Water Journal August 2015

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Volume 42 No 5 AUGUST 2015

Journal of the Australian Water Association

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Contents regular features From the AWA President

Putting A Real Value On Water Peter Moore

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From the AWA Chief Executive

contents

National Water Policy Summit To Address Key Water Issues Jonathan McKeown

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water journal ISSN 0310-0367

MANAGING EDITOR – Anne Lawton Tel: 02 9467 8434 Email: alawton@awa.asn.au TECHNICAL EDITOR – Chris Davis Email: cdavis@awa.asn.au

My Point of View

The Great Divide – Political Will And Water Industry Vision Ian Law

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CrossCurrent

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CREATIVE DIRECTOR – Mike Wallace Email: mwallace@awa.asn.au

Postcard

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SALES & ADVERTISING QUERIES – Michael Seller Email: mseller@awa.asn.au

Industry News

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CHIEF EXECUTIVE OFFICER – Jonathan McKeown EXECUTIVE ASSISTANT Email: ea@awa.asn.au

Young Water Professionals

Megatrends ... Breaking It Down From A Buzz Word Robbie Goedecke

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AWA News

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AWA International News

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Water Business

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New Products And Services

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EDITORIAL BOARD Frank R Bishop (Chair); Dr Andrew Bath, Water Corporation; Michael Chapman, GHD; Dr Dharma Dharmabalan, TasWater; Wilf Finn, Norton Rose Fulbright; Robert Ford, Central Highlands Water (rtd); Ted Gardner (rtd); Antony Gibson, Orica Watercare; Dr David Halliwell, WaterRA; Sarah Herbert, Shelston IP; Dr Lionel Ho, AWQC, SA Water; Des Lord, National Water Commission; Dr Robbert van Oorschot, GHD; John Poon, CH2M Hill; David Power, BECA Consultants; Dr Ian Prosser, Bureau of Meteorology; Dr Ashok Sharma, CSIRO; Rodney Stewart, Griffith School of Engineering; Diane Wiesner, Jamadite Consulting.

PUBLISH DATES Water Journal is published eight times per year: February, April, May, June, August, September, November and December. Please email journal@awa.asn.au for a copy of our 2015 Editorial Calendar.

EDITORIAL SUBMISSIONS Acceptance of editorial submissions is at the discretion of the Editors and Editorial Board.

• Technical Papers & Technical Features: Chris Davis, Technical Editor, email: cdavis@awa.asn.au AND journal@awa.asn.au

Optimum Water Reclamation Plant (OWRP).

Technical Paper Submission Guidelines Technical Papers should be 3,000–4,000 words long and accompanied by relevant graphics, tables and images.

For more detailed submission guidelines please email: journal@awa.asn.au

feature articles Changing Supply & Demand For Water In The Southern MDB

volume 42 no 5

Impact On Water Market Prices Louise Barth, Ryan Gormly & Chris Olszak

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Drought And Water Allocation Markets

Evolution and recent developments in Australia’s water markets Rod Carr

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Australia Needs A Plan To Protect The Outback’s Precious Water

Why We Should Be Protecting An Iconic Resource Jenny Davis

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Water Reuse In South Africa

Gaining Community Support Is Still A Challenge Jo Burgess

John Radcliffe

technical papers cover Australia’s outback is an iconic part of our history, home to indigenous communities and a range of increasingly threatened wildlife. So what are we doing to protect our remote water resources?

General Feature Submission Guidelines General Features should be 1,500–2,000 words and accompanied by relevant graphics, tables and images.

For more details please email: journal@awa.asn.au • Water Business & Product News: Michael Seller, Sales & Advertising, email: mseller@awa.asn.au

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ADVERTISING Advertisements are included as an information service to readers and are reviewed before publication to ensure relevance to the water sector and the objectives of AWA.

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PUBLISHER Australian Water Association (AWA) Publishing, Level 6, 655 Pacific Hwy, PO Box 222, St Leonards NSW 1590; Tel: +61 2 9436 0055 or 1300 361 426, Fax: +61 2 9436 0155, Email: journal@awa.asn.au, Web: www.awa.asn.au

conference report First Asian Water Reuse Symposium

• General Feature Articles, Industry News, Opinion Pieces & Media Releases: Anne Lawton, Managing Editor, email: journal@awa.asn.au

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COPYRIGHT Water Journal is subject to copyright and may not be reproduced in any format without the written permission of AWA. Email: journal@awa.asn.au DISCLAIMER AWA assumes no responsibility for opinions or statements of fact expressed by contributors or advertisers. Mention of particular brands, products or processes does not constitute an endorsement.

AUGUST 2015 water

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From the President

PUTTING A REAL VALUE ON WATER Peter Moore – aWa President A workshop held as part of Ozwater’15 gave those present an understanding of the severe droughts being experienced in California and in parts of Brazil, specifically São Paulo, a city of 10 million plus people in danger of running out of water.

Subsequently the Association hosted a group of companies to the American Water and Wastewater Association (AWWA) Conference in Anaheim, California, to showcase some of the capability Australia has in water efficiency. By all reports it was a successful trip (see page 23 for a report) and built on the delegation led by our then President Graham Dooley in late 2014. The Americans appreciate Australia has a lot to offer in dealing with all aspects of managing through a drought.

Back home, it is staggering to think that something like 70 per cent of Queensland is currently drought-affected – and yet I suspect most Australians are oblivious to this as they are not currently impacted by water shortages.

This brings me to the main focus of this article: how do we get politicians (and the community as a whole) to really value water and, in particular, what has been achieved in industry changes?

The Australian Water Association will shortly be assessing the views and attitudes of consumers about water through a new consumer survey. The results of this survey will help the water sector shape a wider community campaign to value water as a major economic driver, as well as a national asset to be managed sustainably.

Regarding both the drought in California and the current drought in São Paulo, it’s frustrating to realise in hindsight that remedial actions could have been put in place in the lead-up to these situations had the decision makers planned for the

water AUGUST 2015

worst case and not lived in hope that the rain will come. In each case, the scenario developed over a number of years.

On the positive side, it’s truly amazing what people can do when put under pressure. The Millennium drought saw significant changes to the way people use, manage and trade water. We adapted, worked together and came up with new governance arrangements. We came to recognise new community values, such as the importance of local sporting facilities to the wellbeing of the community. We finally made significant progress in the development and implementation of the Murray-Darling Basin Plan.

But then it rained, the drought was suddenly over, and many forgot all the good work that had been done in valuing water and started to go back to their old ways. We’ve seen politicians asking people to use more water – and even some suggestion that the excellent governance developed for the Murray-Darling Basin Plan is being relaxed. Most important is the demise of the National Water Commission. So much good work begun, so much still to do…

I appreciate that this is somewhat a cynical view and I’m sure there are many places where the good work continues. This is particularly true in Western Australia – although it hasn’t rained in much of south-western Western Australia where dam levels are still declining with effectively no runoff to mid-July.

But why can’t we make the hard decisions that will see us continue to be world leaders in water management? There are many significant issues relating to water that we need to face as a nation.

The Association’s National Water Policy Summit to be held in Melbourne 6–7 October will be an ideal opportunity to consider and discuss these matters.

