Inspiring passion for water! The official magazine of
Water& Sanitation Complete water resource and wastewater management
AquaPlan
Africa
Mine Water
Agriculture game changer
The answer to reuse
Trenchless Technology A pipe bursting challenge
in the
hot seat
IoT & Automation
On the brink of a revolution
“Our new AMI infrastructure opens up the African market and gives clients the opportunity to access locally manufactured, globally sought-after technology.” Marcus Thulsidas Business Development Director, Utility Systems P12 September/October 2018 • ISSN 1990-8857 • R50.00 (incl. VAT) • Vol. 13 No. 5
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WATE R PRO D U CTS F O R THE FU T U RE
+27 10 140 3773 w w w. v o v a n i . c o . z a
Vol. 13 No. 5
SEPTEMBER/OCTOBER 2018
CONTENTS Promoting professional excellence in the water sector The official magazine of the Water Institute of Southern Africa
Water& Sanitation Complete water resource and wastewater management
AquaPlan
Africa
MINE WATER
Agriculture game-changer
The answer to reuse
TRENCHLESS TECHNOLOGY A pipe-bursting challenge
IN THE
HOT SEAT
IOT & AUTOMATION
The brink of a revolution
“Our new AMI infrastructure opens up the African market and gives clients the opportunity to access locally manufactured, globally sought-after technology”
Marcus Thulsidas Business Development Director, Utility Systems P12
September/October 2018 • ISSN 1990-8857 • R50.00 (incl. VAT) • Vol. 13 No.5
ON THE COVER One of the most robust, versatile and widely used unit operations in the treatment of wastewater worldwide is dissolved air flotation. With the growing market for wastewater reuse, the demand for these systems is expected to grow. P6
Regulars
Editor’s comment
Cover Story
The answer to reuse
3 www.sastt.org.za
4
IoT & Automation
WISA
Hot Seat
Smart water management
Dams & Reservoirs
Countering the sedimentation threat
SASTT Trenchless News
Replacing the Bath Avenue water pipe Pipe bursting with the HammerHead
Laboratories & Equipment
14
24 25
The power of demand-driven distribution What WC/WDM can achieve for your WSA
29 30
Landmark plant for Umgeni Water
33
Treatment
IoT & Automation
Harnessing IoT for drought management Changing the infrastructure space
Meters, Pipes, Pumps & Valves
Sophisticated measurement solutions A smart solution to leak detection A case for PVC-O in bulk water pipelines
Mine Water
A long-term solution A game changer in agriculture
Sanitation
Award-winning sanitation solution
36
SASTT Trenchless News
NEWS
Replacing the Bath Avenue water pipe
18
HDD and pipe bursting with Ditch Witch and HammerHead
22
18 22
Monitoring done right Setting a new milestone
Water Management
T
12
17
NCHLE RE
SS
CEO’s comment 6 Chair’s comment 7 YWP 9 A lifetime of achievement 49 Giving back to communities 50
24
Laboratories & Equipment
HOT SEAT
35 36
Utility Systems Smart water management
39 40 42
45 46
48
45
Mine Water infrastructure news
Water services authorities are seeing an increasing need to install water management devices to address growing water challenges. Marcus Thulsidas, business development director, Utility Systems, talks about how the company’s smart electronic water control devices can assist utilities. P12 infrastructure4
www.infrastructurene.ws
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LEO 5 manometer with Bluetooth Classic
RFID pressure transponder from the 21 D series
Wireless pressure transmitters with Bluetooth Smart
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Publisher Elizabeth Shorten Editor Danielle Petterson Managing editor Alastair Currie Head of design Beren Bauermeister Chief sub-editor Tristan Snijders Sub-editor Morgan Carter Contributors Marco Camarda, George Gerber, Lester Goldman, Derek G Hazelton, Valerie Naidoo, Suvritha Ramphal, Peter Townsend Client services & production manager Jayshree Maharaj Distribution manager Nomsa Masina Distribution coordinator Asha Pursotham Financial manager Andrew Lobban Printers United Litho Johannesburg t +27 (0)11 402 0571 Advertising sales Hanlie Fintelman t +27 (0)11 467 6223 | c +27 (0)82 338 2266 h.fintelman@telkomsa.net Publisher
Physical address: No 9, 3rd Avenue, Rivonia, 2191 Postal address: PO Box 92026, Norwood, 2117, South Africa t +27 (0)11 233 2600 • f +27 (0)11 234 7274/5 alastair@3smedia.co.za ISSN: 1990 - 8857 Annual subscription: R330 (SA rate) subs@3smedia.co.za Copyright 2018. All rights reserved. All articles herein are
copyright protected and may not be reproduced either in whole or in part without the prior written permission of the publishers. The views of contributors do not necessarily reflect those of the Water Institute of Southern Africa or the publishers.
WISA’s Vision
Inspiring passion for water
WISA Contacts: Head office Tel: 086 111 9472(WISA) Fax: +27 (0)11 315 1258 Physical address: 1st Floor, Building 5, Constantia Park, 546 16th Road, Randjiespark Ext 7, Midrand Website: www.wisa.org.za BRANCHES Central Branch (Free State, Northern Cape, North West) Chairperson: Dr Leana Esterhuizen Company: Central University of Technology Tel: +27 (0)51 507 3850 Email: lesterhu@cut.ac.za Eastern Cape: Chairperson: Christopher Maduma Company: Nelson Mandela Bay Municipality Tel: +27 (0)41 506 7527 Cell: +27 (0)82 300 7044 Email: citm@live.com Gauteng Chairperson: Ashwin Seetal Company: CSIR Tel: +27 (0)12 841 3477 Cell: +27 (0)82 804 2852 Email: aseetal@csir.co.za KwaZulu-Natal Chairperson: Lindelani Sibiya Company: Umgeni Water Cell: +27 (0)82 928 1081 Email: lindelani.sibiya@umgeni.co.za Limpopo Chairperson: Mpho Chokolo Company: Lepelle Northern Water Cell: +27 (0)72 310 7576 Email: mphoc@lepelle.co.za Mpumalanga Chairperson: Lihle Mbatha (Acting) Company: Inkomati-Usuthu Catchment Management Agency Tel: +27 (0)13 753 9000 Email: mbathat@iucma.co.za Western Cape Chairperson: Natasia van Binsbergen Company: AL Abbott & Associates Tel: +27 (0)21 448 6340 Cell: +27 (0)83 326 3887 Email: natasia@alabbott.co.za
editor’s COMMENT
Working with nature
T
here was a media frenzy when news recently broke that raw sewage from Emfuleni was running into the Vaal System. Images of dead fish and pollution emerged, raising concerns over the longevity of one of Gauteng’s main water sources and suggesting the Vaal may be declared a disaster area. NGO Save the Vaal has been fighting sewage pollution in the Vaal for about 10 years. In this time, the organisation has obtained nine court orders against Emfuleni Municipality – the most recent in February – which required the municipality to immediately prevent discharges of sewage, to fix infrastructure, and to report back to the court on its compliance with the order. Save the Vaal, however, alleges this has not been done. Add to this the untreated effluent from the growing surrounding informal settlements and throw in some acid mine drainage and it's a ticking time bomb. How long can we continue to pollute our water resources given the increasing pressure on our limited supply? Cape Town may be out of the worst of its drought, but the Eastern Cape is facing a serious crisis, with Kouga Dam having dropped below 7%. And with climate change now an inevitability, it is expected that we will face more serious weather events like droughts and floods, putting more pressure on our systems.
Building water-sensitive cities In addressing this issue, it is vital to look at the link between water, ecosystems and human development – a key focus at the recent World Water Week. Torgny Holmgren, executive director of SIWI, which organises the event, pointed out that water scarcity has become the new normal in many parts of the world. Decades of unprecedented economic and population growth, rapid urbanisation and climate change have led to stressed ecosystems and high pressure on limited water resources. The message out of World Water Week was this: to address these issues, societies must find and implement solutions that work with, rather than against, nature. There was optimism about an increase in new solutions borrowed from nature. These ‘green’ infrastructure solutions are inherently multifunctional and often more resilient than grey infrastructure. For example, city parks retain rain, improve the microclimate, and contribute to biodiversity. This reminded me of a presentation by professor Tony Wong at WISA 2018. He spoke of the need for integrated urban water management to create cities that are both water sensitive and liveable. This requires three things. First, cities must become water supply catchments, meaning access to water through diverse sources at a diversity of supply scales. Second, cities must provide ecosystem services, meaning the built environment functions to support the function of the natural environment. And third, cities must consist of water-sensitive communities, meaning sociopolitical capital for sustainability exists and citizens’ decisionmaking and behaviour is water sensitive. It is safe to say that most, if not all, cities have not yet achieved this. But with the growing realisation that we are all increasingly vulnerable to water shortages and extreme weather, it is evidently something we should be moving towards. While it is important to address the immediate pain points, it is also vital that we begin to look at water and infrastructure holistically, so that our cities can be productive, liveable and resilient.
Promoting professional excellence in the water sector The official magazine of the Water Institute of Southern Africa
Water& Sanitation Complete water resource and wastewater management
AquaPlan
Africa
MINE WATER
Agriculture game-changer
The answer to reuse
Endorsed by TRENCHLESS TECHNOLOGY A pipe-bursting challenge
IN THE
HOT SEAT
IOT & AUTOMATION The brink of a revolution
“Our new AMI infrastructure opens up the African market and gives clients the opportunity to access locally manufactured, globally sought-after technology” Business Development Director, Utility Systems P12
Marcus Thulsidas
September/October 2018 • ISSN 1990-8857 • R50.00 (incl. VAT) • Vol. 13 No.5
Danielle Cover opportunity In each issue, Water&Sanitation Africa offers companies the opportunity to get to the front of the line by placing a company, product or service on the front cover of the magazine. Buying this position will afford the advertiser the cover story and maximum exposure. For more information, contact Hanlie Fintelman on +27 (0)11 467 6223, or email h.fintelman@telkomsa.net.
COVER STORY
The answer to reuse One of the most robust, versatile and widely used unit operations in the treatment of wastewater worldwide is dissolved air flotation. With a growing market for wastewater reuse, the demand for these systems is expected to rise accordingly.
T
he importance of dissolved air flotation (DAF) systems in modern water treatment processes cannot be over-emphasised, explains Niel Kruger, process engineer, AquaPlan. Due to their highly efficient and cost-effective removal of suspended solids (SS), chemical oxygen demand (COD) and phosphorus in wastewater, DAF systems have now become an intrinsic part of the process of treating wastewater.
Niel Kruger, process engineer, AquaPlan
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A well-placed and well-designed DAF system offers unprecedented advantages for both upstream and downstream processes, as part of both the removal of pollutants in the wastewater, as well as the protection of membrane processes downstream of the DAF. AquaPlan has developed a robust, simple, easy-to-operate and versatile range of skid-mounted DAF systems, which encompass the dissolving of air, recirculation of white water, as well as the distribution and separation of particles in one simple system. The applications are broad, with the material of construction ranging from epoxy-coated carbon steel to 316 stainless steel – the material of choice in food and beverage and paper production applications. AquaPlan’s DAF systems have been utilised in the water treatment processes of industrial effluents from oil refineries, chemical plants, paper mills, and food and beverage processes. Two of the company’s most recent installations serve as pretreatment in the preparation of drinking water from the polluted Vaal River as a source, as well as the production of drinking water from raw sewage water in the Western Cape. According to Kruger, AquaPlan’s skid-mounted systems are
AquaPlan’s DAF systems are skid-mounted, versatile, robust and easy to operate
well suited for installation into current processes as a pretreatment to both ultrafiltration (UF) and reverse osmosis (RO) systems, as well as post-treatment to biological processes such as membrane biological reactor (MBR), moving bed biofilm reactor (MBBR) and sequential batch reactor (SBR) systems. Coupled to well-designed biological systems, the removal and carry-over of suspended and organic matter to post-treatment processes pose a direct threat to the longevity and sustainability of membrane processes. The DAF system is very effective in removing oils,
COVER STORY
The DAF system is quick and easy to install, and covers a very small footprint
fats, grease, organic compounds, and very fine colloidal suspended solids in one easy process, which increases the lifespan of membranes. The future is reuse Kruger believes the trend to incorporate DAF systems into wastewater treatment processes will accelerate over the next few years as the pressure to reuse wastewater grows exponentially. “South Africa is an arid country with a low average rainfall, where reservoirs and water storage capacities are extremely low. With the projected population growth over the next 10 years, coupled with the effects of global warming to shifting weather patterns, the use and reuse of wastewater in South Africa as a way to augment natural sources is an excellent opportunity for sustainability,” says Kruger. However, wastewater typically comprises all the unwanted and toxic elements with which a design engineer could be confronted, including organic and suspended matter, viruses, bacteria, and oils and fats – all of which need to be removed from the water source. A well-positioned DAF system is absolutely critical in removing most of these constituents, explains Kruger. The biggest challenge to this process is the protection of the equipment against fouling and blocking, as well as guarding against high energy and maintenance costs within the system. Placing individual unit operations in the most advantageous and sustainable positions will effectively mitigate these risks.
The AquaPlan DAF system comprises a fully integrated air saturation and recirculation pump system, flotation basin, lamella-pack integrated settler tubes, scum flotation system, and conical sludge removal underflow, all onto one integrated skid-mounted frame, ready for installation. The system is simple and quick to install, and covers a very small footprint for large flow rates compared to conventional clarification systems.
