water Resource Strategy which was finalized in 2004. The strategy is reviewed every five years (it is now up for review). The strategy seeks to ensure the needs to ensure that there will be water for basic human needs, socio-economic development now and in the future. This process must take place within a framework of stakeholder consultation that is not just a tick box but processes that takes the views and needs and views of stakeholders into consideration. The other part of the act has been to call for the establishment of 19 water management areas or Catchments Management Agencies. These are based on the watersheds of the major catchments in South Africa, but to date only two are partly functional and while others are in the process of being proclaimed. The two only play a role of awareness rising and have not been able to complete their catchments management strategies to point of implementation, they are also subject to financial restraints and operational problems. This is now subject to an institutional review process and it has been recommended that the number be reduced to 9 CMAs, these will not necessarily follow the provincial boundaries as we know them. This process is subject to the completion of a review process. The CMAs have an important role such as the management of the water resources at the catchment level, it made of board that will be representative of the various sectors inter governmental, private sector, NGOs, CBOs and stream flow reduction activities, Agriculture and Conservation agencies. Falling under the CMA are locally based catchment management forum or committee these fora unlike the CMA they are non-statutory and but can play an important role in communication of processes at the local level from pollution, communication of new polices and benefit sharing in the way of new projects for communities in terms IWRM projects etc. More importantly they are the eyes and ears of the Department of Water Affairs. These fora are often overlooked or seen as a threat to local development by local government.
Case study two:
Shortly after 1994 a catchment management forum was set up in on the Isipingo River to monitor fish kills in the estuary and caused by pollution incidents in the canal system of the Prostpecton area of Durban. There were a number of companies that were found to be polluting. DWAF issued compliance orders for industries to comply with and how to remedy the problems and in some cases they fined the some of the companies. The fledgling Catchment Management Forum made a recommendation that the companies that were involved in the pollution also apologize and explain to the down stream residents what they had done to prevent further incidents of pollution. As a result of the media coverage and the “naming and shaming� pollution in this area dropped off for quite a few years and the industries themselves became the watchdogs as they watched their neighbors. The fines were not the deterrent in this case but the negative publicity More importantly the role of the Department of Water Affairs changed yet again in 2009 following the national elections the Ministry of Water Affairs and the Ministry of Environment were merged while the Departments themselves retain autonomy. Other changes that were made were that Water Service provision has been devolved down to local government level with municipalities and Sanitation has been handed over to the department of human settlements while forestry has been combined with Agriculture and Fisheries. Once the institutional reform process is complete then the CMA will start to take more responsibility for every day management of water resources and some of the functions that are played by the Regional offices of DWA The Department Of Waters Affairs will now not be responsible for the delivery of services will move into the role of regulator and support services and will be better equipped to take role of the regulator of both water services and water resources together the planning for future water provision together with policy development. the sUSTAINABLE Water Resource HANDBOOK
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chapter 8: Protection of Water Resources
The role DWA of regulator will be ensure that the Water Resources and Water Services are regulated and to this end Water Services Regulation Strategy has been competed this strategy is awaiting approval and the Department is in the final stages of the Water Resources Regulation Strategy once this is completed the Water Regulation Framework will provide the necessary tools for the protection of water resources in South Africa. Under the National Water Act the classification of water play and important part in ensuring the balance between natural ecosystems along rivers and the socio-economic drivers of development in our catchments. The process is takes into account the present state of the river, if the water is polluted and the condition of the riparian vegetation. This process should be done in consultative manner. A number of rivers were monitored under the river health program and reports generated. In terms of the official classification of rivers in South Africa a process was started but is still incomplete. The other area that is important when looking the water quality is the resources quality objectives. These objectives are used to monitor quality of water in a river and benchmark the water quality of a river. In this process the quantity (including the levels and timing of flows in the river), the water quality (physical, chemical and biological), what the condition of the inseam and riparian habitat and the condition of the aquatic animal and plant life are taken into account. This process is monitored on a regular basis and deadlines are set to see by which in the cases of water quality can be improved upon by better management of the resource. While this well and good in practice when it comes to impacts of activities such as the extractive industries the historical events that cause pollution such Acid Mine Drainage often leave much to be desired in the remediation of these impacts and it has only been the exposure through the media by NGOs and academics that this issue is now receiving some attention. The other issue that comes up is the role of local industry in a given area, if the resource objectives were enforced industry claims they would leave town. What needs to be looked at is mechanism for the support of cleaner production support for these industries. Every river should have a water reserve determination, especially those rivers that are the work horse rivers, i.e. Vaal, Umgeni and. The reserve is the amount of water needed to provide for basic 68
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human needs and to protect the water ecosystems (sustaining healthy ecosystems). This is the only right to water given in the national water act. In other words it would be a serious problem if economic activities such as agriculture, industry and mining were given priority over basic human needs, with out alternative water supply being investigated or provided. The other key area is the ecological reserve as without this reserve a river would not be able maintain its eco-system services in ensuring that the correct quality and quantity of water to sustain the basic human needs and that of economic development. The reserve determination is set in terms of the National Water Act by the Minister of Water Affairs based on the advice of the Department of Water Affairs.
Case study two:
Historical water use in a work horse river such as the Umgeni River in KwaZulu Natal, would mean that if the full ecological reserve was enforced the human needs would place the major part of the population in water restrictions. Water is supplemented from the Mooi River in water transfer scheme and a further water storage scheme is planned for the Mooi River. One the most important parts of water management is the ensuring that the ecological services remain intact and functioning. This is not just at the level of local rivers but also the grasslands and wetlands that make up a catchments or watershed. When activities are planned that may impact on these resources we will see the impact down stream. One of Africa’s gems the iSimanagaliso Wetland Park and Lake St. Lucia was under threat of mining a few years ago. The lake was in part under the custodianship of provincial nature conservation and the Department of Water and Forestry. The system is part of a catchment that has three major rivers flowing into each over the years has seen different forms of sustainable development take place. In 1952 a young game ranger took part in the first aerial count of Rhino in Zululand and one of the things that he noticed was degradation of the catchment. Today it is no different coal mining, sugar farming and industrial tree plantations have all taken their toll and together with extended drought have seen the lake at an all time low. In 2007 on a visit to the area we drove through industrial tree plantations on the western shores of the lake and we noted that the streams were low and the absence of water in some areas. In August 2009 we attended a meeting of NGOs to review progress on the creation of the isimangaliso Wetland Park and what we saw was reduction of the industrial tree plantations from the Western Shores in accordance with an agreed hydro-ecological line and the complete removal of the plantations from the eastern shores. The difference was immediately evident in that streams had started to flow again, and even though drought conditions still prevailed water was infact being recharged from the swamps and wetlands. It is this example of that shows how important the ecosystems are as Lake St. Lucia is one of the most important nursery areas on the east coast of Africa for marine eco-systems. Only one part of the catchments has been partially rehabilitated yet we have seen a vast improvement in the two years. Other catchements are not so lucky the Msunduzi Catchment has severe wetland and soil erosion problems that have seen huge increases in the silt load of the river. This has in turn lead to silting up of the Henley Dam and has increased the silt load in the Umgeni system. In other areas mining and in particular open cast coal mining has the potential impact on three important wetland systems namely The Chrissiesmeer Lake District, Lakenvlei and Groenvlei systems in Mpumalanga. In the fringes of these important wetlands system are the sources of several major rivers namely the Vaal, Komati (via the Boesmanspruit), the uMpuluzi River and the Usutu River Existing mining operations in Witbank area has had impacts of Acid Mine Drainage into water of the Olliphants systems added to the an already polluted River. This so we may have power generated from coal at the expense of the sustainability of our precious water resources The irony of the mater is that some of South Africa major power generating plants are situated here in this region too and by placing a strong reliance on one source of energy we are looking not only at having repeats of the energy crisis, but also impacting on the source of life Water and undermining the suitability of the resource for future generations so the immediate development needs of cheap energy for industry can be met. the sUSTAINABLE Water Resource HANDBOOK
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profile
Intaka Tech – meeting the water needs of remote communities The provision of sufficient, pure, potable water in Africa is becoming ever more challenging nowadays, and no more so than in the case of far-flung, scattered, remote or peri-urban communities that are often overlooked in terms of this essential provision. Intaka Tech Water Purification Plants (WPPs) are ideal for use in such conditions. It comes as no surprise therefore that many Intaka Tech WPPs are to be found hard at work in out of the way areas, provinces and countries in Africa. A division of the Intaka Group, Intaka Tech manufactures and markets state-of-the-art water and gas equipment. The primary objective of this solutions-driven company is to improve and enhance the lifestyle and well-being of its target market. Service delivery pressure Government is currently under pressure in terms of service delivery, especially in the water sector and with the provision of pure water to remote communities. Intaka Tech is able to assist here and offer immediate solutions to drinking water problems. The WPPs and their components can easily be transported to their destination, no matter how remote it may be, and installed without complications. This degree of mobility allows the WPPs to be operational within six days once the plants have been delivered. Pressing water requirements can therefore be met in a very short space of time. A case in point A case in point is South Africa’s Northern Province, in which a number of Intaka Tech WPPs are in operation, with further installations expected. The Northern Cape is a particularly large province with many small, sparse, peri-urban communities, villages and towns, the distances between which are often vast. Ten Intaka Tech Water Purification Plants (WPPs) are currently in operation at different hospitals throughout the Northern Cape, helping to boost facilities, replace ageing infrastructure, and enhance the quality of water at hospitals in this province. Together, their maximum capacity is 8 580 000 litres of potable water per day.There are seven model WPP050 units, each of which is able to produce up to 1 100 000 litres per day; one WPP025, able to produce up to 550 000 litres per day; and two WT 0.75, each of which are able to produce up to 165 000 litres per day. “We are pleased to be able to assist in providing all South Africans with access to pure water and to help enhance their wellbeing,” says Rodrigo Savoi, Intaka Tech CEO. “Our objective is
profile to work in partnership with Government to contribute to its goal to provide effective, appropriate services to comprehensively address South Africa’s healthcare needs. ” The Intaka Tech WPPs are also suitable for rural municipalities where the current water sources are not sufficient to warrant larger schemes or where the relevant technology is not in place. Two WPPs (model WPP050) are in operation at Sol Plaatje Municipality in the peri-urban communities of Ritchie as well as Raaswater near Upington in the Northern Cape. Intaka Tech WPP features The WPP models not only remove turbidity and colour, but also eliminate bacteria, spores, viral and parasite pathogenic agents, thus preventing typical waterborne diseases. All models are manufactured from grade 304 stainless steel making them corrosion resistant and extremely durable to the elements and the water treatment process. The WT 0.75s are purification models for water that is reasonably clean, where the primary focus is to eliminate odour and taste. The purification process comprises sand filtration, followed by Granular activated carbon (GAC) filtration to remove the odour and taste, and finally chlorination.
No matter how remote your location, the mobile Intaka Tech Water Purification Plant (WPP) will provide you with pure, pristine water - easily and cost-effectively. And you can rest assured that the water our WPP produces is in accordance with SABS 241:2006, as well as the criteria stipulated by the World Health Organisation (WHO). The Intaka Tech WPP can provide up to 50 000 litres per hour. It is manufactured from grade 304 stainless steel, making it corrosion resistant and extremely durable to the elements. It perfects water purification processes for the healthcare, food and brewery industry, as well as for mining communities and the defence force.
PURE WATER ON TAP 24/7 Being a solutions-driven company, Intaka Tech’s products offer practical, distinctive features. These include low cost, mobility, easy installation and operation, not to mention uncomplicated maintenance. And all Intaka Tech’s equipment is backed by the company’s comprehensive after sales support network, as well as its service and maintenance agreement, which includes the supply of operational chemicals.
An additional, optional benefit of the Intaka Tech WPPs, is that they offer water softening. This is of particular advantage to the Northern Cape as the water there tends to be ‘hard’, a typical condition where water has elevated levels of calcium and manganese.
Intaka Tech (021) 702 1559
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URBAN USE OF WATER Dr. Kevin Winter Lead Researcher Urban Water Management University of Cape Town
INTRODUCTION
Urban water use includes both domestic (residential) and industrial use within urban areas, but excludes large industries that abstract water directly, such as Eskom and Sasol (DWAF, 2009). In this chapter the discussion is confined to urban domestic water consumption which is usually the largest proportion of total water demand in large cities and where there is the greatest potential for water conservation. Domestic water consumption is increasing in South African cities because of urbanisation, population growth, new users who previously had limited access, and lifestyle choices. At a national scale, current projections estimate that the population will grow to 53 million by 2025 that will lead to an increase in domestic water consumption by between 3% and 8% (DWAF, 2009). Current national domestic demand is approximately 27%, although this is much higher because it should include a share of “urban� which includes servicing functions such as sewage works, municipal functions and also water losses caused by leakage (Table 9.1). Water user / sector
Proportion of allocation
Agriculture
62%
Domestic
27%
Urban
23%
Rural
4%
Industrial
3.50%
Afforestation
3.00%
Mining
2.50%
Power generation
2.00%
About 16 million people (37% of the population) live in the main economic centres with 26% of household dwellings in these cities being largely without on site water services. Of the 12 million dwellings, 63% are classified as formal. The remainder consists of informal and backyard dwellings in urban areas, and traditional housing in rural areas.
DOMESTIC WATER USE
Worldwide urban water consumption values per capita vary considerably. Studies suggest that typical values are divided into low, typical and high demand corresponding to 50-, 300- and 650 litres/capita/ day (l/c/d) (White et al, 1996 cited in CoCT, 2005). In the City of Cape Town studies showed that low-, typical- and high translated to 50-, 150- and 300 l/c/d (CoCT, 2005) and could indicate that a minimal value, as recommended by the World Health Organisation (WHO) being 50 l/c/d, is being met, at least for Cape Town. In formal, serviced homes, studies worldwide confirm that the toilet, washing machine and bathshower represent the largest indoor end-uses of water, and that the combination of these contributes approximately 75% of total consumption, but this varies considerably with income (CoCT, 2005) (tableure 9.1). Garden water demand contributes most to residential water demand, although the the sUSTAINABLE Water Resource HANDBOOK
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share of water used for irrigation varies considerably from one study to another and is influenced by myriad of factors including size of plot, climate and ability to pay. In general studies on household consumption patterns have had mixed results, and many studies are based on perceptions of usage rather than actual values captured by metering devices attached to appliances and conveniences such as toilets and baths, etc. (CoCT, 2005).
Figure 9.1: Water consumption in households in two different income groups
CHANGING CONSUMPTION PATTERNS: FACTORS INFLUENCING DEMAND
A comprehensive study conducted in South Africa found that the most significant factors affecting domestic water demand were the size of stand (house and surrounding area), household income, water price, available water pressure, type of development (suburban vs township) and climate (Van Zyl et al., 2007). The study also found that domestic water demand was significantly higher for inland stands than coastal stands, and that water demand related strongly to both the value of the stand or income and stand size. Higher income users show a seasonal variation in demand due to the use of water to garden irrigation during the dry season (Van Zyl et al., 2007). The study highlights a number of mechanisms and strategies aimed at reducing water demand. However, these strategies will find little success, and therefore be unsustainable, unless solutions are found within a wider debate about what is considered “fair” water consumption and equitable access to water for the urban poor. A further issue is the capacity of local authorities to communicate and inform water consumers. Building relationships of trust and co-operation is paramount. The issues and questions that follow focus on issues of sustainability: just and equity opportunities to access sufficient water without compromising the right of future generations or damaging the integrity of freshwater systems in meeting the supply.
The price of water
Price elasticity is used commonly in water demand management studies as a way of measuring consumer response to a change in the price of water. Water is generally accepted as price inelastic meaning that consumers can be expected to reduce their consumption level with increasing cost. Consumers are particularly responsive to price increases in the use of water for outdoor activities around the home – irrigating gardens, topping up swimming pools, etc. (Van Zyl et al., 2007). A block tariff system has been introduced in most metro municipalities to ensure that the level and associated cost of water usage is taken by the consumer themselves. The tariff ensures that those who consume more than their share of existing water resources should be made liable. However, this raises 74
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new questions that remain unresolved. Do consumers have the right to consume over and above their water resource allocation? Part of the answer lies in understanding the impacts of extracting water from catchments and transferring this to urban areas, which is the current, conventional practice. Is the real cost of water being adequately met to include the environmental cost of storing water in large dams? Simply put, is the price of water too cheap? These are questions will intensify as urbanisation increases along with increasing demand. A second issue relates to the allocation of Free Basic Water (FBW). All consumers, irrespective of their consumption levels, are entitled to 6 000 litres / household / month of water. In 2001 FBW was introduced nationally as a critical contribution to alleviating poverty and also in recognising that water is a basic human right. However, it is questionable whether 6 000 litres is adequate to service the needs of the poor. RDP type houses often accommodate more than 4 people so the basic allocation becomes insufficient. For example, if 6 people share a house, this will mean that each member has a daily water allocation of 33 litres per capita per day. The price debate is a complex one. Worldwide studies show that water is price sensitive (CoCT, 2006). An increase in price reduces demand but it also generates much needed revenue for capital programmes to renew and operate water-based infrastructure.
Pre-paid meters
Meters have been introduced by metro municipalities in order to charge for consumption over the basic 6 000 litre allocation. However, the installation in poor households has raised considerable debate and protest. In one case, Phiri residents (Soweto) took the City of Johannesburg to court. After 6 years of preparation and hearings the court finally ruled that that FBW fell within the “bounds of reasonableness and therefore is not in conflict with either section 27 of the Constitution or with the national legislation regulating water services. The installation of pre-paid meters in Phiri is found to be lawful” (Constitutional Court ruling, 2009). The merits of the Phiri case cannot be debated here, except that the underlying issue remains one of inadequate water allocation and not the actual meter device. The use of pre-paid meters to manage water (e.g. in the case of leak detection) is an appropriate water demand management tool and is arguably essential for sustainable water resource management. The challenge is rather to ensure that pre-paid meters become useful tools in themselves, and do not obscure critical questions about equitable access and reconciliation of water resources.
Informative billing: consumer education
Sustainable solutions to water demand management in urban areas also lie in appropriate interventions that will motivate consumers to comply. Many municipalities avoid opportunities to inform consumers often because they do not have the capacity or financial resources. Yet clear, concise and creative information, at the very least, can make a substantial contribution to managing water demand. The case study of the Greater Hermanus Water Conservation Programme (GHWCP) is one such case study that demonstrated how communication and information could make a substantial difference. The Municipality and the Department of Water Affairs and Forestry established a collaborative programme aimed at promoting equity, efficiency, and sustainability in the supply and use of water in this coastal town (Turton, 1999). A few years after the programme was introduced in 1996 the results showed that: • Per capita peak-demand for water was reduced by 32%. • Revenue from water sales increased by 20% despite the decreased demand • Water became available and affordable to the poor • Improved governance, job creation jobs and a ‘sense of community’ was enhanced through the programme The programme comprised a 12-point plan that included the installation of water-efficient devices, e.g. dual flush toilets, and an informative monthly billing system that graphically showed users how much water they have consumed over a 13-month period The GHWC programmes made an important contribution to water demand management tools and knowledge. The success of the GWHC programme is well known, but the wider impact of the the sUSTAINABLE Water Resource HANDBOOK
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study appears to be limited. Examples of good practice in water management exist in many parts of the country, but too little heed is being paid to identifying these projects and programmes and as a result are not followed up by a commitment to implement similar work elsewhere.
RETURN FLOWS
Since toilets use the greater proportion of household water, attention needs to focus on this household facility such that it could limit the water use or even be operated in a waterless environment. Alternative toilet technologies are being developed and are finding a local market, but in many cases they require further research and compliance. In addition, attention also needs to be given to changing user thinking and behaviour. Waterless toilets and urine diversion systems could pose a health and environmental risk, yet this should not deter research and further assessment. Prototype systems are being piloted around the country. For example, biodigesters are able to treat effluent, sludge and organic waste on site. At the same time the system is capable of capturing and using methane as a by-product. Figure 9.2 shows an example of a household that is generating approximately 4 hours of gas daily that is used for cooking and heating. Moreover, the system does not return any water back into a municipal sewerage system.
Figure 9.2: A bio-digester pilot project
SUSTAINABLE WATER USE
Water demand management strategies, tools and devices are well known but often underperform because social and economic contexts are misunderstood or taken for granted. Inequalities and poverty cannot be brushed aside. Thus simplifying the issues, and avoiding questions about access and excess serves only to polarise the debate. Sustainable urban water management requires a fresh approach to establishing relationships between officials, stakeholders and water consumers, and built primarily on knowledge and capacity to collectively address South Africa’s water crisis. Ongoing research and experimentation should attract funding to advance science, technologies and social understanding. Technological advances worldwide suggest that cost effective sanitation systems and decentralised treatment works may offer new innovations and opportunities to advance sustainable ideals. However, the rush to acquire new technologies should be carefully researched. REFERENCES City of Cape Town Muncipality (2005) Water Consumption Study – Report 1, CoCT City of Cape Town Municipality (2008) Smart Living Handbook, 2nd Edition, CoCT Department of Water Affairs and Forestry. (2009) Water for Growth and Development Framework, Version 7, RSA Government, Pretoria [Available at www.dwaf. gov.za/masibambane/watergrowth.asp] Van Zyl, J., Van Zyl, L., Geustyn, A., lemobade., I. and Buckle, J. (2007) Water Consumption levels in selected South African Cities, WRC Report No 1536/1/06 ISBN 978-1-77005-480-6 Turton, A. (1999) Water Demand Management (WDM): a case study from South Africa. MEWREW Occassional Paper 4. Presented to the Presented to the Water Issues Study Group, School of Oriental and African Studies (SOAS) 76
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profile
The Chemical and Allied Industries’ Association The Chemical and Allied Industries’ Association (CAIA) was established in 1994 to promote a wide range of interests pertaining to the chemical industry. These include fostering South Africa’s science base; seeking ways to promote growth in the sector; promoting the industry’s commitment to a high standard of health, safety and environmental performance; and consulting with government and other role players on a wide variety of issues. Membership is open to chemical manufacturers and traders as well as to organisations which provide a service to the chemical industry, such as hauliers and consultants. CAIA is the South African custodian of the international Responsible Care initiative, which has been adopted by 53 countries worldwide.
This is a key component of the work of the Association. CAIA obtains guidance on the implementation of the initiative through its principal, the International Council of Chemical Associations (ICCA). 167 members are now signatories to Responsible Care in South Africa. Responsible Care is an initiative of the global chemical industry in which companies, through their national associations, commit to work together to continuously improve the health, safety and environmental performance of their products and processes, and so contribute to the sustainable development of local communities and of society as a whole. It encourages companies and associations to inform the public about what they make and do, about their performance including reporting performance data, and about their achievements and challenges. CAIA promotes a proactive relationship with government. Advocacy efforts are primarily channelled through Business Unity South Africa (BUSA) which represents business in the National Economic Development and Labour Council (NEDLAC). Contact details Dr M D Booth, Director Information Resources, Tel: 011 482 1671; E-mail: caiainfo@iafrica.com
profile
Zimbabwe National Water Authority Historical Background ZINWA was established by an Act of Parliament on the 1st of January 2000 through the amalgamation of the Regional Water Authority and the Department of Water Development in the then ministry of Rural Resources and Water Development. The Authority’s mandate is to manage eater for the State and to ensure sustainable development and equitable distribution of the country’s water resources to all Zimbabweans at an affordable price. Vision To be a world class water resource planning, developmental and management authority. Mission ZINWA commits itself to ensuring optimum planning, development, utilization and management of Zimbabwe’s water resource in an efficient, equitable, sustainable and socially desirable manner, with the participation of stakeholders. Our maxim “WATER IN LIFE, EVERY DROP COUNTS’ fully captures the fact that there is no substitute for water due to its finite and fragile nature. It should be conserved and protected from pollution so it can enhance our health as citizens and give life to our economy through its efficient use in the entire production sector. The Aims and Functions of Zinwa are: • Provide water to the nation in a cost effective manner • Ensure equitable accessibility and efficient use of water resources • Minimize the impacts of droughts and floods • Assist catchment’s councils in their functions • Provide technical assistance, training and consultancy on a cost recovery basis • Operate and maintain water works in order to provide water in bulk to local authorities, and reticulated water to consumers on behalf of local authorities who lack the capacity to provide this service • Undertake research, develop databases and produce maps • Promote co-operative management of internationally shared river basins. • Advise on water policy and national standards on:
profile 1. Water resources planning, management and development 2. The implementation of water quality and pollution control 3. Environment protection 4. Dam safety 5. Hydrology and Hydrogeology 6. Water Pricing and policy Core values Innovation; Professionalism; Integrity; Commitment; Accountability; Responsibility. ZINWA Divisions Zinwa has various divisions with diverse responsibilities which assist in the effective execution of its functions. These include the following: Planning Division The Planning Division is one of the four units performing statutory functions. Its mandate is to ensure compliance with the Water Act, national water policy and strategy requirements in relation to the planning, development and management of the nation’s water resource. Data and Research The mandate of this unit is to capture, archive and disseminate data on surface and ground water resources’ availability and ensure equitable allocation of the resource. Design and Construction The unit has the mandate of designing and supervising the construction of all water conservation works and also offering engineering advice and consultancy services. Groundwater Division This division performs statutory functions through the investigation of groundwater resources in the country in terms of their location, potential volumes and yields. It also monitors the quality of the ground water and collects data. Quality Assurance The division performs a statutory function through ensuring the quality of water, recommending water treatment chemicals and ensuring that the Authority adheres to environmental standards. Water Supplies The division supplies clear water to small towns, growth points, and rural services centers the Zimbabwe National Army, National Parks and Wildlife and schools. Head office: 12th Floor, Old Mutual centre, Cnr 3rd Street / Jason Moyo Ave, P.O Box CY617, Causeway, Harare, Tel: +263-4-797604-7; Fax: +263-4-700732, Email: pr@zinwa.co.zw
chapter 10: URBAN DRAINAGE
URBAN DRAINAGE Dr. Kevin Winter Lead Researcher Urban Water Management University of Cape Town
INTRODUCTION
In urban areas where there is a formal drainage system, unwanted water is typically channelled into stormwater systems then discharged at the “end of pipe” into water bodies such as rivers, lakes and wetlands. This conventional approach to managing urban drainage was designed to reduce flood risks. It is now widely recognised as an unsustainable practice primarily because water can no longer be treated as unwanted or wastewater because of impacts on the receiving environment. Runoff from hardened, impervious surfaces, together with stormwater reticulation systems, has severely impacted on the natural water cycle of urban areas and has contributed to the deterioration of urban water bodies (CoCT, 2009). In additions hardened surface decrease the potential for runoff to infiltrate and recharge the groundwater.