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From the CeO

NATIONAL WATER POLICY SUMMIT TO ADDRESS KEY WATER ISSUES Jonathan McKeown – aWa chief executive One of the strengths of the Australian Water Association is that our members come from right across the water sector, including in the areas of urban, regional and rural water management. By harnessing this diversity of expertise we perform an important function as the peak national water body – namely, to consider, discuss and prioritise water issues that are of national significance.

Many of these issues arise from policy decisions that governments make, while others come from events or circumstances that influence governments to make or change policy. The role of the Association is to analysis these issues, advocate how they affect our members and stakeholders, and pursue outcomes that protect the sustainable use of Australia’s water.

Over the past months I have met with a large number of senior executives and individuals from across our membership to hear first-hand their own views on the policy issues facing our sector.

Some of the issues repeatedly raised included: • The need for continuing investment in water infrastructure across urban and rural areas and the importance of understanding the different plans currently under development. These include the Commonwealth Government’s White Papers on the Development of Northern Australia and Agricultural Competitiveness, and the National Infrastructure Plan being prepared

by Infrastructure Australia.

• Many of our water utility MDs have raised the need to ensure our planning and licensing regimes allow for the implementation of watersensitive urban design. This includes a review of the governance and use of stormwater and some clarity on the governance of emerging ‘recreational water’ rights.

• Many of our rural and urban sector leaders have raised the need to improve the ability to share water across urban and rural divides while balancing the access requirements of different water users.

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• Underlying all of these topics is the need to maintain community awareness about the true value of water, the role it plays in Australia’s prosperity, and empowering consumers to articulate their own priorities for water usage.

These discussions, together with insights provided through our national and state policy committees, have formed the foundation for interesting debate at this year’s National Water Policy Summit to be held in Melbourne on 7 October. I encourage all members to join the policy discussion and have your say on both the issues nominated and the outcomes to be pursued by the Association.

From the conclusions reached at last year’s Summit, the Association has provided industry feedback to Accenture on a national strategy for water that will be released as a water blueprint for 2020 Vision.

The Summit’s call for more consistency of regulation between the states and territories led to the AWA Discussion Paper by Minter Ellison on the subject that was released at Ozwater’15 with discussions continuing with state and territory governments. The call for a Regulators Forum was implemented and will continue next year with another Forum to be held at Ozwater in Melbourne in May, and yet another at the World Water Congress in Brisbane in October. Finally, last year’s Summit called for engagement with the wider community to understand evolving perceptions on major water issues that resulted in the new AWA National Water Consumers Survey.

This year’s Summit will see the release of reports from both the AWA/Deloitte State of the Water Sector Survey, and the AWA/ARUP inaugural National Water Consumers Survey. The joint release of these reports will contrast any differences in perceptions of our water professionals when compared to water consumers. Most importantly, the findings of the National Water Consumers Survey will enable the Association to collaborate with stakeholders to assist the water industry to better engage with consumers so that their priorities and views are heard.

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My Point of View

THE GREAT DIVIDE – POLITICAL WILL AND WATER INDUSTRY VISION … WHAT PROGRESS SINCE NOVEMBER 2011?

Ian Law – Principal, IBL Solutions Ian Law runs his own business, IBL Solutions, is an Adjunct Professor at the University of Queensland, and has consulted widely in Southern Africa, South East Asia, New Zealand and Australia on advanced reuse systems and the necessity to diversify water supply options. He currently serves on the Australian Water Recycling Centre of Excellence’s Research Advisory Committee and, through this, overviews many projects having a ‘potable reuse’ theme.

I last wrote a ‘My Point of View’ article for the November 2011 edition of Water Journal.

Entitled The Great Divide – Political Will and Water Industry Vision, the piece covered the divide between water supply reality and ‘political will’, noting that we must remove this divide if we are to ensure cost-effective and sustainable water supplies into the future.

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generations applaud our initiatives rather than denigrate our poorly made decisions, the results of which they have to live with…” (and, I might add, have to pay for). I want to revisit this article and identify what progress has been made in ‘removing the divide’ over the last three to four years.

Negative Policies Sadly there are still two states (South Australia and Victoria) that have policies in place precluding the potable reuse option from being considered in any mix of water supply options – and this despite the conclusions drawn by the Australian Academy of Technological Sciences and Engineering (ATSE) in its October 2013 report on Drinking Water Through Recycling – The Benefits and Costs of Supplying Direct to the Distribution System, namely:

The article identified that ‘political will’ is to a large extent driven by perceptions of community attitudes, and it was suggested that this should be one area of focused effort on the basis that if the community pushes for a real evaluation of all supply options, the politicians will surely take note. This implies that there must also be a focus on ensuring that the politicians and their advisors then make informed decisions – rather than ones made, often incorrectly, on perceptions of community attitudes.

• ATSE is convinced of the technical feasibility and safety of Direct Potable Reuse (DPR) when properly managed;

The piece concluded with the statement: “Finally, there is a clear need for individuals and/ or organisations to take up an advocacy role to assist in removing the divide and ensure that future

• Governments, community leaders, water utilities, scientists and engineers need to take leadership roles to foster the acceptance of any DPR proposal in Australia.

• DPR should be considered as an available water supply option for Australian towns and cities; • The pre-emptive exclusion of DPR from consideration in some jurisdictions in Australia should be reviewed; and

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My Point of View

This report has received wide acceptance in the water industry, but has it struck a chord in the decision-making circles?

Another blow to resolving this divide was the closure of the office of the National Water Commission (NWC) in December 2014, a body that was responsible for driving water reform in Australia and for assisting in the effective implementation of the National Water Initiative that came into force in 2004. It was pleasing to see both the Water Services Association of Australia (WSAA) and the Australian Water Association making submissions in support of retaining the NWC, even if they were not successful.

Positive Moves On the positive side, the Water Corporation in WA has run a very effective technology and community outreach program, with the outcome being the construction of the 14GL/annum Beenyup groundwater replenishment project that is due to be commissioned in late 2016. It was refreshing to see video clips of responsible ministers and their minders at the Beenyup Visitor Centre espousing the value of the project and how wide the community support for it was.

Another positive step has been the recent completion of the Australian Water Recycling Centre of Excellence’s (AWRCE’s) major project on overcoming the barriers to reclaimed water being viewed as an acceptable ‘alternative water’ for augmenting drinking water supplies.

The project team has developed a suite of high-quality, research-based and evidenced-based education tools and engagement strategies that can be used by the water industry when considering water recycling for drinking purposes. These educational products are now promoted under the banner of Water360 and are suitable for use by communities, government, media and industry.

Discussions are underway with the WateReuse Association in the US, the Water Research Commission in South Africa, Thames Water in the UK and the PUB in Singapore over the formation of a joint initiative in education on potable reuse using some or all of the Water360 products.

Overcoming the Divide Another bright moment, but this time from outside Australia, was the address by Singapore’s Minister for the Environment and Water Resources, Dr Balakrishnan, at the opening of the Singapore Technology and Innovation Summit in June 2015. Here was a Minister

who was walking in step with the country’s water utility – the Public Utilities Board (PUB) – and who displayed a thorough knowledge of the problems facing Singapore in the water and energy areas and was prepared to engage with the audience and readily share his views. Granted that Singapore is very different to Australia in many ways – but it was refreshing to listen to a politician and, in this case, a government minister, who has overcome the ‘divide’.

So, how can we in Australia overcome this divide?