The system can be used to treat industrial effluents, polluted water and even sewage for drinking water
Energy efficiency The process is extremely energy efficient and the float collection mechanism has no moving parts since waste floats can be lifted off with a simple and automatic hydraulic jump. The equipment is placed on a simple and cost-effective concrete slab, or plinth, by simply lifting the complete system into position. The DAF system can be installed and commissioned within two to three days, as the commissioning process is quick, simple and efficient. Its low maintenance costs and readily available, cost-effective spare parts are welcomed in the industry. As a result, solutions can be quickly and easily put in place to boost water resources. “The availability of both ground and surface water resources will diminish if not managed more carefully. The reuse of wastewater will be an absolute necessity as an alternative resource when the normal sources run dry or are contaminated,” says Kruger. Changing mindsets South Africa has many large, wellestablished wastewater works situated near city metropoles, which will likely provide treated water sources to communities in the future. However, there is work to be done in changing mindsets and embracing reuse. “While more pristine natural resources diminish and environmental degradation of sustainable habitats becomes more evident, as a direct result of industrial activity, the shift to utilise wastewater for drinking water will grow exponentially. The technology already exists to produce drinking water from a wide arrange of non-potable sources, such as acid mine drainage, seawater and raw sewage at city outfall points. “As responsible citizens, each person has a vested interest not only to minimise waste, but to utilise our waste streams in environmentally responsible ways, such as reducing our carbon footprint and conserving energy. Drinking our own treated waste may not sound plausible at this point, but it is indeed our future,” concludes Kruger.
www.aquaplansa.co.za S E P T /O CT 2018
5
WISA • CEO’s Comment
The WISA 2018 Biennial Conference was well attended, and had many interesting sessions and discussions. The level of discussion and debate was very inspiring, and it was wonderful to see such discourse, albeit in a ‘safe’ environment – where frank discussion among colleagues is encouraged and solutions are being sought.
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his was very evident, as many sessions were packed to the brim and debates went on long after sessions closed. This is the advantage of such conferences and workshops – they provide an avenue for our sector professionals to provide and obtain advice, as well as share in their challenges and daily frustrations. These challenges, we are told, are becoming increasingly common among members, and sadly align closely with other troubled sectors. Hugely debated topics at the WISA Conference included governance and leadership and, while these are widely discussed challenges generally, a common concern was
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Working to safeguard public interest that these topics could not be freely discussed within organisations, or around the boardroom table. Unfortunately, the freedom to discuss these crucial topics is not common. And yet, according to Harvey and Mason (1995), sector professionals have a duty to protect and safeguard the public interest, and are therefore obligated to discuss these topics. Supporting sector professionals WISA is committed to increasing and improving the number of events where sector professionals can continue such lively debate. In an effort to improve governance, we will also be looking to create awareness of organisations and hotlines where sector professional can report any troubling activity. Our website has a section where you can access this link, which will hopefully assist you in safeguarding the public. We understand the real fears and concerns you, as professionals, have and hope we can assist you in this regard. We encourage our members to comply with the Protected Disclosure Act (No. 26 of 2000), and ensure that they have measures in place to deal with employee disclosures. These procedures should be set out in a company policy that is made available to all employees. Whistle-blowing policy The aim of any whistle-blowing policy is ultimately to create a culture of openness
and accountability without fear of reprisals or occupational detriment, to ensure that employees report knowledge of any irregularities so that management can take the necessary steps to investigate and/or deal with them. A whistle-blowing policy should include information regarding matters that are to be disclosed in terms of the policy, as well as the procedures that need to be followed when making such disclosures. The policy should also provide guidance on the amount of information that should be provided when making any disclosures. For example, the type of conduct that constitutes the alleged irregularity, the names of those individuals involved in the alleged conduct, dates and places of occurrence, as well as how the information came to the relevant employee’s knowledge. In addition to making the policy available to all of their employees, employers should ensure that they provide training to their employees on the policy. As Madiba said, “We can change the world and make it a better place. It is in your hands to make a difference.” Dr Lester Goldman, CEO, WISA
WISA
Chair's comment
Women in water and society
A
s we continue to reflect on our progress, Women’s Month should be about enlightenment rather than ‘boxes’. What do I mean by this? Women have the right to choose their path, not based on traditional roles or stereotypes but on the possibility to live their best and most productive life. So, if one brings to attention gender issues by creating Women’s Month or Women’s Day, is that enough? In this regard, I found the take-home messages from What Works. Gender Equality by Design, a 2016 book by Professor Iris Bohnet of Harvard, most enlightening. First, she highlights – through her studies – that in order to create change, one has to ‘design for change’. In this regard, the government policy in South Africa has encouraged gender equality. In the water sector, there is a legislative and policy framework in place that supports equality of opportunity and advances women through the Employment Equity Act (No. 55 of 1998). More specifically, the water sector developed a National Implementation Strategy and Action Plan (2006–2010) to mainstream gender in the water sector. A 2009 Water Research Commission (WRC) study evaluating gender mainstreaming in water user associations reported that while there were wellthought-through policies and legislation on gender, there was a problem in the translation of policies into practice. The top-down approach for poor black farmers was not in line with the vision and there was a general lack of understanding of the concept of gender equality and mainstreaming. Furthermore, mainstreaming was driven only through
Dr Valerie Naidoo, chair, WISA
The 9th of August is considered a turning point in history for South Africa when 20 000 women from all walks of life decided to protest against unjust laws. Through courage and humanity, these women shone a spotlight on the need for a society that was based on principles of justice and fairness. quotas without creating an enabling environment for women. So, the strategy drove shifts in numbers and representation but did not drive the shifts required to empower women. For
example, since women did not own land and water rights, they were not gaining any benefits from their involvement, like influencing decisions on allocation of water resources. This highlights that there is more work to be done and that it is important to accept that more innovative design approaches (data, experimentation and evaluation) are required to test mainstreaming opportunities. Designing for change If we are to mainstream gender equality even further, then this ‘design’ has to enter corporates as well as society. For society, this is not just about mechanisms that change political representation but also the conversations and awareness that are raised at a family and community level. Bohnet raises the point that bias is common and uses the following example to highlight it: “In 1970, only 5% of the performers in the five best American orchestras were female. Now, more than 35% are. This didn’t happen by accident. Following the lead of the Boston Symphony, orchestras shifted to blind auditions, wherein judges hear musicians play but don’t see them. Directors always believed they cared only about a musician’s skill. ‘Unconscious’ bias led them to select a majority of men. When they auditioned musicians behind a screen, they chose differently.” She speaks of the ‘representative heuristics’ that executives apply for promotion and hiring. Generally, men are more likely to be hired for tasks that seem masculine, like math, and women are more likely to be hired for tasks associated with female stereotypes, like verbal skills. However, if one has to look at candidates comparatively, this bias falls away and people are then evaluated S E P T /O CT 2018
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WISA
Chair's comment
on performance. Global statistics bear this trend, which shows the current ceiling for women is about 15% to 25% of business leadership roles. A BusinessTech and Pew Research Centre survey compared male and female leadership attributes and found that women outperformed men on many attributes such as: (1) leading by example, (2) being honest and ethical, (3) communicating in an open and transparent way, (4) bringing out the best in others (providing guidance and mentorship to younger employees),
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and (5) providing fair pay and benefits. Men came out strong on risk taking and handling crises. It is important to understand that organisations and companies should be shaped with different risk-aversion levels to enhance performance and equality. Organisations also have to design for ‘de-biasing’ and disrupting social norms, such as people learning that bias is possible, being aware why people are driven towards homogeneity, and crafting programmes to train, coach and analyse behaviour. One can also use role models to shape expectations, break stereotypes, and open up possibilities. A study done by the WRC in 2010 suggested that strengthening the following criteria would improve the success of women in the water sector via: access to opportunities to increase functional capabilities; access to education and continuing education that instils confidence and independence, dedication and hard work; support
for personal and professional growth; provision of a stimulating environment that values innovation and creativity, among others; social capital development through collaborative networks; and nurturing leadership and leaders. WISA’s strategy Finally, let me reflect on the Water Institute of Southern Africa and its strategy for an inclusive water sector. In this regard, we see an interesting trend in our membership numbers. In our membership group of 40-year-olds and above, the percentage breakdown for male to females is 80:20; while for the 20-to-40-year-olds, the percentage breakdown for males to females is 59:41. This shows a marked change in our demographics that are in line with policy recommendations and shifts, and bodes well for the future. In terms of overall membership, WISA has a percentage breakdown of 71:29 male to females. So, there is still work to be done but we are moving in the right direction.
Meet
WISA Y WP
the 2018-2020 YWP-ZA National Committee
Outgoing lead (2016-2018)
Lead (2018-2020)
Nora Hanke-Louw
Suvritha Ramphal
“The water sector is rich with possibilities and opportunities. I encourage all YWPs to network, explore and get involved.” Water sector manager, Energy and Water Sector Education Training Authority
“Keep something to remind you of why you’re on the path to success, because the pathway to success is not always the easiest to stay on.” Water sector programme officer, Danish Embassy
Finance lead and International Water Association’s emerging water leader steering committee member
Vice-lead Ashton Mpofu “The present water crisis is real and the future looks challenging. Let us act now and channel our youthful energy towards a greener future. It depends on us.”
Lloyd Fisher-Jeffes Water resource engineer, Aurecon
PhD candidate, research assistant and part-time lecturer, Cape Peninsula University of Technology
Coordination lead
The new Young Water Professionals national committee has taken office and I would like to take this opportunity to introduce our new committee members. By Suvritha Ramphal*
Chanelle Mulopo PhD candidate and parttime lecturer, University of KwaZulu-Natal
Imvelisi lead Lee-Ann Modley “Discipline is the bridge between goals and accomplishments.” – Jim Rohn
2019 YWP-ZA conference lead Lindelani Sibiya Water treatment process technician, Umgeni Water
PhD candidate and lecturer, University of Johannesburg
S E P T /O CT 2018
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WISA Y WP
KwaZulu-Natal lead
Eastern Cape lead
Londiwe Satimburwa
Sipho Mashiyi
Project technician, eThekwini Municipality
Civil engineer, Aurecon
Gauteng lead Vanessa Weber “A true young professional leader is one who does not create followers but rather empowers and creates more young professional leaders.”
Limpopo lead Vuledzani Pearly Maiyana
Representative: West and Central Africa, Milton Roy
Water quality scientist, National Department of Public Works North-West lead Guzene O’Reilly PhD candidate and lab manager, Fourie’s Poultry Farms
Western Cape lead Paul Viljoen Water pollution inspector, City of Cape Town
Mpumalanga lead Zanele Sifundza Water care technician, Regional Department of Public Works
T
he YWP-ZA welcomes the new restructure and empowerment platform image. We understand that this will be a learning exercise for the WISA community and its partners, and have encouraged our network to support this with an open mind. We can proudly communicate that some YWP-ZA provincial leads have already embraced WISA’s new ethos of working collaboratively on events and future planning. We look forward to working much more closely with WISA branches and technical divisions across the country going forward. Upcoming national activities Annual Strategic Session The YWP-ZA National Committee will
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convene in October for its annual strategic session. This is the first session in the two-year term and will be an interesting one as the committee navigates through its two-year plan, taking cognisance of the WISA restructure and new rules of engagement. 2019 Conference The next YWP-ZA conference will take place in 2019 in KwaZulu-Natal. The conference will be managed by conference chair Lindelani Sibiy (lindelani.sibiya@umgeni.co.za). More information about the conference is to follow by the end of 2018. Thank you to our members The YWP-ZA National Committee would
like to extend a huge thank you to the young water professional community in South Africa. It is through our commitment to and passion for creating good practices in water that we won the WISA Aqua Vita Est Award at the WISA Conference held in Cape Town in June 2018. We will continue to deliver excellence to our members and the broader international community. Please continue demonstrating your support by playing an active role at your regional activities and events. Get in contact with your regional lead or find out more on our website www.ywp-za.org.za.
*Suvritha Ramphal is the chair of the South African Young Water Professionals.
Chest Waders
HOT SEAT
Smart water management Water service authorities are seeing an increasing need to install water management devices to address growing water challenges. WASA speaks to Marcus Thulsidas, business development director, Utility Systems, about how the company’s smart electronic water control devices can assist utilities.
The internet of things (IoT) and automation are revolutionising the water monitoring and billing environment. What are the opportunities and advantages in Southern Africa? MT One of the market’s biggest pain points is the efficient management of the reticulation system. In many instances, there is not enough data to optimally use the resources available within a local authority for this task. There is a growing need for data to guide decision-making and streamline processes, and the move towards IoT and automation supports this. Our advanced metering systems offer utilities many advantages, including advanced warnings and alerts on things like tampers and leaks, so that resources can be effectively distributed. Our solutions also
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aid local authorities with driveby and remote meter reading and control systems. This not only allows for faster and more accurate data capturing, but also allows authorities to monitor infrastructure in high-risk areas where access is limited. Accuracy is vital when it comes to data. We are NCRS approved to function with multiple brands of measurement elements and our measurement controls are of a C-Class nature, meaning they are accurate to within 2% on flows between 15 ℓ/h and 3 000 ℓ/h.
One of the biggest challenges for South African water utilities is accurate billing. How do Utility Systems’ products address this challenge? Much of South Africa’s water billing systems rely on
estimation, largely because of limited resources available to perform meter readings as well as inaccessible and unreadable meters. Our products – like the Water Management Device (WMD), utiliMeter and Aquadata – allow municipalities to perform unscheduled meter reading with drive-by, walk-by and remote systems. We utilise advanced meter reading (AMR) and advanced metering infrastructure (AMI) to deliver accurate data in near real time, providing municipalities with the most accurate billing data. We tailor our solutions to meet the particular needs of each client. One of our largest clients, the City of Cape Town, is now using over 200 000 AMRenabled devices to provide more accurate meter readings to its customers and ultimately increase its revenue.
water consumption. We also offer prepaid metering solutions with AMR data collection, ensuring municipalities get upfront payment and know exactly how much water is used at a particular point. Utility Systems developed the first commercially available Standard Transfer Specification (STS) Association approved prepayment water management device. When linked to a pulse output water meter, the WMD enables two-way communication, configuration and valve control as well as the option for STSapproved prepaid water supply. Our system also caters for free basic water requirements at a device level, meaning everything is managed by the device itself. It is able to dispense a predetermined amount of water daily
How can this translate into increased revenue collection? By reducing estimation with accurate data, municipalities can bill more accurately for
Marcus Thulsidas, business development director, Utility Systems
HOT SEAT at scheduled times, thereby providing the ability to limit a consumer to a finite level of supply. It also comes with a topup option for those who wish to pay for additional water over and above their free allocation.