DRAINAGE IN FORMAL SETTLEMENTS
“Typical” pollutant concentrations found in stormwater worldwide were established from a review of water samples extracted from various reports (Duncan, cited in Bratieres et al., 2008). Table 10.1 shows “average” stormwater concentrations taken from the point of discharge at 3 sites in Cape Town and lists these alongside those found elsewhere. Except for Total Suspended Solids (TSS) the table shows greater pollution loadings in Cape Town compared to “typical” concentrations worldwide. Nutrient concentrations found in the Cape Town samples are indicative of polluted water that often induces excessive growth of phytoplankton in the receiving water bodies with consequent impacts on aquatic ecosystems. Table 10.1: Average concentrations from 3 stormwater pipes in Cape Town alongside “typical” pollutant concentrations worldwide
Chemical properties (mg/L)
Average levels for Cape Town
Typical pollutant concentrations worldwide
Total suspended solids TSS
28.8
150
Total Nitrogen TN
4.7
2.10
Ammonia NH3
1.3
0.27
Total Phosphorous P
0.6
0.35
Storm or flood hydrographs illustrate the change in the rate and volume of flow in a river following a rainfall event. The line graph in Figure 10.1 shows how the discharge of water in a river, measured in cumecs (cubic metres per second) at a given point, varies over time in response to rainfall (mm). The line graph shows three different types of flow depending on prevailing conditions: day-to-day discharges vary as a result of groundwater seepage into the river channel (baseflow); peak discharge occurs during a storm event when the river reaches its highest level; and throughflow occurs once most overland flow has been discharged into the river after a rainfall event. The lag time between a storm event and peak is of particular interest since a combination of hardened surfaces and conventional urban drainage systems reduce this lag that then results in an increase in the peak flow, potential for flooding and a reduction in infiltration. In addition there is an increase in erosion of river beds and banks; an increase in habitat disturbance; higher sediment and pollution transfer rates; and 80
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a decrease in the baseflow (loss of groundwater seepage through a reduction in recharge). Urban hydrological data are seldom captured, even by larger municipalities in South Africa, leaving a gap in the knowledge management of urban catchments, and drainage in particular.
Figure 10.1: A generalised stormwater hydrograph
DRAINAGE IN INFORMAL SETTLEMENTS
For South African residents living in non-sewered informal settlements, especially where municipal services are rudimentary or are dysfunctional, the removal of unwanted water is a daily concern. Running water, whether from tapstands, leaking toilets, or from that which has been disposed on the ground, forms numerous informal rills and channels between houses and open spaces and periodically ponds. Some of this flow reaches stormwater catchpits, but typically infiltrates the soil. The problem is particularly acute in high density settlements where there is limited surface area to absorb the runoff. Foul, polluted water then flows through these settlements and seriously compromises the health of residents, especially children who tend to play in these polluted waters. Samples captured during a recent research project at informal settlements in the Western Cape showed excessive levels of Escherichia coli (E. coli) (over 1800 cfu/100ml), a bacterium commonly found in the lower intestine of humans and mammals and if ingested, could poison the human body resulting in illnesses such as dysentery and diahoerra (Armitage, et al., 2008). In low lying settlements where the drainage is usually poor, these surface waters become vectors for distributing disease. During the rainy season heavily polluted water has nowhere to escape. Residents in parts of the Western Cape have no alternative but to live in homes that remain flooded for weeks with water containing high densities of bacteria and pathogens. Furthermore salts, oils, grease and other chemicals accumulate in the immediate environment of the settlement and contribute to unhealthy conditions.
SUSTAINABLE URBAN DRAINAGE
Sustainable urban drainage is about designing urban environments to closely match the water cycle in an attempt to mimic the quality and quantity of surface runoff before development occurred and to optimise the use of rainwater that falls in the urban area. It implies that stormwater must be managed as a water resource without compromising the ecological health of receiving water bodies or posing a public safety risk. There are many initiatives in cities worldwide, and increasingly in South Africa, where sustainable urban drainage principles and practices are being applied. The photographs and captions below provide a brief snapshot of some of these initiatives the sUSTAINABLE Water Resource HANDBOOK
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Top international speakers Large exhibition of transport and mobility products and services Case study based workshops Networking functions Design and technology demonstrations •N ational infrastructure stakeholders • P orts and harbour authorities • K ey government decision-makers • S hipping and marine commercial companies •A irport authorities and related organisations •A irfreight and logistics companies • R ail network operators and stakeholders •C ity planners and designers •U rban mobility planners •A utomotive industry stakeholders • R esearch institutes • V ehicle technology companies •M echanical engineers and engine designers •U niversities • F uel, gas and bio-fuel tech companies • T raffic management • P ublic transport operating organisations
April 29th and 30th 2010
The Sustainable Transport and Mobility Conference and Exhibition is the event for South Africa’s leading transport sector stakeholders, policy-makers, designers and specifiers.
For further information http://www.transportandmobility.co.za
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Ponds and biofilters
A constructed reed wetland that receives stormwater from nearby roads. Sediment and some nutrients settle in the pond before the water is discharged into the adjacent river. Ponds provide on-site detention to reduce peak flows; store water for re-use; provide an aesthetically pleasing environment; and provide infiltration and a reduction in stormwater runoff.
A scientific experiment in progress to assess which plant species are best able to absorb nutrients and heavy metals found in stormwater. The experiment also examines the accumulation of toxins in the soil. The objective is to use this information to improve the design of biofiltration trenches that retain, cleanse and encourage stormwater infiltration.
Porous paving and swales
Porous pavements allow water to infiltrate the paving substrate and eventually enter underlying subsoils. Stormwater runoff is retained; peak flows are reduced along with the overall volume of stormwater runoff; and the transfer of sediments and pollutants from a site is reduced. (Photo courtesy: N P Armitage)
Swales are depressions that are used for the conveyance of stormwater runoff. They reduce total runoff through infiltration; capture sediment and pollutants; and reduce the speed of runoff.
Green roofs and rain gardens
A green roof acts as a biofilter and reduces runoff that would otherwise Drainage from road surfaces is directed into a small garden where have reached stormwater systems via roof gutters and downpipes. plants and soils act as a filter improving water quality before entering (Photo courtesy: N P Armitage) stormwater catchpits.
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Initiatives in informal settlement – irrigation and trench filters
Greywater, generated from bathroom of an informally built house, is being used to irrigate fruit trees in the yard.
A resident is seen building a makeshift greywater soakaway. An upturned beer crate provides the opening to the trench. This filter provides a temporary means of managing wastewater and also reducing general runoff from the site. It must be seen as experimental and may not work in conditions elsewhere.
POLICY DRIVES CHANGE TOWARDS SUSTAINABLE DRAINAGE
The City of Cape Town has developed policy to support the objectives of sustainable urban drainage with the intention of reducing flood impacts on livelihoods and regional economies to safeguard human health; improve recreational water quality; and protect natural aquatic systems (CoCT, 2009). The City will use this policy to address 3 specific objectives: • Improve quality of stormwater runoff • Control quantity and rate of stormwater runoff • Encourage natural groundwater recharge (CoCT, 2009) The City is already applying this policy to all new developments. It intends to monitor water quality at the point of discharge and compare against recognised water quality benchmarks. The release of this policy initiative provides a first step in addressing existing urban drainage and a means of intervening in the design stages of new planned developments.
CONCLUSION
The application of sustainable urban drainage begins with a shift away from the conventional approach of treating excess water as unwanted or wastewater. In a water scarce country, every drop must count. In large municipalities in South Africa, policies and plans are being introduced that are intended to reduce the rate of runoff, as well as improve water quality of the receiving environment and to recharge groundwater. New opportunities should be highlighted, to manage urban drainage so as to contribute to improvements in human health, livelihoods, water resources and health of aquatic ecosystems. Efforts to improve drainage in informal settlements remain a huge challenge for a variety of social, political and economic reasons. Until such time as suitable solutions are found in these settlements, all runoff (including stormwater, sanitation and greywater), should be treated as sewage (Carden et al., 2007). REFERENCES Armitage, N., Winter, K., Spiegel, A., and Kruger, E. (2009) Community-focused greywater management in two informal settlements in South Africa, Water Sci Technol. 59(12):2341-50. Bratieres, K., Fletcher, T., Deletic, A., Zinger, Y. (2008) Nutrient and sediment removal by stormwater biofilters: A large-scale design optimisation study, Water Research 42 pp 3930-3940. Carden, K., Armitage, N., Winter, K., Sichone, O., and Rivett, U. (2007) Understanding the Use and Disposal of Greywater in the Non-sewered Areas in South Africa. WRC Report 1524/1/07. Knox City Council (2002) Water Sensitive Urban Design Guidelines for the City of Fort Knox, Knox City Council, Australia. 84
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Center for Aquatic Research – University of Johannesburg The Centre for Aquatic Research (CAR) consists of a blend of internationally acclaimed (NRF-rated) and upcoming researchers. Each participant contributes a specific field of expertise that, when combined creates the most comprehensive research group of its kind in Africa. Training and services within the Centre are represented at three different levels; i.e. research-based Masters and PhD programmes, a tutored Masters programme and accredited short courses in riverine and wetland ecology, management and remediation in conjunction with the UNESCO/Flemish Government/WRC funded FETWater programme. Specialist aquatic and estuarine consulting services are provided through Econ@UJ.
Internationally acclaimed research expertise Researchers at CAR have developed a branch of aquatic research into the field of freshwater and estuarine ecotoxicology. Ecotoxicology is the science that studies the influence of human activities (from global, e.g. global warming to a more local perspective, e.g. multiple stressors in the Vaal Barrage) on the environment. Research and scientific services is focused on all aspects of ecotoxicology ranging from toxicant identification and environmental distribution (i.e. quantify and qualify levels of metal and organic pollutants using bioaccumulation studies and artificial devices) to biological / environmental effects (i.e. at different levels of biological organization from subcellular to ecosystem responses) to management implications (e.g. through the ecological risk assessment paradigm). Contact details: Centre for Aquatic Research, Department of Zoology, PO Box 524, Auckland Park, 2006, Tel. +27 11 559-2441, Fax: +27 11 559-2286. Research related: Prof. Victor Wepener – victorw@uj.ac.za Short courses: Mrs. Tahla Ross – fetwater@uj.ac.za Econ@UJ consulting: Mr. Wynand Malherbe – econ@uj.ac.za
chapter 11: URBAN WASTEWATER TREATMENT
URBAN WASTEWATER TREATMENT David J. Nozaic Pr Eng, SFWISA Founder and Manager Dave Nozaic cc Consulting Water Process Specialists
INTRODUCTION
In situ sewage treatment is necessary in areas which are not served by regional (usually municipal) sewage reticulation and sewage plants. Depending on the demographic and social factors this may take the form of dry systems such as pit latrines or EcoSan systems, or for areas provided with waterborne sewage this can be achieved by the use of septic tanks and soakpits, and in fact this method of treatment and disposal can be applied to larger complexes where the soil percolation is good and there is adequate land area available. For larger settlements or complexes the use of oxidation ponds may be an attractive low technology solution. It does, however, require suitable terrain and sufficient land area for the ponds and associated irrigation areas. These can be proportionately quite large relative to the overall size of the development and are therefore more suited to rural areas. If any of the above methods is not suitable then some form of sewage treatment plant is required. These plants may be either purpose designed for the application, or standard commercially available units (package plants).
Dry Systems
Dry systems usually consist of pit latrines Ventilated Imrovement Privy which are basically holes in the ground into which the faeces and urine are directly discharged. These require cleaning out usually after a period of about 5 years and this is often a difficult operation with problems as to the ultimate sludge disposal. More recently, there have been a number of designs for self-composting toilets. Here the waste is discharged into a ventilated chamber where the solids become dessicated and stabilized. The clearing of these is less unpleasant. Some of the designs provide for separate treatment of the urine and faecal matter which aids the drying process. Another fairly new development is the Ecological Sanitation (EcoSan) approach which uses separate urine and faecal treatment and attempts to return the nutrients to the soil in a self-sustaining process. This is the subject of a separate chapter in this manual.
Septic Tanks and Soakaways
In its most basic form a septic tank can be a single-compartment watertight tank with an inlet pipe discharging below the surface and an outlet pipe at the top water level baffled to prevent discharge of scum. Normally, however, even for single housing units, a 2 or even 3 compartment tank is provided to receive the sewage. In a 2 or 3 compartment tank, the compartments are separated by vertical walls with openings above mid-water level so as to retain primary sludge or scum in the first compartment as far as possible. The process taking place in a septic tank is an anaerobic one and treatment is only partial. The septic tank therefore does not produce an effluent complying with the General Authorisation limits for discharge to land or watercourse. Limited irrigation use of effluent is permissible under certain circumstances, but generally septic tanks are used before percolation or soakaway systems for small applications, or as a preliminary or first stage before secondary aerobic treatment. Percolation systems for septic tank effluent should generally be located such that pollution of 86
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surface or ground water is unlikely to occur. There are no simple tests by means of which the suitability of a soil to absorb septic tank effluent can be determined accurately. Indications can be obtained by visual inspection of the soil, i.e. whether it has a sandy or clayey nature, or a percolation test may be carried out.
Conservancy Tanks
Small package plants are not always successful in treating non-domestic sewage, and it is sometimes a requirement of a municipality that sewage from shops and offices be collected in conservancy tanks and periodically removed from site to a central sewage works. Conservancy tanks may also be used when the soil characteristics are unsuitable for percolation
Package Plants
Package plants generally use the same technologies as larger plants but there are processes which are better suited to small scale or conversely to large scale applications Favoured technologies in South Africa include fixed media systems (RBCs, biological filters and submerged biological contactors), activated sludge systems and combinations of the treatment technologies with many of these preceded by septic tanks. A well designed plant will produce an effluent that complies with statutory requirements.
Waste stabilisation ponds
Waste stabilisation ponds are large shallow basins enclosed by earthen embankments in which raw sewage is treated by natural processes involving both algae and bacteria. Because of the use of natural processes, the rate of oxidation is slow and as a result, long hydraulic retention times are employed, retentions of 30 to 50 days being normal. Ponds have considerable advantages, particularly regarding costs and maintenance requirements and the removal of faecal bacteria, over other methods of treating the sewage from communities of more than about 100 people. Ponds are the most important method of sewage treatment in hot climates where sufficient land is normally available and where the temperature is most favourable for their operation. There are three major types of pond relying on natural processes: • Facultative • Maturation • Anaerobic ponds In addition to this, aerated lagoons are ponds fitted with mechanical aeration devices, that enablessmaller units to be constructed.
Biological filtration (Trickling Filters)
Biological Filtration (Trickling Filter) provides a unit process for wastewater treatment that does not require sophisticated technology and has relatively low power and operating costs. A biological filter (Biofilter) normally treats wastewater that has been settled in a Primary Sedimentation Tank (PST) or a septic tank, and comprises a bed of media, which may be a granular material such as crushed stone, or synthetic packing media which may be either stackable or contained within a structure. Settled sewage is sprayed or trickled over the top surface of the bed, through which it percolates. The filter is aerated either by natural draft or by forced ventilation to provide oxygen to the purification process. Slime containing a large number of organisms forms on the surface of the media. As the sewage flows over this slime a series of complex bio-chemical reactions take place by which organic material is removed from the sewage. The organisms require oxygen and this is obtained from the air circulating in the filter bed. Hence, maximum ventilation should be provided. The slime increases in thickness until eventually portions break away and are carried out of the bed in the effluent. This material is known as “humus” which has to be separated from the effluent in a sedimentation tank. The effluent that has passed through the filter is directed to collector drains by slopes in the floor and conveyed to a secondary sedimentation tank (humus tank) where the solids are settled out. The clarified effluent is either discharged or partly recycled through the biofilter to improve performance. the sUSTAINABLE Water Resource HANDBOOK
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Activated Sludge
The activated sludge process effects oxidation of organic compounds similar to a biological filter but whereas sewage trickles over a packed bed in a biofilter, the activated sludge process necessitates that oxygen is introduced by mechanical means into the liquid. In the biological filter, the purifying micro¬organisms are attached to the media as a relatively thin film, but in the activated sludge process these micro-organisms are suspended in the liquid as an “active” sludge. The process comprises a reactor basin in which micro-organisms are suspended in the sewage, oxygen is introduced by mechanical means and bio-chemical reactions take place by which organic pollutants are removed from the sewage. The suspended active sludge is separated from the effluent in a clarifier and is returned to the reactor. The mass of active sludge continually grows and sludge has to be wasted from the system from time to time to maintain the correct balance. It should be clearly understood that the active sludge is a living microbial culture that develops in the process. This active sludge is not composed of the sludge which is introduced with the sewage, but grows as a result of the organic “food” present in the influent. The composition and characteristics of this active sludge are determined by various factors such as the composition of the sewage, the retention time in the reactor, aeration rates and patterns and the average age of the sludge.
Membrane Bioreactors (MBR)
Membrane bioreactors are a recent innovation in wastewater treatment and make use of the activated sludge process in a modified form. In this type of plant the clarifier is replaced by semiporous membranes arranged in sheets or tubes in the aeration reactor. The treated effluent passes through the membrane while the activated sludge is left behind. This avoids the need for a clarifier and sludge return pumps but is not always significantly cheaper because the membranes can be expensive. However, it is a beneficial process for upgrading plants that are overloaded because it can operate at very high MLSS concentrations and short liquid retention times. It is also useful where compactness is an important consideration. The MBR process utilises microporous membranes for solid/liquid separation in lieu of secondary clarifiers. This very compact arrangement produces a MF/UF quality effluent suitable for reuse applications or as a high quality feed water source for Reverse Osmosis treatment. Indicative output quality of MF/UF systems include SS <1mg/L, turbidity <0.2 NTU and up to 4 log removal of virus (depending on the membrane nominal pore size). In addition, it provides a barrier to certain chlorine resistant pathogens such as Cryptosporidium and Giardia. The MBR process is an emerging advanced wastewater treatment technology that has been successfully applied at an ever increasing number of locations around the world. In addition to their steady increase in number, MBR installations are also increasing in terms of scale. A number of plants with a treatment capacity of around 5 to 10 ML/d have been in operation for several years now while the next generation (presently undergoing commissioning or under contract) have design capacities up to 45 ML/d. The membranes are in the MF/UF range with a typical pore size of 0.4 μm and are of the low pressure type. Most designs use flat sheet membranes but there are hollow fibre and tubular designs available. Sludge is wasted from the reactor as in a conventional process and the MBR system has the advantage that pre-thickening of the sludge for dewatering is often not necessary
Artificial Wetlands
The potential of artificial or constructed wetlands as a reliable and fundamental process for the secondary treatment of wastewater and for nutrient removal has received considerable attention during the past 20 years. The discharge of wastewaters into constructed wetlands may be considered a viable alternative treatment option, particularly suited to small and medium sized communities in sparsely populated and developing areas. It is generally accepted by researchers that wetland systems have considerable potential and may offer a number of advantages compared to conventional wastewater treatment options: • Low operating cost • Low energy requirements • Low maintenance requirements • Can be established close to the site of wastewater production 88
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• • • •
Can be established by relatively untrained personnel Robust process able to withstand a wide range of operating conditions Environmentally acceptable offering considerable wildlife conservation opportunity Can readily be integrated into existing forms of effluent treatment
A constructed wetland consists of a shallow, often lined excavation (depending on acceptance of seepage to the ground system) containing a bed of porous soil, gravel or ash, in which emergent aquatic vegetation is planted (commonly Phragmites Australis). The settled sewage or septic tank effluent is evenly distributed over the width of the bed and flows through it at a suitable rate to permit biological oxidation, nutrient removal, and pathogen removal to proceed to an advanced stage. The effluent from a well designed system will comply with statutory requirements.
New Innovations
Most new innovations in sewage, largely package plant systems, appear to be hybrids that combine the advantages of the fixed film processes (low sludge production) with the high standards of effluent obtainable from the activated sludge process. There are a number of examples of suspended growth systems using sponge balls or other media to support organism growth in suspended aeration systems similar to activated sludge. These plants tend to be compact and do not require large clarifiers. Reference Design Manual for Small Sewage Works; WRC; 2009; Nozaic D J and Freese S D. (In the process of being printed)
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Ugu District Municipality The Ugu District Municipality (DC21) is 5866 km² in extent and it is one of the ten districts of KwaZulu-Natal. The IsiZulu word “Ugu” means “coast”. The area is bordered on the north by the eThekwini Municipality and on the western side by the uMgungundlovu and Sisonke Municipalities and the Eastern Cape Province. Vision A non-racial society of healthy and empowered people living in a safe, transformed and sustainable environment, underpinned by a thriving and growing economy in which all participate and benefit fairly and equitably Mission Enhancing our performance and work ethic to reach world-class standards, by placing emphasis on customer satisfaction and total quality management of all resources at our disposal Values T = Thoughtfulness H = Holism I = Integrity N = Non-partisanship K = Knowledgeability Currently the Ugu District Administration has four departments namely: • Corporate Services • Treasury • Infrastructure and Economic Development • Water Services DID YOU KNOW? That Ugu District Municipality is the water and sanitation services authority and provider for the Ugu District. DID YOU KNOW? That Ugu District Municipality embarked on a community liaison programme titled “Operation Ong’amanzi” – A campaign aimed at informing communities regarding the progress on all issues related to water and sanitation.
profile DID YOU KNOW? That Ugu District Municipality continuously informs communities about the changes in the pre-paid standpipes to free-for-all standpipes and water conservation. This process was solely aimed at raising awareness against vandalism and illegal connections in the water supply system, through Operation Ong’amanzi. DID YOU KNOW? That Ugu District Municipality’s Free Basic Water Policy grants 200 litres of clean drinkable water for free to all consumers and 400 litres per day for Indigent consumers. DID YOU KNOW? That Ugu District Municipality has a credit control policy designed for those consumers who have fallen in arrears in the payment of water accounts. Consumers wishing to enquire about this facility may contact Ugu on 039 688 5820/1 DID YOU KNOW? That Ugu District Municipality spends millions of rands every year to maintain a reliable and affordable service to its customers? DID YOU KNOW? That Ugu District Municipality is fully committed to service delivery as the community can expect communication campaigns, educational programmes, consultative meetings and general awareness campaigns. DID YOU KNOW? You can forward your water and sanitation queries to Ugu’s Customer Care Centre. See below for contact numbers. The National Water week commemorated from 2 - 8 March 2009, in Ugu District Municipality saw the commissioning of two, multi-million rand water schemes, benefiting the communities of KwaLembe under Vulamehlo Municipality and Nyavini under Umzumbe Municipality. Mayor Cele handed over the KwaLembe Water Supply Scheme valued at R30 057 189. The water scheme is designed to supply water to 16 360 people within the KwaLembe Tribal Authority benefiting over 600 people with short-term employment during construction. “The project was done in four phases with phase one and two dealing with abstraction from Umkomaas River and treatment works and the extension of power supply to the pump stations and treatment works.” Phase four involved reticulation and the construction of 102 standpipes. Mr Bheko Ngubo, who is in charge of DWEA’s water sector support in the Ugu Region urged the public to conserve water as it is life. Speaking on behalf of the department, Mr Ngubo also talked about how DWEA has taken a pledge to assist Ugu bring water services to the people. “We assist the municipality bring services to the people in terms of water.” This project alone created employment for 130 people, 67 of which were women. Mayor Cele also mentioned that the Umzumbe area has other significant projects nearing completion. “Among other projects in this area, fairly soon, the municipality will hand over a water project covering Ward 12, 13, 14 and 16. We are currently monitoring the upgrades that we have recently completed in the area,” said Mayor Cele. He added that Ugu is confident of a great improvement in the supply of water to this area. CUSTOMER CARE CALL CENTRE TOLL FREE NUMBER – 0800092837 Account queries: 039 688 5854 or 039 688 5836 www.ugu.gov.za
chapter 12: SMALL AND PACKAGE PLANTS
SMALL AND PACKAGE PLANTS David J. Nozaic Pr Eng, SFWISA Founder and Manager Dave Nozaic cc Consulting Water Process Specialists
INTRODUCTION
In situ sewage treatment is necessary in areas that are not served by regional (usually municipal) sewage reticulation and sewage plants. For individual dwellings or small complexes this is usually achieved by the use of septic tanks and soakpits, and in fact this method of treatment and disposal can be applied to larger complexes where the soil percolation is good and where there is adequate land area available. If this method is not suitable then some form of sewage treatment plant is required. These apply and operate on the same principles as larger regional plants but are suitably sized to the particular application. These plants may be either purpose designed for the application (small plants or mini works), or standard commercially available units (package plants). The traditional approach when planning a development would be to appoint a competent consultant or designer who would assess the probable volume of sewage and load requiring treatment, and would choose a suitable process configuration, and size and construct a plant to achieve the required performance. The alternative approach is to find a plant supplier who can offer a standard design out of a range of products which most closely matches the clientâ&#x20AC;&#x2122;s requirements. If a contractor with a wide range of alternative technologies is chosen then this approach has a fair chance of success as the supplier is then in a position to offer the most suitable technology. However, many manufacturers have only one type of plant in various sizes and this may not always be the most suitable process for the application. If we limit small and package plants to a maximum flow of 500 kl/d (up to 3000 persons) there are not many package plant options available in the upper ranges of flow suggested, and for many designs a suitable limit may be more like 50 kl/d with a contributing population of 250 to 300 persons. As one moves upwards from 50 kl/d towards 500 kl/d and beyond there is an increasing advantage and favouring tendencies towards purpose designed mini works as the cost of individual design becomes proportionately less.