I suggest we need to start a national discussion on the subject, involving water industry practitioners across the board, community leaders and State and Federal politicians together with their minders/advisors, and build on the success of the Beenyup project in WA and the learnings from others both in Australia and overseas.

This idea came about after reading an article in the Sydney Morning Herald on 30 June entitled: Ex-Treasury Head Martin Parkinson Slams Government, Labor For Putting Politics Before Economy. Substituting the words ‘water security’ for ‘economy’ brought this article into focus for me, as much of what he was quoted as saying could apply equally to our industry, particularly the sentence: “We need to have a much more mature debate, and I hope we can get there, because if we don’t then we may well have quite a different set of circumstances”.

Some might well question the necessity for this, given that water and water supply issues have to a large extent gone off the boil in both the media and government policy. However, given that we are headed for another El Niño event and are already experiencing climate variability while our population continues to increase, I believe now is the time to discuss and debate the issue openly – starting in Victoria and South Australia – the aim being to ensure we evaluate all water supply options to ensure security of supply into the future.

Who will lead this discussion? The Australian Water Association immediately springs to mind – and there are certainly signs that the Association’s modus operandi has changed in recent times.

Some might say that it is too broad a church to do it, but I believe that a body led by the Association, and including representatives from WSAA, the AWRCE and former members of the Private Sector Water Forum (PSWF, a body set up by the AWRCE in 2012) would be eminently suitable and capable of leading the charge. The question is: will they do it? I certainly hope so.

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CrossCurrent The Australian Climate Roundtable, an alliance of major

International

Australian business, union, research, environment, investor and social groups, has come together to put the climate policy debate on common ground and offer a way forward. The Australian Climate

Global water demand is projected to rise by 55 per cent between 2000 and 2050, the Global Water Forum has cited, while nearly 1 billion people in developing regions still have no access to clean, safe water. The Organisation for Economic Co-operation and Development (OECD) in its report stated that by 2050 the number of people living in river basins that are under water threat is predicted to reach 3.9 million.

Some 650 million people are still without an ‘improved’ source of water and 2.4 billion do not have a basic, hygienic toilet, a joint monitoring program report by Unicef and WHO has revealed. The regular update is the last under the Millennium Development Goals, a set of UN ambitions that set out in 2000 to halve the proportion of people without access to water and sanitation, among other goals. As these goals expire this year, the goal on water has been met overall, but with wide gaps remaining, particularly in the Pacific and Sub-Saharan Africa. The goal on sanitation, however, has failed, particularly in the Pacific and sub-Saharan Africa. At present rates of progress it would take 300 years for everyone in sub-Saharan Africa to get access to a sanitary toilet.

Roundtable discussions have involved the Australian Aluminium Council, the Australian Conservation Foundation, the Australian Council of Social Service, the Australian Council of Trade Unions, the Australian Industry Group, the Business Council of Australia, The Climate Institute, the Energy Supply Association of Australia, the Investor Group on Climate Change and WWF Australia.

Investment in urban and regional infrastructure will be better informed with the release of the Progress in Australian Regions – State of Regional Australia 2015 and State of Australian Cities 2014–15 publications. The publications provide an understanding of the nation’s overall economic and social wellbeing. The economic output of our major cities has grown and their national importance remains extremely high, although mining activity in regional Australia has seen the overall percentage contribution by major cities to Gross Domestic Product (GDP) dip slightly.

The Ricegrowers’ Association of Australia (RGA) says it is leading The Australian Water Partnership (AWP) will have a joint presence with the MDBA at World Water Week in Stockholm on 23–28 August.

This event presents an important opportunity to network and partner with other Australian water organisations and people to discuss and share our water reform journey and growing water challenges.

There will be an AWP and MDBA stand, where Australian sessions and speakers will be promoted daily. For more information please contact awp@ewater.org.au.

the charge to bring commodity-based CEOs together to address future policy solutions surrounding the ongoing implementation of the Murray-Darling Basin Plan. RGA’s Executive Director, Dean Logan, says one of the great strengths of working in regional Australia is the ability as CEOs to get together and talk through issues of mutual significance and concern. “Over the last two weeks I’ve met with and discussed concerns regarding the Murray-Darling Basin Plan process with CEOs across five major commodity sectors equating to tens of billions of dollars of investment,” he said.

National

Some of Australia’s best researchers will work collaboratively with industry partners to deliver important outcomes for the nation,

The Australian Government has set up a National Water Infrastructure Development Fund with $500 million for water infrastructure, including dams, through the Agricultural Competitiveness White Paper. Minister for Agriculture, Barnaby Joyce, said $50 million would be allocated to support the planning necessary to decide on viable projects for investment, and $450 million was available to construct water infrastructure in partnership with states and territories. "Water is the most basic input for life – this funding will help supply water for communities, agriculture and industry," Minister Joyce said.

with the announcement of 252 new research projects awarded a total of $86.9 million. Minister for Education and Training, the Hon. Christopher Pyne MP, announced the funding, which has been awarded through the Australian Research Council’s (ARC) Linkage Projects scheme. This type of collaborative research connecting industry with university researchers is vital to Australia’s prosperity and the jobs of the future.

Disposable wipes are costing authorities tens of millions of dollars as more people flush them down the toilet, clogging A comprehensive national picture of recycled and desalinated water sources for over 350 sites across the country is now available online, following the launch of a new web tool. The Climate Resilient Water Sources web portal on the Bureau of Meteorology's website captures both publicly and privately owned and operated recycled and desalinated water sources in Australia, and allows users to search information on capacity, production, location and use of these alternative water sources in their local area. Climate Resilient Water Sources has been jointly developed by the Bureau of Meteorology, the Australian Water Recycling Centre of Excellence, the National Centre for Excellence in Desalination and the CSIRO. To view the portal please go to: www.bom.gov.au/water/crews

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pipes and polluting waterways. Manufacturers and sewage companies across the country are scrambling to fix the problem, fearing just one colossal blockage could cause hundreds of thousands of dollars worth of damage to a system already under strain. Water Services Association of Australia Executive Director, Adam Lovell, said authorities around the country were struggling to cope. "We are unfortunately seeing an increasing frequency of sewage blockages," Mr Lovell said. "Sydney Water estimates it costs around $8 million a year to fix blockages caused by wet wipes, and they find 75 per cent of their sewage blockages involved wipes of some description.”

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CrossCurrent

Queensland The Queensland Government’s 2015–16 Budget includes $52.1 million for much-needed drought relief for primary producers.

Minister for Agriculture and Fisheries, Bill Byrne, said the greatest challenge currently facing the sector was the prolonged drought across much of the state. “The State Government is responding to the most widespread drought on record,” Mr Byrne said. “More than 80 per cent of Queensland is drought declared, covering 32 entire local government areas and three part local government areas.”

New South Wales The Australian Government has partnered with the New South Wales Government to deliver more investment to ensure water savings for the state’s Great Artesian Basin, one of the largest underground water reservoirs in the world. As a result of a new agreement, New South Wales will be eligible to receive a share of almost $16 million to help assist landholders rehabilitate remaining free-flowing bores in the state.

NSW Minister for Primary Industries, Lands and Water, Niall Blair, has announced the formation of DPI Water, in line with a new direction for managing water in NSW. Mr Blair said DPI Water will replace the former NSW Office of Water and will continue to remain within the Department of Primary Industries. “This is more than just a name change – it’s about a renewed focus on how water is managed, and DPI Water will lead this fresh approach,” Mr Blair said.