What about bulk water management? The size of our solution offerings goes up to 50 mm. Our bulk metering solution, capable of time and volume switching, has been very successful in school environments where water consumption and losses need to be managed. We have implemented our bulk meters in several KwaZulu-Natal schools with great success. These are programmed to cut off supply between 17:00 and 05:00 to reduce losses from leaks and open taps, resulting in financial savings of up to 40% on the water bill.
utiliMeter
South Africa is faced with a very high non-revenue water figure. How can your smart meters assist with leak detection? Each device continuously monitors consumption. If there is constant consumption of over 5 ℓ/h for 24 hours, the device flags it as a possible leak and will send an alert out to a data concentrator or the user interface of prepaid units. This allows users and authorities to take early action to address leaks.
available for download from the Play Store for Android devices. These fresh and dynamic apps tie in perfectly to our various solutions. The first is utiliRead, which provides an easy tool for reading meters, learning the route on which meters are to be read, recalling the route, and identifying unread meters and meters with an alert status. The app is perfect for drive-by meter readings and can be loaded on to the mobile device of the driver who collects meter readings by driving the set route. Data can be exported in text format for easy incorporation into an existing billing system. The City of Cape Town has just approved this app for city-wide deployment with an install base of over 200 000 devices. Our service app, utiliPro, is an in-field management app that allows technicians to manage and configure water management devices in the field. utiliPro is currently being rolled out to approximately 500 terminals in Cape Town, as the first step in moving from AMR to AMI. This shift will, in the future, allow for the remote management, control and reading of all meters under the utility’s management. Lastly, our new consumer app, utiliApp, gives users the ability to monitor The utiliMeter is AMI-enabled for remote control, configuration and management
utiliMeter with antenna
their own consumption, view their device status, load prepaid water credit and monitor their credit in areas where the local authority has adopted our systems.
How is AMI changing the metering environment and what are the benefits to both the utility and the customer? AMI essentially offers an integrated system of smart meters, communications networks, and data management systems that enable two-way communication between utilities and customers. Globally, we are seeing more requirements for automation at end points, as utilities look to remotely diagnose and debug issues in the field. Our new utiliMeter product is AMI-enabled to allow for bidirectional communication in near real time. This allows for the remote control, configuration and management of any utiliMeter on a fixed network, located anywhere, via the cloud or over a local private network. It also includes all of our other functions and features
like free basic water, AMR and prepayment, while significantly reducing the time it takes to get meaningful data such as tamper, leak and meter readings back to the service provider.
Some utilities still struggle with understanding and integrating smart metering. How can you simplify the integration process? Most of our solution offerings are stand-alone and the data that we output is through an open platform, making integration into existing billing platforms fairly seamless. When it comes to data integration, we take the lead from the local authority on what their requirements are and advise them on the best approach for project deployment and integration. We also have an API available for municipalities to integrate into.
What can we look forward to from Utility Systems? We are a dynamic, ever-evolving company. Our new AMI infrastructure opens up the African market and gives clients the opportunity to access locally manufactured, globally soughtafter technology. There are not a lot of products available that can perform the same multicore functions as Utility Systems’ products at multiple levels. We are always looking at the pain points and challenges, and how we can adapt our technology to address these.
Utility Systems is launching some exciting new apps. Please tell us about these. We are very excited about our three new apps, which are now
www.utility-systems.co.za S E P T/O CT 2018
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Dams & Reser voirs
Countering the sedimentation threat Left unchecked, sedimentation build-up is the silent thief of our water resources, but there are effective measures to combat this. By Peter Townsend*
LEFT A badly silted weir at an irrigation canal offtake, with denuded river bed downstream BOTTOM LEFT Large spillway scour gate on the Runde River, Zimbabwe
150 million cubic metres
S
ediment accumulation is the scourge of South African rivers and dams. It never ceases and is continuously filling our dams and waterways, thereby reducing available
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storage capacity needed to meet our ever-increasing demand for water. The recent droughts have denuded the vegetation and the subsequent floods wash down thousands of tonnes of sediment. It is estimated that in the order of 150 million cubic metres of sediment accumulates in our many dams every year. This is equivalent to losing one large dam to sediment annually. Many dams and weirs have already lost their function due to silting up. This is a large loss of capital expenditure. Efforts to remove the sediment by excavation and dredging are prohibitively expensive and not feasible, depending on the size of the containment. While most dams and river weirs are provided with sluice gates to scour out sediment, they have proved to be effective only for a small, localised cone of scouring around the sluice gate and do not desilt the dam or weir. The reason they are ineffective is that the sluice gates are mostly manually controlled and are not opened when the flood is running. Once the sediment settles and consolidates, it is difficult to sluice it out later, and particularly once reeds have established in the sediment and anchored it with roots.
It’s estimated that around 150 million cubic metres of sediment accumulates in our dams every year
25 years The Tswasa weir system on the Groot Marico River, which has a number of scour gates and crest gates to keep the pool feeding the pumping station relatively free of sediment, has been working well for more than 25 years
Sediment buildup is quietly, but increasingly, throttling our bulk water capacity and effective measures need to be implemented
Dams & Reser voirs
FROM LEFT TO RIGHT Scouring out on the Nsuze River weir for a pipe offtake to water treatment works in KwaZulu-Natal Larger scour gate for Neckartal abstraction works in Namibia Large scour gate for a 4 m wide by 2.3 m high scour tunnel in Namibia
South Africa
It then requires mechanical means to remove it. Not only do dams and weirs act as traps for sediment, but they also prevent the transportation of much needed sediment downstream for the aquatic life in the river, as well as to stabilise the banks against further erosion.
Automatic gates Fortunately, there are automatic scour gates developed in South Africa, which largely overcome sedimentation build-up in river weirs and small dams. These gates, produced by Amanziflow Projects, are designed to open when the flood runs so that sediment, in either
Dams & Reser voirs
suspension, or rolling on the riverbed while it is in motion, passes through the scour tunnel, the wall and then settles downstream where it belongs. These gates effectively keep weirs relatively free of sediment. Once the flood has passed and the water level recedes, the scour gates will open automatically to retain the full supply level in the weir or dam. It is also possible to fit these scour gates retroactively into existing weirs and low dam walls to allow the sediment to be sluiced out with successive flushes. This will recover a large amount of lost storage and, once recovered, it will maintain that level of storage during future floods. This would be useful, for example, in recovering storage in the Shongweni and Gilbert Eyles dams in KwaZuluNatal, which are almost totally silted up, as well as for many other similarly highly silted dams and weirs around the country.
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These gates have been used effectively in South Africa and neighbouring countries to keep offtakes relatively free of sediment from rivers to pump stations, canals, and penstocks. The scour gates range from as small as a 0.6 m wide by 0.3 m high scour gate in the Tugela River for a pump offtake, to a large 4 m wide by 2.3 m high scour tunnel for river abstraction for irrigation on the Fish River in Namibia. Guideline recommendations While these types of automatic scour gates keep the abstraction areas relatively free of sediment, much larger automatic scour gates are required to keep the whole containment behind the weir relatively free of sediment. The guideline is to provide an automatic scour capacity to pass the 1:2 year occurrence flood peak. This requires more such scour gates. A prime example is the Tswasa weir on the Groot Marico River, which has a
number of scour gates and crest gates to keep the pool feeding the pumping station serving Gaborone relatively free of sediment. The system has been working well for more than 25 years. The other alternative, depending on the circumstances, is a large gate capable of passing large flows through the weir. One such gate is installed on the Runde River in Zimbabwe to effectively keep the weir free of sediment. This is a barrage-type gate 12 m wide and 4 m high. Sediment build-up is quietly, but increasingly, throttling our bulk water capacity and effective measures need to be implemented to either increase the dams’ capacity to offset these losses, or remove sediment by successive sluicing and then to ensure that further sediment build-up does not occur.
*Peter Townsend is the managing director at Amanziflow Projects.
c hle n e r
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www.sastt.org.za
NEWS
Replacing the Bath Avenue water pipe
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HDD and pipe bursting with Ditch Witch and HammerHead
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SASTT Trenchless News
Replacing the The replacement of a water line on Bath Avenue in the busy Rosebank area required an innovative trenchless solution designed to overcome numerous challenges. By Marco Camarda*
Bath Avenue
water pipe
T Due to the works being in the carriageway of a major route in Rosebank, health and safety was a constant concern
he establishment of The Tyrwhitt, a mixed-use commercial and residential development on Bath Avenue in Rosebank, required the upgrading of the water reticulation line servicing buildings on Bath Avenue. The building contractor, Probuild Construction Group (PCG), began the water pipe replacement by commissioning a comprehensive ground penetrating radar (GPR) survey to locate the 100 NB (127 mm OD) steel water line running inside the carriageway of Bath Avenue. The GPR survey was used to locate the exact location of the steel pipelines, all lateral lines, erf connections, and other adjacent services adjoining and intersecting the steel water pipeline. When the GPR survey was completed, it was found that the pipeline, which project engineers .kce Consulting had originally thought was located on the sidewalk of Bath Avenue, was actually approximately 1.5 m into the carriageway of the road. This posed numerous problems to both PCG, who relied extensively on Bath Avenue as its main access to site for materials and equipment, and .kce Consulting, who had to come up with a more innovative method of replacement of the steel water pipeline. A trenchless solution After several visits to sites and a desk survey of numerous methods of working around the replacement of the The Terra Hydrocrack HC 600 S+ pipe bursting machine
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Bath Avenue steel line, the engineers eventually advised PCG to consider going trenchless. It was then decided that the 800 m long section of steel pipe was to be replaced by a trenchless method of pipe bursting using a Terra Hydrocrack HC 600 S+ static rod pulling kit. However, because the existing steel pipe was made of mild steel, and therefore very malleable, and buried only about 700 mm deep, conventional static rod puller cutting tools could not be used. Because of this, multiple trenchless contractors had turned down the R1 million project to replace the pipeline between Jellicoe Road and Bolton Road. The scope of the specialised subcontract works included the supply and installation of a new 160 PE 100 PN 16 HDPE pipe, a temporary bypass piping with temporary connections to consumers during works, as well as reconnecting these connections to the newly installed HDPE pipeline. Trenchless Technologies took on the challenge and employed a steel roller cutter in order to cut open the steel pipe. However, it was important to avoid heaving of the tarmac surface during pipe bursting due to the shallow depth of the steel pipe. The roller cutters had to be inverted such that the splitting of the steel pipeline and displacement of soil material happened in a downward, sideways direction instead of upwards towards the surface of the tarmac. This worked superbly. PCG undertook all excavations for launch and reception pits, including lateral connections. It also had to arrange for water shutdowns with the affected Johannesburg Water (JW)
SASTT Trenchless News
depot, as the work could only be done in 100 m sections due to traffic regulatory requirements from the Johannesburg Roads Agency. The arrangement and securing of these water shutdowns was always a challenging task, as the 100 NB steel pipeline serviced reticulated water
LEFT Cutting tool cutting steel pipe ABOVE Cutting tool entering steel pipe RIGHT Cutting tool exiting steel pipe
to the Mall of Rosebank, a number of hotels, as well as key residential buildings in Rosebank. The JW depot, with its
mandate to ensure continued water supply to all of these clients, had an extremely stringent shutdown regimen that could not be deviated from. Each shutdown could only last for a maximum of six hours. PCG was also responsible for the removal, reinstatement or special
WINNER SASTT AWARD OF EXCELLENCE 2017 FOR WORLD-FIRST PIPE REAMING IN TSHWANE
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YEARS
Overcoming challenges Due to the works being in the carriageway of a major route in Rosebank, health and safety was always a concern. PCG was responsible for instituting proper health and safety practices to ensure the safety of workers and the public. There were only a limited number of open excavations that could be left open on-site at any single point. Another challenge encountered was loss of pressure to water users dependent on the reticulation line during bypassing of the main steel line. While it is standard practice to bypass water systems arrayed into a ringfeed by blanking of the main steel line at the points of intersecting streets, this did not always work. This was because of aged supporting water infrastructure in the ring-feed system as well as, in some cases, other buildings having very old or malfunctioning water fittings. As a result, blanking of the main line could only be undertaken under strict permission from the JW depot. Despite these challenges, the steel water pipeline has now been replaced and the local water users along Bath Avenue are now enjoying the Erf connection use of a newly refurbished water pipeline from what was a very difficult project. The use of trenchless methods of pipe bursting proved to be less disruptive, cheaper and well suited to the situation on Bath Avenue.
*Marco Camarda is the GM of Trenchless Technologies cc.
SASTT Trenchless News
HDD and pipe bursting with Ditch Witch and HammerHead Crossing under roads, buildings and rivers to deliver services is an area where trenchless drilling techniques offer a unique advantage for new and upgraded infrastructure. This is especially the case when it comes to pipeline replacements, with pipe bursting being one of the preferred methods.
W
ithin the world of trenchless technology, Ditch Witch is a household name in the construction industry and this American OEM continues to push research and development boundaries. This is underscored by the fact that seven new models in this class have been launched in the past 17 years. The range is supplied and supported locally by Southern African dealer ELB Equipment, which, together with Ditch Witch, is focused on building the machine and allied product solutions footprint. The full trenchless Ditch Witch line-up is available on order, with ELB currently fielding selected models. These include Ditch Witch’s smaller horizontal directional drill (HDD) rigs, such as the JT10 and JT20, which are compact yet powerful machines that perform well in tight jobsites. At the other end of the scale is the high-production JT100. Ditch Witch’s JT10 has 40 kN (9 000 lb) of thrust and 44.5 kN (10 000 lb) of pullback force, and features a heavy-duty anchor system. In turn, the JT20 delivers 75.6 kN (17 000 lb) of thrust and 89 kN (20 000 lb) of pullback force. The flagship JT100 model has the power to meet large-scale pipeline projects, such as river crossings and larger-diameter installations, delivering 331 kN (70 000 lb) of thrust and 445 kN (100 000 lb) of pullback. With its infinitely variable rotary drive, the JT100 claims to be the only drill in its class that can truly match spindle speed and torque, enabling it to power through virtually any soil conditions. “A key market at present is the fibre-optic
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telecommunications sector,” explains Phillip McCallum, product manager: Ditch Witch at ELB Equipment and a board member of the Southern African Society for Trenchless Technology. “Alongside this, our goal is to expand our presence in the water and sewer segments, where there are major opportunities for trenchless applications.” ELB Equipment will be showcasing a range of solutions at the upcoming No-Dig South Africa 2018 international trenchless technology conference and expo, being held in Cape Town during October.