Technologies Employed In Small And Package Plants
Package sewage treatment plant systems could be divided into those that make use of anaerobic process to treat sewage, and those that make use of aerobic treatment systems, although many systems rely on both mechanisms. Systems employing the more complex technology with aerobic treatment include Rotating Biological Contactors (RBCs), activated sludge systems (which include Sequencing Batch Reactors (SBR) and Membrane Bioreactors (MBR)), as well as Submerged Aerated Filter Media plants. Aerobic treatment is essential if there are to be options for reuse as the effluent is then of much higher standard and will normally comply with the GLVs (General Limit Values) set for effluents by the Department of Water Affairs.
Activated Sludge Plants
Activated sludge plants are some of the most simple in concept, consisting essentially of an aerated tank where naturally developing activated sludge carries out the purification, and a settling tank where the sludge is settled out from the effluent and returned to the aeration tank usually by means of a pump. 92
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The aeration tank can be just about any shape consistent with good oxygen transfer. Aeration of the tank can be by coarse, medium, or fine bubble diffusion; by air suction induced by a venturi or a cavitational submerged pump; or by rotating paddles or brushes. Some settling tanks are baffled compartments in the aeration tank, or a separated section of the aeration tank structure, or can be separate units. Return sludge from the clarifier back to the aeration tank can be by air lift pump, or centrifugal pump. Excess sludge can be dried on beds or tankered away An activated sludge plant needs a greater degree of operational attention for setting up than most of the other alternatives.
Points to consider are:
• T he plants are generally quite compact and the shape can be adapted to site conditions to some extent. • The capital cost of activated sludge plants is generally lower than most alternatives, but the operating costs are usually higher due to the higher power costs associated with aeration. • It can be expected that the specific power consumption will be somewhat higher for small plants, particularly diffused air plants where the transfer efficiency is roughly proportional to tank depth. However, the impact of higher power costs is not as important on small plants compared to other factors. • Activated sludge plants are generally odour-free. If odours are present the plant is either severely overloaded or there has been a power failure or fault with the aeration equipment. • Certain types of blowers can be noisy in operation and need to be housed to minimise their impact. The splashing sound of surface aerators can disturb sensitive residents close-by at night. • The concentration of activated sludge in the system is important. This can be maintained by measuring the mixed liquor suspended solids (MLSS) in the aeration tank routinely and wasting from the system to maintain optimum levels. • In view of the expertise needed to operate an activated sludge plant well, it is normally recommended that a competent consulting chemist visit the plant to monitor it on a routine basis. • The process can be modified to reduce or remove nutrients in the effluent. • The activated sludge can build up to excessive levels and needs to be periodically wasted from the system by tankering away (can be expensive) or drying on drying beds (can cause odour). • The effluent from a well run and well designed plant is usually excellent quality but will require disinfection (chlorination).
Sequencing Batch Reactors (SBRs)
These are a modification of the activated sludge process and many of the comments above are applicable. The difference lies in the elimination of the settling tank and batchwise aeration and settling in successive cycles in the aeration tank. Points to consider are : • The capital cost of an SBR plant should be less than a normal activated sludge plant through elimination of the settling tank • The operating costs should be similar • The plant is slightly more vulnerable to mechanical or electrical breakdowns because its operation depends on float switch and timer sequenced cycles • SBRs work well if operating at relatively low loads. They are however more vulnerable to overload conditions
Membrane Bioreactors (MBR)
Membrane bioreactors are a recent innovation in wastewater treatment and make use of the activated sludge process in a modified form. In this type of plant the clarifier is replaced by semiporous membranes arranged in sheets or tubes in the aeration reactor. The treated effluent passes through the membrane while the activated sludge is left behind. This avoids the need for a clarifier and sludge return pumps but is not always significantly cheaper as the membranes can be expensive. However, it is a beneficial process for upgrading plants that are overloaded as it can operate at very the sUSTAINABLE Water Resource HANDBOOK
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high MLSS concentrations and short liquid retention times. It is also useful where compactness is an important consideration. The MBR process utilises microporous membranes for solid/liquid separation in lieu of secondary clarifiers. This very compact arrangement produces a Microfiltration quality effluent suitable for reuse applications or as a high quality feed water source for Reverse Osmosis treatment. Indicative output quality of MF/UF systems include SS <1mg/L, turbidity <0.2 NTU and up to 4 log removal of viruses(depending on the membrane nominal pore size). In addition, it provides a barrier to certain chlorine resistant pathogens such as Cryptosporidium and Giardia.
Submerged media plants
These plants are a hybrid between activated sludge in that the treatment tank contents are aerated and a trickling filter plant in that contact media is used. The treatment tank is often preceded by a primary settling compartment or septic tank although this is not universal. The media is submerged in the tank and oxygen supply to the biological slime on the media is by means of air diffusion usually with some form of mixing/circulation to give multiple passes. The plants are claimed to have the advantage of good purification efficiency with low sludge growth requiring minimal wastage (significantly less than the activated sludge process). Points to note are: • The plant is compact although there does not appear to be much difference between the size of these plants, duty for duty, compared to other types • Power consumption should be similar to that for an activated sludge plant • The big advantage, compared to activated sludge is the lower sludge production, with good effluent quality still being obtained • There is a potential problem of clogging of media with certain designs due to inadequate clearance and this leads to poor transfer efficiency and reduced performance
Design Aspects
There are a number of problems specific to small works and package plants:
Scaling-down
The problem lies in the impracticality of reducing some items below a certain size to match the needs of a small plant. For example, a large plant may have a 150mm diameter sludge pipeline. On a small plant the same calculation may yield a 10mm pipe diameter. This would be way below the minimum diameter pipe in which it is practicable to convey sludge without frequent blockages occurring, so that design compromises have to be made.
Pipes and pipework
The problem of sizing of sludge pipes was given as an example above. It used to be conventional wisdom that one never used less than a 150 mm pipe for sludge (particularly raw sludge) in sewage applications. The acceptable diameter has reduced over the years with improvements in design and 100mm and even 75mm sludge piping applications are in existence. However, the basic problem remains. A 40 kl/d plant requires a pipe of 50 – 60mm diameter which could give problems over long distances. The compromise is to flow or pump intermittently but this then impacts on the sizing of the settling tank. For small sludge volumes the percentage operating time may be very small.
Pumps
The same type of limitations that apply to pipes also apply to pumps. A raw sewage pump on a large works is usually designed to pass a 75mm sphere which obviously means that the pump casing , suction and delivery pipework have to be at least that size. This is often impractical on small plants where such a size of pump would have a very short duty cycle.
Oxygen Transfer in Activated Sludge
Aeration of activated sludge plants can be either by mechanical aeration or by diffused air. 94
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Mechanical aeration is usually by vertical shaft turbine aerators which are sized on paddle tip speed so that smaller units tend to rotate faster. This can reduce the mixing effect. Diffused air aeration has a transfer efficiency which is roughly proportional to the depth of immersion of the diffuser. Thus a small 2m deep tank will require about twice as much air as a larger 4m deep tank for the same load. Fine bubble diffusion is over twice as efficient as coarse bubble diffusion which is often used in package plants. The end result can be a need for four times as much air per unit load
Chlorination
Gas chlorination is not feasible on the smaller plants and one usually uses either calcium or sodium hypochlorite. Drip feed devices are sometimes necessary on small plants but their performance is nearly always erratic and they should be avoided if possible. Sodium hypochlorite dosage by diaphragm pump is a preferred method of dosage for consistency but the chemical deteriorates quickly on standing (within weeks) and stocks need to be fresh and rotated on a strict in-first/out-first basis.
Characteristics of Influent
To our knowledge without exception all package plants on the South African market use biological treatment processes for purification. The feed or influent therefore needs to be biodegradable for the process to work effectively. For this reason package plants are not a good option if effluents other than domestic sewage require treatment. This applies to factories or any other developments where difficult effluents may be produced. For example, shopping centres can pose problems where there may be several restaurants giving effluents with high fat contents, and hairdressing establishments which use harsh chemicals. Hospitals and clinics may discharge excessive quantities of disinfectants.
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Capricorn Municipality VISION Capricorn District, the home of excellence and opportunities for a better life MISSION To provide quality services, in a cost effective and efficient manner, through competent people, partnerships, information and knowledge management creating sustainability of economic development in the interest of all stakeholders. Overview Capricorn is a district with diverse local economic development opportunities in different sectors such as Tourism, Agriculture, Mining and Manufacturing. It falls under Limpopo Province, located on the Northern side of South Africa. It is a “Capricorn region”, which is predominantly rural in nature. The Capricorn District is the third largest district economy in Limpopo Province, the Capital, Polokwane, lies in the heart of the Capricorn region. The District has an internal airport and is lined to Gauteng by one to the best stretches of the in N1 in South Africa. Capricorn District Municipality is made up of five local municipalities namely, Aganang, Blouberg, Lepelle-Nkumpi, Molemole and Polokwane. Economic profile Capricorn District is among the highest contributors to provincial gross geographic product and has a fairly reasonable infrastructure, which can build a solid foundation for economic development and growth. It is indeed a prime investment destination. CORE MANDATE The Capricorn District Municipality mandate is derived from the Constitution of the Republic of South Africa, 1996 (Act No. 108 of 1996), which mandates Local Government as to: • Provide democratic and accountable local government • Ensure provision of services to communities • Promote safe and healthy environment • Encourage the involvement of communities • Powers and functions POWERS AND FUNCTIONS CDM is a category C municipality that has both the executive and legislative authority in an area that includes more than one municipality. The powers of the district as mandated by Section 84 of the Municipal Systems Act are as follows: • Water supply • Electricity supply • Bulk sewage purification and disposal
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Solid waste disposal in the area of the district as a whole Municipal roads, which forms an integral part of a road transport system Regulation of passenger transport services and municipal airports Municipal health Fire-fighting services Establishment, conduct and control of fresh produce Markets and abattoirs Cemeteries and crematoria Local tourism Receipt, allocation and distribution of grants Imposition and collection of rates and taxes Concurrent functions IGR imperative MEC adjustments
Municipal Systems Act (32 of 2000) requires WSAs to conduct Section Processes and determine the best delivery models. Capricorn District Municipality (CDM) therefore in terms of the legislative prescripts of the Municipal Systems Act (32 of 2000) undertook a final Section 78 process in 2007. The outcome of that processes recommended that CDM adopts a hybrid of service delivery options as the model for water service provision as follows: • CDM appoints the local municipalities as WSP’s for retail water services (except for Polokwane); • CDM has appoints Lepele Northern Water (LNW) as bulk water service provider; and • That CDM embarks on an exercise to establish a water service provision agency, possible titled “Capricorn Water Agency” Contact details: Tel: 015 294 1000 Fax: 015 291 4297 Email: info@cdm.gov.za www.cdm.gov.za
chapter 13: DECENTRALISED SANITATION AND RE-USE
DECENTRALISED SANITATION AND RE-USE David J. Nozaic Pr Eng, SFWISA Founder and Manager Dave Nozaic cc Consulting Water Process Specialists
INTRODUCTION
There are 1.2 billion people in the world today without access to safe drinking water, while 3 billion people do not have access to proper sanitation. In addition, 50% of solid wastes remain uncollected. At the World Summit on Sustainable Development (WSSD) in 2002, it was agreed to reduce by half the proportion of people without basic sanitation by 2015. The development of appropriate technical options and implementation methods plays a pivotal role in meeting these objectives. Ecological sanitation (EcoSan) can assist in meeting these objectives.
EcoSan approach
EcoSan can be viewed as a three-step process: containment, sanitation and recycling of human excreta. The objective is to protect human health and the environment while reducing the use of water in sanitation systems and recycling nutrients to help reduce the need for artificial fertilisers in agriculture. EcoSan represents a conceptual shift in the relationship between people and the environment, and is built on the necessary link between people and soil. The EcoSan approach to sanitation promotes a cycle, or “closed system”, where human excreta are treated as a resource. Excreta are processed on site and then, if necessary, further processed off site until they are completely free of disease organisms. The nutrients contained in the excreta, are then recycled by using them as fertiliser in agriculture. Ecological sanitation is being used by vast numbers of people across the world including Sweden, Germany and countries such as Zimbabwe, Ethiopia, Mexico, El Salvador and China where hundreds of thousands are serviced by ecological sanitation systems at very little cost to the environment. Ecosan is aimed at closing the nutrient and water cycles. Nutrients from human excreta should be returned to the soil to fertilise crops. Urine is diverted from faeces in eco-toilets, and reused as fertilizer. Faeces potentially contain pathogenic micro-organisms, and need to be sanitised before use as fertiliser.
Management of Pathogens
Faeces contain disease-causing organisms called pathogens to a much higher degree than urine. Therefore, it is important to avoid cross-contamination between urine and faeces. Compared to conventional mixed systems, source-separation of faeces and urine in toilets will result in: • less volume of material requiring sanitisation • reduced odour and fewer flies • lower risk of pathogens leaking from the system • safer handling Organisms that can cause disease include viruses, bacteria and parasitic protozoa, as well as hookworms and other parasitic helminths. Some may lead to severe illness or even death. Others may not be the direct cause of any symptoms but could still lead to diorrhea malnutrition or increase the risk of other infections for the individual infected. To avoid the risk of being exposed to pathogens it is important to reduce contact with the excreta, and to decrease the number of pathogens in the material. Pathogens such as protozoa and viruses will decrease naturally since they are not able to multiply outside the host, but bacteria may continue to multiply under favourable conditions. As there is currently no ideal indicator organism to ensure the quality of the excreta, the guidelines focus more on treatment methods and recording parameters of importance. 98
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WHO guidelines
Soil is a natural sanitisation system for faeces, but its effectiveness is difficult to predict. Treatment of excreta is not considered necessary in current WHO guidelines if a set of barriers are maintained. These include that the persons handling the waste should have adequate protection, the waste should be covered by 25 cm of soil, and no root crops should be planted (WHO, 1989). Revised WHO guidelines are currently in production.
Primary Treatment of Faeces
The purpose of primary processing is to reduce the volume and weight of faecal material to facilitate storage, transport and secondary treatment, and to make further handling safer. This process takes place where the faeces are being deposited, either in or under the toilet. Usually the containment period is 6-12 months, depending on the size of the collection chamber. During this phase, pathogen levels will be reduced as a result of storage time, decomposition, dehydration, increased pH, and the presence of other organisms and competition for nutrients. Storage and Desiccation: Urine is directed away from the faeces to keep the processing chambers dry and the volume small. Ash or lime is added after defecation to lower the moisture content and to raise the pH- level, thus creating unfavourable conditions for pathogens. Cellulose such as rice husks or sawdust can also be used as a compostable desiccant. Material is usually kept for 6-12 months before secondary treatment. Reaching low moisture levels is highly climate dependent and the material will not always be dry enough for pathogens to be inactivated even if urine is diverted. Faeces are kept separate from both urine and water. By ventilation and the addition of dry material, the pathogen levels will gradually decrease. The use of solar heating can further increase pathogen die-off. Alkaline treatment: The addition of wood ash or lime will reduce the number of pathogens due to the elevated pH. This treatment also reduces odour and the risk of attracting flies to the toilets
Secondary Treatment of Faeces
The purpose of secondary treatment is to make human faeces safe enough to return to the soil. Secondary processing includes high temperature composting, chemical addition of urea and longer storage times. Incineration is used if a completely sterile end product is needed. Thermal composting: pathogens are destroyed if the compost is kept at an operational level of at least 50째C for 7 days. Addition of bulking material to the faeces is necessary to reach thermophilic temperatures and co-composting with organic household waste is an option. A crucial part of the treatment is the number of turnings needed for all material to be evenly heated and that further maturation of the compost is allowed. Alkaline treatment: The addition of urea, ash or lime to the faeces will help eliminate the pathogens by elevating both the pH and the level of ammonia. A pH of over 9 for at least 6 months will kill most pathogenic organisms. At a higher pH, shorter time periods could be recommended. Addition of chemicals is mainly an option in large-scale systems involving trained personnel. Storage: In areas where ambient temperatures reach up to 20째C, a total storage time of 1.5 to 2 years will eliminate most bacterial pathogens and will substantially reduce viruses and parasites. At higher ambient temperatures, storage times could be shortened to around 1 year. Incineration: This can be an option as it will ensure that all pathogens and parasites are destroyed, but some nutrients will be lost during the incineration.
Composting systems
Human faeces, or faeces plus urine, are deposited in a chamber along with organic household and garden waste, and bulking agents such as straw, wood shavings or twigs. A variety of organisms break down the solids into humus. Temperature, airflow, moisture, carbon materials and other factors are controlled to varying degrees to promote optimal conditions for decomposition. After about 6-8 months (Winblad and Simpson-Hebert, 2004), the material is usually moved to a site for hightemperature composting as secondary treatment. In a soil-based composting system, faeces, or faeces plus urine, are deposited in a chamber together with a liberal amount of ordinary soil and sometimes wood ash as well. Most pathogenic bacteria are destroyed within 3-4 months (Winblad and Simpson-Hebert, 2004) as a result of competition with soil-based organisms and unfavourable environmental conditions. Secondary treatment is as above, the sUSTAINABLE Water Resource HANDBOOK
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or as further composting storage in shallow pits for an additional 12 months. Due to UV-radiation, dryness and competition with other soil organisms, the amount of pathogens is decreased.
Treatment of urine prior to use as fertiliser
Contamination of urine with faeces considerably increases the need for urine sanitisation. The recommended treatment of urine for large-scale systems is storage. Storing at ambient temperature significantly decreases the number of pathogens in the urine. Recommended storage time at 4-20°C is between one and six months, depending on the type of crop to be fertilised. For urine that is significantly contaminated a longer storage time and/or a higher temperature is recommended. The urine should preferably be stored undiluted to provide a harsh environment for pathogens, and in a sealed container to prevent loss of nitrogen. When single households use urine as a fertiliser, there is no need for storage prior to application. The only guidelines given are that the crop is intended for the household’s own consumption, and that the last application is made at least 1 month prior to harvesting. The risk of transmission of disease via urine-fertilised crops is generally lower than between family members.
Practical recommendations on reuse
• U rine should be applied close to the ground to avoid aerosol formation. The urine should thereafter be incorporated into the soil, either mechanically or by subsequent addition of water. • For faeces transportation there should be separate equipment used for the unsanitised faeces and for the treated product. Treated faeces should be worked well into the soil, and not left on the surface. Treated faeces should not be used for vegetables, fruit or root crops that will be consumed raw. Precautions such as wearing gloves and thorough hand washing should be followed by the person handling the excreta. • A period of at least 1 month between application and harvest is recommended both for urine and for treated faeces. This will further reduce the risk of pathogens due to microbial activity in the soil, UV-radiation from the sun, and desiccation. This 1 month period also is needed for the crops to utilise the nutrients. • Urine diversion is always recommended. This reduces the amount of faecal material to be sanitised and lowers the risk for disease transmission. This also reduces odours and flies. • Faecal collection should occur above ground in closed compartments that will not leak into the groundwater or the surrounding environment. • Handling and transport systems should involve minimal contact with the faeces. • Toilet paper and material such as tampons and sanitary pads/napkins should be put into the toilet only if they are bio degradable. Otherwise, they should be treated as solid waste. • Anal cleansing water should not be mixed with urine, but infiltrated into soil or added to the greywater and subsequently treated. • Further addition of absorbent material, such as ash or lime, or a bulking agent, such as sawdust, may be needed when diarrhoea is prevalent.