Hydrogeologist Dr Richard Cresswell has told farmers at a conference in Sydney that the Santos coal seam gas operation in the Pilliga is no threat to the water resource there. Dr Cresswell, formerly of CSIRO, sits on the Federal Government’s expert advisory committee on large coal seam gas projects and was the lead scientist on a CSIRO study of the Great Artesian Basin (GAB).

He is employed by Jacobs Engineering, and his presentation at the conference was sponsored by that company.

Minister for Industry, Resources and Energy, Anthony Roberts, has announced the independent Environment Protection Authority (EPA) has begun its new role as the state’s sole authority responsible for compliance and enforcement of all non-work, health and safety consent conditions for gas exploration and production activities.

Mr Roberts said the NSW Liberals & Nationals Governments outlined the EPA’s new lead role under Action 7 of the NSW Gas Plan. Environment Minister, Mark Speakman, said $6.8 million has been allocated in 2015–16 to support the EPA’s new role.

For more information visit: www.resourcesandenergy.nsw.gov.au

AGL Energy Limited has resumed the transportation of flowback water from its Waukivory Pilot, part of the Gloucester Gas Project in NSW, for lawful offsite treatment and disposal. AGL has engaged Toxfree Solutions, one of Australia’s major waste management service providers, to transport and treat flowback water at its licensed facility,

and subsequently lawfully dispose of the treated water. The flowback water will be taken to Toxfree’s Narangba plant in Brisbane’s north for treatment to the standards set by the Queensland Department of Environment and Heritage Protection and Toxfree’s trade waste agreement. Removal and treatment of the water is expected to take approximately three months. AGL remains in discussion with other waste disposal service providers for options to treat the flowback water and dispose of treated water in New South Wales.

The Independent Pricing and Regulatory Tribunal (IPART) has begun its review of prices that the NSW Office of Water can charge for the monopoly water management services it delivers on behalf of the Water Administration Ministerial Corporation, the legal entity responsible for water management in NSW. The current determination set prices for the period 1 July 2011 to 30 June 2014. In this review, IPART will set prices to apply from 1 July 2016.

Stakeholders are encouraged to make a submission in response to the Issues paper. Submissions are due by 9 October 2015 and can be lodged through the IPART website.

Significant levels of strong painkillers and anti-depressants have been found in tests conducted on water samples in Sydney Harbour. The drugs were found by analysing samples of marine water from 30 sites adjacent to stormwater outlets across the entire Sydney estuary. Scientist Gavin Birch from the School of Geosciences at the University of Sydney said it was the first time this kind of research had been done in Australia. Other drugs found across Sydney Harbour waters included beta blockers and an epilepsy medication. Mr Birch said the findings indicated sewage water may be leaking into the harbour.

MidCoast Water is assessing the merits of developing a major new dam, desalination or water recycling plant by 2030. As part of a regular strategic review, such water infrastructure projects are being considered as ways to secure the Manning-Great Lakes water supply in the shortto-medium term. The water authority said it must ensure water security for coming generations. Acting General Manager Brendan Guiney said public feedback is being sought regarding different options as part of the ‘Our Future, Our Water’ strategic review.

Sydney Water says households will save about $100 each year for four years from July 2016, as part of its pricing plan released recently.

Sydney Water’s proposal, lodged with The Independent Pricing and Regulatory Tribunal (IPART), seeks to reduce customer bills while still delivering high quality services, enhance customer engagement to better align services to meet customer expectations, and modernise regulation to deliver better outcomes for customers.

Hunter Water will invest $1.1 billion into better infrastructure during the next 10 years in the Hunter, to support the increase in the region’s population to one million people by 2050. “The Hunter region is growing and it is important we put in place the right water infrastructure to cater for that population growth,” Minister for Primary Industries, Lands and Water Niall Blair said. The 10-year infrastructure program is detailed in Hunter Water’s 2016–20 price submission to the Independent Pricing and Regulatory Tribunal (IPART), in which the utility has recommended household water prices rise by no more than inflation.

AUGUST 2015 water

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CrossCurrent A Local Aboriginal Land Council has transferred land to a local government utility to improve water supply for the broader community. Under an agreement signed between the Forster Local Aboriginal Land Council (LALC) and MidCoast Water, 1,600 hectares of land will be purchased from the Land Council to develop a new source of water supply for the surrounding communities. The sale of the land will finance social and economic development opportunities for Aboriginal people, who will also retain a perpetual right of cultural access to fish and gather food from the site. The sale of the land will enable the development of the Nabiac Inland Dune Aquifer and water treatment plant, which will provide the community with a diversity of water supply, additional capacity and lower pumping costs.

Australian Capital Territory An inquiry into the ACT’s enlarged Cotter Dam, the Murrumbidgee pipeline and a spillway upgrade at Googong Dam has given the projects qualified approval, despite foreseeable delays and a cost blowout. A report by ACT Auditor-General Maxine Cooper has found the use of a contracting alliance by water utility ACTEW to build the projects was appropriate and effective. The Bulk Water Alliance formed to deliver the projects was comprised of ACTEW, the project designer GHD, and constructors Abigroup and John Holland Group. Ms Cooper found events such as flooding and a geographical fault did not fully account for a 20-month delay and the cost overrun. The final cost of the Cotter Dam project was $410 million, significantly higher than the estimated $363 million.

The auditor general also said delays in concreting and excavation should have been foreseeable. The report found while there were delays in providing project costs to the public, there was no evidence this was deliberate. However, the report said the merits of including the Googong Dam Spillway project in the alliance had not been evidenced.

Canberrans and residents of surrounding councils have been invited to complete an online survey on how they use their lakes and waterways and what they think of water quality. The ACT Basin Priority Project is a joint Australian Government and ACT Government project that is improving long-term water quality in the ACT and the Murrumbidgee River catchment, with funding of up to $85 million from the Australian Government. Complete the survey by 14 August and enter a prize draw for one $1000 and eight $500 gift cards. Go to www.environment.act.gov.au

Victoria A Victorian parliamentary committee in July held a public hearing in Melbourne in relation to the inquiry into unconventional gas in Victoria. The Committee examined the potential economic, social and environmental impacts of onshore unconventional gas development. The Australian Water Association responded to the Victorian inquiry into unconventional gas, highlighting some of the key work the Association has recently done in this area, including the Water & CSG supplement to the April Water Journal, the recent ‘CSG and Water’ breakfast seminar and the upcoming discussion paper Coal Seam Gas and Water Regulation in New South Wales and Queensland. You can view the full submission at www.awa.asn.au

water AUGUST 2015

Western Australia Perth’s drinking water supplies will be boosted thanks to a $21.2 million upgrade to the Jandakot Groundwater Treatment Plant and the installation of a new drinking water bore. WA Water Minister, Mia Davies, said the new bore would provide an additional six billion litres of water each year into the Integrated Water Supply Scheme (IWSS), which was the equivalent of 2,667 Olympic swimming pools.