For pipe bursting applications, there are three HammerHead Hydroguide models available, which provide 3.4 t, 11 t and 20 t of pulling power, respectively, for pipes ranging from 152 mm to 762 mm in diameter
Hydroguide winch systems Complementing Ditch Witch’s drilling rigs is the HammerHead range. Contractors can choose between lateral, pneumatic or static pipe bursting systems, all of which are available from the product distributor ELB Equipment. “Pipe bursting follows the path of the existing utilities, reducing utility strike risks and eliminating up to 85% of excavation work compared to opencut methods,” he points out.
Ditch Witch’s JT10 is the second smallest model in the drilling fleet, yet it’s still very powerful. The machine is capable of 44 kN of pullback force, and features a heavy-duty anchor system
SASTT Trenchless News
Alongside its trenchless drilling suite, Ditch Witch has also developed a vacuum excavation range
Benefits of pipe bursting • Proven replacement method that follows the existing path of the installation • Significant risk reduction regarding potential damage to adjacent services • The preferred trenchless method for increasing pipe flow and diameter • The only rehabilitation method that installs new pipe of the same or larger diameter in the same path • Major reduction in engineering and design costs
HammerHead offers eight pneumatic bursting tool heads, ranging from 130 mm to 600 mm, capable of installing HDPE pipe from 150 mm to 762 mm. In turn, there are three HammerHead Hydroguide cable winch models available that provide 3.4 t, 11 t and 20 t of pulling power, respectively, depending on the pipe diameter and geology. The bursting head fitted to the mole tool bursts the damaged pipeline and pushes the fragments into the surrounding soil. As the tool bursts the pipe, new product of the same or larger size is pulled through by the Hydroguide unit stationed at ground level. The static system, which uses a series of interconnecting rods, is well suited for bursting and splitting the toughest of pipes, including ductile iron, and is the preferred method for the replacement of gas and water mains. Recent local projects where Ditch Witch HammerHead technology has been employed include a potable water pipeline replacement programme in Tembisa, Gauteng, where a HammerHead Hydroguide HG12 was employed. Here, a 70 m pipeline section was replaced in 38 minutes. “A key advantage of pipe bursting is that it lets you install the same or a larger-sized pipe in a fast and efficient manner, with minimal disruption,” says McCallum. A popular option for smaller works is the HammerHead PortaBurst PB30 Gen 2 unit, designed for replacing 50 mm to 160 mm lateral pipes. Equipped with 30 t of pulling force, the PB30 operates at 207 bar and the system can be powered by a backhoe, compact excavator or any other portable
hydraulic power pack. The optimal distance is between 30 m and 50 m. Alongside its trenchless drilling suite, Ditch Witch has also developed a vacuum excavation range, among its other innovations, with the FX30 and FX65 included in the line-up for the Southern African market. “Vacuum excavation is a fairly new application for South Africa, which is slowly gaining traction,” explains McCallum. “It’s certainly a safer way of exposing utilities, like A popular option for smaller works is the HammerHead PortaBurst PB30 Gen 2 unit, designed for replacing 50 mm to 150 mm lateral pipes
high-voltage cabling, in preparing for trenchless applications.” Radar To ensure precision drilling, Ditch Witch also supplies ground-penetration radar systems via group entity Subsite Electronics. The latest offering is the 2550GR unit, which is designed to locate metallic and non-metallic pipes and cables at depths of up to 6 m, depending on soil conditions and antenna selection. Other applications include void and sinkhole detection, concrete detection, as well as the location of underground storage tanks. “In urban environments, trenchless technology is one of the best solutions for new as well as refurbishment projects in fields that include electrification, gas, fuel, water and sanitation. These are all areas where Ditch Witch machines have played a role worldwide on small- and largescale projects. That proven track record is now opening up new business opportunities for contractors within Southern Africa as private and public clients recognise the time and cost benefits,” McCallum concludes.
S E P T/ OCT 2018
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Laboratories & Equipment
Monitoring done right Online monitoring is a key piece of the technology puzzle, and vital to providing process transparency. Hach’s extended range of water analysers allows users to make informed decisions based on continuous data.
T
he quality of distributed water is of paramount importance, as it concerns human health. Operators are facing numerous regulations set against the practical limitations of their treatment facilities, and must satisfy disinfection requirements by using either chlorination or chloramination with minimal DBPs (disinfection byproducts). Online monitoring of multiple critical parameters is now possible for both processes, by means of a single, stand-alone water analyser from Hach’s EZ Series. Connecting critical process parameters Disinfection by chlorine is known to introduce a number of side reactions with organic and inorganic species. These reactions not only reduce the availability of chlorine but also produce several DBPs. Chloramination was introduced as an alternative method of disinfection, and involves the addition of ammonia before or after the addition of chlorine to produce primarily monochloramine (NH2Cl). The weight ratio of free chlorine to ammonia directly affects the type of chloramine formed, which can’t be controlled by the measurement of free chlorine or even free ammonia alone. The risk of over- or underfeeding chlorine in chloramination in this case is not far-fetched. Combining multiple critical parameters in one single platform gives the following options: •T o measure total and free chlorine levels, the analyser runs a double analysis cycle based on the established DPD (N,Ndiethyl-p-phenylenediamine) colorimetric
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method. Chloramine can then indirectly be estimated by calculation. • To measure monochloramine directly, the analyser runs a direct measurement by Berthelot. Free and total chlorine can then be determined in a separate colorimetric analysis cycle. Automated, online colorimetry Drinking water quality criteria often require the analysis of a large set of physico-chemical and biological parameters conducted by an in-house laboratory of the local water authority or external certified laboratories. The continuous, online monitoring of a set of target parameters can be an added value to operations to reduce lab workload or, in terms of process control, provide more real-time insight on critical points in the production plant. The EZ 1000 Series has been designed to monitor 10 essential water-quality indices, which are related to not only taste and appearance but also safety and disinfection. Generating up to six readings an hour for most parameters, the EZ 1000 Series provides almost real-time results on current process conditions. The built-in panel PC assures full integration and communication with industrial production sites and corporate networks. The EZ Series of online colorimetric analysers has already served in countless industrial, municipal and process water
applications. The flexible analyser mainframe allows a perfect online duplicate of most standard/laboratory wet-chemical methods, with outstanding precision and accuracy. At the heart of the colorimeter is a compact photometer assembly developed especially for the EZ Series. The consumption of reagents is reduced by low-volume analysis, yet high sensitivity is assured by a long optical path length. An external multiplexing unit makes it possible to monitor up to eight streams sequentially, reducing the cost per sampling point. The compact mainframe, packed with a robust architecture and high-quality components, requires little maintenance and inspection. Smart features such as automatic calibration/validation and cleaning are embedded in the controller software and minimise operator intervention. Automatic internal (or external) dilution is another possibility, with the software monitoring the result output and adjusting the measuring range if necessary to compensate for wide variations on a parameter. “At Hach, we are convinced that an analyser’s analytical performance should go hand in hand with trouble-free operation, minimal maintenance and easy data exchange,” says Robert Bollea, sales and marketing manager: subSaharan Africa, Hach.
www.hach.com
Setting a new milestone The world is constantly changing in the digital era, and the Tintometer family is changing with it.
H
Lovibond® Water Testing Tintometer® Group
Water Analysis made easy Lovibond® – The Original
eadquartered in Dortmund, Germany, the 130-year-old Tintometer group is reflecting its adaptability and growth through its new website – www.lovibond.com. The new website embeds the Lovibond® products for water testing and colour measurement in the global environment as one the company’s enagaged market segments. “In water testing, we are experiencing an enormous increase in demand for our products – whether it be the purity of potable water in water-stressed areas of the world, the monitoring of industrial water, process water, wastewater or the water quality of the private pool,” says company founder Cay-Peter Voss. Maja C Voss, managing director, notes that the company has expanded significantly over the past few years, growing to represent more than 160 countries with more than 370 members of staff: “We deliver innovative solutions all over the world and our new website builds on this with its various additional digital opportunities.” A new innovation The new website represents water testing and colour measurement on one webpage, providing clients with easy access to the reliable and high-quality solutions Tintometer is known for. With the click of a mouse, users can find anything from a suitable photometer to control pool water, to applying electronic colour measurement for petroleum oils, pharmaceuticals or waxes – including all technical data, reagents, accessories, downloads and safety data sheets. A product finder simplifies the search for a suitable instrument, and a download area, diverse search functions, a storage function and significantly more information are all offered with latest design. The various language versions are continually updated to ensure that customers and stakeholders across the globe are fully informed. “The new homepage marks a digital milestone and the beginning of a comprehensive development for our company,” Maja stresses. “We are well positioned and prepared for the global and changing challenges of the market.”
Optic a Techn l DO ology
One Stop Shop for Water Analysis Integrated Lovibond® solution for all routine measurements ■
Complete solutions for Waste and Drinking Water and various industrial applications
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Easy-to-use instruments, rapid results - yet resolutely accurate
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Photometric Analysis - up to 70 Parameters including Ammonia, COD, Nitrate, Nitrite, Nitrogen, Phosphate (reagents supplied)
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Photometer with Bluetooth® data transmittance to Lovibond® AquaLX® App
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QUALITY Made in GERMANY
brighter
quantification High-quality and easy-to-use Spectrophotometers, Reflectometers, and Test Strips and Kits for undisputed accuracy of your quantitative results
For further information please contact: Tel: 08600 63725 labsupply@merckgroup.com www.merckmillipore.com
Laboratories & Equipment
Water is essential to sustain all life on earth, and yet it is highly polluted. In order to ensure sustainable water resources, serious precautionary measures must be followed.
T
he basic and most reliable solution is spectrophotometric measurements, based on the Lambert-Beer law, which states that the concentration of an analyte is directly proportional to the amount of light absorbed, or inversely proportional to the logarithm of the transmitted light. The beam of light passes through a cell containing a colour solution, which decreases the light intesity, and the relation between the colour of the measurement solution and the light intensity determines concentration. Spectrophotometers alone are not enough to determine concentration parameters. Several preparations and practices are required prior to measurement. The simplest is a calibration graph where the relation between concentration and absorbance is shown. Over the past years, spectrophotometric methods have been reviewed and developed to ensure advantages for the users. The greatest development in this measurement is the commercially available ready-to-use test kit. Spectroquant® Prove spectrophotometers Whether analysing wastewater, drinking water or process water, the three most important requirements of a spectrophotometer are simplicity, security and durability. Merck has developed a new class of spectrophotometers that perfectly unites all these features. Intuitive, innovative and preprogrammed for the broadest range of test kits, Merck’s Spectroquant Prove makes water analysis smoother than ever. The Spectroquant system offers more than 170 different competent solutions – whether for testing drinking water, surface water, process water, municipal or industrial wastewater, beverages or performing disinfection control. The system comprises an entire series of test kits, photometers and all the
What if each drop was compliant? Let’s create confidence… together necessary accessories for customer-oriented sample pretreatment. It also offers the necessary support when it comes to comprehensive analytical quality assurance (AQA), guaranteeing the GLP-compliant documentation of measurement results for reliable and secure internal quality control (IQC) operations. The scope of parameters is finely tuned to the requirements of clients’ everyday operations and is constantly being expanded. Stringent controls of Merck’s raw materials, effective in-process controls and documented final controls ensure consistently high quality. Ready-to-use test kits Spectroquant® ready-to-use test kits comply with international norms and standards, using the same method principles in normative methods and colour reactions. This feature assures reliability and quality on a universal basis. Advantages for users include less toxic waste, handling steps ensuring fewer errors, and package inserts that include detailed information about the analysis – e.g.
A glance at the advantages of Spectroquant® •R apid and simple operation via the barcode system • Selection between cell and reagent tests • Validated and standard-compliant analysis methods • LIMS connect • Easy cleaning of the cell compartment
method determinations and influences of foreign substances. Ready-to-use reagents eliminate timeconsuming and cost-increasing steps. The addition of auxiliary substances and reagents are stabilised, interferences that may occur during analysis are precluded, and pH ranges of tests are increased. Each method is controlled and quality checked by repeated measurements using standard samples in Merck ISO 17025-certified laboratories. Test kits are validated, and results are shared on the analysis and quality certificates. Quality assurance Today, quality assurance is a decisive factor in water and wastewater analysis – results must be reliable and accurate. Merck ensures perfect AQA thanks to certified standards, GLP-compliant documentation and tools, and has a broad range of USEPA-approved/equivalent photometric Spectroquant methods. Only by ensuring start-to-finish quality assurance measures are findings considered secure, reproducible, and recognised analytical results. Rely on accurate measurement results with Spectroquant tests. S E P T/ OCT 2018
27
Demand Driven Distribution
delivers perfect pressure to your entire network
Intelligent pressure management solution available as an upgrade to your new or existing booster system
www.grundfos.com info_za@grundfos.com
Trademarks displayed in this material, including but not limited to Grundfos, the Grundfos logo and “be think innovate� are registered trademarks owned by The Grundfos Group. All rights reserved. Š 2018 Grundfos Holding A/S, all rights reserved.