Conclusion – Sanitation, Public Health And The Environment
The approach to sanitation worldwide should be ecologically sustainable, i.e. concerned with protection of the environment. This means that sanitation systems should neither pollute ecosystems nor deplete scarce resources. It further implies that sanitation systems should not lead to degrading water or land and should, where possible, ameliorate existing problems caused by pollution. More research and better designs are needed. Human excreta can be rendered harmless, and toilet designs that do this in harmony with agricultural and social customs hold promise for the future. The use of electricity from biogas on site approximates the electrical energy demand of the facilities. With help from Judy Bell and Judy Mann (Coastwatch members) Reference Design and Operation Criteria for urine-diversion Ecological Sanitation systems with particular reference to Public Health – L.M Austin; Ph D Thesis; University of Pretoria, 2000. EcoSanRes – Stockholm Environmental Institute – April 2005 100
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GE Water With operations in 130 countries and employing approximately 8,000 worldwide, GE Water brings together experienced professionals and advanced technologies to solve the world’s most complex challenges related to water availability and quality, increased productivity and cost reduction, and environmental regulations. Addressing the water crisis is a global challenge
Water is both our scarcest and most precious commodity and in trying to combat the worldwide shortage, many countries and leading organisations are pulling all their resources together in order to find meaningful solutions. GE Water, a world leader in membrane and filtration, diagnostic tools, specialty chemicals, mobile water, service, and financing is also working towards helping countries around the globe to find sustainable solutions for the water crisis. This is according to Nellie Swanepoel, Managing Director, at GE Water in South Africa. A recent international example of this was that GE Water in the USA , recognized the city of Tempe, Arizona with an ecomagination leadership award. Using GE technology, the city has expanded its water reclamation program, resulting in the reuse of an additional 2.5 billion gallons a year of water for commercial and industrial applications. Tempe’s Kyrene Water Reclamation Facility (WRF) was recently upgraded with GE’s ZeeWeed Membrane Bioreactor (MBR) technology to improve water re-use. The facility’s capacity has been doubled from 4.5 to nine million gallons of water a day, with a peak flow of 11.7 million gallons, making it one of the largest MBR plants in North America. “GE has supplied an innovative technology that helps us address one of our most difficult challenges – water shortage,” says Swanepoel. “We have to make use of every water resource that we possibly can, not only globally but locally, too. The GE ZeeWeed membranes provide the flexibility to take the waste water, and turn it into a commodity that is marketable and usable.” This outstanding project is an example of a growing trend to turn wastewater into a valuable new resource, particularly in areas like the American Southwest and Africa where water supplies are severely limited. Through its significant technologies, GE was recently awarded the top spot in the water treatment category of the Chemical Processing 2009 Readers’ Choice Awards. “GE ranked number one in the water treatment category over its competition, which is a testament to its expertise, service and advanced technologies,” concluded Swanepoel. For more information, please contact: Nellie Swanepoel GE Water T +27 16 982 3364 E nellie.swanepoel@ge.com
chapter 14: Source Directed Measures
Source Directed Measures Carin Bosman Director, Carin Bosman Sustainable Solutions
Sustainability can be achieved only if energy and resources are conserved by reducing waste and if resources are protected by the prevention and control of pollution. Section 24 of the Bill of Rights in the Constitution contains two important guiding principles with regard to pollution of water resources: it specifically requires reasonable legal and other measures to prevent pollution; and that these measures should also secure the ecologically sustainable development and use of resources (in this instance the water resource) while promoting justifiable economic and social development. The National Environmental Management Act (NEMA) was promulgated to give effect to section 24 of the Constitution, and contains the internationally-accepted principles of sustainability; applies throughout the country; and must be complied with in all actions of all organs of state. It is therefore a legal requirement that these principles must be taken into consideration as a general framework with reference to which all decisions that may affect the environment must be made. Section 2 of NEMA specifically requires that an integrated approach needs to be followed in environmental decision-making. The NEMA also outlines the need for an approach that differentiates between pollution and sustainable use, and states that a risk-averse and cautious approach, which takes into account the limits of current knowledge about the consequences of decisions and actions, must be used in decision-making. This in essence refers to the precautionary approach. Furthermore, it specifically states that waste must be avoided, and where this is not possible, the generation thereof must be minimised, and it must be appropriately managed. In addition to the above, the principles of using resources within their carrying capacity, and determining the Best Practicable Environmental Option (BPEO) are of particular importance with regard to the protection of water resources from the effects of potential pollution sources. The National Water Act (NWA) has incorporated these principles and concepts. In section 1, waste is defined in terms of the possible effect on the water resource to include “any solid material or material that is suspended, dissolved or transported in water (including sediment) and which is spilled or deposited on land or into a water resource in such volume, composition or manner as to cause, or to be reasonably likely to cause, the water resource to be polluted”. Pollution is defined to mean the direct or indirect alteration of the physical, chemical or biological properties of a water resource so as to make it: • less fit for any beneficial purpose for which it may reasonably be expected to be used; or • harmful or potentially harmful – to the welfare, health or safety of human beings – to any aquatic or non aquatic organisms – to the resource quality – to property Waste and pollution are hence not synonyms, and under certain circumstances, waste can be discharged into water resources without such discharge causing pollution. Chapter 4 of the NWA makes provision for the tiered authorisation of following waste disposal and discharge related activities as Schedule 1 uses, General Authorisations or water use licences (with existing lawful water uses being a transitional arrangement): 102
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• controlled activities – activities identified or declared as such, including: - irrigation of land with waste or water containing waste - waste or water containing waste which is generated through an industrial activity or a waterwork - intentional recharge of an aquifer with any waste or water containing waste • discharging waste or water containing waste into a water resource through a pipe, canal, sewer, sea outfall or other conduit • disposing of waste in a manner which may detrimentally impact on a water resource • disposing in any manner of water which contains waste from, or which has been heated in, any industrial or power generation process • altering the bed, banks, course or characteristics of a water resource • removing, discharging or disposing of water found underground if it is necessary for the efficient continuation of an activity or for the safety of people The aim of the NWA is therefore not to altogether prevent discharge of wastewater into water resources, or disposal of waste on land, as the discharge or disposal of waste or water containing waste are recognised as legitimate water uses, which may be authorised if they are beneficial in the public interest. General authorisations have already been promulgated for these water uses, and are aimed at smaller impacts that will have minor effects. It nevertheless prescribes best management practices to be followed by water users that discharge or dispose waste or effluents. Section 19 of the NWA, however, requires that “all reasonable measures” to be implemented to prevent, control and remediate the effects of pollution, imposing liabilities if such measures are not taken, irrespective if pollution is caused or not. There is a hence a clear distinction between “pollution” under section 19 of the NWA, and ‘sustainable use’ (which includes discharge or disposal of effluents and wastes) of the water resource under governance of an authorisation issued under Chapter 4. Pollution must be prevented or remedied, and cannot be authorised (there is no “licence” for pollution). A ‘sustainable use’ will be authorised if it is efficient and beneficial to the public interest. Also of note in this regard is that these water uses, as defined, makes no distinction between the surface and groundwater components of the water resource. Impacts on the groundwater component of the water resource hence also need to be considered in the same manner as an impact on the surface water component. This implies that point and diffuse sources of pollution can both be addressed by the authorisation regime established by the NWA. Whether a disposal action constitutes pollution, or is considered to be an optimum beneficial use (sustainable use) will depend on an integrated evaluation of the requirements of the water users (resource directed measures) and implementation of technology and measures (BPEO) controlling the pollution source (source directed measures). An approach based on the principles of a harmonised risk analysis framework should be followed in the assessment of applications to use the environment for waste disposal or discharge. Therefore, prior to authorising such disposal or discharge activities, the potential resource user will have to prove that pollution prevention and waste minimisation options have been exhausted before disposal or discharge options will be considered. Regulations will be made (in terms of s26 of the Act) to encourage reduction of wastes at source, “recycling or re-use of waste, water recovery, detoxification, neutralisation and treatment, and the introduction of cleaner technology and best management practices” and prescribing the outcomes or effects of management practices for waste treatment. All these measures are taken at the source (point of generation) of the waste, prior to such impact actually reaching the water resource, and are hence referred to as “source directed measures”. Source-directed measures are therefore closely related to waste management measures, which refers to measures implemented to reduce the effect of waste on health, the environment, or aesthetics, and to recover resources from the waste. These measures include waste minimisation, as well as waste separation, collection, transport, processing, recycling, treatment, and disposal, discharge or emission of waste materials, the monitoring of quantities of waste materials, their impacts on the environment, and implementing remedial measures where impacts have occurred as the sUSTAINABLE Water Resource HANDBOOK
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a result of poor waste management practices. Integrated Waste Management refers to the integrated planning, implementation, monitoring, and review of these waste management measures to ensure sustainability and to prevent detrimental impacts on human health and the environment, and in the context of this Handbook, the pollution of water resources. Waste management can be regarded as the process of making decisions with regard to the most sustainable manner in which to deal with a specific type of waste, and starts with the prevention of the initial production of the waste. Waste management entails both minimising the amount of waste produced and managing the disposal or discharge of the residue waste stream, and is based on two key objectives, namely: • To reduce the amount, volume or harmful nature of waste produced and to make the best possible use of the waste that is produced • To implement management measures, in accordance with the cradle to grave principle, that minimise harm to human health and risk of immediate and future environmental pollution before, during and after the waste is disposed of or discharged The principle applied is that wastes must be controlled at their sources, in accordance with the precautionary approach, so that resource quality objectives can be achieved. This applies to all types of waste (solid or liquid) and their disposal to either land or into water resources, and strongly correlates with the “waste minimisation” component of the waste management hierarchy. This hierarchy requires that measures to prevent the generation of waste and that will prevent pollution must be implemented in the first instance, thereafter measures to reduce, re-use or recycle the waste at source should be investigated, before considering applying for a water use authorisation for the disposal or discharge thereof on land or into a water resource. The NWA is not prescriptive with regard to what measures should be taken by which type of potential polluter, since it will depend on both the type of activity, and the resource quality objectives for the water resource within which the activity is conducted. The determination of measures to be taken prior to the actual disposal or discharge of the waste hence requires an integrated consideration of both appropriate source directed technologies (BPEO) and resource quality objectives. These requirements bring about significant challenges: it implies that industries must investigate cleaner production technologies that will ensure that the discharge of their effluent or disposal of their waste will be regarded as “efficient and beneficial in the public interest”. Moreover, this hierarchy of waste minimisation, prior to treatment and disposal or discharge applies to all types of waste, and the principle of separation of waste streams is critical in this regard. The principles apply equally to municipal waste streams. Investigations into separation of yellow, black and grey water in order to achieve waste minimisation, re-use and recovery prior to disposal will hopefully lead to the implementation of these measures as the Best Practicable Environmental Option in many cities in the near future. References Constitution of the Republic of South Africa, Act 108 of 1996 National Environmental Management Act 107 of 1998 National Water Act 36 of 1998 C Bosman and M Kidd ‘Water Pollution’ in Fuggle and Rabie, 2009 JA Lusher & HT Ramsden ‘Water Pollution’ in Fuggle and Rabie, 1994.
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b a l l a m - w a t e r s l o t ( p t y ) LTD ltd Complete on-site sewage disposal systems designed & supplied – for homesteads, schools, hotels, townships, etc Suppliers of “gem” on-site sewage treatment plants, “poly-rib” septic tanks, conservancy tanks, grease traps, french drain pipe kits, v.I.P. Toilet pedestals, v.I.P. Waterproof pit-liners, “ecolux” cisterns, p-trap w.C. Pans, universal toilet cabanas, wash hand basins, wash troughs, sinks, waterless urinals
“POLY-RIB” SEPTIC TANKS Since 1982, we have manufactured the genuine two-chamber septic tanks with sizes ranging from 1200 litres to an almost unlimited capacity. As our tanks are modular, it is possible to expand the capacity of the system as requirements increase. Our unique combination of septic tank and French drain has proven to be a winner, and we remain leaders in this field. ADVANTAGES • The system is compact, requiring minimal excavation • The tanks are light and easily transportable • Plug-&-Play • Available ex stock • No maintenance or de-sludging required “GEM” SEWAGE TREATMENT PLANTS Experience in the construction of large sewage package plants facilitated the design of our “GEM” on-site sewage treatment plant in 2002. This system was designed and engineered to cater for those instances where there is no municipal sewage disposal system, or where clay, dolomite or ecologically sensitive conditions exist. An added benefit of this system is that the final purified and chlorinated / ozone treated effluent can safely be re-used for controlled irrigation purposes, thereby saving precious water. We constantly strive to improve the quality of the output of the system, and now offer either chlorine or ozone as purification options. ADVANTAGES • The system is compact, requiring minimal excavation • Plug-&-Play • 4 hours commissioning time for a fully operative system • Automatic sludge return system • Proven sludge treatment process – anaerobic/aerobic • The system can be expanded to accommodate up to 65 people • Power consumption only 460W • Minimal maintenance required THIS FAMILY-RUN BUSINESS BELIEVES IN PROVIDING A QUALITY PRODUCT AT A REASONABLE PRICE, WITH AN EXCELLENT BACK-UP SERVICE. PLEASE FEEL FREE TO CONTACT US, OR VISIT OUR WEBSITE, FOR MORE DETAILED INFORMATION ON THESE AND OTHER RELATED PRODUCTS. Contact details: Telephone 012 3479151 / 3479013 • Cell: 082 4178069/082 4177821 • Telefax: 012 3479174 EMAIL: ballam@mweb.co.za • Website: www.ballamwaterslot.co.za P O Box 65399, Erasmusrand, 0165
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WATER SUPPLY AND SANITATION IN RURAL VILLAGES G E McConkey Jantech cc.
INTRODUCTION
Nearly half of the population in South Africa lives in a rural setting. For the authorities, supplying reasonable water supply and sanitation service to these communities is not an easy task as they are often some distance away from urban areas, making construction of water and wastewater reticulation economically unviable. Groundwater is the main source of potable water for these communities and these supplies need to be kept in a sustainable state or else the community is at risk. Sanitation in these communities has improved and will continue to do so as South Africa strives to achieve the Millennium Development Goals.
RURAL WATER SUPPLY
Surface water
Most of South Africa’s water requirements are provided by surface water supplies. There are 320 major dams with a total capacity of more than 32 400 million m3, which is 66% of the total mean annual runoff of about 49 000 million m3/annum. A portion of this runoff needs to remain in rivers and estuaries to support the ecological component of the reserve. The remainder is considered as a usable yield.
Groundwater
Groundwater is used extensively, particularly in rural and arid areas where surface water is inadequate. There are 6 major aquifers in South Africa; the Dolomites, Table Mountain Group sandstones, coastal sand deposits, basement granites, Karoo dolerites, and alluvium along perennial rivers. Most exploitable groundwater occurs in the eastern and north eastern parts of the country and the Western Cape, where the aquifers are concentrated. Constraints on increasing the abstraction of groundwater include inadequate water quality and over abstraction. Water quality may fail to meet user requirements due to excessive concentration of chloride, nitrate and other salts, all of which are costly to remove. Over-abstraction can result in adverse impacts on groundwater-dependent ecosystems, including estuaries, wetlands and springs. It is estimated that there are over 19 million rural people in South Africa and many of whom rely on groundwater as their only water resource. It is also estimated that more than 400 communities in the country are dependant on groundwater for domestic purposes. Although the total harvest potential of groundwater in South Africa is estimated to be about 19 000 million m3, the country utilises less than 2%. This is estimated to be about 15% of the total water use in South Africa. Approximately 85% of the water resources in South Africa are estimated to be stored as groundwater and the balance is what you see in the country’s dams and rivers. As water demand grows it is expected to exceed water availability in the next few decades. Options will need to be explored to reconcile demand and availability. One of these will be the increasing the use of groundwater. Most of the rural boreholes and well points will be supplied with a simple hand pump as there are no other power sources available in most of these areas. the sUSTAINABLE Water Resource HANDBOOK
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CHALLENGES OF WATER SUPPLY
Groundwater
Over-abstraction results in the depletion of the groundwater resources which results in the drying up of the boreholes. Over-exploited boreholes can also result in the following problems: • More expensive costs of pumping as the levels of the water drop • As a borehole dries up it can cause land subsidence • If the borehole is close to the sea and is over utilised, intrusion of seawater into the groundwater will affect the quality of the water • There is a perception that groundwater is not as reliable as surface water resources • If there is an intrusion of saline water into the water resource being abstracted, this cannot be reversed. It needs to be recognised that ground-water might be a quick-fix solution to a thirsty community but this source can also be a sustainable supply if there is an understanding of the yield of the borehole and if the borehole is managed according to its potential.
Surface Water
South Africa is not blessed with the large rivers that can be found in countries north of our borders. Most of the rivers are perennial and as a water resource to rural water users, there will always be a concern as to the sustainability of the supply.
Water Conservation and Demand Management
The water legislation that has been put into place over the past 15 years has made some of the tools available to manage our surface and groundwater. However, a lack of capacity and financial resources within the regulating bodies has led to inconsistent management and a lack of widespread enforcement. There is also a lack of understanding of the responsibilities of first, second and third tier government structures when it comes to the management of water resources, especially the rivers and streams that run through municipal areas. Water-supply organisations should strive to supply water efficiently and effectively and to minimise water losses from reticulation leakage and to promote water conservation and water demand management (WC/WDM) among their consumers. It can be said that water conservation and demand management are better managed in rural areas because there is more value placed on the commodity because it is sometimes difficult to come by.
Climate Change
Climate change will have a significant impact on the hydrology of South Africa. Already rising temperatures and the variability of rainfall have had an influence on surface waters which has increased the potential for drought in some regions and caused massive floods in others. Longer dry spells are likely to be experienced in the interior of the country with the probable effect of greater evapo-transpiration and more stressed surface waters. No development or investment decisions should be made which do not take into account the actual or potential effects of climate change on water resources.
DRINKING WATER QUALITY ISSUES
More than 80% of diarrhea cases worldwide are a result of poor water quality, a lack of adequate sanitation and a lack of good hygiene practices, resulting in 1,5 million deaths of children annually. Malnutrition is also linked to poor water quality. An estimated 50% of malnutrition is associated with repeated diarrhea, causing weight loss or intestinal nematode infections as a result of unsafe water, inadequate sanitation or insufficient hygiene.
Salination
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(DWA) from 450 groundwater sites seem to indicate a deterioration in groundwater quality from 46% samples taken and an improvement of water quality in 17% of the monitoring sites. The major cause of the deterioration of groundwater quality is as a result of over abstraction. Salination also occurs in surface waters as a result of bad agricultural, industrial, mining and urban land-use practices which add nutrients to our rivers and increase the levels of salinity.
Nitrates
Nitrates do occur naturally in groundwater through linkages to organic matter content of water which influences the dissolved oxygen content and the pH. The presence of nitrates in groundwater can also be a result of pollution from a surface source, such as sanitation systems or the use of fertilisers in agriculture. Nitrates in surface waters are also the result of bad land-use practices, especially where agricultural fertilisers are concerned. The discharge of purified sewage effluent also increases the levels of nitrates and phosphates in surface waters significantly and this results in eutrophication taking place in most of the large dams. Hartebeespoort Dam in the North West Province is a vivid example of how large volumes of purified sewage effluent and urban run-off have affected the quality of the river water.
Bacteriological Quality
Bacteriological quality of groundwater is affected by boreholes or wells being close to sanitation systems as well as in areas where animals are kept. In many rural examples the water supply from a groundwater source for domestic purposes will also be used for animals and watering troughs near the borehole to encourage the animals to stay in the vicinity of the well. As a result a build up of organic material takes place which eventually seeps into the groundwater. The bacteriological quality of surface waters is of great concern as rivers are being subjected more and more to point and non-point sources of pollution from urban areas as well as bad land-use and agricultural practices in urban areas.
RURAL SANITATION
South Africa has a number of significant programmes concerned with the delivery of water supply and sanitation, including the Community Water Supply and Sanitation programme (CWSS) of the (DWA). An increase of access to sanitation is a key component of development and poverty reduction, as it has major health benefits as well as associated social, economic and environmental benefits. Inadequate sanitation can cause several diseases which are transmitted to humans through exposure to sewage. Sanitation is a critical intervention needed to improve living conditions among South Africa’s poor. Of the 19 million rural people in South Africa, it is estimated that 12 million have access to sanitation above RDP levels. Those with inadequate sanitation facilities use bucket systems, unimproved pit toilets or the bush.
What is acceptable Sanitation?
Sanitation services in the South African context mean: • Provision of a toilet facility of a certain standard • Health and hygiene education • Correct management of domestic wastewater and rubbish
Toilet Facilities
Acceptable sanitation comes in the form of the VIP (Ventilated Improved Privy). Is a simple design that takes the normal pit latrine and adds ventilation to it so that the users are not plagued by flies and odours. the sUSTAINABLE Water Resource HANDBOOK
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Health and Hygiene
Health and hygiene are also promoted through the WASH (Water, Sanitation and Hygiene for all) programme which is also sponsored by the DWA. WASH concentrates on niches and leverage points that support existing sanitation initiatives. It can be understood that to improve the health of rural communities, it is important for them to understand the linkages between sanitation, the washing of hands and problems associated with the contamination of food and water if simple hygiene is not practiced.
Management of Greywater
It must be recognised that there are other sources of wastewater other than what might arise from toilet facilities. Greywater, which is essentially washwater can also be highly contaminated and cause community health problems. A small community does not really have washwater disposal issues as the water can soak into the ground creating problems that become more pressing and difficult to solve. Greywater can be disposed of in various ways including septic tanks, soak-aways and even through small pond systems. It must be remembered that children are always attracted to water and that they are vulnerable to major health risks when playing in areas where greywater has collected.
Management of Solid Waste
The management of solid waste is also an issue in rural communities because there are usually no services available that collect and dispose of solid waste. Small rural communities are advised to identify an area where they can dispose of their solid waste. The area should be fenced and the waste buried to ensure that health hazards not occur; e.g. the breeding of flies.
Conclusion
Target 10 of Goal 7 of the Millennium Development Goals set by the United Nations requires halving of the proportion of households without sustainable access to safe drinking water and basic sanitation. South Africa has reduced the relative proportion of households without sanitation infrastructure from 50.1% in 1994 to 27.4 % in 2007. Significant progress has therefore been made. It should be noted that the figure reflects the provision of infrastructure and does not reflect actual use if the service has been provided. The 2008 Review indicated that in April 2006, the backlog of access to sanitation infrastructure was more than 3.7 million households and that the delivery rate would have to be accelerated. Major progress has since been made with regards to the provision of basic water and sanitation services as access to basic services increased from 59 % of the population in 1994 to 94% in March 2007. The sustainable provision of water and sanitation services will always remain a challenge in rural areas because of a lack of operational and maintenance personnel. However, great strides are being made to promote capacity building and training of water supply and sanitation personnel so that this problem can be addressed. References Department of Environment Affairs. State of the Environment Report, 2005. http://www.deat.gov.za/enviro-info/ Seward P. 2007. An introduction to groundwater occurrence and management. Groundwatermatters, Department of Water Affairs, South Africa. United Nations Development Program. Mellinnium Development Goals, South Africa Mid-term Country Report. September 2008 http://www.undp.org.za Water Research Commission: Water Wheel March/April 2008 pages 16-20, 34-35 Water Research Commission: Water Wheel May/June 2008 pages 29-31 Water Research Commission: Water Wheel May/June 2008 pages 32-34
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Opinion piece Sanitation - A Matter of Dignity Sanitation refers to the equipment and systems that keep places clean, especially by removing human waste. Clearly, sanitation is about hygiene - the practice of keeping yourself and your living and working areas clean in order to prevent illness and disease. Hence, an obvious consequence of poor sanitation is an environment characterised by unhygienic conditions leading to diseases and poor health for both people and the environment. The seriousness of sanitation is thus the fact that it impacts on human lives and can causes widespread diseases and deaths. Sanitation touches the core of human lifestyle and the environment at large. Sanitation facilities such as toilets are used daily as going to the toilet is one of the most basic and frequent human acts! Without sanitation, our environment would be filthy and polluted to the extent of not being able to exploit natural resources such as water for social and economic benefits. Therefore, sanitation is simply a matter of dignity. . It’s a well known fact that it is difficult to preserve your dignity when you have no job and no home. Similarly, living in an environment without adequate sanitation facilities robs humanity of its sense of importance and value. This sense of importance and value has an impact on society’s productivity and how the environment is managed. Knowing what sanitation is and its importance, the question one would ask is: ‘why is it that there are still 2.5 billion people globally, or 38% of the world population, lacking improved sanitation or adequate toilet facilities?’ It is unimaginable to note that this statistics is in the wake of improved sanitation technologies and knowledge worldwide! It is interesting to know also that the costs of meeting the sanitation targets of the Millennium Development Goals (MDGs) are actually well-known. According to the United Nations Organisation, about US$ 9.5 billion is required to meet the 2015 MDG for sanitation alone! Is the problem with the money alone? If we had the money, can we resolve the sanitation challenge! If not what do we need and have to do to solve the sanitation problem? The answers to these questions seem very hard to find and yet they seem logical as well. Someone said, ‘if you want to resolve most of the global problems, you would first have to get rid of human beings’. I think the solution to the problem lies in this statement: human beings are the root cause of the sanitation challenges. Most countries have long developed policies, legislation, strategies and attendant implementation strategies to deal with many social and economic sectors. However, it’s astounding to note that sanitation was largely left behind. It’s only in recent years that it is receiving the attention it deserves. For the first time, a whole year was dedicated to sanitation: 2008 was declared the Year of Sanitation. The direct link of sanitation to water is the reason why it has been overshadowed whenever there were discussions on ‘Water and Sanitation’. The situation has improved and sanitation is receiving its due attention. It has now been added to the slogan ‘Water is Life’, which now reads ‘Water is Life, Sanitation is Dignity’. Sanitation is thus no longer an orphan of water, as previously referred to! Despite this improvement in recognising sanitation, current global statistics have remained astonishing:
profile • Only 62% of the world’s population has access to improved sanitation. • 2.5 billion People lack access to improved sanitation, including 1.2 billion people who have no facilities at all. • Lack of sanitation is the world’s biggest cause of infection. • At any one time, more than half of the poor in the developing world are ill from causes related to hygiene, sanitation and water supply. • 88% of cases of diarrhoea worldwide are attributable to unsafe water, inadequate sanitation or insufficient hygiene. • Of the 60 million people added to the world’s towns and cities every year, most occupy impoverished slums and shanty-towns with no sanitation facilities. • It is estimated that improved sanitation facilities could reduce diarrhoea-related deaths in young children by more than one-third. Let me re-state that the solution lies in the human beings ourselves, especially those in political leadership. There is a general attitude of indecisiveness to deal with sanitation challenges, despite visitations made to known problem sites. Such visits are usually made just prior to elections and in the early days of being in power, after which it’s ‘Out of Sight, Out Of Mind’. This is particularly common in rural and peri-urban areas where poverty, hence ability to pay for services, exacerbates the situation. The poor folks in these areas usually do not have strong political representation and voices. Where efforts have been to provide sanitation services in such areas, the issue of taking ownership over the facility comes into question as well. Continued community education therefore becomes important to ensure sustainability. However, there instances where despite educating the community, the sanitation facilities have been vandalised. The importance of sanitation given its public nature quiet evidently tell us that political leadership need to seriously start to deal with the sanitation problem in sustainable ways. This entails communicating roles and responsibilities in a manner that ensures accountability. Knowledge and technologies are abundant and must be used to ensure the dignity of our environment and society. Informed recipients of sanitation facilities are supposed to take care and ownership knowing that their own dignity is at stake. In urban areas, sanitation service providers need to endlessly communicate the various levels of service available and cost implications. An informed background ensures willingness to pay for services. However, in most developing countries partnership with Government to support sanitation programmes in indigent communities remain necessary. Sanitation is matter of dignity and therefore access of proper sanitation is a human rights issue. Sanitation is not simply a matter of providing toilets, but rather an integrated approach that encompasses institutional and organizational framework as well as financial, technical, environmental, social and educational considerations. It is recognized that it may not be affordable to provide waterborne sanitation for all, but basic sanitation must still ensure hygiene and dignity. It is also acknowledged that, at all levels, the sanitation problem is related to socio- cultural, educational and institutional issues, with the lack of appropriate and inadequate guidelines being contributory factors. In addressing sanitation backlogs, it is critical to respond to the needs of communities, which must be linked to improved hygiene awareness. For people to benefit from sanitation improvements, everybody must understand the link between their own health, good hygiene and toilet facilities. Communities must be fully involved in implementations and integration with other municipal services such as water must be ensured.
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Recreational Use of Water With money we can build roads and cities. But no amount of money can build a naturally functioning river with cool, clear, drinkable water.
Di Dold Environmental Co-ordinator WESSA: KZN Region
INTRODUCTION
Humans can live without electricity, even food for a few weeks, but without water we cannot survive. Water is a natural resource that is recycled through natural systems in a manner that cannot be influenced. Simply put â&#x20AC;&#x201C; we cannot make water! With climate change, we are seeing the western half of our country progressively becoming more arid, with erratic rainfall. Many areas have been suffering the effects of drought for years. Supplies of water for towns and cities have dried up and water has to be sourced from other areas. Human activities have also changed the springs, wetlands, rivers and estuaries so that they no longer supply water at a rate and of the same quality on which we have been previously able to rely. Evaporation rates in South Africa are high, which means that much of what we store in dams is lost. The answer is not to build more dams, on stream, as they have previously been built. On stream, means that the river flows into the dam, bringing with it all the sediment carried by the river. This fills the dams with sediment reducing the storage capacity. We have to find innovative ways of storing water in a way that reduces losses and ensures that the sediment reaches the estuaries and beaches â&#x20AC;&#x201C; where it is necessary for the natural functioning of these systems.
Waste Streams and Treatment
The water we remove (abstract) from rivers and dams for use is treated with chemical processes to achieve water that meets drinking water standards. Unfortunately much of this water is then wasted through leaking pipes, pumps and taps. In some municipalities, more than half of the treated water is wasted before it can be charged for, so the cost of the water is not recouped. We are polluting our precious water supplies, by discharging sewage and industrial wastewater into rivers, estuaries and the sea. If these effluents are not treated or leak before they reach the treatment works, they have the potential to impact the water resources to a point where water can no longer be used and treatment costs become prohibitive.