The WA Government has completed work on a suite of projects worth $113 million to upgrade Karratha's wastewater scheme and increase the amount of wastewater being recycled. Water Minister Mia Davies said projects completed included a major upgrade to the wastewater treatment plant near the light industrial area, new pipelines and upgrades to wastewater pump stations. “The wastewater treatment plant has been upgraded to treat up to 10 million litres of wastewater per day," Ms Davies said.

The WA Government has announced that Denmark will soon have a $15 million water-recycling scheme to irrigate the local golf course and a new tree farm, made possible by Royalties for Regions.

Water Minister Mia Davies and Regional Development Minister Terry Redman said the recycling scheme would recycle treated wastewater from the Water Corporation's Denmark Wastewater Treatment Plant through a new pipeline for use in irrigation.

WA Premier, Colin Barnett, has opened an innovative stormwater harvesting and storage project that will provide a new supply of irrigation water to the expanded Hartfield Park reserve in Forrestfield.

The first stage of the project involves the harvesting and filtering of 46,000 kL of stormwater from a Water Corporation drain before injecting the water into the superficial aquifer below Hartfield Park.

South Australia SA Water Minister, Ian Hunter, has reiterated the State Government will not privatise SA Water, following calls by South Australian Federal Liberal MP Jamie Briggs that he wants to sell off the state’s water utility. “Mr Briggs' comments on Adelaide radio this morning are very concerning,” Mr Hunter said. “Unlike the Liberals who sold off our electricity assets – and now want to sell off SA Water – this State Labor Government will ensure SA Water is owned by the people of South Australia and not sold to an overseas monopoly.”

Consumers could save about $150 a year on their water and sewerage bills if the value of SA Water’s assets is written down, a parliamentary committee has been told. The $13 billion value of SA Water’s assets has been under scrutiny since the former head of the Essential Services Commission of South Australia (ESCOSA) Paul Kerrin accused the Government of propping up its budget by inflating the valuation. Other members of the ESCOSA board have also claimed the asset base is overvalued by about $2 billion. The asset valuation forms a key part of the calculation of household water bills.

ESCOSA has approved SA Water's 2015-2016 revenue control compliance Statement. The Commission has considered the Statement and supporting information provided by SA Water, and is satisfied that it is consistent with the requirements of the 2013-2016

Uncompromising Blockage Protection

Revenue Determination.

SA Water and the River Murray Minister, Ian Hunter, say there has been a great response to the State Government’s new selfread water meter system. Licence-holders in the Eastern Mount Lofty Ranges were recently asked to put in place a new method of recording water meter readings through a self-read system. The majority of licence holders required to provide quarterly reads have submitted readings under the new system.

Member News The National Centre for Groundwater Research and Training (NCGRT) is currently seeking candidates for a limited number of PhD research opportunities in Australia. The Centre is recognised as Australia’s leading groundwater research and training institution with a partnership base including the key federal and state water management agencies and 14 Australian universities. NCGRT is now recruiting the next generation of groundwater specialists to conduct innovative research addressing contemporary issues in groundwater science, management and policy.

SUEZ environnement has announced several management changes, with Mark Venhoek set to commence as CEO in Australia in September 2015. Mark joins the Australian business with extensive experience gained within the SUEZ environnement group across Europe and Asia. He is currently Vice President of the company’s waste operations in China. Meanwhile, David Lamy has been appointed CEO – Water & Treatment Solutions at SUEZ environnement in Australia. David was previously CFO of SUEZ environnement Australia.

He replaces Roch Cheroux, who was appointed to the newly created position of CEO of SUEZ environnement in South East Asia. David brings 15 years of experience within the SUEZ environnement group in Europe, Latin America and Australia.

Jacobs has appointed Morris Taylor as Outside Sales Manager focused on the Water sector. Mr Taylor will be based in the Melbourne office and will provide business development leadership support to Jacobs’ Southern Area water business, while also assisting in the pursuit of significant Design & Construct (D&C) opportunities in other

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parts of Australia and New Zealand. Mr Taylor brings more than 16 years of experience in the water industry, having held various positions ranging from Controls System Engineer to Project Manager.

Power and Water Corporation’s Chief Executive Mr John Baskerville has retired from his role. “Mr Baskerville leaves the corporation in a strong position with many reforms initiated during his two-and-a-half years at the helm,” Power and Water Corporation Board Chair Mr Alan Tregilgas said.

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12

Postcard

POSTCARD FROM VIETNAM – From Grace Tjandraatmadja, Engineers Without Borders In our April 2015 edition we published the first ‘Postcard From Vietnam’ from Grace, who is stationed there as a volunteer working on a project to develop housing support services incorporating access to water, sanitation and climate-resilient shelter. Here is the next instalment to Grace’s tale.

The rains are finally here! After unrelenting heat (36– 38°C every day) over the months of April and May, the monsoon has finally arrived in Ho Chi Minh City. The skies started off a light shade of grey and then darkened until, finally, thick heavy rain poured down with the occasional rolls of thunder roaring in the distance.

The rain signals the arrival of the wet season and brings much-needed relief from the heat. It cools the warm air, washes away air pollution and makes everything feel fresher. Large drops hit the tin roof panels and window-panes of the houses, while rivulets form down walls and across footpaths towards the street.

Cyclists get back onto the roads as the rain eas es.

Street vendors pull their carts back under the eaves of shops. Traffic slows down. Pedestrians and motorbike drivers seek cover under neat shop awnings. Everyone waits for the rain intensity to decrease. The bravest pull out raincoats (plastic ponchos designed to ride motorbikes – they are opaque but have a clear plastic square for the motorbike headlight). Soon a few motorbike riders venture back onto the streets. Taxis and cars continue travelling unaffected. Water sprays as vehicles drive by. Streams form along the edges of streets. Gutters become swollen as water tries to drain down, and some streets turn into temporary streams.

Slowly, as the rain intensity decreases, the sounds of traffic return once more: the honking of cars and motorbikes resumes; the roar of buses rises and mixes with other urban sounds; a radio plays at a distance; chatter resumes among street vendors and raindrops continue to splatter.

The wet season brings regular rainfall to south Vietnam – intense downpours occur almost daily for a few hours, bringing down temperatures to the mid-to-high 20s and providing temporary relief from the heat. It also signals an increase in the number of mosquitoes, as there are more opportunities for stagnant water collection.

For Ho Chi Minh City, which is located over low-lying lands interwoven with canals and marshes, the season also challenges the stormwater drainage system. While there is a system for household rubbish collection, a common practice is for people to throw trash on the street. Street vendors, shop owners and pedestrians often dispose of packaging, leftover drinks and food by throwing them onto the side of the road or into drains.

in Truong Sa Street. Investment ics View from the canal along has improved aesthet e utur astr infr ng eivi -rec stor mwater the more prominent canals. and drainage along some of

water AUGUST 2015

Housing renovation and construction in urban areas often spills onto the streets and debris is washed into the drainage system and into the various canals that feed into the Dong Nai River. An army of street sweepers valiantly sweeps the streets in the mornings and the evenings to collect the rubbish. However, in many areas drains often get clogged and many hold stagnant murky water.

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Postcard

In low-lying parts of town where flooding is more severe, some households have had to resort to raising the floor level to cope with annual inundation (Hardman, 2015). Flooding in such areas also brings increased risks of disease transmission.

There are a number of factors contributing to flooding. To start with, the city is just at or above sea level and in many areas flooding occurs as a result of the combined effect from tidal inflow/sea level rise, intense rainfall and runoff, drainage capacity issues and land subsidence (Phi, 2008).