Grundfos
The power of demand-driven distribution
Water Management
In the drive towards higher efficiencies and water conservation, Jonathan Kuppan, product specialist: iSOLUTIONS, Grundfos, tells us how demand-driven distribution holds the key. What are the most common challenges in water distribution systems and how can these be addressed? JK Amid a growing global population and increased urbanisation, we face unprecedented demands for both energy and water. We struggle with the challenges of water scarcity, high leakage rates, high maintenance costs and, of course, high energy costs in our distribution systems. According to one study, 45 million m3 of drinking water is lost daily through water leakage in the distribution networks – enough to serve nearly 200 million people. The majority of distribution systems run at high pressures to ensure that delivery pressures at the point of consumption are satisfactory. However, this often leads to pipe bursts and leakages, many of which are never reported or fixed. Adding to the energy crisis, pumps account for 10% of the world’s total electrical energy consumption, and up to 90% of them are inefficient. Saving energy means saving water and both add up to a healthier environment and bottom line. Currently, these challenges are addressed through pressure management systems, pipeline and asset management systems, and active leakage control. But
Figure 2 DDD system example
Figure 1 Friction loss vs flow
Low flow = low friction loss High flow = high fiction loss
there is another way of reducing costs and increasing efficiency – demand-driven distribution (DDD).
How does Grundfos’ DDD system overcome these challenges? When we examine the relationship between flow and friction loss, we conclude that flow is directly proportional to friction loss. This relationship is the basis for the DDD concept. In the race towards higher efficiencies and water conservation, DDD offers a smart solution for smart cities. DDD is designed to optimise a complete distribution system autonomously. The system has remote wireless sensors that are placed in critical points of the distribution system, sending pressure measurements to the pumping station. Installed in the pump station, we have a pump system equipped with variable-speed drives and the brain of the system, the
Grundfos CU 354 DDD controller. The DDD controller receives the data and, over a run-in period, creates a model for the network. With this model, the DDD system can typically keep a lower average pressure at critical points and reduce overall energy consumption. Some of the benefits of the DDD system include: • lower operating cost (due to lower average pressure) • lower leakage rate in the network • fewer pipe breaks • more stable supply to end users • less manual optimisation of network. There are, however, a few factors to be mindful of. The DDD system will not work in networks with water towers or those supplied from more than one pressure station, and there must be a stable water supply to the pump station. Networks with high pressure losses in the system at high flows, or where the pressure is fluctuating at the critical point, will benefit from DDD installation.
Can you provide an example of a successful DDD installation? We successfully implemented DDD at the Ploieşti Nord Gãgeni water supply zone in Romania – one of Bucharest’s four water supply zones with over 230 000 inhabitants. Although
Jonathan Kuppan Product Specialist: iSOLUTIONS, Grundfos
Ploieşti Municipality was already operating with a reduced nighttime pressure, the non-revenue water losses were reduced by a further 6.6% (±146 000 m3/year) and specific energy was reduced by a further 7.4% (±48 000 kWh/ year). With these savings, costs were recovered within one year. Read the full case study here: grundfos.com/cases/find-case/ ddd-ploesti.
What differentiates Grundfos from other solution providers and why is automation becoming increasingly essential for control systems? The emergence of Industry 4.0 and the internet of things presents new and efficient ways to monitor and control equipment. Grundfos has embraced this new culture to provide true value engineering. Grundfos iSOLUTIONS harnesses over 70 years of expertise to bring a new era of intelligence to pump systems and water technology, with solutions that look beyond individual components and optimise the entire system. Grundfos has become worldrenowned for quality, efficiency and smart control technology. It always starts with a close dialogue with our customers to define the scope of the challenges and the criteria of success. In this way, we are able to deliver a solution that effectively meets their individual challenges. We combine this with expertise we have gained over decades to provide the most efficient, reliable and cost-effective solution. This is the Grundfos iSOLUTIONS way. S E P T/O CT 2018
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Water Management
What WC/WDM can achieve for your WSA ** This paper is the second in a series of five articles by Derek Hazelton on WC/WDM. The first paper, titled ‘The current water crisis and WC/ WDM’, appeared in the July/August 2018 issue of Water&Sanitation Africa (Vol. 13 No. 4).
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he first step involves evaluating the current situation, using very simple water volume and money balances. The second step involves setting up the same water and money balances, using a sound estimate of the minimum economically achievable system input volume (SIV). This SIV will be made up of the water delivered to customers, assuming an acceptable level of non-recovered revenue (NRR) is achieved, and the non-revenue water (NRW) in the distribution system, assuming it is well managed. Comparing the results of steps 1 and 2 will reveal the water savings, and the financial gains, of implementing the WC/WDM project. Measuring the current situation In the first article on WC/WDM**, a number of variations of the IWA water volume balance were presented. To obtain a clear overall picture of a WSA’s current situation, a simplified adaptation of the modified IWA water volume balance should be prepared. Concurrently, an equivalent water money balance should be prepared. Figures 1 and 2 represent the water volume and money balances, respectively. Purchased bulk potable water
Selfproduced bulk potable water
Total system input volume (SIV)
Water services managers in many water services authorities (WSAs) find it difficult to motivate for the implementation of an integrated turnaround water conservation and water demand management (WC/WDM) project because they are unable to demonstrate to their municipal council and top management the water savings, as well as the financial and other gains. This article explains how to overcome these challenges. By Derek G Hazelton
If a WSA purchases bulk potable and/or bulk raw water, it can use the supply invoices to measure all these portions of the SIV. If there is any additional SIV, it is likely to be sourced from groundwater. Each associated borehole pump should have a water meter installed shortly after its delivery point to measure the water abstracted from each borehole. These meters will then measure the remaining portions of the SIV. If no meters are fitted, the water abstracted from the boreholes can be estimated from the pump performance details combined with either their hours of operation or the quantity of electricity or fuel used to power them. After calculating the total SIV, the corresponding SIV cost figures should be calculated, as indicated in Figure 2. As shown in Figures 1 and 2, by combining the SIV and SIV cost figures with the WSA’s subsidy allocations, the retail customer water billing system figures and the resultant recovered revenue, the current NRW volume and the gross surplus money available to operate, monitor and maintain the WSA’s water supply system can be calculated. While examining the WSA’s retail customer billing, free basic water and payment records
Volume charged-for deliveries + Managed free basic water
Paid-for sales + Free basic Non-paidfor sales
Non-revenue water = Total system input volume (Managed free basic water + Charged-for deliveries)
Figure 1 Overall picture of a WSA’s water volume balance
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Derek G Hazelton, Pr Eng., FWISA, founder and manager of TSE Water Services
Cost of purchased bulk potable water Variable cost of selfproduced bulk potable water
to draw up the water delivered, billed and recovered revenue figures for Figures 1 and 2, it is recommended to record the water deliveries to non-domestic consumers separately from the domestic, because the former will be used again, without altering them, to estimate the results of implementing WC/WDM. The number of non-domestic customers should also be noted. Estimating the results of implementing WC/WDM The approach To estimate the outcome of implementing WC/WDM, it is necessary to estimate the minimum economically achievable SIV. The SIV is made up of two components: • the customers’ true water demand, assuming cost recovery is well managed • the total losses that will occur in the water distribution system, assuming it is well managed. The customers’ true water demand is made up of two categories of customers: domestic customers and non-domestic customers. On average, domestic customers reflect about 90% of the demand. Because this demand is the higher and more difficult one to estimate,
Cost of total system input volume (SIV)
ES grant allocation + any other subsidies
Actual recovered revenue
Resultant gross surplus Figure 2 Overall picture of a WSA’s water money balance
Water Management the author of this article has estimated the water demand for each of the approximately 20 000 sub and main places in South Africa using the results of the 2011 census. Once the domestic water demand has been estimated, the WSA’s tariffs are used to calculate the potential revenue from this demand. WSAs are expected to use their billing system records to estimate the demand of, and potential revenue from, their nondomestic customers. Once both demands have been estimated, the total losses that will occur in the water distribution system, assuming it is well managed, are estimated. Finally, once all these variables have been estimated, new water volume and money balances are drawn up, as represented in Figures 3 and 4, respectively. These figures reflect the outcomes of implementing WC/ WDM and, therefore, represent the targets that ought to be striven for. In Figure 3, the resultant total system input volume is qualified by adding ‘acceptable?’. This is because first-level WC/WDM, as implemented by a WSA, does not normally try to reduce the water usage by rich paying customers and the estimated water demand reflects this practice. However, if there is a water shortage in the area, it will be necessary to discuss this situation with these high-usage customers and decide how their unacceptably high demand is to be reduced or managed. In Figure 4, the cell containing the resultant achievable gross surplus through implementing WC/WDM is shaded in dark
blue rather than TABLE 1 Assumptions for estimating the domestic water demands light blue. This is Average annual demands per Demand Total demands components because this figure day (based on CSIR Red Book Dry san. Wet san. table 9.11) reflects the results ℓ/cap.day of implementing Basic 35 35 35 WC/WDM only, but it assumes that Add: Yard connection dr y sanitation 25 60 60 all costs, tariffs, and budgeted ES Waterborne sanitation 50 110 grant allocations Household income per annum: and any other =<9 600 0 60 110 subsidisation >9 600 to 38 200 20 80 130 remain unaltered. In practice, if >38 200 to 76 400 30 110 160 the water supply >76 400 to 153 800 50 160 210 services operating, >153 800 to 307 600 90 250 300 monitoring and >307 600 150 400 450 maintenance Hostels per resident 80 130 budget was previously grossly This information was then integrated into a inadequate, it is likely that implementing single spreadsheet, to build up a rational set WC/WDM on its own will not increase the of domestic water demands. These demands available budget sufficiently to enable the were based on the assumptions indicated WSA to maintain its reduced NRW and imin Table 1. proved cost recovery, without the ongoing The Table 1 assumptions are only valid injection of special external funding. If this is if all delivered water, above the free basic the case, a higher gross surplus will have to allowance, is billed, and the non-recovered be generated by improved budgeting and/ revenue is kept to a minimum. These domesor more efficient management techniques tic water demands are a fundamental part will have to be introduced. of estimating the gains that can be achieved The next few sections of this article explain, from implementing WC/WDM. in more detail, how the domestic water demand and the water distribution losses are estimated and used to develop the target Adjusting the domestic water demand water volume and money balances, depicted from 2011 to the present The estimated water demand figures relate in Figures 3 and 4. to 2011, when the last census was carried Estimated out. These figures must be updated to allow True domestic Resultant volume total for the increases in population and in the water demand Resultant paid-for charged for: (acceptable?) number households with improved water The true domestic demand is sales + Managed free metered or system input basic water supplies and/or flush toilets. part of the estimated water metered and volume controlled volume presented in the (= True deliveries + The non-domestic water demand second column of Figure 3. demand + Managed free NRW) For non-domestic water, the volumes and To estimate this demand, the basic water Maximum acceptable following 2011 census results invoiced amounts abstracted from the non-paid-for sales WSA’s billing system are used without for each of the sub and main Estimated maximum acceptable total alteration. places in South Africa were real and apparent water losses = obtained from StatsSA: Resultant non-revenue water Estimating the total losses associated • area, population and Figure 3 Water volume balance after implementing WC/WDM In a well-managed water distribution sysnumber of households tem, apart from managed free basic water, • h ousehold access to ES grant allocation + Cost of there are no authorised unbilled deliveries. piped water any other subsidies purchased bulk As a result, the non-revenue water and the • household water source potable water Cost of total total water losses are equal. • household access to (acceptable?) With respect to estimating an acceptable toilet facilities system input Variable cost of volume (SIV) level of NRW, WRC report no. 521/1/98 • household income Estimated achievable self-produced contains a simple method of doing this. category. recovered bulk potable water
revenue
Resultant achievable gross surplus through implementing WC/WDM
Figure 4 Water money balance after implementing WC/WDM
TABLE 2 Assumed average number of persons served per connection for different levels of service Per yard or house connect
4
Per public standpipe connection
80
Per non-family-hostel connection
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Water Management TABLE 3 Comparison: Beaufort West LM before and after WC/WDM implementation The method is shown in Figure 5. Current WC/WDM Difference % KPIs (Note: all the KPIs Although the equation relates the demand targets have improved) Change non-revenues to the number of components connections and the water delivered Water volumes kℓ/annum per connection, it needs to be noted SIV 3 382 954 2 955 896 -427 058 -12,6 that the results take into account Total managed deliveries the water losses from all sources in a 1 545 675 2 418 437 872 762 56,5 well-managed system. This method NRW % 54,31 18,18 -36,13 -66,5 of calculating the maximum acceptFBW + paid for sales 1 414 293 2 297 515 883 223 62,4 able level of non-revenue water is the Non-recovered revenue 131 382 120 922 -10 461 -8,0 second fundamental part of estimatNon-recovered revenue % 8,5 5,0 -3,5 -41,2 ing the gains that can be achieved from implementing WC/WDM. The Water money R/annum true water demand estimated in the Cost of SIV 5 808 133 5 422 608 -385 525 -6,6 previous subsections, plus this level Total subsidies + recovered revenue 26 133 367 36 284 637 10 151 270 38,8 of non-revenue water, is equal to the Gross surplus 20 325 234 30 862 029 10 536 795 51,8 resultant total (acceptable?) SIV in the first column of Figure 3. G surplus R/kℓ of target 8,40 12,76 4,36 51,8 managed deliveries When estimating the acceptable level of NRW for the estimated + Change = increase - Change = decrease domestic demand, there is one small challenge with respect to using the StatsSA refers to the number of customer metering less the bills not paid. As estimated in the figures uncritically. That is, if one assumes units. As a result, even for yard and house first article on WC/WDM, in a well-managed the number of households equals the numconnections, the number of connections system, at least 95% of the total money ber of connections, the number will be too is normally fewer than the number of billed should be recovered. high because, with respect to public standhouseholds. To overcome this challenge, in If the WSA only allocates free basic water pipes, several households will be using each estimating the average domestic demand to its indigent customers, calculate the total connection and with respect to non-family per connection or access/delivery point, the money billed assuming no free basic water is hostel dwellers, a large number of people assumptions listed in Table 2 are used. delivered. Then find out how many indigent will be using each connection. Even with With respect to the non-domestic customers receive free basic water and respect to yard and house connections, the customers, the number of customers should calculate the money forfeited by the WSA as StatsSA definition of a household is different be noted, so that the average demand a result of these free deliveries. from WSAs’ loose definition, which really from these customer connections can be The total money billed for non-domestic calculated. The acceptable water delivered is taken from the WSA’s non-revenue water for the billing records. non-domestic connections is then calculated in exactly Beaufort West the same way as for the An evaluation was done for the Beaufort domestic connections. West LM WSA, which has a high level of NRW. Table 3 shows the results of the Estimating achievable evaluation. For Beaufort West, all KPIs would recovered revenue improve by implementing an integrated The achievable recovered WC/WDM project. revenue is simply the total For a full list of references, please contact the money billed from supplyFIGURE 5 Equation for estimating acceptable NRW volumes author at tsewater@icon.co.za. ing the true water demand
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Treatment
Landmark plant for Umgeni Water The 55 MLD treatment plant in iLembe has been handed over to Umgeni Water
A new 55 MLD potable water treatment plant will supply thousands of KwaZulu-Natal residents with clean drinking water.