O&M and Housekeeping
We need to ensure water is used wisely by not wasting it and ensuring we do not pollute water supplies. Aquatic ecosystems need to be conserved to ensure that they can continue to provide us with water of a good quality. This must therefore identify, delineate and protect springs, wetlands, rivers and estuaries. Where these natural assets have been damaged or compromised, they need to be rehabilitated and restored to ensure they continue to function. This could include removing alien invader species of fauna and flora, restoring the indigenous species, removing rubble and litter, organising a monitoring programme to ensure that action can be taken when there is early warning of pollution. Wetlands and estuaries are essential for attenuating the effects of floods, so high water marks need to be respected and no development should take place within these flood plains. Stormwater also needs to be managed to prevent flooding. Hardened surfaces increase rain runoff during storm events, which increase the likelihood of flooding. Settlements, towns and cities need to ensure they have sufficient absorbent surfaces to minimise the effects of heavy rainfall. This can be done by establishing sufficient, linked open spaces to increase biodiversity, using indigenous vegetation. Fences and walls need to be minimised to allow for corridors for movement of wildlife, rather using indigenous vegetation with thorns to act as barriers between properties and prevent unauthorised access. Absorbent alternatives to tarred parking areas and pavements and roofing need to be explored to allow for reduced runoff contributing to localised flooding during heavy or prolonged rainfall. the sUSTAINABLE Water Resource HANDBOOK
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Stormwater should not be diverted to the sewer systems, as this causes overflows during rainstorms, resulting in pollution of water resources. Wetlands and river meanders should be restored to attenuate flooding from rainstorms, these natural assets can assist us in adapting to climate change. In fact, restoring and enhancing them should be a priority.
Challenges and Effects
Water and waste issues need to be managed in an integrated manner to ensure that our efforts do not have unanticipated consequences. The new Waste Act makes reference to the implementation of the Waste Hierarchy. This means that whether we are at home, work or play we need to look at what we do to avoid generating waste. We can look at different ways of doing things or changing the raw materials used. If waste is generated, ways to minimise the amount by reusing, recycling or even by recovering water or energy, should be investigated. Ways to reduce the risk associated with this waste if it is harmful to people or the environment then need to be explored. Only after this has been done, can we think of disposal to the environment, to air, water or land. Currently, most people simply discard that which we no longer need as there is little incentive to do differently. We also do not understand or pay for the true cost of waste. Everything we do has an impact on the environment and we need to continually work to reduce our personal footprints, whether at home, work or play. It is the cumulative effect of all our wastes that is resulting in the changes we are seeing in our planet. Waste avoidance or prevention is the answer, as treatment can only reduce the risk, it cannot remove all impacts. Our sanitation systems rely mainly on water to convey our waste, as water is scarce, so we need to start finding ways to deal with waste without using water for transport and dilution.
Eutrophication
Many rivers, dams and estuaries are accumulating the “nutrients” from our waste to a point where they become classified as nutrient-rich. This results in algal blooms, which are able to take advantage of these nutrients to flourish. Once the algae have died they use up the oxygen during decomposition, which then causes the aquatic life to suffer and eventually die. Fish and other aquatic animals need oxygen in the water to survive. Fish kills have become so common that we no longer seem to react to them. It is very difficult and extremely expensive to reverse eutrophication and the main causes are sewage inflows (raw and treated), as well as agricultural run-off from fertilisers and industrial effluents rich in these nutrients.
Human Health
Many communities rely on “raw” water and suffer from diseases such as gastro-enteritis and cholera, which are debilitating and potentially fatal. Children, the elderly and those people with compromised immune systems are most at risk, especially in areas where health care facilities are few and far between. It is becoming more expensive to treat water for use and in many communities where basic services, such as clean water and sanitation are not being provided reliably, people are getting sick and children are dying from diseases that are preventable. Water should therefore be supplied equitably and not wasted or used illegally.
Best Practices
Natural assets include springs, streams, rivers, wetlands and estuaries, while the built assets comprise the water and wastewater works, the sewerage systems, dams, reservoirs and other structures. The objective is to maximise the state of the natural assets, so that the cost of operating and maintaining the built assets is minimised, allowing for periodic non-conformances to be quickly assimilated and be rendered harmless. It is ironic that nature has provided us with all the tools to store, clean and process our water, but that humans determinedly destroy these ecosystems and then spend millions of rands building treatment plants to do what nature was doing all the time. By investing in the natural assets, we will be able to improve the health of communities, currently affected by poor quality and supplies of water and ensure that our people do not contract diseases from recreational pursuits in our rivers, dams or estuaries and that our tourism industry is not adversely affected in the same way. South Africa needs to develop in a way that provides opportunities for all citizens.. We need to 116
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find a way to assist local authorities to provide services to their constituents, while ensuring that the ecosystems that support our lives are able to provide the goods and services on a sustainable basis. People can help to prevent illegal and wasteful uses of water, as well as activities that pollute our water supplies or render them more expensive to treat. We can also restore and enhance the aquatic ecosystems to provide cost effective goods and services again. We all need to bear in mind that everything that is discharged into a water course, however small or insignificant, will, in some way, impact on the whole system. Further, we need to always bear in mind, that everything discharged into the whole length of a river system, eventually ends up in the marine environment. This has a direct impact on our coastal populations and our tourism industry. The continued health of rivers, marine and estuarine systems, and the human systems that depend on them, relies on the maintenance of high-quality habitat. These natural areas provide essential food, cover, migratory corridors, and breeding/nursery areas. For humans, they provide an economic basis for tourism, and ecological functions, far beyond aesthetics. Estuaries and wetlands protect water quality, riparian and coastal wetlands provide storage for excess water during flooding, as well as support valuable fisheries. Barrier beaches and wetlands act as buffers protecting humans from coastal storms. (Demetriades and Forbes, 2008)
Salination
Salinity is the measure of the total concentration of ions or mineral salts in the water column. Seawater contains 35g of salt per litre of water. Salinity in an estuary will fluctuate depending on freshwater inflow and mouth state. It is one of the major drivers influencing estuarine species composition, distribution and abundance. It is also an important driver of the chemical environment, particularly influencing dissolved oxygen levels such that increasing salinity decreases the dissolved oxygen potential. (Demetriades and Forbes, 2008)
Water Conservation and Demand Management
Re-use
The re-use of water is already being applied in Namibia and in some areas on the Highveld. It is being actively explored in KwaZulu-Natal as a very viable solution to our water shortage problems.
Hardware:
Urine Diversion Toilets Waterborne sewerage has been popular for some 200 years. But it is hardly a solution, especially in a water scarce country. Other solutions such as urine diversion and dry composting are being explored. Urine diversion toilets work so that the acidic urine, when added to the faeces, does not inhibit the natural breakdown processes of the bacteria. To date some 55 000 toilets have been installed in the greater Durban region. However, these toilets are not considered “mainstream”, so in the more affluent areas, water borne sewage is the norm and the problem of pollution and declining supplies continues. Biodigesters Biodigesters break down organic waste and produce methane, a gas that is excellent for cooking, that is also free! Biogas could be used to generate electricity, as is common in many waste water plants in the world. Local Authorities are under increasing pressure to both reduce electricity demand as well as to diversify and increase their own generation of electrical energy. In particular, wastewater treatment facilities pose a serious risk as far as human health is concerned, should the power supply “go down” – all the pumping and mixing requirements cannot then be met, with the net result that non-compliant water is discharged to rivers and the broader environment. The use of electricity from biogas on site approximates the electrical energy demand of the facilities. With help from Judy Bell and Judy Mann (Coastwatch members) Reference: Demetriades and Forbes, 2008 Estuaries of Durban, Kwazulu-Natal, South Africa, 2009 Report the sUSTAINABLE Water Resource HANDBOOK
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Instituto Superior De Relações Internacionais An Overview
The Higher Institution for International Relations - ISRI was established in 1986 through the Decree 1/86 issued by the Mozambican Cabinet of Ministers as a public institution for the training of diplomats and experts in international relations. As one of the key institution in the country on international relations matters, ISRI has made remarkable and pioneering contributions in the promotion of the studies of international relations as an academic and research field in Mozambique. Due to the importance and demand of high patterns of public administration in Mozambique, ISRI introduced in 2003 a course of governance, more specifically on public administration, to meet adequately the challenges imposed by the dynamic of the Mozambican State. Our Organization Headed by an executive and representative Chancellor, ISRI comprises five divisions: • Chancellor’s Office • Center for International Strategic Studies – CEEI • Academic Division • Scientific Division • Finance and Administration Division Courses Provided ISRI provides graduate courses in two main areas: Public Administration and International Relation and Diplomacy. International Relations Area Bachelor and Honors in International Relations and Diplomacy – This is a four year course including a Dissertation. Master in International Relations and Development – This is a two year course including a Dissertation. Public Administration Area Bachelor and Honors in Public Administration – This is a four year course including a Dissertation. Master in Public Administration and Development – This is a two year program. Master in Management for Development – This course comprises four diplomas: Diploma in Social Management and Public Policies. Diploma in Monitoring and Evaluation of Social Programmes and projects. Diploma in Public Management for Territorial Development. Diploma in Public Management Focused in Gender. Honorific Titles ISRI grants Emeritus Professor Tittles and Honoris Cause, Doctorates to lecturers, Scientists and Eminent personalities who distinguish themselves in the field of teaching, Scientific
profile Research, Science, Humanities and Culture, in general terms or, personalities who may have provided relevant services to humanity, to the Nation or to ISRI. Our Vision Our vision is the empowerment of the Mozambican professionals, improving their concepts on time management, team work, integrated developmental planning and nurturing knowledge and abilities relevant for public administration reform already put in place by the Mozambican Government. Further the vision is to prepare competent diplomatic human resources to face the challenges of a global world. Our Objective: Our objective is to contribute in capacity building of the existing professionals and to create a competent public sector, diplomats and researchers in international relations and public administration areas. Our Mission: Our mission is to develop and disseminate analysis on cultural socio economical processes, politics in Mozambique, the Southern African Region as well as of the international system. Our Research Fields Include: • Foreign Policy Studies • Peace and Security Studies • Economics and Developmental Studies • Sociopolitical and Cultural Studies Integration in the Society SRI’s integration in the Society entails the dissemination of its undertakings and outputs, collaboration with Government, Public and Private Institutions. This process relates to strengthening and maximizing the gains already attained, by providing a positive and constructive image on a permanent basis, thus adding value to its role as a producer, disseminator and user of science. Contact details: University campus Rua do Grande Maputo Bairro do Zimpeto, Q88 Maputo, Mozambique
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Agricultural Use of Water A S Roux Pr Eng Director: Sustainable Resource Management Department of Agriculture: Western Cape
When the well is dry, we learn the worth of water – Benjamin Franklin Introduction
Although about 70% of Earth’s surface is water-covered we can use only 1% of that – 97% is in the oceans and 2% within the ice caps of the poles (USGS). All the fresh water on earth will fill a droplet 1 400 km in diameter, in comparison to the earth diameter at the equator of 12 756 km (About.com: geography). This 1% of water must be shared between all the different water user sectors such as agriculture, domestic use, industries, mining and the environment. “South Africa is one of the water-scarce countries of the world, with an annual average rainfall of 480mm compared to a world average of 860mm. Rainfall is furthermore highly variable in different years, unevenly distributed during the year and over the various surfaces of the country” (Du Plessis 1998). Our average annual rainfall ranks us as the 27th driest country in the world out of a total of 194 countries. The 26 countries ranked drier than South Africa are mainly situated within the Sahara-desert area in North Africa and the Middle East. (Pansegrouw, 2005). Our average evaporation can be as high as 2 000mm per annum, which is more than four times our rainfall. Agriculture is the largest water use sector with a consumption of approximately 50% of the total water use in South Africa. Our cities use approximately 18%, our industries 10% and our mines are responsible for 3% of the water use. (Pansegrouw, 2005))
Water demand management
Water resource management in South Africa is shifting increasingly from supply management to demand management i.e. optimise the existing water usage before new resources are being developed. Demand management will play an increasingly important role in managing our water resources in the future, especially in view of the expected impacts of climate change on the rainfall patterns and intensities in our country. Irrigation will have to compete increasingly on an equal basis with the other water user sectors for the available water resources. It is unlikely that irrigation will get an increased allocation of water due to the current over allocation of water in catchments areas. Demand management within the agricultural sector presents the opportunity to save water for the expansion of irrigated agriculture to supply in the ever increasing demand for food production. To promote efficient use of irrigation water usage it is imperative that irrigators pay water levies based on their actual water consumption and not on their water allocations (hectares scheduled) or on the irrigated areas. This will provide an incentive to save and use water more efficiently, which in most cases goes hand in hand with an operational and/or capital cost to be incurred by the irrigator. This highlights a very relevant problem of accurate measurement of irrigation water. As irrigation water is often not purified, the impurities in the water, i.e. leaves, twigs, frogs, etc., produce challenges to water metering in terms of reliable, effective and affordable water meters. Although the Water Act, 1998 stipulates that all water used should be measured, practical and financial problems lead to unmeasured irrigation water in most of the abstraction points. However, the law is not the only reason to install measuring devices. A project funded by the Water Research Commission (WRC) (TT248/05) shows that there are also benefits related to practical water management, including accurate accounting and good records which help allocate equitable shares of water between competitive users. Moreover, it provides the farmers with information needed to achieve the best from their irrigation water while reducing the negative environmental impacts. By reducing their cost of water as an input, farmers can also compete more readily with other producers in today’s global market. (Water Wheel) the sUSTAINABLE Water Resource HANDBOOK
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The cost of water should, as in the case of all water user sectors, reflect the relative scarcity of water in the specific area. This important economic principle is unfortunately seldom applied in the water tariffs levied in South Africa. Water demand management can also be achieved through improved irrigation methods. Drip and micro irrigation can save water if it is applied correctly and the soil properties and crop water demand are taken into account. It is also very important that the required attention is given to the operation and maintenance of the irrigation systems. A properly managed and maintained flood irrigation system can be more effective than a badly operated and maintained micro or drip irrigation system. Effective utilisation of agricultural water can be achieved only through optimally operated and maintained irrigation systems and not necessarily just through the most technologically advanced system. Irrigation scheduling based on sound scientific information can be a very effective water demand management tool. Irrigation scheduling refers to providing the correct amount of water to the plant, in accordance with the crop water requirement at the specific phenological stage of growth and taking into account the water retention properties of the specific soil. Soil moisture can be determined by using scientific instruments such as tensiometers or equipment that measure the actual soil moisture at different depths in the soil profile. Irrigation scheduling should be based on this in-field measurement data. It can prevent over-irrigation and thus water wastage as well as result in the production of high quality crops. The measurement of soil moisture at certain pre-defined depths, can provide valuable information, especially in cases where the aim is to put the crop under stress during certain phenological stage of growth to enhance the quality of the crop produced, such as certain red wine cultivars. This irrigation technique is referred to as regulated deficit irrigation and can lead to smaller pips, resulting in an increased ratio between the area of skin and the fruit within the grape pips. The design of the appropriate irrigation system also plays a vital role in the optimal utilisation of irrigation water. Care should be taken that only properly qualified designers, whose irrigation systems comply with the applicable norms and standards, are used. The SA Irrigation Institute can provide guidance in this regard. Another important water demand management tool in the agricultural sector is water loss control. Certain irrigation schemes function well but there are also those where only 30% of the water released from major storage dams reaches the root zone of the crops. Conveyance losses of 30% occur between the dam and the farm boundary in cases where the river as conduit, or canals constructed many decades ago with major leaks, are used. Losses from on-farm storage and during the irrigation process can be as high as 40% (MBB). Although this water is lost for the specific agricultural application, it often becomes available again to be utilised by the ecosystems of our rivers. These losses can be reduced by lining earth canals with concrete or replacing canals with pipelines. The practical aspects such as hydraulic gradients that cannot be accommodated within the layout and slopes of the existing infrastructure, as well the economic viability, often prevent the implementation of these prospective water saving solutions. Cracks in concrete canals and other reasons for water losses should thus be identified and dealt with on a regular basis as part of an effective maintenance programme of the irrigation distribution infrastructure.
Water Quality
Disposing of waste in an environmentally sustainable manner is an ever increasing challenge, causing major problems in South Africa. The rapidly expanding population and increased migration of people to the cities and towns exacerbates the problems, especially with the limited number of technically trained staff available in local authorities to deal with the challenges. Waste water from industries, mines and the defused return flows from agriculture, add to the water quality problems experienced in our streams and rivers. Increased environmental awareness necessitates the sustainable disposal of liquid and solid wastes. The limited amount of available water resources in South Africa resulted in the current policy that it is required to utilise effluents as an integral part of the water supply. Effluent producers are therefore required to return effluents to the catchments from which they originated unless authorised to deposit it to catchment in which it is generated (Water Act of 1956; National Water Act of 1998). Since most effluents are, however, less suitable to users than the source from which it originated, producers are required to purify their effluents to acceptable standards prior to returning it to rivers or streams 122
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as per their authorisation. It is often not possible to enforce this requirement for various reasons and for these cases a licence of exemption (or permit) is issued by the Department of Water Affairs which allows the discharge of effluent to a specific piece of land. Urbanisation of people from the rural areas to towns and cities create major challenges in terms of the supply of water and sanitation facilities. The increased pressure on existing water and sewage purification plants and the required upgrading of infrastructure can often not be dealt with within the capacity (technical and financial) of the local authorities, resulting in water of a lesser quality than required (and stipulated in their permits), being discharged to rivers and streams. This has a major impact on the water quality of the rivers and on potential water users downstream of the discharge point. This is specifically relevant to farmers using the water in the river for irrigation of food crops and fruit for the export market.
Climate Change
The exact impact of climate change on agriculture in South Africa is still uncertain, but here are a few facts impacting on agriculture (Fact sheet): • “Climate change is nothing new; it’s all happened before. ”The answer is, yes, but never in the same way nor to the same degree. • Human-induced climate change will cause this level to be exceeded sometime in the next 50 years. Further increases into new temperature territory will continue for several decades if we do not curb greenhouse gas emissions. The cool Earth to which most of our natural species and existing farming practices has evolved will become warm enough to be outside the evolutionary experience of many species and unable to sustain current farming practices. • Modern industrial agriculture is one of the biggest contributors to the rapid advance of humaninduced climate change. • The increase in frequency and extremity of natural disasters can lead to erratic rainfall patterns resulting in extreme droughts and/or storms and floods and the reduction on quantity and quality of groundwater and the recharge rate. Weather systems are very complicated and need to be understood when managing our water resources and when we deal with the probable effects of climate change on the agricultural sector. The forward planning for adaptation need to take the following aspects into account: • Improve coping strategies to deal with the effect of climate change • Improve mitigation strategies to minimise the impacts on agriculture • Improve our resilience to enable agriculture to recover speedily after extreme climatic events In order to achieve the above, it is very important to invest in the scientific capacity and grow centres of expertise in South Africa that can continuously update information and climate change predictions for the different parts of South Africa and to engage in communication between science and the various stakeholders to ensure that the available information reaches all role-players and that they understand the implications thereof (Schulze, 2009). References US Geological Survey’s (USGS): Water Science of Schools web site. Http://ga.water.usgs.gov/edu About.com: Http://geography.about.com/library DU PLESSIS, H.M., 1998. South Africa a water scarce country. Paper read at the Fertigation Symposium of the Fertilizer Society of South Africa, Pretoria, 1998 PANSEGROUW, P PROF, July 2005: NMMU, Personal comments. Water Research Commission (WRC) Report No TT 248/05: Guidelines for Irrigation Water Measurement in Practice WATER WHEEL, September/October 2005, Volume 4 No 5. Murray, Biesenbach & Badenhorst (MBB) Consulting Engineers Incorporated. 1997. Towards an Irrigation Policy for South Africa. Summarised results of irrigation workshops held in the Western Cape during May 1997 Climate Change Fact Sheet: Cape Nature and Department of Agriculture: Western Cape 2007. SCHULZE, R PROF, October 2009: UKZN: Personal comments National Water Act of South Africa. 1998 (Act 36 of 1998). Department of Water Affairs and Forestry. Water Act of South Africa, 1956 (Act 54 of 1956): Department of Water Affairs and Forestry. the sUSTAINABLE Water Resource HANDBOOK
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AMATHOLE DISTRICT MUNICIPALITY – A CASE STUDY FOR A WATER SERVICES AUTHORITY
Introduction The Amathole District Municipality (ADM) is one of six district municipalities located within the Eastern Cape Province (EC). With a population of 1,7 million people, the ADM has 27% of the Eastern Cape population. The district has eight (8) Local Municipalities (LMs) under its area of jurisdiction with a geographical spread of 23 577.22 km2. The district encompasses the two former homeland areas of Ciskei and Transkei, where 70% of ADM’s water and sanitation backlog is situated within the latter area located in the Mbhashe and Mnquma local municipalities (north-east of the Great Kei (Inciba) River. In July 2006, ADM took over the function of Water Service Provider in Mbhashe, Mnquma, Nkonkobe, Great Kei, Amahlathi and Ngqushwa Local Municipalities and was thus responsible for the operations and maintenance of all water and sanitation schemes in these areas. The ADM entered into a memorandum of understanding which was extended further in July 2008 and again in July 2009 effectively appointing Amatola Water to increasingly supply bulk water services in all the urban areas within the district. Whilst this arrangement leaves the ADM’s Water Services Authority in charge of the overall management of the provision of safe water to the ADM’s customers, this agreement has also assisted the ADM operations and maintenance unit in focusing on the reticulation services and customer care. The ADM also centralized the financial services for water and sanitation as from 1 July 2006 and established Customer Care and Service Centres in all local municipalities, in order to bring services closer to communities. Responsibility of ADM as WSA ADM as Water Service Authority has a duty to all customers or potential customers in its area of jurisdiction to progressively ensure efficient, affordable, economical and sustainable access to Water Services (Water Services Act, Section 11). Currently the ADM provides water services to 85.69% of the population (834 358 people, at RDP standard or better). Thus the water backlog stands at 14.31% or 139 336 of the population. Currently the ADM provides safe water (such as a handpump, windmill, or protected spring) to a further 6.35% or 61 902 of the population with a backlog of another 9.35% (99 098 people). The ADM currently provides 31.6% of the population (or 307 687 people) with sanitation services (either waterborne or VIP toilets), and has a large backlog of 68.30% or 666 007 people who do not yet have sanitation services. The shortfall from the available MTEF/MIG funding is approximately R1,3 billion, as ADM is currently spending approximately 100% of MIG funding on water and sanitation projects.
profile Water Infrastructure Profile Many of the treatment facilities and associated water schemes that the ADM has inherited are very old [especially those associated with the older towns in the district] and have not been upgraded or refurbished for many years. This has resulted in a huge refurbishment backlog for which the ADM does not have the financial capability to address. Over 80% of consumers in the district are considered indigent and therefore no Municipal Manager, Mr Vuyo Mlokoti and Director of Engineering Services, revenue is generated from these Mr Nico Jonker, together with one of the Blue Drop Awards. consumers. In 2006 the ADM stopped collecting levies and therefore has become almost totally grant dependant. The equitable share and levy replacement grant only provide sufficient funding for operations and maintenance, but the backlog in refurbishment remains unaddressed. The problem has further been exacerbated by inappropriate design / construction methods or insufficient user education In many of the small towns, services have been improved and extended to the evergrowing population without the water resources issue and bulk infrastructure having been adequately addressed. This has resulted in major water outages which have been exacerbated by the severe drought that is currently being experienced in the area. Water Demand Management would be one way of addressing some of the issues mentioned above. Large amounts of water are assumed to be lost through leaking toilet cisterns and taps in indigent households [who donâ&#x20AC;&#x2122;t pay for water â&#x20AC;&#x201C; so no incentive to conserve], but without the necessary financial resources and technical expertise to effect repairs on a large scale, this solution still remains a theoretical one for the ADM. In essence the ADM is faced with a major challenge if not managed properly. With water and sanitation infrastructure valued at about R3 billion, and with very little financial ability to effect the necessary refurbishment works, the ADM will not be able to maintain a sustainable water supply to its communities or prevent contamination of its river resources from its sewage networks and waste water treatment facilities. ADM has submitted a status report with clear short, medium, and long term interventions required to DWEA as the sector leader to address the problems. ADM wins Blue Drop Awards In spite of all the challenges, the ADM in partnership with Amatola Water won 3 Blue-Drop awards in May 2009 at its Sandile and Peddie Kings Lynn Water Treatment Works and another smaller plant at Peddie. The Blue Drop Awards are a Department of Water Affairs initiative where water treatment works need to comply with 95% of the weighted criteria in the biannual assessments for drinking water. The ADM is hard at work to try and improve on this achievement for next year. For further information, please contact: Director of Engineering Services, Amathole District Municipality, P O Box 320, East London, 5200; tel +27 (0)43 7014000; fax +27 (0)43 742 0337; email: info@amathole.gov.za; website: www.amathole.gov.za
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MANAGEMENT OF INDUSTRIAL WASTEWATER JA Clayton, Pr. Eng. Managing Director Project Assignments (SA) (Pty) Ltd
INTRODUCTION
South Africa has a broad range of industries, including diverse activities such as mining and metals processing, oil and gas, bulk & speciality chemicals, pulp and paper, food and beverage, textiles and pharmaceuticals. Being a developing country, the expansion in some sectors is rapid, presenting serious challenges in terms of protecting our already stressed water resources. Water is key to the livelihood of South Africa business and hence the correct management of water within our industrial sector is crucial to future healthy economic growth. This chapter deals specifically with wastewater originating from our industries and provides some guidelines on how to manage it. Topics include contaminant types, treatment options, appropriateness of the technology and typical design steps.