Investment in large stormwater infrastructure in the city has tried to reduce the frequency of flooding events and flooded areas (Duc and Truong, 2003), but challenges persist and are expected to increase in severity: climate change projections indicate Given the high cost of land and property, low-income families often build homes along canals and river banks, increasing rainfall intensity (0.8mm/yr) and rising sea which increases their vulnerability to flooding. levels; and as a growing city of nine million people, heavy urbanisation in Ho Chi Minh City brings its own issues: more construction, more impervious surfaces, heat island effect and increased groundwater exploitation (Phi, 2008).

Dealing with such challenges will require more than just technological solutions. It will require multi-pronged and coordinated efforts across government agencies, planners and community; importantly it needs a shift in mindset on stormwater management (less reliance on end-of-pipe solutions alone, more consideration of integrated water management interventions) and greater awareness by the population on how their behaviour impacts their local environment and living conditions. Let’s hope that the pace of environmental awareness may eventually catch up with economic development.

REFERENCES Hardman J (2015): Delta Blues Part 1: The Battle To Keep Ho Chi Minh City Above Water, WWNO New Orleans Public Radio, wwno.org/post/deltablues-part-1-battle-keep-ho-chi-minh-city-above-water.

Ho Long Phi (2008): Impacts of Climate Changes and Urbanisation on Urban Inundation in Ho Chi Minh City, 11th International Conference on Urban Drainage, Edinburgh, Scotland, UK, 2008, web.sbe.hw.ac.uk/staffprofiles/bdgsa/11th_International_Conference_on_Urban_Drainage_CD/ICUD08/ pdfs/713.pdf.

Hiep ND & Truong PT (2003): Water Resources and Environment In and Around Ho Chi Minh City, Vietnam, Electronic Green Journal, 1, 19.

ributors to run-off. surface coverage are key cont High density and impermeable

14

Industry News

Climate-resilient water sources data now available

“The Goyder Institute has proven its value as an independent expert science advisor to Government on water related issues,” she said. “We have delivered significant research achievements across industry, environment, urban water and climate change.

“Water shapes the quality of life and the economic interests of our state. The institute is providing quality, evidence-based science on the water management issues important for South Australia.”

The Bureau of Meteorology has launched a Climate Resilient Water Sources web portal, an interactive site providing comprehensive mapping and information of desalinated and recycled water sources for over 350 sites across Australia, both publicly and privately owned and operated. Users can access the portal (www.bom.gov.au/water/ crews) to search information on capacity, production, location and use of these alternative water sources in your area.

Established in 2010, the Goyder Institute helps deliver expert scientific advice to Government in a format that helps shape policy and decision-making. The organisation is a partnership between the South Australian Government through the Department of Environment, Water and Natural Resources, and the CSIRO, Flinders University, the University of Adelaide and the University of South Australia.

This information will inform the Australian community, government and the water industry of the contribution that these sources make to secure water supplies for current and future residential, industrial, mining, commercial and agricultural needs. Diversifying Australian water supply is important to our long-term water security.

South Australian Treasurer Tom Koutsantonis said the funding recognises the institute’s vital work in helping South Australia secure and manage its water resources.

Climate Resilient Water Sources is jointly developed by the Bureau of Meteorology, the Australian Water Recycling Centre of Excellence, the National Centre for Excellence in Desalination and CSIRO. Climate-resilient water sources will play an important role in increasing water security, lessening climate variability impacts on water availability. Either as part of large centralised supply systems or small decentralised schemes, they are increasingly relied on to supply or secure Australia’s water demands.

“The portal improves our understanding of how climate-resilient water sources can play a greater role in regional water security and supply,” said Dr Mark O’Donohue, CEO of the Australian Water Recycling Centre of Excellence. “Before this project we didn’t have a clear picture of how much recycled and desalinated water could be produced in each state and territory. What is particularly interesting is there are hundreds of small and large recycled water and desalination systems around Australia providing water for farming, irrigation, heavy industry, waterway health and drinking,” he said.

Plant owners and operators can add and update their data directly to the portal’s database, which is then linked to the website. The Bureau will also update data from the National Water Performance Report. The Bureau’s Improving Water Information program is building a comprehensive and reliable picture of Australia’s water resources to support policy and planning.

Goyder Institute TO continue ITS RESEARCH WORK IN South Australia South Australia’s Goyder Institute for Water Research has welcomed a decision by the South Australian Government to extend its funding for a further four years.

Goyder Institute Director, Dr Michele Akeroyd, said the Government’s decision would enable the institute to continue its valuable work and help the state maintain its position as a world leader in water research.

water AUGUST 2015

“South Australia’s reputation as a leader in water resource management comes in large part from the work of the Goyder Institute,” Mr Koutsantonis said. “Science provided by the Institute was central to South Australia’s success in our fight against the Commonwealth and upstream states to save the River Murray.”

Water and the River Murray and Climate Change Minister, Ian Hunter, said the institute’s ongoing funding meant it will play a key role in the state’s increased efforts to both prepare for, and capitalise on, the effects of climate change.

“To address climate change, we will need to base our policies on the best available science, and the Goyder Institute’s flexibility means it can greatly assist in this area,” he said.

“With drier than average conditions on the way, as well as current low water storage levels, the institute’s research into irrigation efficiencies, water quality and environmental watering requirements will be important in making sure we get the best value from our agricultural, tourism and environmental strengths.

“We also want to involve the Goyder Institute in our ambitious goal of making the City of Adelaide the world’s first carbon-neutral city.”

Revised Drinking Water Guidelines for Tassie The Department of Health and Human Services (DHHS) has revised and published the Tasmanian Drinking Water Quality Guidelines (Guidelines). These legally enforceable Guidelines are closely aligned with the Australian Drinking Water Guidelines. Issued under the Public Health Act 1997 they are aimed at protecting public health through the management of drinking water.

A major change from the previous version is the requirement for the water corporation, TasWater, to have their Drinking Water Quality Management Plans externally audited by auditors approved by the Director of Public Health. Suitably qualified water quality auditors are encouraged to contact the Department’s State Water Officer (Cameron.dalgleish@dhhs.tas.gov.au) to obtain further information about the auditing requirements, prerequisites, application and approval process. The Guidelines can be downloaded at www.dhhs. tas.gov.au/publichealth/water/drinking/guidelines.

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Industry News

Mott MacDonald working on AU$50M project IN PNG Mott MacDonald has begun preparing the detailed design of the solids management component of a new sewerage treatment plant in Port Moresby, Papua New Guinea. The project, undertaken on behalf of the Independent Public Business Corporation, forms part of the wider Port Moresby Sewerage System Upgrade Project (POMSSUP).

Rapid urbanisation in Port Moresby, due to an increase in population and associated socioeconomic activities, has led to a rise in the volume of sewage effluents. Due to this, the existing sewerage system needs to be upgraded to reduce and prevent untreated sewage from being discharged into the sea. This will protect the local marine ecosystem, as well as the livelihoods and sources of income of the local people, while also reducing health risks.

Stage 1 of the POMSSUP scheme will see the construction of the sewage treatment plant in Kila Kila, capable of treating flows of 18,400 cubic metres per day for approximately AU$80 million. Infrastructure consisting of 13 pumping stations, a 13km trunk sewer and 15km branch sewer will also be constructed or rehabilitated as part of the project.