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art of the Lower Thukela Bulk Water Supply Scheme (LTBWSS), the new bulk water treatment plant, constructed at a cost of R1.4 billion and funded by Umgeni Water and the Department of Water and Sanitation, will eventually supply approximately 340 000 people in the iLembe district with potable water, from inland of Mandini to Ballito in the south. This will be the first time many of these people receive a reliable supply of safe drinking water. In what is one of the largest municipal potable water treatment plants undertaken by Veolia South Africa, Veolia was responsible for supplying the required mechanical and electrical components for the treatment plant as well as for the customised abstraction works that will pump water from the river. “The remote location of the construction site required careful planning and logistical accuracy among each of the project stakeholders,” explains Pierre Michallet, senior project manager, Veolia Water Technologies South Africa. Veolia and its EPCM partners, as well as the primary stakeholders of the project, worked in close collaboration throughout the project to ensure successful execution and delivery. The treatment process Raw water is abstracted from the uThukela River through a boulder and gravel traps system that prevents large matter
This R1.4 billion design and build project is one of the largest municipal potable water treatment plants undertaken by Veolia South Africa
from being deposited into the water treatment works. The stream is screened as it is split into four canals designed to allow finer sediments and sand particles to settle. The flow is further pumped from the low lift pump station up to the beginning of the water treatment, the hydrocyclone. Additional filtering for sediment, grit, organic matter and heavy metals then takes place via gravity using clariflocculators, the Pulsator® pulsed sludge blanket clarifier and sand filtration. Underflow sludge accumulated across the treatment processes is dewatered through decanter centrifuges. As part of the CPG proposal, Veolia was responsible for fostering and developing relevant professional and technical skills among the region’s communities that can be utilised in the operation and maintenance of the water plant. A coordinated recruitment plan was used to identify locally trained engineers, mechanical and electrical
The plant is designed to supply roughly 340 000 people from inland of Mandini to Ballito
fitters, boilermakers, and other vocations that can be used in the plant’s operation. Veolia worked with Umgeni Water’s operations teams during the handover period in order to provide a seamless delivery of the plant at the end of July 2017. Provision has been made to scale the plant’s potable water production capacity from 55 MLD up to 110 MLD, should it be required in the future. S E P T/ OCT 2018
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WA T E R I S
L I F E
Never before has water safety and use been more impor tant than now. With South Africa recently having suffered a drought that threatened to collapse the economy in the Western Cape, as well as the ongoing mistreatment of the countr y’s water resources – including the discharge of raw sewerage into some of our main dams and rivers, which also threatens the countr y’s Blue Drop status, it is imperative that private sector also star ts playing a role in the value chain. These issues could fur ther perpetuate to our neighbouring countries. Vovani Water Products (P ty) Ltd provides safe, reliable and technologically advance products used in the manufacturing of water treatment plants for various industries in the sub-Saharan Africa (SSA) region. We offer a number of solutions, including desalination, brackish water treatment, sur face water purification and much more. Only the highest quality and standards are acceptable, with all deals grounded by professional ser vice. When viewing the water supply chain, it is also impor tant to consider how implementing high-quality, fit-for-purpose products, could translate into significant cost and time savings for your company. Primarily, Vovani looks at the design characteristics of each product and how this can be used in your supply chain, aiming to be the preferred supplier of specialized water treatment components and hydro-mechanical water use equipment in the SSA market. Vovani should be considered as the first contact when customers search for these products. Vovani’s products are trusted by industr y and, as such, was recently used in a waste-to-water treatment plant at a large office complex in Cape Town. Our product range is renowned and includes solutions and systems for technical water utilisation. We supply top global brands, including Aqua Solutions, Fedco, LG Chem, Muhr, Piedmont, ROPV and SUEZ.
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Automation & IoT
Due to the critical drought conditions in the Western Cape, the Department of Water and Sanitation now requires that all agricultural abstractions from the Berg River be metered.
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he Berg River is a key source of water for Cape Town, surrounding towns and agricultural enterprises. Appointed by the Lower Berg Irrigation Board, Bosch Munitech, part of Bosch Holdings, has undertaken the design and implementation of a compliance metering and monitoring system on all irrigation abstraction points along the river. A first for South Africa An important aspect of the project was that all flow meter readings had to be readily accessible in a database for online access of consumption data of each water meter connected to the system. “To transfer measurement data from 135 abstraction points along the river to a central database, an alternative to the traditional GSM approach was used. The team deployed a purpose-built internet of things (IoT) communications platform and Liquid Fibre web-based data management portal, which we believe is the first application of its type in South Africa,” explains Iaan de Beer of Bosch Munitech. “The Liquid Fibre portal allows users to conveniently view and export flow meter
Harnessing IoT for drought management
data online from PCs and smart mobile devices. The webbased application overcomes the usual challenges of high installation costs, unreliability of signal coverage and SIM card management.” Krohne Waterflux electromagnetic flow meters, which meet stringent potable water standards, were proposed and installed at the majority of abstraction points between Sonquasdrift and Velddrift. These lowmaintenance water meters are designed for bidirectional flow measurement over a wide dynamic range. Waterflux water meters have a rectangular sensor that enables a stable measurement, even at low and uneven flow rates. They offer high accuracy of less than 0.5% across the measurement range. The optimised flow profile of this series enables installation anywhere, without the need for straight inlet or outlet runs. These meters are also suitable for burial installation and immersion in flooded chambers.
Bosch Munitech has undertaken the design and implementation of a compliance metering and monitoring system on all irrigation abstraction points along the Berg River
Another first was the introduction of the highly accurate Nivusonic transit time flow meters. The ease of installation of these meters offers substantial savings over the standard mechanical installation cost associated with inline flow meters on largediameter pipelines. Bosch Munitech works closely with municipalities throughout the country to provide efficient service delivery solutions to urban and rural communities. S E P T/ OCT 2018
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Automation & IoT
Changing the infrastructure space
Industry 4.0 and the internet of things (IoT) are set to fundamentally alter the way we live, work and relate to each other. While the water and wastewater industries are realigning themselves with IoT, to improve efficiencies and reliability of service, this comes with its own unique requirements. By Dr George Gerber*
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ociety is on the brink of the Fourth Industrial Revolution, which is building on a digital revolution that is merging physical, biological and digital systems. It promises to raise income levels and improve the quality of life on a global scale, but also has the potential to increase inequality in the labour markets, if not carefully managed. Big data analytics will play an important role within this revolution, enabling
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businesses and government to provide improved services to more consumers at a lower cost. It offers two main benefits, namely speed and efficiency, allowing business to process far greater volumes of data and decisions to be made in real time. There are two important pillars that support big data analytics: IoT and artificial intelligence (AI). A main feature of IoT is that it can generate and transfer large amounts of data from the physical world to data centres in the cloud. AI, on the other hand, is used to uncover the hidden patterns, correlations and insights in the data. Globally, the number of devices connected to an IoT platform is expected to increase significantly, from 400 million in 2015 to 3 billion in 2020, as governments and industries begin to implement IoT and smart methods to solve region-specific challenges.
Infrastructure monitoring Infrastructure and economic growth are intricately intertwined. Infrastructure can increase productivity, create jobs and stimulate trade, while economic growth can increase investment in infrastructure. Infrastructure monitoring and management are crucial processes that ensure the value derived from our infrastructure is maximised. The emergence of IoT and other smart methods has transformed infrastructure condition monitoring and management globally. Condition monitoring can be done remotely and in real time, allowing substantial amounts of data to be collected at key locations and times. Furthermore, big data analytics, and soon AI, will automatically transform this data into information for decision-making. This is particularly relevant for South Africa. The 2017 SAICE Infrastructure Report Card showed the declining state of the countryâ&#x20AC;&#x2122;s infrastructure and identified three factors that have a critical impact on the condition
Automation & IoT
of infrastructure: the institutions that are tasked with their creation and maintenance, the skills within these institutions, and the availability and appropriate use of data and information to influence decisions. The regular collection and management of data forms the foundation for meaningful policy development and enables accountable, evidence-based decision-making. This is relevant across all areas of infrastructure, including the water, wastewater, stormwater and irrigation fields. Application examples The application areas of IoT in the water and wastewater fields are numerous, ranging from flood control to revenue optimisation. Water quality monitoring, for example, requires the measurement of critical water quality parameters such as microbial, physical and chemical properties, to identify deviations in parameters and provide early warning identification of hazards. IoT is well suited for these tasks and can be used to provide proactive warnings of pollution incidents in a reservoir or chlorine levels in a distribution system. This allows water service providers enough time to mitigate the impact before supply reaches consumers. Water meters can send measurements wirelessly to water service providers to help detect leaks early and improve consumption estimates. Consumers can also view a detailed time record of their consumption, which will assist them in reducing consumption.
Pump station and treatment plant control equipment can monitor key performance variables and relay this information to an IoT system. The operator can control various parts of the plant through a web service and the measurements can be visualised in a format the process operator is familiar with. Various operating scenarios can also be investigated through simulation of the network infrastructure. The GIS capabilities allow the condition of individual assets of the system to be interrogated on a map and their repair and maintenance activities scheduled in an efficient manner. In wastewater networks, level sensors can be installed at key locations and remotely send an alarm when the network is approaching an overflow event, allowing preventative action to be taken. The sensor data can be overlaid on a map to identify surcharging areas in the system. The operation of stormwater ponds in cities can be optimised by connecting them to a rainfall warning system. The ponds can deplete themselves before a rainfall event, increasing their storage capacity and attenuating downstream flood peaks. This minimises flood damage and prevents casualties. Urban rainwater harvesting systems can play a similar role in reducing stormwater flood peaks, by managing their content before and during a rainfall event. Boreholes are being upgraded with IoT capabilities, allowing water utilities to work with local borehole operators to ensure
Benefits of IoT and smart methods for infrastructure monitoring 1. Evidence-based decision-making using data records 2. Improved uptime and reduced service interruptions using maintenance-oriented sensors on physical equipment 3. Rapid response to accidents or incidents 4. Mobility for many aspects of civil service and commerce, as well as support business growth and broader access to government resources 5. Solving higher-level issues, such as managing real-time demand and energy costs 6. Improved civic engagement about planning processes and priorities, as well as the costs of vandalism
that boreholes are switched off during droughts. This gives boreholes time to recharge instead of pumping the aquifer dry. Subsurface drains in irrigation fields allow the ground water table to be controlled. The water table control system can be made to act proactively by connecting it to a rainfall weather warning system. Before the arrival of a storm, the water table can be lowered, increasing the subsurface storage capacity of the field and reducing surface water run-off. Crowdsourcing of incidents using apps or social media platforms can also be used as a data source to assist operators and maintenance personnel to respond quickly to new problems such as burst pipes or overflowing manholes. Implementation challenges When it comes to collecting data, quality is vital; however, data quality can sometimes be overlooked in the pursuit of collecting large volumes of data remotely. This can result in incorrect conclusions and misleading recommendations. Poor-quality data is commonly caused by a lack of meter cleaning, accidental or deliberate tampering with meter
Automation & IoT programming, poor scaling of the sensor readings, and biofouling and sedimentation of primary flow measuring structures, such as weirs and flumes. Another challenge is the incorrect selection of flow meter technology. The golden rule is to think of how the meter will be operated, maintained, whether it is accessible, and whether the conditions are appropriate for its operation. Incorrect installation of flow and level meters can also result in poor-quality data. Security risks One of the biggest challenges to IoT is that the growing dependence of economic and social systems on information technology has directly increased the risk of cyberattacks. The security requirements for an IoT system are influenced by numerous factors, including network configuration, the location and accessibility of the devices, the communication protocol used, the skill levels of the operators, as well as the number and type of devices.
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Several security steps can be taken to ensure that data is secured. These include both the encryption of data and communication, together with user authentication. It is important to change devices’ default usernames and passwords as soon as possible, as well as the default communication port number. Device verbosity should be minimised by limiting the amount of information output from the server and edge nodes. Edge nodes should support over-the-air updates to ensure that the device automatically gets the latest security patches. Additionally, devices should not have back doors for debugging purposes, as they can be
discovered and compromise the device and its data. IoT has unique requirements, most notably electronic, database, networking and security skill sets. However, it has the potential to generate large amounts of data, which AI will process to find correlations and make decisions. These decisions will feed back to the physical system to adapt to the prevailing conditions and improve operational efficiency. In this way, the Fourth Industrial Revolution promises to improve quality of life on a global scale.
*Dr George Gerber is the associate director of Uhambiso Consult.