Industrial wastewater contaminants
The composition of the wastewater clearly depends heavily on the industry from which it originates. Typical contaminants would fall into one or more of the following categories: dissolved organics, suspended solids, priority pollutants (e.g. phenols), heavy metals, colour, nutrients (nitrogen and phosphorus), oil and grease, refractory compounds, volatiles and aquatic toxicity. Each of these pollutants, if untreated, has a different effect on the receiving water. Excess organics will lower the dissolved oxygen level of the receiving water, threatening aquatic life and plant growth. Suspended solids will form sediments and scums, which in turn will also deplete oxygen and produce noxious odours. Priority pollutants and metals can cause certain taste and/or odour problems in the water; in some cases they are carcinogenic over a prolonged period. Colour pollution is an aesthetic issue, and nutrients such as N and P will promote eutrophication, stimulating the growth of undesirable algae. Refractory compounds are unbiodegradable, oil and grease result in unsightly scum, volatiles lead to odour and certain contaminants are simply toxic to aquatic life. Depending on the type of pollutant, the treatment process should be selected accordingly and a certain effluent may require a combination of unit operations to achieve the correct final effluent quality.
Treatment options
Waste minimisation
A great deal of capital expenditure on an end-of-pipe treatment solution can be saved by critically examining the sources of waste within a facility and then trying to minimise their discharge. This can be achieved through improved management of materials and operations (e.g. substituting toxic materials with those less harmful to the environment), modifying equipment (to be more efficient and produce less waste), alter production process (e.g. allowing segregation of polluting and nonpolluting streams) and implementing recycling and re-use schemes (e.g. closed loop systems). Not only do such practices lessen the load on the environment, but they also often improve an operationâ&#x20AC;&#x2122;s profitability through reduced loss of product.
In-plant treatment
Where certain streams within a factory or process are rich in contaminants such as heavy metals, pesticides and other toxic compounds, they must be treated at source, to prevent an inhibitory effect on potential downstream biological stages. Removal of specific pollutants from a concentrated source is also more cost effective and easier than dealing with a larger, more dilute stream. the sUSTAINABLE Water Resource HANDBOOK
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Heavy metals require some form of oxidation or reduction, followed by a precipitation and separation (filtration or settling) step. Organic chemicals would need to either undergo chemical oxidation, adsorption, ion exchange or reverse osmosis treatment. Volatile organics should be removed either through air or steam stripping. The treated streams can be routed either to final disposal or further treatment.
Primary treatment
Primary treatment removes solids and oils, neutralises excessive acidity or alkalinity and prepares the effluent for either further downstream treatment (biological or chemical) or for final discharge. Unit operations include flow equalisation, acid or alkali dosing, hydrocyclones, static or rotary screens, flotation and flocculation/sedimentation. In several local food factory effluents it has been observed that up to 50% of the Chemical Oxygen Demand (COD) is particulate in nature and can thus be removed before any further treatment. Another good example is effluent from a local explosives manufacturer, containing nitrocellulose, wood fibre and TiO2: through coagulation and flocculation with Al2SO4, it is possible to remove about 35% of the COD.
Figure 18.1: Rotary wedgewire screens for the removal of suspended solids from potato wastewater.
Figure 18.2: Clarifier for settling of fine starch particles from potato wastewater.
Biological (secondary) treatment
If the effluent contains biodegradable organics, a variety of biological unit operations are capable of significantly reducing the Chemical Oxygen Demand (COD). While there is no absolute cutoff, medium to high organic strength effluents (COD nominally above 3 000 mg/l) are often most economically dealt with anaerobically, whereas medium to low strength effluents (below 3 000 mg/l) are better treated aerobically. In South Africa, popular aerobic treatment options include aerated lagoon systems (where sufficient land exists), the conventional activated sludge (AS) configuration plus clarifier (with or without anaerobic and anoxic zones for N and P removal), the sequencing batch reactor (SBR) and the membrane bioreactor (MBR). The latter two technologies do not require separate sludge clarifiers and are thus more compact than conventional AS; specifically, the MBR has the potential to produce high quality effluent, suitable for re-use.
Figure 18.3: Typical MBR reactor configuration (left) with membrane chamber in foreground. Membrane bundles (right) are assembled in modules for submergence into membrane chamber. (Pictures courtesy of Koch Membrane Systems).
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Other emerging aerobic technologies for industrial effluent are the moving bed biofilm reactor (MBBR) and the HYBACS process. In the MBBR, a biofilm grows within engineered plastic carriers that are suspended and thoroughly mixed throughout the water phase. The MBBR system is able to withstand high industrial effluent loads and has a small footprint. The HYBACS process is a combination between rotating mesh disc fixed film technology and conventional activated sludge. The result is a works that has a footprint up to 40% less than conventional AS and uses 50% less energy, with full nutrient removal.
Figure 18.4: HYBACS process for industrial effluent treatment, utilising an enhanced Bacillus culture. A fixed biofilm is established on rotating mesh discs (left) followed by activated sludge reactors (right). (Pictures courtesy of Bluewater Bio).
Another interesting variation on the conventional AS process for industrial effluent is the PACT configuration (by DuPont and Siemens), where powdered activated carbon is added to the activated sludge system to buffer the biomass against toxic organics and to adsorb certain refractory compounds. Anaerobic treatment can be effected in lagoons (where space allows) or in purpose-built reactors. For an effluent volume of 1 Ml/d and a COD of 4 000 mg/l, an anaerobic system will use 224 kWh/d versus 2240 kWh/d for an aerobic set-up (based on 80% COD removal). Sludge production for the anaerobic option is 96 kg/d versus 640 kg/d for the aerobic one. The anaerobic system will produce biogas containing about 340 kW of energy. These figures illustrate that where anaerobic treatment is practical, it has distinct advantages over an aerobic equivalent, a difference that becomes more pronounced as the effluent strength increases. It should, however, be appreciated that if the final effluent is to be discharged to a local watercourse, secondary aerobic polishing would be required. Both low and high rate anaerobic reactor configurations exist, the selection often being made based on the anticipated ease of treatment for a particular effluent, together with its biodegradability.
Figure 18.5: Different options for anaerobic reactors: high rate Internal Circulation (IC) reactor on left (nominally 20 kg COD/m3/d) and low rate Upflow Anaerobic Sludge Blanket (UASB) reactor on right (nominally 10 kg COD/m3/d). (Pictures courtesy of Paques BV).
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Tertiary treatment
The most common form of tertiary treatment is filtration to remove remaining suspended matter from upstream biological processes or following coagulation in a physical-chemical treatment. This can be gravity or pressure filtration. Typical granular media are sand, anthracite and other metal oxides. Regular backwashing is an important feature. Microfiltration or ultrafiltration may also be employed for solids removal and may be used as pre-treatment if reverse osmosis is intended. Another form of tertiary treatment is the removal of colour and residual refractory pollutants by use of ozone or other suitable oxidizing agents. Treatment with granular activated carbon (GAC) may also be necessary. In certain cases, electrodialysis is useful to remove various ionic species. Some industries with high water usage are targeting zero liquid discharge (ZLD) and to achieve this, a combination of membrane and thermal processes can be used: reverse osmosis to complete the tertiary treatment, with the brine undergoing crystallisation. The crystal slurry is then dewatered in a filter press. The thermal treatment can consist either of a brine concentrator, a crystalliser or a horizontal spray film evaporator.
Figure 18.6: Example of tertiary treatment to achieve zero liquid discharge: brine from a reverse osmosis unit is passed to a crystalliser. The resulting sludge is dewatered in a filter press. Clean water is available for re-use in the process or elsewhere. (Pictures courtesy of Aquatech).
Prior to discharge to the receiving water body or for re-use, disinfection is often required. This may take the form of simple chlorination, chlorine dioxide, ozonation or the application of ultraviolet radiation.
The importance of appropriate and sustainable technology
South Africa is unique in many ways â&#x20AC;&#x201C; we have urban and industrial areas that match numerous places in the Western world, but some of our industry is situated in outlying locations where skills and resources are limited. These challenges demand that when selecting a technology, we give attention to options that are both appropriate and sustainable. Technologies that are applied in our urban environments should be different to those in more remote areas. Issues such as robust design, skills requirements, availability of spares, overall plant ownership and management, legislation and capital and operating costs all need to be taken into account when selecting technology. Where possible, water re-use also warrants consideration. The final scheme that is developed must match the operator skills that will be available. Since the majority of effluent plants are simply a necessary expense and do not contribute in any way to the overall profitability of the business, they generally receive very little attention from maintenance and operating personnel. It is therefore important that the design ensures they are robust and only require the sUSTAINABLE Water Resource HANDBOOK
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minimal operator intervention. If the correct operator skills are not available for a particular technology, it will be doomed to failure, no matter how effective it might be. As a rule, always endeavour to make the design as simple as possible; should advanced technology really be necessary, ensure that operators receive the correct training. Where it can be afforded, having a professional third party organisation operate the wastewater plant is recommended – most companies prefer their personnel to focus on the core operation of e.g. making potato chips or beer; it is seldom that a company’s own employees will be able to dedicate the necessary attention to an effluent plant, the same way as a professional operating firm will. Specifically on the topic of sustainability, during the design, always look out for opportunities to make the wastewater plant justifiable in its own right, not only through reduction of local authority charges & fines, but also through the recovery of useful by-products, energy and water.
The design process
The design of a suitable industrial effluent treatment process must follow a methodical procedure to ensure a successful and robust solution. The exercise should start with a thorough characterisation of the effluent, in terms of flow, pollutant types and levels. A representative sampling and testing regime is important to obtain a true picture of the situation. Once the waste streams have been characterised, the next step is to decide upon the most appropriate route and technology for effluent management. Three aspects need be considered: • Type of pollutants – are they suspended, dissolved, biodegradable or toxic? • Final effluent quality – where is the effluent being discharged? Must it meet the General or Special Limits or is it for re-use? • Cost – before a final process selection, a budget costing should be performed since there are often several routes to achieve the same result; only one is the most cost-effective. After allowing for all waste minimisation and in-plant control opportunities (see 3.1 and 3.2 above), give consideration to each of the primary, secondary and tertiary treatment options, as well as the interaction between each. Draw up a Process Flow Diagram (PFD), complete with a full mass and energy balance and ratings for each unit operation. More than one final process scheme may appear to be feasible, but use further bench scale tests, piloting, costing and above all, simplicity, to make a final selection. During selection of the process scheme, designers should engage potential equipment and package vendors at an early stage – their experience in similar applications is invaluable and treatment techniques for industrial wastewater often require specialist know-how and track record.
Conclusion
Every industry has unique features and therefore a unique effluent. A successful treatment scheme starts with a thorough fingerprint of the process and a full characterisation of the wastewater. Always consider waste minimisation before developing an end-of-pipe treatment. Research the best practices for dealing with the various contaminants and perform adequate testing and piloting prior to going to full scale. Make sure operations staff are properly trained in both the running and the monitoring of the treatment plant. A properly designed and well-run industrial effluent treatment facility is an asset to that business as well as the environment.
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AFRICAN ENGINEERS OF SIGNIFICANCE Based on the skill and experience of its directors and Staff, ILISO Consulting is able to offer its clients a variety of services in disciplines of Municipal Infrastructure, Major Roads and Highways, Traffic and Transportation, Water Sanitation, Structures, Project Management, Geographic Information System and Environmental Management. The Environmental Management Discipline Group of ILISO was established in August 2005 and is fully aquainted with the relevant legislation and process required by government to adhere to it. Specialist skills and supportive services within ILISO and associated companies enable the group to successfully undertake and complete environmental management assignments, including integrated Environmental Management (IEM), Environmental Impact Assessments (EISs), Environmental Management Plans (EMPs), and Environmental Monitoring. The group has specialist capabilities in the registration and licencing of water users, assessing water requirements for basic human needs and riverine ecology, determining stream-flow assimilative capacilty for pollution loads, water quality guidelines and management plans, industrial wastewater treatment and disposal. Other competencies include Social Impact Assessments (SIAs), and public participation and consultation.
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environmental 12nov2009.indd 1
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Co m pa n y O v e r v i e w
Water and Sanitation Services South Africa (Pty) Ltd (“WSSA”) WSSA is a South African company which, for more than twenty years, has specialised in the field of management, operation, maintenance and administration of water and wastewater systems, in Southern Africa, within the Municipal, Industrial and Mining sectors. WSSA employs over 1800 people and operates throughout South Africa and Southern WSSA employs over 1800 people and is active on over 350 sites in 8 provinces in South Africa as well as in Southern Africa (Botswana, Namibia, Mozambique and Zambia). WSSA is privileged to be one of the 25 Water Institute of South Africa WISA patron members and has obtained from the Construction Industry Independent Board (CIDB) the 6 ME (mechanical engineering) and 7 CE (civil engineering) ratings.
WSSA: Our vision, mission & values Our Vision To be the provider of sustainable water and sanitation services in Southern Africa Our Mission WSSA provides quality and sustainable water and sanitation services through customer orientated partnerships with our municipal and industrial clients, by applying best practices, developing our people and protecting the environment. Our Values Professionalism Team spirit Ethics Respect for the Environment Sustainable development. PROVIDING SUSTAINABLE WATER SERVICES SOLUTIONS TO SOUTH AFRICA’S COMMUNITIES WSSA’s ISO and OHSAS certifications provide peace of mind to their clients
Co m pa n y O v e r v i e w WSSA masters the whole water cycle chain and offers the full range of service solutions tailored to meet the specific requirements of the client and the project. Through flexible contractual arrangements and innovative solutions, we can provide our municipal and industrial clients with any, or all, of the services in the value chain. We also provide ESETA accredited training and fast and accurate laboratory services.
Resources, technology, know-how and skills Design
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Systems CAPEX OPEX Personnel Assests Conformance Health & Safety Communication Skills Transfer
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Block E, Lincolnwood Office Park Woodlands Drive WOODMEAD P.O. Box 320, Rivonia, 2128
Tel: (0027 11) 209-9201 Fax: (0027 11) 804 5847 xxx@wssa.co.za www.wssa.co.za
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chapter 19: Mining Use of Water
Mining Use of Water Carin Bosman Director, Carin Bosman Sustainable Solutions
South Africa is a mining economy with some of the richest and deepest mines in the world and represents a critical resource for a wide range of minerals to drive the world economy. South Africa has a long history of mining and has limited natural water resources, leading to a situation where it also has to face a number of significant challenges related to the impact of mining on both the quantity and quality of water resources. According to the National Water Resources Strategy (NWRS), published by the Department of Water Affairs (DWA) in 2004, the South African mining and industrial sector consumed 755 million m3 per annum for the year 2000, or 6% of the total volume of water used in the country. Although mining has an enormous potential for re-use of water, with a potential available yield of almost 260 million m3 per annum of usable returns (NWRS, 2004), very few mining companies have implemented water conservation and demand management measures to optimise their consumptive use of water. With over 10 000 km² of hydraulically interlinked coal mines and over 300km of interlinked gold mines, mine water challenges extends beyond the boundaries of a single mine, and often presents a large scale problem that can have regional implications. Mining is a relatively uncomplicated activity: valuable minerals or other geological materials (usually non-renewable resources located in the earthâ&#x20AC;&#x2122;s crust in an ore body, vein or seam such as precious metals (gold, platinum, palladium), base metals, iron, chromium, copper, uranium, diamonds, limestone, coal, oil shale, rock salt, potash, etc), are extracted and brought to the surface through different types of opencast or underground mining methods. Following extraction, the ore is washed and sometimes refined in metallurgical processes. The complications with mining activities arise primarily due to the exposure of excavated minerals to the atmosphere and especially to water, either water encountered underground, or water entering the excavation as a result of run-off, and the waste products resulting from the beneficiation processes. When water comes into contact with the exposed minerals, particularly those containing pyrite , an iron-sulphate mineral, in the presence of oxygen in the atmosphere, sulphuric acid is formed, which lowers the pH of the water. This acidified water is known as acid rock drainage (ARD) or acid mine drainage (AMD). AMD can occur at any type of mine, from granite to coal mines. The retention time of the contact of water with the pyretic material enhances the formation of the acid mine drainage. Resulting from the formation of sulphuric acid, acidic conditions are created which cause heavy metals to become soluble and acid mine drainage eventually results in the heavy-metal contamination of ground- and surfacewater resources. These acids and heavy metals have toxic and even radio-active and other detrimental effects on humans and the environment. Most large mines, both opencast and deep mines in dolomitic areas, have to pump out large quantities of water found underground to be able to reach the minerals. If the water can be pumped out before it comes into contact with the pyrites that have been exposed in the underground rock during the mining process, the quality thereof will be acceptable, and it can be re-used on the mine or discharged into surface water bodies. However, this is not always the case, and release of contaminated water into the environment without appropriate management would have an adverse impact on the quality of the water in rivers as well as on groundwater in the vicinity of the mines. Especially for marginal mines, or mines that are no longer in operation, the risk of the mine voids filling with water and decanting acid mine drainage in an uncontrolled manner into the environment is a very real concern. This occurs currently at coal mines in the Witbank, Ermelo and Newcastle areas, as well as at gold mines on the East Rand, the West Rand (upstream of the Cradle of Humankind) and the sUSTAINABLE Water Resource HANDBOOK
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once the mines in the Far West Rand areas cease their mining activities, this could threaten the entire Vaal River system downstream of these mines. In combination with sulphate, the chlorides, nitrates, cyanides, and other salts used in the process of beneficiation, can lead to salination of water resources. Salination (or salinisation) refers to the salt content of water, and presents a huge challenge as it not only has an effect on the biota living in surface water bodies, but also since the removal of salts from both surface- and groundwater to render it fit for human use, has an enormous cost implication. Where the Total Dissolved Salts (TDS) concentration in typical dolomitic water would be in the order of 200 â&#x20AC;&#x201C; 300 mg/l, the TDS of water removed from the underground in a typical mining area is often exceeding levels of 1000 mg/l. Beneficiation plants generate large amounts of waste, called tailings or slimes. For example, 99 tonnes of waste are generated per tonne of copper, with even higher ratios in gold mining. Tailings, which are usually produced as slurry, are most commonly dumped into tailings dams or slimes dams, and due to the corrosive nature of the environment in which the metals is extracted, leachate and seepage from tailings dams contain both the salts and heavy metals described above, and threathen ground- and surfacewater resources alike. The activity of blasting, using ammonium-nitrate based explosives, and the large scale disturbance of soil leads to the release of nitrates, which, when dissolved in water, can have serious health effects, especially on children, and also contributes to the eutrophication of water resources. Eutrophication refers to the enrichment of water with nutrients, such as nitrates and phosphates, which gives rise to excessive growth of macrophytes and microscopic plants, for example, algae and cyanobacteria in rivers and reservoirs, and which causes the depletion of oxygen in the water, which in turn can lead to fish kills. Most cyanobacteria (often referred to as blue-green algae) are toxic, and may cause the water to be unfit for recreational, irrigation and domestic use since it can cause health problems. In addition, stormwater run-off from mining areas and tailings dams is a serious concern, as this run-off will contain the contaminants from the mine or disposed on the tailings dam, causing not only sedimentation of downstream water bodies, but also carrying with it the salts and dissolved heavy metals, including radio-active substances, which are deposited on the land where the run-off seeps away, affecting the soil quality and groundwater quality. Should this run-off reach surface water bodies, it will not only acidify the surface water, the heavy metals will also settle out on the sediment in the river bed, and will dissolve again under certain circumstances, such as heavy rain events. This creates a long term problem which is extremely difficult and costly to remediate and is the cause of the problems experienced in the Wonderfontein Spruit Catchment, where increased reports of birth deformations have been received, which are probably caused by elevated levels of radio-active materials deposited over time in the river bed as a result of mining activities, and which is currently the subject of research by both CANSA and the CSIR. Global indicators used to indicate the effects of mining on the quality of surface and groundwater are therefore mainly sulphates, chlorides, nitrates and cyanide, which, depending on the geology, the pH and the mining product, could be combined with increased levels of certain heavy metals. These contaminants, unless managed in a sustainable manner, will have serious detrimental effects on humans and the environment, especially on water resources, both during the mining operations and for decades after the mine is closed. This has led to most of the worldâ&#x20AC;&#x2122;s nations adopting regulations to moderate the negative effects of mining operations. In South Africa, the National Water Act (NWA) defines water use, and requires the authorisation of water use that is beneficial and in the public interest. Water uses that are associated with mining include the taking of water from ground or surface water resources, the storing of water, impeding or altering riverbanks or beds through river diversions, the discharge of minewater, the disposal of tailings and waste water, and the dewatering of water found underground. If an applicant for a water use licence can demonstrate that the impacts resulting from these activities will not have any detrimental effects on other water users, such water use will be licensed. It is usually a requirement that a mine submits an integrated water and waste management plan to indicate the management measures that will be implemented or maintained to ensure that potential detrimental impacts are appropriately managed and monitored. However, if any activity on a mine causes water pollution, such an activity will not be authorised, but will be dealt with in terms of section 19 of the Act, which requires those responsible to take all reasonable measures to prevent, control, and remedy the effects of pollution. Failure to do so is a criminal offence. In addition to these requirements, a set of regulations was promulgated in 1999 138
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under the NWA that is aimed at the protection of water resources and the prevention of pollution from mines. Their requirements aim to further prevent water pollution from mining activities by: • prohibiting the establishment of infrastructure within the 1:100 year flood-line; or within a horizontal distance of 100 metres from any watercourse or estuary, borehole or well • ensuring the confinement of unpolluted water to a clean water system, away from any dirty area, and the collection of water arising within any dirty area, including water seeping from mining operations, outcrops or any other activity, into a dirty water system • ensuring the operation of any dam or tailings dam that forms part of a dirty water system to have a minimum freeboard of 0.8 metres above full supply level • providing for the implementation of a compliance monitoring network To provide guidance to mining companies with regard to the measures to be taken to ensure that impacts resulting from their activities do not cause pollution, the DWA developed a series of Best Practice Guidelines, which include the following: • H1. Integrated Mine Water Management • H2. Pollution Prevention and Minimisation of Impacts • H3. Water Reuse and reclamation • H4. Water Treatment • G1. Storm Water Management • G2. Water and Salt Balances • G3. Water Monitoring Systems • G4. Impact Prediction • G5. Water management aspects for mine closure • A1. Small-Scale Mining • A2. Water Management for Mine Residue Deposits • A3. Water Management in Hydro-metallurgical Plants • A4. Pollution Control Dams • A5. Water Management for Surface Mines • A6. Water Management for Underground Mines The guidelines can be obtained electronically from the DWA’s website and can be used by the mining sector as input for compiling water use licence applications and otherl egally required documents such as Environmental Management Plans, Environmental Impact Assessments, Integrated Water and Waste Management Plans, closure plans, etc. These guidelines serve as a uniform basis for negotiations between government and the mining industry, and also as a guideline as to what the Department considers as best practice in resource protection and waste management, especially with regard to the treatment of mine water, cleaner production, water conservation and demand management, monitoring, etc. Responsible mining companies which correctly identify and manage the potential impacts from their mines in accordance with these guidelines can therefore continue to make a significant contribution to the country’s economy without causing detrimental effects on its fragile water resources. References National Water Act 36 of 1998 Regulation on Prevention of Pollution by Mining Activities: GN 704 in GG 20119 of 4 June 1999 National water Resource Strategy, DWAF, 2004 R. Adler, N. Funke, K. Findlater, and A. R. Turton, The Changing Relationship between the Government and the Mining Industry in South Africa: A Critical Assessment of the Far West Rand Dolomitic Water Association and the State Coordinating Technical Committee (Pretoria: Council for Scientific and Industrial Research (CSIR), 2006). A Akcil and S Koldas ‘Acid mine drainage (AMD): Causes, treatment and case studies’ (2006) 14 Journal of Cleaner Production 1139; C Bosman ‘Extending the duty of care – Harmony Gold Mines v Regional Director, Department of Water Affairs and Forestry (SCA) 2006’ Paper presented at the Environmental Law Association Workshop 3 November 2007. K Naicker, E Cukrowska & TS McCarthy ‘Acid mine drainage arising from gold mining activity in Johannesburg, South Africa and environs’ (2003) 122 Environmental Pollution 29. the sUSTAINABLE Water Resource HANDBOOK
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ESETA
The Eseta is a Sector Education and Training Authority for all the stakeholders in the water and energy sectors. We facilitate world class skills development for these sectors through the disbursement and management of discretionary grants, bursaries etc, in line with the scarce and critical skills relevant to our sectors. The Eseta has developed and registered qualifications for the water sector and is in the process of registering learnerships against these qualifications. Whilst this process is underway, we have facilitated a positive change in this sector by funding the training in waste water process operations, water purification, water reticulation services, electrical engineering, sanitation programmes, power plant operations, measurement control and instrumentation and network control. This represents the identified training needs within the Water and Energy sector. We have also funded the training of unemployed water related qualification graduates for workplace experience, more especially in the Greater Tzaneen (70), Vhembe (147) and uKhahlamba (75 – across all water related programmes) District Municipalities. The Eseta will continue to fund the training and development in this sector. For the year under review we have managed to certify the following numbers for the Water Sector across the different learning programmes: • Water related qualifications (150) and network control (50) • ABET programmes [( Johannesburg Water (200) • Thabo Mbeki Development Trust for Disabled people (25) • Loyiso Project (376 – across different water related qualifications) Erwat (73) and Rand Water (251) • Silulumanzi (55) • Vaalharts Water (41) • DWEA – KZN (41) ]. These represent some of the programmes funded. • Electrical engineering (1500) • Power plant operator (200) • Measurement control and instruments (79)
profile
We have a number of accredited training providers accredited by the Eseta ETQA to provide water related qualifications to the learners and assist in tackling the scarcity of skills in this sector, because without the proper skills, we will never achieve the set millennium goals. We also have the Eseta registered assessors and moderators for this sector who assist in ensuring that the learner achievements are appropriately evaluated. We are looking forward to increase the pool of all the above and ensure that all the training interventions carried out have a meaningful and measured impact, more especially in the rural areas, in changing lives for the better. We are also convinced that the Eseta is correctly positioned to deal with the sector issues in the upcoming landscape without failure. We have the support of the Accounting Authority in this regard. Together we are making a positive change. Essential contact details: Tel: 011 689 5300 Web: www.eseta.org.za E-mail: info@eseta.org.za Fax: 011 689 5340
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Water and Oude Molen – a case study in “the illusion of abundance” Mokena Makeka Principal MDL Architects
INTRODUCTION
Water covers over 70.8% of the earth’s surface. Ours is the only known planet in which water normatively exists in liquid form. It is one of nature’s most versatile and powerful compounds. Only 3% of the world’s water is fresh. Divided roughly, 2.4% is trapped in glaciers and other ice forms, and the remainder, – less than .06% – is in the form of rivers, ponds and lakes. Water quality has eroded significantly at the global scale; with severe impacts on biodiversity, water security, soil erosion, and in turn, food security. This precarious existence of mankind has managed to thrive on barely 1% of the world’s water and by and large it has been a practice of inefficiency, inequity and an illusion of abundance that threatens the viability of many cities the world over. This is exacerbated by a host of practices that use high quality, potable water for a range of industrial and social activities whose ultimate purpose is disproportionately related to the effort required to purify and supply potable water. A sense of limits in this regard is one that is re-emergent and will require a broader behavioral shift to appreciate the extent to which water enables society as a whole to exist. “Water is symbolic of the changes we are going through as a species and as a planet. Water has a myriad of uses, meanings and values, from political to environmental, social to mythological, cultural to spiritual.” (Donald Barnett, Just add Water|2009) Wastewater management is a global health, environmental and energy-use challenge. Urban cesspools are now more the norm in sub-Saharan Africa than at any other time. Over 90% of wastewater is often left to meander untreated into open water bodies or leach into the soil. The human cost is real: 25% of infant mortality (children below 5 years) can be traced back to untreated sewage. Dirty rivers, poor groundwater quality, unsightly urban centers, and shocking levels of public health, especially among the poor, are the principal byproducts of this neglect. The United Nations (UN) estimates that 2.7 billion people will face water scarcity by 2025 and in South Africa, demand is estimated to match supply within the next 5 years. Southern Africa is classified as a water scarce region. The topography of the meso-landscape and topsoil quality speaks to dominant savannah features with coastal forests and smatterings of riparian vegetation, with characteristics of temperate patterns, particularly in the Western Cape. The South African ecosystem is characterised by low rainfall, water scarcity and soils susceptible to erosion. Approximately 65% of the country receives less than 500 millimeters (mm) of annual precipitation, a threshold that is widely regarded by experts as the minimum required for rain-fed cropping. About 60% of South African cropland is characterised by low organic matter content. Low rainfall and fragile soils limit agriculture potential. Only 16% (about 16 million hectares) of the total amount of land used for crops and pasture is considered suitable for crops, while the rest is used for pasture. About 4% is high-potential agricultural land. It is estimated that South Africa has lost 25% of its topsoil since 1900 and that 55% of South Africa is threatened by desertification, but South Africa’s food needs are expected to double by 2020. This places not only a great pressure to re-conceive the role of water and water management at all applicable scales. Climate change over the past 30 years has exacerbated the periodic droughts experienced by the region. This coupled with an unchecked industrial environmental controls on water impact until recently, has created the conditions in which access to water becomes not only an environmental concern, but a social and political risk too. the sUSTAINABLE Water Resource HANDBOOK
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The case study as presented is part of a broader discussion; it is a tangible and ongoing opportunity and challenge toward transforming our understanding and management of water resources in the Western Cape. A critical aspect of understanding these challenges is to equally recognise the role of process and institutional engagement as a necessary enabler for detailed technical resolution to be implemented. There is no clearer example of such a challenge than Oude Molen. Oude Molen is a strategic provincial land asset, located on the edge of the Black River, in Cape Town. The strategic value of the site relates to a number of unique factors; it’s proximity to the Central Business District of Cape Town, adjoining working and middle class residential areas, extents of unique natural landscape in terms of immediate access to ravine environments, special status in terms of oral history and local regional memory and the presence of an intentional sustainable community. The precedent to be set by the scheme at various scales, ranging from financial to social sustainability, will set the tone for efficient, equitable and responsible use of state assets, while working towards achieving the constitutional imperatives as expressed in the National Bill of Rights. As such this exercise is more than a mere development, but a succinct and balanced attempt using trans-disciplinary practices to marry the full promise of the magnanimous and forward thinking legislation, towards real and physical implementation on the ground, and to make tangible the full and positive effects of sustainable development. The site is of further interest as it has the potential of assisting the subversion of the apartheid city model. Informal settlements that emerged first within the townships and then on public land throughout the major cities continue to grow, but receive few services, poor private sector investment and lack sustainable infrastructure. The inadequacy of the infrastructure, such as sewage systems, water supplies, and energy sources, means that the population relies extensively for its day-to-day needs on the local environment – including small vegetable plots and local streams, trees, and brush. Many of these communities are located in fragile environments close to hillsides, river valleys, poorly drained plains and in soil conditions which do not naturally support intensive agricultural land-use. A a result the environment quickly deteriorates. This city description and form obviously morphs into the specificities of locale; however, Cape Town is not an exception, but rather is an exemplar to the above. As such, Oude Molen has a literal and existential potential to address a range of conditions related to social integration, resource use and a re-imagination of urban development. The project currently resides in the rights acquisition phase – a process to rezone the site alongside the principles of a sustainable human settlement as an overriding imperative and demonstration tool for the public and private cooperation on state assets. As such the project is not in a detailed implementation phase, but rather sets out the, “in principle”, conditions upon which development can and should take place. This status in no way lessens the import of this interim condition, but sets out performance parameters that expose the soft underbelly and inefficiencies of current bureaucratic practices that are not in alignment with the bold and visionary policy statements which supposedly steer inter-governmental sphere cooperation and action.