For Stage 2 of the project, Mott MacDonald has developed technical solutions to expand the treatment plant capacity to 25,700 cubic metres per day, as well as reducing solids produced at the site and generating biogas for power generation for an approximate project value of AU$50 million. The consultancy will design the process, mechanical, hydraulic, civil and building services for the primary sedimentation tanks, dissolved air flotation pre-thickening units, gravity belt thickeners, anaerobic digesters and gas engines, including all associated equipment and pumps.

Ed Ptolomey, Mott MacDonald¹s project director, said: “We will carefully tailor our design to cater for local climatic events, such as severe weather conditions, ambient temperature and potential earthquakes. We will also design a system that is suitable for the local operating environment, skill levels and supply chains. Sustainability is seen as key to the long-term success of the scheme through training the local community and workers in awareness activities to learn effective and practical sanitation and hygiene practices.

“On this project, we will utilise our experience of designing treatment plants featuring solids management systems, such as the Rosedale wastewater treatment plant expansion in New Zealand,” Ed added.

Construction of the sewerage treatment plant upgrade is due to be completed in the summer of 2018.

New Principal for SLR International environmental consultancy, SLR Consulting Australia, has recently grown its Hydrogeology capability with the appointment of Derwin Lyons as Principal.

Derwin has 10 years’ experience as a hydrogeologist, and has previously worked with Jacobs (formerly Sinclair Knight Merz) on a variety of projects in the oil and gas, mining and minerals, and natural resource management sectors. The SLR team will benefit from Derwin’s particular expertise in hydrogeological conceptualisation, field program design, groundwater dependent ecosystems, and groundwater resource management.

Derwin’s experience spans groundwater impact assessment, baseline monitoring and reviews, environmental impact statements and water supply development across Asia Pacific. Typical project work includes developing conceptual hydrogeological models for mining and CSG developments in Queensland, managing groundwater supply developments in South Australia and Queensland, undertaking GAB springs studies in Queensland, and conducting groundwater impact assessments for projects in South Australia, Queensland and the Northern Territory.

Operations Manager – Land and Water (APAC), Colm Molloy said: “We’re looking forward to working with Derwin and utilising his specialist expertise. His experience will be a great asset in continuing to deliver our growing hydrogeology capabilities in Asia Pacific.”

Derwin is joined in the Brisbane Office by Samantha Solley, who has recently been appointed Senior Consultant in the Environmental and Social Impact Assessment team.

AUGUST 2015 water

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Industry News

New Managing Director for Westernport Water

GHD and CRA complete integration PROCESS

The Board of Westernport Water has announced the appointment of Peter Quigley as the new Managing Director of Westernport Water. Peter comes to Westernport Water with over 25 years of senior management experience in the public and private sectors, including eight years in the water industry.

GHD and Conestoga-Rovers & Associates (CRA) have completed integration of their operating platforms, with the merged company operating as GHD having started on 1 July 2015. The GHD name and brand have been adopted by the CRA family of companies, including Inspec-Sol.

Westernport Water’s Deputy Chairman Roland Lindell said: “The Board is pleased to appoint Peter to the position of Managing Director after a comprehensive recruitment process that attracted many first-rate applicants. As the current CEO for Gippsland Medicare Local, Peter joins Westernport Water with an in-depth understanding of the service industry. Peter has held several senior positions locally with Latrobe City Council, Gippsland Water and the Department of Human Services and the Department Planning & Development.”

The integration has created one of the world’s leading privately owned engineering, architecture, environmental and construction services companies, with more than 8,500 people globally and 4,000 in the US and Canada.

“I’m looking forward to leading the team at Westernport Water, and empowering the workforce to deliver a positive customer experience,” Peter said. “As a Gippsland local with strong community ties, I understand the importance of community engagement and the benefit it can provide to customers and the broader community.”

Peter begins in his new role on 1 September and will succeed Murray Jackson as Managing Director, with Murray completing seven years in the top position.

“Under Murray’s leadership Westernport Water has secured the region’s water supply and put measures in place to address future growth, while providing improved water and sewer services to customers across its service area,” Roland said. “On behalf of Westernport Water, management, staff and the Board, I would like to acknowledge Murray’s outstanding contribution to Westernport Water and the Victorian Water industry and wish him well in retirement.”

Ian Shepherd, GHD’s CEO, said: “This is one of the largest true mergers to have occurred in our industry. We have added significant growth and scale to our business, while retaining the advantages of our private, employee-ownership business model for creating value for our clients and people. “Our merger has already presented numerous opportunities to deliver additional value for our clients.

We are positioned for further growth, as we continue to expand our services across our clients’ asset value chain.”

Steve Quigley, GHD’s General Manager in North America and formerly CRA Principal, says, “As part of our integration, we have combined systems and processes, building on the best practices of both organisations. Together, we have created a connected global network of 200+ offices across five continents.”

Grundfos gears up for growth in the Asia Pacific Danish pump manufacturer Grundfos has announced a new structure to reinforce its market position for sustainable and profitable growth.

The Asia Pacific operations will now come under four geographical clusters: East Asia, South Asia, Oceania and Indochina. The reorganisation aims to improve customer centricity with a stronger focus on local requirements, strengthen business efficiencies with improved resource allocation and increase market competitiveness with better economies of scale.

The East Asia cluster comprises Japan, Korea, the Philippines and Taiwan; South Asia covers Indonesia, Malaysia and Singapore; Australia and New Zealand comes under Oceania; while Indochina will spearhead business activities in India, Thailand, Vietnam and other emerging markets such as Bangladesh, Bhutan, Cambodia, Laos, Maldives, Myanmar, Nepal and Sri Lanka. The Asia Pacific Regional (APREG) headquarters remains in Singapore.

The new structure considers the commonalities in technological requirements, as well as cultural demographical profiles that exist within each geographical cluster, allowing Grundfos to concentrate on opportunities and challenges that are unique to each cluster.

Deputy Chair Roland Lindell (left) and incoming Managing Director Peter Quigley.

water AUGUST 2015

“In Japan, Korea and Taiwan, for example, where pumps run on 60Hz electric motors, it makes sense to localise the engineering expertise for our 60Hz product range, so as to reap better operational synergies and deliver more agile technical support to our East Asian customers,” says Mr Okay Barutçu, Grundfos’ Regional Managing Director for APREG.

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18

AWA News

MEGATRENDS … BREAKING IT DOWN FROM A BUZZ WORD Robbie Goedecke – AWA YWP National Representative Committee President

If you read the news as often as I do you would no doubt be aware that our future is starting to be defined by ‘megatrends’, influencing the way we think, act, create, design and operate as a society. A megatrend is a force of development that has the ability to change the way the world operates and impacts most greatly on businesses and the economy.

KPMG has identified a number of megatrends which, when categorised, refer to how individuals, the global economy and the physical environment will be the dominating factors over coming decades. Here in Australia, this becomes relevant as we transfer from a resource-intensive economy into a services-based economy. In our Young Water Professionals workshop at Ozwater, we were able to dig a little deeper and understand how these changes will impact the water industry.

I want to highlight three key megatrends: Rise of the Individual, Public Debt and Climate Change.