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The first of its kind - a level switch that can handle any environment ... ... temperatures from -196 °C to +450 °C, pressure from -1 bar to +160 bar for all liquids The new patented drive of VEGASWING 66 as well as extremely temperature resistant materials, make it possible. • Point level switch and overfill protection device
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Sophisticated measurement solutions
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ince radar was developed and deployed during the Second World War, its use has expanded enormously. When it comes to level measurement, radar offers accuracy and efficiency. Radar level measurement systems can be very successfully utilised for assessing the filling level of liquids in tanks. Radar is exceptionally robust and can be used in any circumstance, weather or environmental conditions, as well as for nearly every temperature range and viscosity of measured medium. “Accurate, consistent measurement is essential. Radar technology delivers just that,” says Deon Rampathi, sales manager, Krohne. These systems continuously and impressively demonstrate their advantages against other techniques in a very wide variety of industrial applications. The major benefit is the contactless measurement principle, which is based on time-off light echo measurements in the free space above the filling medium, by using microwaves. This allows for reliable measurements under various practical conditions. Microwaves also easily propagate through dust and mist in the air – propagation speed is largely constant and independent of the air composition and parameters like pressure and temperature. A smarter solution As the world becomes ‘smarter’, solutions are becoming increasingly tech-savvy and automated. Smarter measurement enhances the safety, sustainability and efficiency of operations. This extends into more reliable and enhanced uptime as well as the extension of equipment service life. In response to this, Krohne has introduced the OPTIWAVE 7500, a powerful radar measurement tool geared towards hard-to-reach situations. “It’s a new generation of liquids measurement, with better measurement performance, enhanced software and an improved, more powerful signal processor,” says Rampathi. The OPTIWAVE 7500 has an 80 GHz FMCW radar-level transmitter for liquids in narrow tanks with internal obstructions. The flushmounted PEEK lens antenna means there is no tank intrusion. The measuring tool is also insensitive to deposits and has a small dead zone and beam angle with flange plate protection for corrosive media and a 112 mm antenna extension for long nozzles. Accuracy is ±2 mm and there is an extensive choice of process connections, with measuring distances up to 100 m in up to +1 500° C. For customers looking to keep their existing antennae, the OPTIWAVE 7500 retrofit option allows for an upgrade to the electronics without losing the hermetic seal on the tank. “As a world leader in the manufacture and supply of industrial process instrumentation, Krohne is focused on creating solutions for almost every application and understanding the need for smarter, more efficient systems,” says Rampathi.
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Me ters, Pipes, Pumps & Valves
A smart solution to leak detection A new study is proving that fibre-optic cables can be used successfully to identify leaks on water pipelines. By Danielle Petterson
O
ver the last 18 years, fibre-optic instrumentation has been developed to measure temperature and strain with an unprecedented resolution. It is possible to take continuous strain and temperature measurements along the length of a fibre-optic cable extending many kilometres. A study, funded by the Water Research Commission (WRC), is currently under way at the Department of Civil Engineering at the University of Pretoria (UP) to investigate the use of fibre-optic technology as a means of leak detection. How it works When shining a laser along a fibre-optic cable, back scatter is produced in areas of imperfection, making it possible to analyse the strain distribution along the length of the cable, explains UP’s Professor SW Jacobsz. Ground conditions in South Africa consist of mainly unsaturated soils.
In these conditions, significant strains can be detected in a fibre-optic cable buried in the ground due to leaks when the surrounding soil becomes saturated, resulting in a softening of the ground and a change in weight. The fibre-optic cable is able to detect this strain, providing an indication of a potential leak. The cable can be monitored at set intervals against a baseline reading to detect a sudden change in strain, which is typically indicative of a leak. These fibre-optic cables can be directly routed to a surveillance centre, or streamed via a radio or cell phone link, where it can be interrogated in a central location through a read-out unit. According to Jacobsz, the read-out unit is the expensive component in the system. Fibre-optic cable, however, is relatively cheap, amounting to roughly R10 to R20 per metre. It is also completely inert from the electrical disturbances that electric monitoring systems typically suffer from and sections can easily be replaced as needed. This technology is best suited for new pipelines as the fibre-optic cables can be easily buried with the pipe in the trench. However, Jacobsz says he is also investigating the suitability for retrofitting. While this is not practical in built-up urban areas, it may be suitable for large water mains that run through open areas, particularly with new trenching technology. “You can dig down fairly close to the existing pipe and lay the cable. If the soil below it becomes wet, you will detect movement associated with soil
settlement, resulting in strain on the cable,” explains Jacobsz. Trial study Together with master’s student Sebastian Jahnke, Jacobsz has conducted a trial installation at UP’s Experimental Farm in Hatfield. A short length of pipeline, fitted with artificial leak points, was installed together with a fibre-optic cable with strain sensors spaced roughly 1 m apart along the cable. This provides discrete measurements at set intervals, but Jacobsz hopes to take the study further to explore continuous reading along the cable. Two fibre-optic cables were installed with the pipe: a free-floating cable in the corner of the trench, and a cable fixed to the pipe. The results found that the cable placed in the trench provides more reliable results, as the cable fixed to the pipe is sensitive to pressure fluctuations within the pipe, which may cause difficulty in identifying potential leaks. Jacobsz says they initially thought they would detect a significant drop in temperature in the event of a leak. However, research found that while there is a small temperature drop, the strain change is far greater. “Strain is a much more sensitive parameter to monitor compared to temperature in unsaturated soils,” he says. The study has not yet explored the use of fibreoptics for leak detection in saturated soils, but Jacobsz believes temperature change may be the better indicator in such a scenario. Heavy, extended rains, however, do present a challenge, as they
result in wetting of the soil profile to a depth that affects the fibre-optic cable. However, strain will then be detected along an extended length of cable and will stabilise after the rainfall event. “With rainfall, you don’t see a continued deviation as you would with a leak. It is important to look at rainfall records when you interpret your data,” says Jacobsz. The trial installation is being monitored over the long term to assess seasonal fluctuations in strains. Jacobsz explains that there are temperature fluctuations over summer and winter, which do cause minor amounts of strain. These, however, appear to be gradual and cyclical in nature, unlike a leak, which would cause a sudden spike deviating from this pattern. The next steps Jacobsz is seeking funding for research to further the studies. This could involve installing and monitoring fibre-optic cables along active main water pipes and distribution networks. Rand Water, for example, has roughly 3 500 km of large water mains, many of which are not in urban environments and need to be maintained. He is also receiving assistance on the project from the Cambridge Centre for Smart Infrastructure and Construction in the UK, which has been using fibre-optic instrumentation for over 15 years to monitor ageing infrastructure in the UK. Jacobsz believes that the fibre-optic method offers several advantages over existing leak detection methods by providing a passive system for reporting leaks without the need to go out and search for them. “The application exists for this technology to be installed on all major distribution pipes and the WRC is looking into commercialising the technology,” he concludes. Early indications are that the proposed system will be successful in identifying leaks on pipelines, enabling early remedial action to be taken. S E P T/O CT 2018
41
Me ters, Pipes, Pumps & Valves
There are various pipe options available for use in bulk water pipelines. However, PVC-O shows clear benefits over its competitors.
T
he minimum required strength (MRS) of a polymer, determined in accordance with ISO 9080 (determination of the long-term hydrostatic strength of thermoplastic materials in pipe form), at 20° C and 50 years is used to
A case for PVC-O in bulk water pipelines determine the allowable design stress for a polymer in pipe form. This is an ISO protocol requirement applicable to all thermoplastic pipes. Determining the MRS The MRS is obtained from the CRRC (creep rupture regression curve) of the polymer, the unique ‘fingerprint’ of every polymer, by taking the rupture stress (MPa) at 438 000 hours (50 years) on the 20° C line. Graph 1 shows the 20° C CRRC for various polymers. It is important to note that PVC-O has five orientation classifications – 315, 355, 400, 450 and 500. The CRRC for PVC-U and PVC-M is precisely the same, but Sizabantu Pipe Systems’ PVC-O, TOM 500©, has an MRS of >50 MPa at 50 years.
Graph 1 Creep rupture regression curves at 20°C
42
SE PT /O CT 2018
A comparison of properties The mechanical properties matrix, in Diagram 1, compares the magnitude of five attributes of PVC-U, PVC-M and PVC-O. It is clear from this diagram that PVC-M shows a moderate increase in impact resistance compared to PVC-U, while PVC-O shows a substantial increase in impact resistance compared to PVC-M. In fact, all attributes are increased with PVC-O. A comparison of PVC-U, PVC-M and PVC-O attributes, relevant to their use in pressure pipelines (see Table 1 on page 44) shows the clear benefits of PVC-O. TOM 500’s allowable design stress is twice that of PVC-M. Historically, the market has been dominated by steel and DI (ductile iron) pipes, with some glass-reinforced polyester – each with its own unique set of problems engineers must understand and solve.
Me ters, pipes, Pumps & Valves
Diagram 1 Properties matrix of PVC-U, PVC-M and PVC-O
PVC-O PVC-M PVC-U
The substantial improvements in PVC-O’s polymer technology, material and processes have enabled significant increases in the attributes of the pipes. As a result, their application is extensive, such as bulk water trunk mains where large-diameter, high-pressure pipelines are required. PVC-O’s hydraulic capacity is also greatly improved due to the reduced rugosity (see Graph 2). Understanding surge magnitude Surge magnitude is essentially proportional to the initial flow velocity and the celerity of the pipe material. PVC-O’s celerity is low compared to other pipe materials – about one third that of DI. This enables the design engineer to use higher initial velocities, thereby increasing the pipeline’s capacity. It is important to note that the celerity of thermoplastic pipes varies with pressure rating.
Construction costs are essentially proportional to the mass of the pipe, taking into account expensive handling plants and the skills required to perform the jointing. Steel pipes require highly skilled, expensive coded welders for jointing, and skilled personnel for the lining and coating at the joint. PVC-O pipes do not require handling plant up to about 355 mm diameter pipes or skilled personnel for the spigot and socket jointing system. The result is that PVC-O
is significantly less costly to install, as shown in Graph 3. Corrosion and maintenance Corrosion relies on three elements: ferrous ions, moisture and oxygen. Because thermoplastics contain no ferrous ions, they cannot corrode. Pipelines that contain ferrous ions must be protected with corrosionresistant coating and lining material that adds weight and cost. And, once installed, they may require additional
Construction costs Steel and DI pipes are heavier than PVC-O, as shown in Table 2. Graph 2 Hydraulic capacity comparison S E P T/O CT 2018
43
Me ters, Pipes, Pumps & Valves TABLE 1 Various properties of PVC-U, PVC-M and PVC-O
protection by CP (cathodic protection), as any damage to the coating or lining will hasten corrosion of the pipeline. CP costs vary considerably depending on many factors including, inter alia, stray currents and soil resistivity – approximately less than 1 000 Ω/cm is considered extremely corrosive and greater than 10 000 Ω/cm is considered non-corrosive. CP capital cost estimates vary considerably from about 5% to 40% of the cost of the pipeline, although 25% is a generally accepted figure. Thereafter, maintenance costs throughout the pipeline’s service life must be paid including, inter alia, replacement of sacrificial anodes (usually magnesium or zinc), impressed current operation, vandalism repairs, and general operating costs. Much of the CP’s infrastructure is above ground and therefore vulnerable, particularly in remote areas. Lastly, all thermoplastic pipes must undergo a test for ‘effect of water quality of pipes intended for conveyance of water for human consumption’. In line with this, they must not constitute a toxic hazard, support microbial growth or give unpleasant taste, odour, cloudiness or discolouration to the water. The concentrates of substances, chemicals and biological agents leached from the materials must not exceed the WHO or EC Council Directive 98/83/EC maximum values. Because there is no deterioration of the thermoplastic pipe material, there is no contamination of the water conveyed by PVC-O.
Units
Property
966-1
966-2
16422
16 – 630
50 – 630
110 – 1 200
bar
4 – 20
6 – 25
12.5 – 25
MPa
25
25
50
Material classification
-
250
250
500
Ser vice coefficient (C)
-
2
1.4
1.4
Allowable design stress
MPa
12.5
18
36
Elastic modulus – shor t term
MPa
3 300
3 000
4 000
Elastic modulus – long term
MPa
1 500
1 400
1 800
Tensile strength – shor t term
MPa
52
48
75
Tensile strength – long term
MPa
26
26
55
Elongation at break
%
50
75
75
Poisson ratio
Pressure classes (PN) Minimum required strength
-
0.4
Coefficient of expansion
K
6 x 10
Absolute roughness (k)
mm
0.007
0.007
0.005
kg/m3
1.4 x 103
1.4 x 103
1.4 x 103
Density
-1
0.4 -5
6 x 10
0.4 -5
8 x 10-5
Graph 3 Average construction costs
TABLE 2 Masses of PN 16 pipes Diameter
DI
Steel
PVC-U
PVC-M
mm
kg/m
kg/m
kg/m
kg/m
kg/m
110
15.82
3.38
2.4
1.68
4.36
3.18
2.02
5.46
4.02
2.52
7.13
5.13
3.19
11.15
8.03
4.87
140
TOM500 PVC-O | SANS 16422
PVC-O
-
125
TOM 500 PVC-O
PVC-M
mm
SANS Outside diameters
PVC-U
160
23.82
200
32.18
27.7
PVC-O
6.05
225 250
42.55
34.6
17.51
12.57
7.40
315
54.00
41.3
27.85
20.05
11.77
355
66.91
45.4
35.58
25.60
14.79
400
80.18
52.0
43.26
32.57
18.82
450
95.27
58.6
39.97
23.87
500
110.91
65.1
29.41
630
146.55
84.8
46.72
700
184.00
91.5
800
226.73
105.0
75.46
Mine Water
A long-term solution
As Johannesburg’s acid mine drainage (AMD) problem continues to grow, a long-term solution is being sought to tackle the pollution and potentially supplement the region’s water supply.
E
stimates by Wits University’s School of Geosciences put the potential volume of AMD for the Witwatersrand Goldfield alone at 350 Mℓ/day, which equates to 10% of the potable water supplied daily by Rand Water to municipal authorities. This poses a serious threat to the Vaal River System. According to the Department of Water and Sanitation (DWS), if the salt loading on the Vaal River System caused by the discharge of AMD from mines and sewage effluent is not eliminated or suitably reduced, excessive dilution releases from the Vaal Dam will be required to achieve the resource water quality objectives in the Vaal Barrage and downstream. This will result in unusable surpluses developing in the Lower Vaal River, potentially externalising the cost of pollution to the Lower Orange River.