Figure 20.1: Oude Moulen site
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The site is subject to a range of concerns and influences, but for the purposes of this studydiscussion, the Water Demand Management Strategy (2005) and Sewerage Treatment Investment Plan makes it clear that water efficiency will have to be built into all future development plans and that recycling will become a necessity. Under this rubric, the following must be taken into account: the necessity to develop viable urban agriculture practices on the buffer zone which makes contact with city land in the form on the river; Integrated water catchment management principles that will inform appropriate usage and development below the 1 in 50-year flood line; and lastly, the Black River and Liesbeeck River have been eroded of their biodiversity status through excessive contaminants upstream by various unchecked light industrial activities. A summary of the project’s contextual issues are described as follows: Mixed land-use To include a mix of land uses – commercial (retail, office, light industrial); residential (mixed income, mixed rental and ownership options); urban agriculture (food gardens/organics/permaculture); public spaces (sports/recreational/leisure); institutional (culture and heritage, education and training, healing and soulfulness) Housing density levels Densities could range from ± 400 to 600 residential units with various massing/scaling options. Housing would need to be affordable. OMV could be an incubator for young people to enter the housing market. Design and built environment The incorporation of eco-design principles (orientation, passive heating and cooling, ventilation, overhangs etc.) as well as the use of sustainable building materials that have a lower negative impact on the environment and human health. Appropriate sustainable technologies Design for efficient energy and water usage, solid waste disposal and sewage treatment and the inclusion of appropriate technologies in the planning and design for a future Oude Molen. Environmental: biodiversity and eco-system preservation Redevelopment must take cognisance of the very sensitive surrounding environment and its threatened ecosystems. Local economic development The mixed land use and mixed income residency to provide the opportunity and stimulus for local economic development. Cultural and heritage Retaining existing buildings of historical and cultural significance, including responding to oral traditions related to the significance of the Two Rivers Urban Precinct as a site of socio-cultural resonance for Indigenous Khoisan and Xhosa cultures. Ownership and governance Increasing consensus that the most appropriate ownership model for the future of the site should be that of a Public-Private-Community Partnership – allowing for a mix of rental (99-year leasing, Government rental stock, commercial rentals) and ownership options (Government subsidised, private, partial ownership). Demonstration site There is a strong sense that Oude Molen should serve as an international demonstration site for sustainable urban design and technologies. The urban design vision developed seeks to address a balance between competing concerns while maintaining the integrity of the public realm as a safe and convivial environment in line with the best attributes of pedestrian-friendly and dynamic place-making. A fine balance was struck between densification of the area and seeing itself as part of the wider TRUP (Two Rivers Urban Park) area. The the sUSTAINABLE Water Resource HANDBOOK
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open, green spaces in this scenario have been designed in a way that it complements and connects to the whole of the TRUP. Not only will the historic Manor House be restored as a cultural hub or centre, but space surrounding the Manor House has been made available to be shared by indigenous groups such as the Khoisan and amaXhosa. There are a number of technical conditions to be taken into account in terms of efficient and renewable resource usage: the Oude Molen project should not “connect up”, to the grid waste treatment system. The Athlone sewerage works are running at full capacity and to connect to the grid system would cost in the region of R70m. In this scenario this does not constitute an insurmountable problem. A combination of on-site waste treatment systems and technologies, such as a biodigester, biolytix and vertically constructed wetland, have been included to answer the challenge of “zero waste”. Equally, with the predicted increase in both demand for and costs of water and energy resources and services in future, the Oude Molen project cannot assume a ‘business-as-usual’ scenario. In this scenario all possibilities of rainwater harvesting and saving as well as solar and wind energy generation have been factored into planning for a future of reducing Oude Molen’s dependency on the water and electricity grid systems to an absolute minimum. Unlocking this potential is dependent on recognising the following: The National Water Resource Strategy has been unable to have a matching implementation effect at the municipal scale. Attitudes of policy makers, planners, and investors are notoriously rooted in the logic of “no return, no investment”. Environmental sanitation is considered an investment dead-end, an environmental rather an economic viability issue. Significant energy is required to deliver water and to process waste. So the corollary applies – change can bring significant energy savings. There are real opportunity costs in ignoring the energy and other resources in the waste, resources that current techniques and designs render less accessible through wholesale collection from highly differentiated sources and massive dilution. Investing in wastewater treatment must be seen as economically and financially advantageous, much like urban water supply. Attitudes, technologies, and costs are a dominant part of the complex set of causes of this problematic situation. Influencing and persuasion of these constituencies has to be ramped up aggressively. There is enough innovation, experimentation, good science and technology and concrete examples to implement sustainable neighborhood practices with some fundamentally different foundation concepts: • Modular installations instead of (ie or as adjuncts to) city wide trunk and branch systems in notserved (and refurbishment) areas. • Cascading water use from white to gray. The products and technology exist for transforming effluent into reusable inputs for a range of needs. Waste must be seen as input into new and existing value chains. • Acceptance of a mosaic of methods and choices within a single administration or institutional framework; adoption of the idea of “getting started” with an initial module, and incremental implementation (as opposed to waiting until finance is available for the conventional full scope model). • Collection and piping systems that allow “like sewage/wastewater” to be collected and treated (which could opens doors to ecosystem, small scale and biological methods), among other new high tech, even energy harvesting methods. • Treatment which corresponds to the next use of the water, whether aquifer or river recharge, agricultural or industrial use. “Just clean enough”, “Cascading uses for water” and “Fit for next use” are concepts that could revolutionise this field. Nutrients can be saved, health better protected and costs cut deeply. A Technology Inventory that presents a matrix of scalable choices for developers that will focus on least life cycle cost (in terms of money, energy, and water) – the decision to clean sufficiently, not more. 146
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• T echnologies that create “cascading use” – clean water for drinking and personal use, cascading down to grey water which can be “cleaned enough” for agricultural, urban, and industrial use which can be “cleaned enough” for recycling or environmental recharge etc. Sewage, either harvested for energy and/or nutrients then ‘cleaned enough’ for agricultural or environmental use. • Filters, energy sparing devices, re-use devices, reed bed examples, etc. Urban agriculture with monitored and controlled impacts on soil alkalinity, leaching, etc due to organic fertilisers. • The exploration of artificial aquifers and underground sequestration of water to reduce evapotranspiration as a matter of course for all developments above 7 hectares in size. • “As small as possible – as big as necessary”: The collection of existing prototypes and development of new designs for small cities and urban units. A mosaic of modules in the cities, not uniform design types. • A concerted effort to ensure that minimal impacts on the already degraded riparian system surrounding Oude Molen is undertaken, with an effort to remove alien vegetation, which distorts the water table and hydrological cycle. In support of this, the response to the Black River also involves soft interventions such as a river wide awareness campaign to inform human behavior within the immediate catchment area and especially within 300m of the 100 year floodline. This is in recognition that technological solutions do not necessarily lead to transformed habits and often unwittingly enables unsustainable behavior at the human and organisational scale. • Exchange ideas and experience concerning the involvement and education of civil society in water scarcity understanding and evaluation, in the planning of solutions and the evaluation of their consequences, in the learning of groundwater realities, specificities and significance, with an emphasis on elementary and high school students and their teachers, and existent civil groupings such as neighborhood watches etc. • The dissemination of successful uses of the component models which will use filters and “clean enough for next use” technology for a finite number of households/entities. As far as infrastructure is concerned, a Comprehensive Infrastructure Plan (CIP) will be required that will address the on-site requirements for roads and stormwater, water supply, sanitation, solid waste management, energy and telecommunications. It is again noted that previous reports have identified the fact that the bulk sewer from Maitland along the Black River is full, and is a serious constraint for new business as usual development. However, this is regarded as a positive factor because it reinforces the need for an on-site solution that has zero impact on underground water supplies, the wetland and the river.
The following approach is recommended for detailed development
• E nergy: A state-of-the-art comprehensive energy and electrical infrastructure plan that demonstrates that it is possible for a medium-sized urban development to use 60% less grid energy than developments of a similar size and nature and that this will be achieved in ways that will cost the state/taxpayer and users less than a conventional 100% grid-supply solution. Most of these gains will be achieved via architectural designs of commercial, residential and renovated buildings that take into account energy efficiency. This will be complemented by combining grid–supplied electricity with solar power (in particular solar water heaters), LP gas (in particular for cooking and possibly heating), wind power, biofuels (e.g. biodiesel, bio-ethanol) and biogas. A portion of the existing Ward 20 facility could be used to house the plant and equipment that will be required to achieve this. • Sanitation: On-site treatment and re-use of all sewerage via the combination of 3 technologies, namely Biogas Digestors, Biolytix Filters, and insulated Vertically Integrated Wetlands. Treated effluent, that will be of a much higher quality than the quality of the water in the Black River, will be used for flushing toilets and irrigation in selected areas. The main aim is to eliminate the need the sUSTAINABLE Water Resource HANDBOOK
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The Sustainable Series:
Handbooks for Environmental Stakeholders More than fifty thousand people in South Africa will read at least one of the Handbooks in the ‘Sustainability Series’ this year. The 5 Handbooks in the series are published by alive2green in a high quality A5 format and are available for purchase online at www.alive2green.com/handbooks. The Sustainability Series Handbooks tackle the key areas within the broader context of sustainability and include contributions from South Africa’s best academics and researchers. The Handbooks are designed for government and business decision makers and are produced in Volume format. Each new Volume builds on the previous Volume without replacing it. The Sustainable Transport and Mobility Handbook and the Green Building Handbook deal with two sectors that are the largest contributors to greenhouse gasses. The Water and Energy Handbooks tackle the issues and solutions that South African’s face with two of our most important resources and finally the Waste Handbook deals with the principles concerned with waste minimisation and ultimately waste eradication. The Handbooks also profile some of the top companies and organisations that are represented in each important sector.
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chapter 20: Water and Oude Molen – a case study in the illusion of abundance
to remove sewerage from the site entirely. This will prove that the high costs of bulk sanitation infrastructure can be substantially reduced, thus benefiting both the users and the state/taxpayer. The existing Ward 20 facility is ideally suited to house this facility because it is located at the lowest point on the site. The biogas generated by the Biogas Digesters can be used to generate electricity (that could, in turn, drive the pumps required to pump grey water back to the houses) or it can be piped into a community kitchen and used for cooking. • Water Supply: Water requirements will be met by combining municipal bulk water supply which is currently rated as adequate with on-site rainwater harvesting, and the use of grey water (recycled sewerage) for toilet flushing and irrigation. This will reduce the consumption of water by 40% compared to similar urban development’s of a similar size. The current Ward 20 facility is ideally suited for housing a rainwater/stormwater storage or recycling/energy/production facility. • Solid waste management: All solid waste will be collected and recycled on site in an appropriate compartment of the Ward 20 facility. All separated waste will be solid to recyclers. Organic waste will be deposited in the biogas digester or the Biolytix Filter, and fresh organic waste and green cuttings will be composted. The fact that no solid waste will need to be removed to landfill from the site will demonstrate that the costs usually carried by the Municipality/tax base for transporting solid waste, by nature which provides the landfill site, and by poor communities who usually live adjacent to landfill sites, can all be removed. • Stormwater: Given the wetland and river below the site, untreated stormwater runoff should be eliminated as far as practically possible. This is achievable for most of the year, but may be too costly to achieve for about 3 of the high rainfall winter months.
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Only tried and tested technologies were to be used to implement the infrastructure systems referred to above. All the technologies referred to are commonly used in cities around the world. For example, the City of Stockholm deposits all sewerage and organic waste into Biogas Digesters which, in turn, generate biogas that are used to power Stockholm’s bus fleet and municipal vehicle fleet. The Biolytix Filter system has been operating at Spier Wine Estate and Lynedoch Ecovillage for over four years without a major problem. Holland has perfected the dual water supply system in many developments where they channel grey water into houses to flush the toilets. Solar water heaters are proven even in the South African context, and LP gas stoves are already extensively used in South Africa. On-site solid waste recycling is a low-tech process that creates jobs. Cape Town has the largest number of recyclers in the country and therefore sale of separated waste will not be a problem. These are the parameters which have informed the development principles and can in turn lead to not only a revolution of water management at the neighborhood scale, but offer clear demonstrable and replicable knowledge for a re-imagination and respect for water at the human level. South Africa has a globally recognised model for water conservation and management through the noteworthy efforts of Professor Kader Asmal (recipient of the Stockholm Water Prize in 2000 for his “unprecedented efforts in the field of water management”) at the meso and macro scale. Water scarcity is due in part to inadequate institutional and socio-organisational action. Resource consumption at the metro scale, water scarcity and an ailing uneven economy have put a strain on the ability of the province and the city to truly leverage equity into bulk service improvements in general, and by extension defining which particular solutions are most appropriate will depend on further intensive work in the implementation phase. Oude Molen represents a singular and unique chance to engage, inform and influence civil society in the attainment of water responsible development and nation building.
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profile
Anglo American SA Anglo American is a global leader in mining, focused on adding value for shareholders, customers, employees and the communities in which it operates Anglo American produces some 2% to 2.25% of South Africaâ&#x20AC;&#x2122;s GDP and is the largest private sector investor in the country. We are also the largest private sector employer in South Africa, with approximately 77,000 permanent staff and around 35,000 contractors. Reducing our ecological footprint The award-winning eMalahleni water reclamation plant, a public-private initiative jointly initiated by Anglo Coal South Africa, BHP Billiton Energy Coal South Africa (BECSA) and the eMalahleni Local Municipality, was originally intended to provide a solution to the operational, safety and environmental challenges associated with rising underground mine water. Today it represents a worldclass sustainable development project with far-reaching benefits for its surrounding communities. Of the 25 megalitres of water it purifies to potable quality every day, 18 megalitres are supplied to the eMalahleni local municipality, which has struggled to meet the water demands of the fast-growing Witbank area. All the water needs of Anglo Coalâ&#x20AC;&#x2122;s Greenside, Landau and Kleinkopje collieries, as well as its shared services departments, are met by the plant. The eMalahleni plant has embarked on its second phase, which will increase its capacity to 33 megalitres of potable water daily. Investigations to implement similar projects in the Witbank-Middelburg coalfields in collaboration with the other major mining houses and the national power utility, Eskom, are in progress.
The eMalahleni water reclamation plant in the Mpumalanga province
Anglo American aims to reduce the ecological footprint of our business and unlock the sustainable development value inherent in the minerals we produce, for the greater benefit of society. An important aspect of this vision is to create synergies between poverty alleviation and a healthy environment. This entails linking innovative solutions to problems relating to degradation of the environment, biodiversity loss, poverty and being a catalyst for integrated forms of economic, social and environmental development. Contact Us Anglo American South Africa 44 Main Street Johannesburg 2001 Switchboard: +27 11 638 9111 Fax: +27 11 638 2557 www.angloamerican.co.za
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chapter 21: CASE STUDY: ATLANTIS WATER RESOURCE MANAGEMENT SCHEME
CASE STUDY: ATLANTIS WATER RESOURCE MANAGEMENT SCHEME Gideon Tredoux, Julia Cain, Ricky Murray
INTRODUCTION
The town of Atlantis is located 50km north of the centre of the City of Cape Town on the dry, west coast of South Africa. It has a population of 57 000 people and presently forms part of the metropolitan area of Cape Town. Initially prompted by the need to find an alternative to marine wastewater discharge, Atlantis began recharging its stormwater and treated wastewater into its sandy soils in 1979. With the recognition that the natural groundwater yield of the aquifer was not sufficient to meet the long-term needs of the town, the focus shifted to recharging the aquifer and recycling water. The addition of stormwater to the recharge system was a major development, as was the eventual separation of domestic and industrial effluent that was done in order to allow recharge of the highest quality water in the areas of the greatest importance. Currently, treated domestic effluent, all of the domestic stormwater, and most of the industrial stormwater is used for recharging the aquifer up-gradient of the wellfields in two infiltration basins. Industrial effluent and industrial stormwater from the noxious trade area is diverted to the coast down-gradient of the main aquifer to coastal recharge basins in order to raise the water table and prevent seawater intrusion into the main aquifer. The overall scheme is referred to as the Atlantis Water Resource Management Scheme (AWRMS). AWRMS has successfully recharged and recycled water for almost 3 decades. It is estimated that approximately 7500 m3/d of stormwater and wastewater is currently recharged up-gradient of the wellfield, thereby augmenting the water supply by more than 2.7x106 m3/a (i.e. approximately 25 - 30% of Atlantisâ&#x20AC;&#x2122; groundwater supply is augmented through artificial recharge). Some 4 000 m3/d higher salinity industrial wastewater is treated and discharged into the coastal basins down-gradient of the wellfield close to the ocean. The AWRMS provides a local South African example of a cost-effective artificial recharge solution that has been proven over time, successfully supplying water to both the residential and industrial areas of Atlantis for nearly 30 years. A renewal of careful management of the water sources and aquifer is now required to ensure its future long-term sustainability.
Figure 21.1: Overview of Witzand part of the AWRMS the sUSTAINABLE Water Resource HANDBOOK
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Figure 21.1.1 shows which Department in the City is responsible for the specific part of the AWRMS. A coordinating structure is required to ensure a seamless operation providing high quality water after recycling. Whereas stormwater detention basins 1 to 4, 8 and 11 were designed to be mostly dry and only serve for peak flow reduction, basins 5, 6, 9 and 10 were designed or redesigned to act as wet basins in which reed beds developed. The Donkergat River serves as an alternative discharge point for wastewater mainly during maintenance work on the system.
EARLY HISTORY OF THE TOWN
Atlantis was a planned town from its inception. Originally conceived as an apartheid concept, the town planners of the time were heavily influenced by the “New Town” ideas that had developed in post-war England. The New Town concept embraced the idea of building carefully planned towns, in areas far enough away from other centres to be self-contained, typically in previously underdeveloped areas. Part of this vision was that all those living in a New Town would have work within their town as well. In the South African context of the early 1970s, Atlantis was planned within the apartheid context as a “coloureds only” new town, making it a uniquely South African version of the New Town approach. This historical association with apartheid became detrimental to Atlantis’ post-apartheid future development, and to a certain degree negated the good planning that went into the town’s early development. The original planning concept that local government was tasked with implementing was for a city housing approximately 500 000 people in 6 interlinked towns. Ultimately, however, only one town, known as Wesfleur, came to fruition. Over time, this has simply become known as Atlantis. The idea driving the development was to help to ease the over-population of Elsies River, which was by that time a Grade 1 slum with a population of 110 000 living in an area built for 60 000. Some saw the development of Atlantis as an opportunity to start with a clean slate and build a high quality town. Thus in 1976, the Atlantis area was declared a National Growth Point under the government’s “decentralisation initiative.” Development began in Atlantis with a combined residential and industrial component. Effort had to be made to attract both industry and residents to this new town that was located relatively far away from Cape Town. Various incentives were introduced for attracting industries. Water supply and quality were a key issue for industry in terms of re-location considerations. The first residential construction in Atlantis began in the Avondale area where 635 houses were built in the first phase. The facilitation of home ownership ultimately contributed to significant wealth creation for the skilled and employed members of this new community. Skilled “coloured” people who moved to Atlantis got top jobs within the factories and industries based there. However, Atlantis never escaped the problems of unemployment, poverty, and over-crowding as had been hoped. Another issue for people living in Atlantis was the difficulty of changing jobs – unless a person could find alternative employment within Atlantis, changing jobs generally meant moving from Atlantis because it was so far away from Cape Town. Early hopes for developing a light rail system for Atlantis never came to fruition. “Two things hindered the further development of Atlantis: 1. The tax exemptions offered by government to industry were stopped; and 2. The transport link between Atlantis and Cape Town was a mess-up.” Rodney Bishop, interview, 2009. Rodney Bishop, the Principal Engineer at the Bulkwater Branch at the City of Cape Town, has played a key role in the management of the AWRMS since the scheme was transferred to the Cape Metro Council in July 1997. By 1987, there were approximately 50 industrialists in Atlantis, employing people drawn from some 8 000 housing units. However, by the end of the 1980s, the industrial incentives had stopped and Atlantis had come to be equated with apartheid. Furthermore, the government’s failure to attract 154
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business to the town undermined its potential growth and development and the grand plan for a self-sustaining city of 6 towns was abandoned. Despite this, Atlantis is still one of the largest towns in the Western Cape. Once the out-lying area of Table View fills up, further development may come to Atlantis.