If the issue is not addressed, the DWS warns that the acceptable levels of water supply assurance may be threatened, increasing the risk of water restrictions that may have to be imposed on Vaal River water users. Short-term interventions The Trans-Caledon Tunnel Authority (TCTA) was appointed to undertake emergency works in the Eastern, Central and Western basins of the Witwatersrand goldfields to address the AMD problem back in 2011. The main objective was to stop decant in the Western Basin and prevent the breach of environmentally critical levels in the Central and Eastern basins. In February 2017, the Minister of Water and Sanitation inaugurated the Eastern Basin AMD plant, signalling the successful completion of the short-term Interventions. The TCTA is now moving to implement a long-term solution to the AMD problem. Long-term solution A feasibility study to address underground mine-water-induced salt loading of major river systems in the long term was initiated as far back as early 2012. Although the DWS launched the long-term solution back in 2016, Sibalo Dlamini, head: Projects, TCTA, reports that the procurement process is now under way for a professional service provider to implement a long-term solution. This solution will consist of treatment plants designed to treat AMD to either river or
ABOVE LEFT AMD Eastern Basin plant complete and in operation since September 2016 TOP Plant reactor tank in operation from June 2016 ABOVE Neutralised AMD discharged into the Blesbokspruit
potable standards, says Dlamini. Construction of the treatment plants is expected to begin in 2019, with the project estimated to cost about R11.8 billion. Dlamini explains that this forms part of R43.5 billion in funding, guaranteed by National Treasury, which the TCTA needs to implement both the AMD projects and the Lesotho Highlands Water Project, as they both form part of the Vaal River System and therefore fall under one funding strategy. The funding strategy calls for a R35.3 billion bond programme, as well R8 billion in loans, which the TCTA is going to go out into the market to raise. The TCTA is currently engaging with potential uptakers of the treated AMD, particularly big industrial users, which will inform the degrees to which the AMD is treated and the standards to be met. The DWS’s National Water and Sanitation Master Plan seeks to diversify South Africa’s water mix, and calls for 2% of South Africa’s water supply to come from treated AMD by 2040. It is envisaged that the long-term AMD solution will contribute to water supply to the Vaal River System. S E P T/O CT 2018
45
Mine Water
South Africa’s agricultural sector accounts for roughly 60% of water use, but the mindset around irrigation with perceived poor-quality water has been one of caution. With more pressure on its water resources, South Africa is now looking to develop guidelines for irrigation with mine water.
M
ore than 30 years of research has shown that mine water could very well be safe for agricultural use. The Department of Water and Sanitation (DWS) is now embarking on an initiative to understand mine water’s potential for irrigation and the requirements for sustainable and responsible irrigation with mine water. The project has been spurred on by devastating drought conditions currently gripping several parts of the country and forms part of government’s national long-term approach to acid mine drainage. The intent is to develop a guideline for irrigation with mine water based on the outcomes of the research, ultimately for national roll-out.
A game changer
in agriculture Anglo American Coal South Africa’s Mafube Colliery has been selected as the first trial site to determine the long-term sustainability of using mineimpacted water in agriculture. The coal producer is working alongside the DWS, Water Research Commission, University of Pretoria, Mine Water Coordinating Body, and Strategic Water Partnership Network on the landmark project. Trial site success The research project involves the establishment of two 30 ha trial sites – one on virgin land and the other on ground rehabilitated post mining. Crops are watered with saline water from the mine with a neutral pH, requiring no additional treatment before use. Saline-tolerant crops like wheat, maize, soya and ryegrass are to be planted on a rotational basis. The five-year project, which should run to 2021, has already had some success. The first crop – maize on virgin land – was irrigated with water from the Mafube pit and has since been harvested. The area yielded
14.5 t/ha, compared with 8 t/ ha from dry land crops. Stooling rye has been planted as the winter crop, which will be used as cattle fodder. “In a water-scarce country like ours, optimal use should be made of all available resources – mine water included,” says Ritva Muhlbauer, water manager, Anglo American Coal South Africa. “Mining activities in the Mpumalanga coalfields result in the production of large volumes of water that need to be carefully managed, both during a mine’s operational life and post closure.” In the future, Anglo American Coal South Africa will consider irrigation where the quality of the water is suitable as part of a closure strategy or where land has been rehabilitated and can be used for agricultural purposes with suitable mine water. “The Mafube Colliery project convincingly shows us that water from coal mines can be successfully used to irrigate maize and improve productivity by about 80%. Projects of this nature are multifaceted: they involve
Mine Water
joint public-private partnership, infrastructure development and enterprise creation. Through this effort, a second economy is formed that is capable of sustaining the livelihoods of the communities, once mines have ceased operations,” says Deputy Minister of Water and Sanitation Pamela Tshwete. A game changer for two industries If the project proves irrigation with mine water is viable, farmers would be able to plant crops year-round – not only during the rainy season – without having to abstract water from already pressured catchments. This could have major benefits for both the mining and agricultural sectors. While the quality of the mine water does play a role in the viability
of mine water irrigation on a larger scale, requirements in terms of appropriate limits and necessary treatment requirements (where needed) will be developed as part of the programme to ensure responsible use. “If we prove that irrigation with mine water is indeed sustainable, it would be considered a national asset rather than a liability, while increasing the profitability of farmland,” says Muhlbauer. All permissions from the Department of Mineral Resources and DWS are in place for the unique project that sees
government, industry and academia work together. The DWS is fully involved at both operational and governance levels, to advise the team on any regulatory issues that may emerge, both within the context of the project and later with its potential nationwide roll-out. Muhlbauer believes the practice is totally unique in that it would open up opportunities for rehabilitated mine land, thereby averting food shortages, particularly in times of drought, while promoting the creation of post-mining opportunities by enabling small- and large-scale commercial farming.
“The Mafube Colliery project convincingly shows us that water from coal mines can be successfully used to irrigate maize and improve productivity by about 80%.”
S E P T/ OCT 2018
47
A strong foundation for infrastructure success
Award-winning sanitation solution Rocla’s innovative Thuthukisa sanitation units, installed at the Amatole Municipality Sanitation Project based in Butterworth, Eastern Cape, were recognised at the recent 2018 Concrete Manufacturer’s Association (CMA) Awards.
R
Project Description ROCLA is South Africa’s leading manufacturer of pre-cast concrete products. Surpassing 100 years of product excellence, including pipes, culverts, manholes, poles, retaining walls, roadside furniture, sanitation and other related products within infrastructure development and related industries.
Visit us on www.rocla.co.za for our nationwide branches
ocla’s Thuthukisa sanitation units enable community members or SMMEs to manufacture concrete toilet units where they are needed. They are lightweight enough to easily be transported to their final site placement or can be manufactured right there where they will be erected. This eliminated the capital requirement usually associated with a manufacturing facility, no matter the size of the project. “Thuthukisa means ‘to share’, and it was based on this philosophy that our design team came up with the development of the sanitation unit that has the added benefit of enabling resulting waste material to be recycled into practical items for everyday use,” said Andre Labuschagne, product development manager, Rocla. The units are manufactured by casting one item on top of another in frameless single-use moulds of a similar size in a planar form. The product is left to cure, but new castings can continue to be made during this time at other locations, using the same tools. After the moulds have been stripped and cleaned, the waste can be recycled into useful items such as bean bags, pillows, blankets or duvet covers. This innovative approach led to Rocla winning the Engineering Excellence Product Innovation Exceeding 100 kg and Overall Winner for Engineering Excellence categories at the CMA awards. “It is a proud moment for Rocla when its engineering innovations are recognised by the CMA. The Thuthukisa sanitation units are not only unique through design, but also in the role they play in skills transfer and upliftment for the communities where they are installed,” said Labuschagne.
48
S E P T/ OC T 2018
WISA
Long-standing WISA member professor Kevin Wall has been awarded the NSTF Lifetime Award.
A lifetime of achievement
C
ivil engineer and town planner professor Kevin Wall has throughout his career endeavoured to improve service delivery. He has worked on an extensive list of projects at all government levels, written and presented many papers and supervised postgraduate students, in the process receiving numerous awards. For example, he is one of only six living recipients of a SAICE Gold Medal. Wall’s output has influenced government thinking and planning. As a result of his building the case for improved infrastructure asset management, he was invited to draft the National Infrastructure Maintenance Strategy, and led the team that formulated the National Water Services Infrastructure Asset Management Strategy. Also, he has been both research team leader and co-author of the three SAICE national infrastructure condition report cards (2006, 2011 and 2017). “A pipe being laid in the ground or a section of road being completed does not constitute delivery of any kind of service,” says Wall. “Service delivery is water coming out of that pipe, clean fresh and pure, at the right pressure, 24/7 for the next 50 years.” For that to happen, the infrastructure has to be operated and maintained properly. “It’s difficult to express the importance of infrastructure maintenance to a lay person, as well as the consequences of not conducting maintenance. It also doesn’t help to give a difficult explanation,” he says. Redefining development These achievements come from dedication to service delivery. During his time at the Cape Town City Engineer’s Department, Wall was responsible for the design and construction of numerous housing, township services and amenities projects. Notably, he was part of the team which heavily revised the then current
Professor Kevin Wall (middle), with Mmamoloko Kubayi-Ngubane, Minister of Science and Technology (right), and Dr Phil Mjwara, director general, Department of Science and Technology (left), after winning the NSTF Lifetime Award
planning and engineering standards, moving away from traditional design to create a more progressive and socially just urban development, with better use of space, and utilising the savings to provide a higher standard of public amenities. This new transdisciplinary way of thinking allowed those with different skill sets to assist each other earlier in the planning stages. The success of the innovative Cape Town development led the Council for Scientific and Industrial Research (CSIR) to base much of its 1983 guideline on infrastructure standards on its lessons. (The CSIR’s “Red Book”, updated and expanded several times, continues to be the definitive guideline for residential development planning and engineering.) A passion for maintenance After three decades in both the public and private sectors, Wall was headhunted by the CSIR for his transdisciplinary and collaborative approach to improving service delivery. It was here that his lifelong drive to raise awareness about infrastructure maintenance was further developed. As a result, the CSIR increasingly drew attention to the strategic contribution of infrastructure asset management – including maintenance – to service delivery.
NSTF Awards The NSTF Awards, a project by the National Science and Technology Forum (NSTF), in partnership with South32, honour and celebrate outstanding contributions to science, engineering, technology and innovation in South Africa. The awards honour and celebrate, among others, research and innovation, green economy and environmental sustainability, water management solutions, sustainable energy, and technology transfer.
Wall was involved in many areas and projects during his time at the CSIR. Notably, he led the team that piloted the social franchising partnership model for creating and nurturing emerging microenterprises to maintain low-technology water and sanitation infrastructure, as well as to develop skills for jobs at the lowest socio-economic levels. “This type of model hadn’t been done with infrastructure maintenance and is still the largest example in the world,” says Wall. He believes the model’s potential is vast, both from public and private sector perspectives, but it first requires the political will to budget for maintenance. Wall, now an Extraordinary Professor at the University of Pretoria’s Department of Construction Economics, is currently part of a pilot, under national Treasury, for municipal service delivery improvement. S E P T/O CT 2018
49
WISA
Giving back to communities
F
ollowing on from the Women in Water workshop held in November 2017, the WISA Water Science Division (WSD) has been ramping up the conversation around making a difference in the lives of communities, particularly for women and children. To assist in achieving this, the WSD held a workshop at the recent WISA Conference to provide feedback on some of its recent initiatives. The aim is to look outside the traditional engineering scope of water at the full value chain, including health aspects, agriculture and collection of water.
The WISA Water Science Division is calling on water professionals to pledge their time and resources to give back to communities and contribute to solving the challenges facing the South African water environment. 50
SE PT /O CT 2018
Giving back to communities Through its Women in Water programme, the WSD facilitated the donation of 23 Hippo Rollers to food cooperatives in the Johannesburg area late last year. These were donated by the Paper Manufacturers Association of South Africa (Pamsa), Food and Trees for Africa (FTFA), Aqua Resources, as well as Hippo Roller itself. “We had a very positive response from our Women in Water event and – based on this, the success of the Hippo Rollers and the enthusiasm of WISA – we decided to continue to showcase
the initiative at the 2018 WISA Conference,” says Ayesha Laher, chair, WSD. FTFA, Pamsa and Hippo Roller all attended the workshop to provide feedback, as did some of the recipients. One recipient, Violet Phala Mabaso, or Mam Vi as she is known in her community, received her Hippo Roller to assist with her food garden cooperative in Alexandra. She has since been given a plot of land to farm in Eikenhof by the City of Johannesburg and is in need of water testing and irrigation. FTFA echoed a similar call for water professionals to assist with installations, drilling and irrigation systems for subsistence farmers. Getting involved Laher called on WISA members to donate more than money – to donate their time and expertise by volunteering to assist with community projects and developing solutions to local challenges. “We are living on a continent with a huge lack of sanitation and access to basic water. We need to begin taking a multifaceted approach. We are more than just members of WISA; we have experience and expertise that can benefit communities.” Laher points out that a design as simple as the Hippo Roller can make a huge difference in people’s lives. “We don’t need engineers to design big treatment plants. It’s the small things – we need decentralised solutions suitable to our conditions and the needs of the communities around us.”
It could be something as simple as spending time educating communities on the value of water or doing yield testing to determine the best locations to sink boreholes in water-scarce areas. “It doesn’t have to be high-grade engineering,” she stresses. Effective collaboration To continue their efforts, the WSD will be hosting a joint conference with the University of Johannesburg’s Department of Applied Chemistry on 11 September. This will involve presentations on research and technologies from the WSD, as well as students’ research initiatives. “The idea is to create a platform for WISA members with technical industry knowledge to interact with research institutions and students. It is important for industry and universities to understand each other’s needs, so that research can address the gaps,” explains Laher. “I believe that if we can make a difference to even one person, like Mam Vi, it will build momentum. And if we can get young people and students involved, we can continue this initiative.” The work of the WSD has now been taken up by the WISA Gauteng Branch, which will continue to drive these initiatives forward.
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