WATER SUPPLY: EARLY OPTIONS AND DEVELOPMENTS
At the time of the construction of the first houses in Atlantis, the water supply was provided from one borehole. Later, a weir was constructed to capture the perennial spring flow at a small dam, from which it was pumped to a reservoir and then gravity-fed on to Atlantis. However, there was a general recognition that more water would soon be needed than could be abstracted from this small weir. A plan was put forward to use the surface water of the Berg River some 70 km distant as it was the closest feasible source of reliable surface water to the semiarid west coast location of Atlantis. However, the next step in augmenting water supply to Atlantis that actually took place was the development of the Silwerstroom well field around the spring. John Clark, the Chief Engineer of the Divisional Council of the Cape (DCC) during the 1980s, was interested in groundwater. From the early 1970s, the Department of Water Affairs and Forestry (DWAF) was doing a lot of groundwater exploration by drilling investigatory boreholdes, as part of this, groundwater was found in the Atlantis area. By 1978, the first production boreholes had been drilled at Silwerstroom. With the realisation that there was a lot of water in the aquifer, the Silwerstroom wellfield was developed. Soon thereafter, DWAF identified the possibility of a wellfield in the Witzand area. This proved to be a good groundwater area and later became the main wellfield for Atlantis. The Berg River plan never materialised. The cost would have placed a huge financial burden on the growth point. Thus the DCC was interested in developing interim measures in order to postpone this undertaking. Largely thanks to the innovative thinking of the engineers and scientists involved at the time, the “interim” groundwater supply was developed into a long-term solution for Atlantis and eventually came to incorporate artificial recharge. The two wellfields, have thus been providing a sustainable groundwater resource for close to 30 years. Only since 2000, was limited augmentation of the water supply by surface water introduced via an alternative route.
TOWN PLANNING, STORMWATER & WASTEWATER LAYOUT
Atlantis benefited from the planned separation of residential and industrial areas. All residential areas were developed in the northern half of Atlantis, while the industrial areas were developed in the southern half. Furthermore, the borders of the noxious trade area were delimited to its southwestern corner. The interaction between the town planners and the designers of the stormwater management scheme was significant during the development of Wesfleur. It was the first case in South Africa of integrating detention basins into the urban design of a town. The planning at the time incorporated the latest ideas regarding the construction of the stormwater collection and wastewater treatment systems. The different systems – water supply, wastewater, and stormwater – were all initially separate, but then became integrated through the development of the AWRMS. The development of the stormwater system began in the late 1970s and modifications had to be made to accommodate this system (e.g. slopes of roads; pipelines). This was to some extent influenced by workshops held in South Africa by the American Environmental Protection Agency (EPA) at that time, which seriously promoted the ideas of stormwater detention and artificial recharge. Initially in Atlantis, detention basins were developed simply to control peak flow, mirroring the latest international technology at the time, and its continued operation over the past 30 years has proven the system’s effectiveness to deal with urban runoff. The system later evolved into one of recycling stormwater by recharging it into the aquifer. From the wastewater side, the sewage of Atlantis’ original 2000 unit development was initially dealt with through one Wastewater Treatment Works. The first WWTW was a plastic lined oxidation pond. The activated sludge works with maturation ponds was started in October 1978. Basin 7 was both the final disposal pond as well as the main recharge basin. It continues to be directly fed from Basin 6, the sUSTAINABLE Water Resource HANDBOOK
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which is a collector and final polishing wet pond serving as an artificial reed bed. There were occasional oil spills in the industrial area and the reeds that were encouraged to develop in the stormwater retention ponds in these areas worked very well in dealing with these situations
Figure 21.2: Layout of AWRMS
THE ARTIFICIAL RECHARGE SCHEME â&#x20AC;&#x201C; Conceptualisation
The ideas for artificial recharge emerged over time within the circle of experts brought together under the leadership of John Clark. Marine discharge had been a common method of disposal in South African coastal areas up until that time because of convenience. However, this situation was changing due to public resistance in the 1970s, and because DWAF was not in favour of sea outfalls because it resulted in a loss of water. Clark was aware of the pilot scale artificial recharge studies using treated wastewater that the CSIR had been carrying out in the Cape Flats from 1973 to 1979 (Tredoux et al.,1980). This example provided an attractive alternative for dealing with wastewater. Hence the residential and industrial effluent (jointly treated at the time in the combined Wastewater Treatment Works) was directed from maturation ponds onwards to detention ponds for infiltration into the sandy soils of the area. By 1979, the case had also been made to add the urban stormwater runoff into the wastewater recharge system â&#x20AC;&#x201C; as a means of dealing with stormwater. (It also meant that the stormwater was not lost). Once the aquifer was studied more intensively, it emerged that the natural yield of the aquifer was insufficient to sustain the water supply to Atlantis in the longer term. The need for water recycling introduced a new perspective to the water management system at Atlantis and the management of water quality throughout the system became a key issue. The industrial wastewater was significantly affected by various industries, particularly the textile industries, that had set up their own water softening works, which meant a large quantity of sodium chloride was being added to the industrial effluent, which in turn significantly downgraded it. Out of this need to ensure water quality, various role-players began to push for the separation of domestic and industrial wastewater treatment, and the recycling via the aquifer of only the treated domestic wastewater. After completion of the new domestic treatment works, the old wastewater treatment works was refurbished for treating the industrial wastewater. The idea later emerged for the stormwater system which was later adjusted to channel peak flow and base flow to different recharge basins to maintain good quality water in selected areas of the aquifer. At the time the AWRMS was initiated more than 3 decades ago, the Water Act No 54 of 1956 was in force in South Africa. That Act did not have any sections dealing with the authorisation and regulation of artificial groundwater recharge nor with the recycling of water. The National Water Act (Act No 36 156
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of 1998) replaced the Water Act of 1956 and the new Act specifically controls artificial groundwater recharge through a permitting system. Artificial recharge has played a key role in the augmentation of the groundwater supplies at Atlantis. Whereas initially indirect recycling of wastewater and urban stormwater runoff was considered an economic means of wastewater disposal, water conservation became a key feature of the scheme. Various combinations of urban stormwater and treated wastewater from sources in the town have been infiltrated into the aquifer over the years to maximise the available groundwater. In this way the Atlantis Water Supply Scheme has pioneered the application of artificial groundwater recharge as a water management tool for bulk water supply in southern Africa.
The Atlantis Aquifer
Atlantis is located along the semiarid to arid west coast of South Africa (Figure 21.3), with most of the 450 mm mean annual rainfall received from April-September. Due to the sandy surface over most of the area, recharge percentages of 15-30% of the annual rainfall are generally experienced, with the higher recharge occurring in the un-vegetated dune area.
Figure 21.3 Location and layout of Atlantis water supply system
Design of the Atlantis Water Resources Management System
The various components of the Atlantis Water Resources Management System as it currently exists are shown schematically in Figure 21.4.
Figure 21.4 Components of the Atlantis Water Resource Management System the sUSTAINABLE Water Resource HANDBOOK
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The large volumes of stormwater runoff that were anticipated after urbanisation and the associated hardening of surfaces was seen as a valuable water source for augmenting water supplies and this prompted the construction of a stormwater collection system. The stormwater system now consists of 12 detention and retention basins and the necessary interconnecting pipelines with peak flow reduction features (Liebenberg and Stander, 1976). The stormwater system at Atlantis was designed with the flexibility to control water flows of differing salinity and to collect the best quality water for infiltration into the aquifer. The vegetation and natural characteristics of the aquifer material affect the groundwater quality, e.g. it imparts high hardness to the water, significant dissolved organic carbon and measurable dissolved iron or high salinity to the water. This level of “hardness” was not acceptable to industry, and as part of their incentive package, a Water Softening Plant was constructed in 1986 to improve the quality for industrial uses, particularly the textile industry. Initially all wastewater was treated in a single wastewater treatment plant and all the treated effluent was used for artificial recharge. In November 1986 this practice was discontinued due to water quality considerations and separate treatment plants were constructed for domestic and industrial wastewater treatment. These came online in 1992. At Basin 6, the domestic wastewater effluent is blended with the urban stormwater runoff before discharge into the main recharge Basins 7 and 12. The more saline treated industrial wastewater is discharged into the coastal recharge basins and seeps into the ocean through the subsurface.
Scheme construction
The AWRMS, which is based on the integration of its water supply, wastewater, and stormwater systems was developed over time. It took approximately 40 different projects to develop the entire integrated scheme as it now exists.
Operation
The water reclamation scheme at Atlantis is presently operated by the City of Cape Town, with the CSIR having been involved in an advisory capacity for more than 25 years. In principle, urban stormwater runoff and treated domestic wastewater are recycled via the aquifer and augment the limited natural yield of the Atlantis aquifer. An important feature incorporated into the Atlantis recharge system is the separation of the stormwater runoff and wastewater into components of different qualities, mainly with respect to salinity (Cavé and Tredoux, 2002). This allows the recharge of lower salinity water in parts of the aquifer where the natural groundwater salinity is lower. Hence two recharge basins were constructed with Basin 7 intended for higher salinity water and Basin 12 for lower salinity water. The more saline industrial wastewater and high salinity stormwater from Basin 10 are diverted to the coastal recharge basins and are not used for recycling water in the main part of the aquifer.
Changes in operation over time
The limitations of the groundwater supply and the fact that there was surplus water available in the Melkbosstrand area led to the linking of the Atlantis water supply to the main Cape Town water scheme via a link to the pipeline from Voëlvlei Dam in 1998, allowing the importation of low salinity surface water. A difficulty presently (2009) experienced in the operation of the scheme is the borehole clogging, which seriously affects the wellfield production capacity. One result is that larger volumes of surface water from the City of Cape Town are currently being imported. Hence the groundwater (and recycled water) content of the final water supply may be as low as 50% at this stage (2009). This means that the aquifer is not currently being optimally utilised. However, an important spin-off is the decrease in overall salinity in the system. This is brought about by the low salinity imported surface water which is recharged into the aquifer after use and which blends with or displaces more saline groundwater. This improves the quality of the water and is also useful as it helps avoid the problem of bio-fouling, which affects all production boreholes. 158
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Basin clogging
“Basin clogging” refers to the build up of fine sediments and organic material on the bottom of a basin over time. This build-up of material slows down the infiltration rate (i.e. the rate at which the water goes into the ground) of the recharge basin. In the case of Atlantis, the infiltration rate decreased noticeably over the years in Basin 7 (the original recharge basin). Initially, a heavy load of fine particles and sand reached Basin 7 where a large part thereof was deposited in the stilling basin at the inlet (which acted as a silt trap), but also in the basin itself. To address this situation, action was taken in two ways. Firstly, Basin 6 was modified in 1988 and changed from a dry to a wet basin. Soon thereafter reeds established themselves in Basin 6, and since then the sand and silt transported by the stormwater system is now deposited at the outlet into Basin 6 so that it acts as a silt reduction point, greatly reducing the amount of silt carried on to recharge Basin 7. Following these modifications, all flow was diverted temporarily, allowing Basin 7 to dry out completely in 1989. A front-end loader was brought in to scrape away the layer of sediment at the bottom of the basin. This improved the infiltration rate dramatically, also because the water level in the subsurface had dropped in the meantime. (In the 20 years since then, however, it has never been cleaned again).
Borehole clogging / Iron bacteria
The first well clogging occurred in the early 1990s when due to drought conditions the boreholes were over-pumped and air entered the screened section of the borehole. The situation was aggravated because the construction of the wastewater treatment plant was still in progress and only stormwater runoff could be recharged. The first regenerant used to address the borehole clogging was citric acid. This was a fairly successful treatment initially but was only effective for the short-term. In the latter half of the 1990s, borehole clogging emerged as a serious problem. Borehole rehabilitation restored yields for many of the 37 production boreholes treated, but the treatment methods seem to have certain limitations. The rehabilitation process needs further research and development, integrated with a detailed water quality and performance monitoring programme for the production boreholes. An investigation into the causes of clogging included a survey of the abstraction conditions, which revealed that the boreholes were often stressed by pumping above the recommended rate, and that some of the pumping infrastructure, such as flow metering equipment, needed mending or replacement.
Other problems
The following constitute threats to the sustainability of the Atlantis water supply: • Uncontrolled abstraction threats from small and medium scale users e.g. private boreholes of agricultural smallholdings and industries • Uncontrolled abstraction due to rife infestation of alien vegetation in the area • Financial and staffing constraints; • Threat of saline water encroachment and increased groundwater salinity • Groundwater pollution threats from the following: Caltex oil pipeline that runs through part of a wellfield; potential hazardous chemical spills in industrial area and potential hazardous spills by road or rail that could either enter aquifer directly or get into stormwater flow and arrive at aquifer through recharge basins • Point sources of pollution (although known sources have been sited away from productive areas of the aquifer that deliver high quality water e.g. cemetery; wastewater treatment works) • Non-point sources of pollution including informal settlements without services; agricultural practices by small-scale farmers; and industrial activities in industrial areas the sUSTAINABLE Water Resource HANDBOOK
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LESSONS LEARNED
Ultimately, the Atlantis Water Resource Management Scheme has proven itself as an innovative and highly successful scheme that has won various awards and worked extremely well. The AWRMS has proven that these types of recharge schemes are feasible: that they can be managed; that it is possible to integrate stormwater; and that it is possible to separate different types of wastewater and stormwater and manage them all. The performance of the water recycling system at Atlantis has shown itself to be relatively robust with respect to the elimination of contaminants, and based on present knowledge, the recycling of the water does not present a threat to the potable water supply. On a more cautionary note, an integrated scheme requires integrated management. Ensuring the longer-term sustainability of the AWRMS requires proper maintenance of all the components. The subsurface passage of the water plays a key role in the microbiological safeguarding of the system. The AWRMS is a complex operation and its successful operation requires a multidisciplinary approach. The integrated management controlled the water supply system, wastewater treatment, urban stormwater collection and disposal system, monitoring of all water quality (i.e. aquifer, wellfield, treated water, distribution system, wastewater, stormwater (various points), recharge basins, disposal systems, discharges by industries, etc.). Coordination between Bulk Water, Wastewater, Roads and Stormwater, Parks and Forests, and all other relevant structures is essential for the proper functioning of the water supply system. For the City of Cape Town, groundwater as a water supply source is a new venture, and “ownership” has to be embedded into all the administrative avenues. The Atlantis Water Resource Management Scheme provides a useful case study for those interested in developing future sustainable communities and better utilising available water resources. REFERENCES Colvin, C., Le Maitre, D. and Hughes, S. 2001. Assessing vegetation ecosystem dependence on groundwater. Draft report to the Water Research Commission. Liebenberg and Stander (1976). Planning and Masterplan for the Stormwater Network, Outfall and Disposal System. Report GW/EduT/1961 PC. Cape Town: Liebenberg and Stander Consulting Engineers. Rogers, J. (1980). First report on the Cenozoic sediments between Cape Town and Elandsbay. Open File Report 1980 – 0249. Pretoria: Geological Survey of South Africa. Tredoux G, Ross W R and Gerber A, (1980). The potential of the Cape Flats aquifer for the storage and abstraction of reclaimed effluent (South Africa). Z. dt. geol. Ges., 131, 23 – 43 Tredoux G (1987). The role of artificial recharge in groundwater management at Atlantis. Paper presented at the Biennial Conference and Exhibition. Organized by the Institute of Water Pollution Control (S A Branch), Port Elizabeth, 12 - 15 May 1987. Tredoux, G, King, P B, & Cavé, L C (1999). Managing urban wastewater for maximising water resource utilization, Wat. Sci. Technology, 39, 353 – 356. Tredoux, G and Cavé, L C, (2002). Atlantis Aquifer: A Status Report on 20 Years of Groundwater Management at Atlantis. Report submitted to the City of Cape Town. CSIR Report No ENV-S-C 2002 069. Van der Merwe, A.J. (1983). Exploration, development and evaluation of groundwater in the sand deposits in the Atlantis area for water supply to the Atlantis growth point. M.Sc thesis. Bloemfontein: University of the Free State. Wright, A (1991). The artificial recharge of urban stormwater runoff in the Atlantis coastal aquifer. M.Sc thesis. Rhodes University, Grahamstown, 117 p. (Unpublished). Wright, A. (1994). Artificial recharge of urban wastewater, the key component in the development of an industrial town on the arid west coast of South Africa. In: Water Down Under ‘94. Proceedings of the IAH Congress: Vol.2, Part A, 39 - 41. Adelaide: International Association of Hydrogeologists.
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profile
Hanna Instruments In 1988 Hanna Instruments opened in South Africa with the Head Office based in Bedfordview with branches in Cape Town and Durban and an area distributor is based in Port Elizabeth. Hanna Instruments (Pty) Ltd are the sole importers and distributors of Hanna Instruments, such as meters, electrodes, chemical reagents and buffer solutions for use in laboratories, food industry, water purification plants as well as in the agricultural industry, chemical and industrial markets, etc. Products supplied by Hanna Instruments for testing and analysis purposes include - pH, ORP (Redox), Conductivity, TDS, Dissolved Oxygen, Relative Humidity, Temperature, Turbidity Chemical Oxygen Demand, Magnetic Stirrers, Chemical Test Kits, Titrators, Refractometers, Ion Selective Electrodes, Dosing Pumps, pH & ORP Electrodes, Water Quality Instruments for: Ammonia, Alkalinity, Aluminum, Bromine, Hardness, Chloride, Chlorine Dioxide, Chlorine, Chromium VI, Copper, Cyanide, Cyanuric Acid, Fluoride, Hydrazine, Iodine, Iron, Manganese, Molybdenum, Nickel, Nitrate, Nitrite, Nitrogen, Ozone, Phosphate, hosphorous, Potassium, Silica, Silver, Sulphate & Zinc. Calibration & maintenance solutions. Hanna Instruments prides itself and believes in controlling the quality of our products from their inception to delivery, as well as our after sales service. Technical support is readily available. Our products are covered by a warranty.
HI 83224 - Chemical Oxygen Demand
HI 98703
HI 9828
All Hanna products are in compliance with CE directives and our production facilities are ISO 90001 certified. Contact Us Hanna Instruments (Pty) Ltd, 6 Vernon Road Morninghill, Bedfordview, 2197 P.O. Box 1646, Bruma, 2026 Tel: (011) 615 6076 Fax: (011) 615 8582 e-mail: hanna@hanna.co.za website: www.hanna.co.za
COD meter and Multiparameter Photometer
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ENVIRONMENTAL MANAGEMENT AND GEOGRAPHIC INFORMATION SYSTEMS TRAINING
EMGIS
VISION AND MISSION The EMGIS vision is to try addressing challenges facing the environment. Natural resourcesare being exposed to human activities leading to their detoriation. The mission of the EMGIS is to reduce the burden of human illness and dysfunction from environmental exposures by analysing natural resources such as water, soils, and plants; EMGIS achieves its mission through multidisciplinary research programs, prevention and intervention efforts: and EMGIS communicates strategies that encompass training, education, and community outreach. EMGIS ACTIVITIES EMGIS had assessed the condition of waterworks, boreholes and protected springs of OR Tambo District Municipality and also audited the skills of the waterworks operators. EMGIS has manufactured and supplied bleach (Sodium Hypo.) for water treatment in the rural areas of King Sabata Dalidyebo (KSD). Also conducting awareness campaigns on water quality and waterborne diseases in the rural areas of KSD. EMGIS develop and prepare standard operation procedures (SOP) for waterworks and wastewater manuals and training materials for environmental, waterworks and wastewater operators. EMGIS is also busy preparing a watersafety plan for the O.R.Tambo District Municipality. EMGIS DIRECTORS T.J.NTOZAKHE (PhD): Dr. Ntozakhe obtained his doctorate degree in Analytical Chemistry at the University of Cincinnati (USA) where he also served as a lecturer. He has worked for Sentrachem as a manager of Analytical Laboratories, during which he worked closely with SABS and gained valuable experience in quality systems(ISO 9000), good laboratory practice (GLP) and laboratory accreditation. In 1996 he served on RAF, an advisory body to the minister of Trade and Industry on laboratory accreditation policy. He has also worked for Sasol Research and Development Division (SASTECH) as a chief Scientist. Dr. Ntozakhe is currently in the Department of Chemistry at Walter Sisulu University of Science and Technology. He has researched extnsively on drinking water quality, waste water management, waste management, river health, the traditional medicinal plants and essential oils. His business acumen in unparalleled. N. MYEKO obtained honours degree in Geography with a distiction in Water Resources Management at Walter Sisulu University. Presently she has register for a Masters degree (analysing water, soils and herbal plants). She also obtained a master diploma in Human Resources Management at Rand Afrikaans University . Her company provided services on medical waste management. She hasresearched on drinking water quality, waste management, river health, and the traditional medicinal plants. Contact details P O Box 1417, Mthatha, 5099 Cell: Ms Myeko 083 2977226; Dr Ntozakhe 082 6919282
Index of Advertisers Company Page Amanziflow
130
Amathole District Municipality
124
Ambio Environmental Management (Pty) Ltd
8 & 56
Anglo American South Africa
38 & 151
Avis
Inside Back Cover
Ballam-Waterslot (Pty) Ltd
105
Capricorn District Municipality
96
Centre for Environmental Management, University of the Free State
111
Chemical & Allied Industriesâ&#x20AC;&#x2122; Association
77
CSIR
Back Cover
Department of Water Affairs
2 & 41
Environmental Management & Geographic Information Systems Training (EMGIS) 162 Energy Sector Education and Training Authority (ESETA)
140
GE Water
101
Green Building Conference & Expo 2010
62
Grinaker-LTA
6 & 33
Hanna Instruments
161
Iliso Consulting
133
Instituto Superior De Relacoes Internacionais (ISRI)
118
Intaka Tech
70
Maquassi Hills Local Municipality
23 & 24
P & B Lime Works
12
Senter 360
14
Stellenbosch Municapality
53
Sustainable Handbook Series
148
Sustainable Transport & Mobility Conference 2010
82
Sustainable Water Conference & Expo 2010
Inside Front Cover
The Development Bank Southern Africa
4, 65 & 112
UGU District Municipality
90
University of Johannesburg
85
Water and Sanitation Service South Africa (WSSA)
134
Zimbabwe National Water Authority (ZINWA)
78
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AV/1034/09
Making a difference for the long term. At Avis we acknowledge that our business has an impact on the environment. That is why for the past two years we have invested in water recycling plants at our major airport locations, saving our country 95 000 000 litres of water every year. We have also measured our South African businesses carbon footprint and taken steps to becoming a CarbonNeutral速. Company. Because we care, we are changing the way we do business so that our world would be a better place for our children and theirs.
www.avis.co.za or call 0861 021 111 B-BBEE Level 2 Contributor and Value Adding Enterprise
Avis saves 95 000 000 litres of water per annum. Water is South Africa’s most precious resource and one which requires the utmost conservation attention by industries where it is consumed in significant quantities. You can imagine that the car rental business is a high consumer of water and probably the highest in the service (non production) industry, where on average in South Africa, around 8000 vehicles are washed every day. That is a lot of water and most of this simply goes down the drain….., but not so at Avis. When Avis set out to upgrade its major facilities at Johannesburg, Cape Town and Durban airports over the past two years, a decision was made to invest in equipment and processes that would recycle the water used to wash it’s vehicles, thereby conserving this precious resource. This focus culminated in the following actions undertaken since 2008:1. The installation of car wash machines that took the least time possible and used the bare minimum of water to wash each vehicle. Here, Avis consulted with Garage Equipment Services who sourced the most modern drive through machines which washes a vehicle in approximately 45 seconds in a controlled manner which eliminates water wastage. 2. Avis further invested approximately R1,5 million to construct underground water filtration and recycling
www.avis.co.za or call 0861 021 111 B-BBEE Level 2 Contributor and Value Adding Enterprise
facilities at its three main depots (with more to follow). The used “grey” water is channeled and filtered to be over 90% clean and is re-pumped back into the system to wash the Avis vehicles. The only process requiring fresh municipal water is the final rinse arch at the end of the wash, ensuring that the vehicles come out spotless for final rental preparation. 3. At an additional cost of R400,000, Avis’ installed at its new state of the art vehicle preparation yard at Cape Town International Airport (where there are significant periods of high rain fall), a 180,000 litre underground water reservoir, which captures the “free” and clean rain water run-off from the roofs of its main buildings and then uses this to feed into the car washing and water recycling facility. As a result of the R1,9 million investment in its water recycling program at its three main depots, Avis estimates that they will save the environment (and their costs) almost just under 100 million litres of water per annum. This environmental protection project is just one of many programs undertaken at Avis, under the Avis Cares umbrella, which incorporates a 3-Pillar (Environment, Community and its People) sustainability approach to its business practice, driven from the Chief Executive through to the entire Brand Ambassador compliment within the organisation.
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Do you want to develop your career and be the best you can be? The CSIR focuses its research efforts in diverse arenas, which means that scientists, researchers and engineers have a range of multidisciplinary fields to explore. Computer scientists, for example, could find their skills applied to research efforts in anything from designing aircraft; to collecting spatial data used in townplanning; to developing algorithms for controlling the behaviour of robots.
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