Rise of the Individual If we consider that it was only 13 years ago that the first iPods were released, individuals are becoming increasingly driven by technology and are able to access all forms of information readily and make decisions at a more rapid pace. How we as an industry respond to changes in expectations of service and quality from our customers will be important as they become more responsive to the need for delivering more with less. Emphasis will need to be placed on ensuring individuals are well informed of the future availability of freshwater resources and the need to place a higher economical value on water as a commodity.

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Public Debt According to current trends, the world will reach net public debt levels of 98 per cent of Gross Domestic Product (GDP) by 2035.

The inability of Greece to pay down debts of $330 billion is one of many examples. This has ramifications for a society perceived as debt ridden with the inability to control spending, putting further strain on future economies to pay down these loans. The water industry will need to respond by putting in place economic policies that rationalise spending and ensure that net public debt is always within reach of being clawed back.

Climate Change Anthropogenic climate change has the ability to further economical and social consequences for the water industry. Through projected changes in the climate, the costs of dealing with extreme weather events could rise to as much as one per cent of world GDP by 2050. This will result in greater levels of debt if investment in both our natural and manmade assets is not made within the next decade. The water industry requires adaptation of infrastructure to ensure that water supplies for urban consumption, agriculture and industry demands are secured under a growing population, given changes in the climate and considering a rise in demand from China over that time.

There are many more megatrends to absorb and I encourage you to stop and think about how they will influence the way the water industry will operate over time, and how Young Water Professionals can play a role in ensuring the strength of our industry for decades to come.

When you put these challenges into perspective, you will realise there is no better place to make a difference than in the water sector.

10-12 May 2016 Melbourne Convention and Exhibition Centre

Australia’s international water conference & exhibition

TRADE EXHIBITION OPPORTUNITY The Ozwater’16 Trade Exhibition is the largest display of the latest water industry science, innovation, technology, products and services for all water professionals and associated industries.

This Trade Exhibition gives exhibitors access to the biggest annual gathering of Australian water industry personnel.

WHY EXHIBIT?

WHO WILL ATTEND?

Immerse your prospective clients in an encompassing experience that delivers your marketing message in a powerful way.

• • • • • • • • • • • •

Virtually all marketing goals can be achieved concurrently at this exhibition.

Some of the potential results of exhibiting at Ozwater’16 will be: • • • • • • • • • •

Attracting targeted buyers Long term brand building Brand awareness Generating media coverage Collecting highly qualified leads Relationship building within the industry Appealing to decision makers Immediate sales Launching new products Entertaining loyal and prospective customers • Researching the market • Educating prospective customers

Manufacturers Water Utilities and Retailers Water Professionals Government Educators / Academics Consultants Media Purchasing Officers Engineers Contractors Regulators Community Groups ... and many more!

BOOK YOUR SPACE NOW Stephen Comey Senior Exhibition Manager Australian Water Association Phone: 02 9467 8406 Email: scomey@awa.asn.au

www.ozwater.org

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AWA News

ASIAN MARKET OPPORTUNITIES: JOIN THE DELEGATION TO VIETWATER Are you looking to expand your business into Asia? The Australian Water Association and the Vietnam Water and Wastewater Association, in partnership with the Department of Foreign Affairs and Trade, Austrade and ANZ, invite you to participate in the Australian delegation to VietWater, Vietnam’s number one international water and wastewater industry event which attracts over 10,000 visitors from across 35 countries.

The event takes place 25–27 November 2015. The cost for participation is $2,500 (ex GST) and delegate registrations are due by 3 September 2015. To register please visit www.awa.asn.au/ vietwater2015 or for more information please contact Paul Smith, International Manager, on 02 9467 8403 or psmith@awa.asn.au

HATCH YOUR EGG ...

WITH THE INNOVATION INCUBATOR PROGRAMME We’re looking for the innovators of the water sector who are ready to hatch their idea through our Innovator Incubator Programme. The program is a 12-month schedule of activities that will facilitate and accelerate the market entry and adoption of your water or wastewater management technology. The programme has been designed to give you exclusive access to the most relevant and influential industry representatives and investors through tailored B2B meetings and pitching opportunities aligned with Australia’s major water events such as Ozwater and the Water Innovation Forum.

To discuss your innovation or learn more about the programme please contact Jerome Moulin, Industry Innovation Programme Manager at the Australian Water Association, on 02 9467 8436 or jmoulin@awa.asn.au

REGISTER YOUR INTEREST FOR EXCHANGE AND TWINNING IN ASIA The Australian Water Association is seeking expressions of interest from high-performing water utilities and government agencies to participate in the International Exchange and Twinning Program in Vietnam, Thailand, Indonesia and India. Twinning offers a range of benefits including: • Unique staff development opportunities; • Achievement of corporate social responsibility goals; • National and international networking and contacts; • Profile raising; • Gaining international perspectives on water.

water AUGUST 2015

Under a twinning arrangement, the Australian Water Association will facilitate logistical and funding support for international travel and accommodation costs. Such a twinning arrangement would involve a work plan that runs for 12–18 months. The work plan would be project based and focus on one area such as non-revenue water, asset management, water quality, sanitation, pricing or governance.

Within the work plan are exchange visits at critical stages of the partnership. The resource requirement would typically be between 50–80 person days over an 18-month period.

For more information please contact Paul Smith, International Manager, on 02 9467 8403 or psmith@awa.asn.au

BRANCH NEWS QUEENSLAND Queensland YWP Election & Events The Queensland Young Water Professionals elections were conducted recently. As Committee roles changed, it was an ideal time to reflect on the Committee’s achievements during the past 12 months under the presidency of Charlotte Spliethoff and Sarah Schroeder (who took maternity leave earlier in 2014). These achievements included the first ever Amazing Race, a Networking Event which was attended by 60 YWPs and the launch of the Professional Development Program.

Around this time last year, the Queensland YWPs were up for a great cause, giving a presentation and practical exercise at the Brisbane Youth Education and Training Centre. The Committee participated in multiple university career events and presented at the senior management forum of the Department of Energy and Water Supply (DEWS).

The new Committee’s first event in July included the YWP presenting in front of 250 third-year engineering students from the Queensland University of Technology (QUT) who are studying Water and Wastewater Engineering. In October, the Amazing Race will occur for the second time and the water industry will come together in a competitive environment.

Companies will form teams and compete in an afternoon of mental and physical challenges in an attempt to remove SEQwater’s possession of the famous Amazing Race trophy. Will it be your company that proudly displays this trophy in their reception area for the next 12 months?

The Committee would like to thank leaving Committee members Anne Cleary, Betty Alegria, Hannah Shaw, Jessica Roffey, Justin Simonis and Sarah Schroeder for their great commitment, and is delighted to welcome three new members – Thakshila Balasuriya, Matt Sorenson (Secretary) and Alex Wise. The Committee is pleased to have Abraham Negaresh, Alycia Moore, Charlotte Spliethoff, Christina Lockett, Ehsan Eftekhari, Elena Mejia Likosova, Robert Goedecke and Rui Pu Yang as continuing members, and looks forward to another exciting 12 months of teamwork and providing value to YWPs.

WESTERN AUSTRALIA WA Branch and YWP Committee Elections The WA Branch has successfully completed the nomination and election of the new WA Branch and YWP Committees. Welcome to returning members Peter McCafferty, Deanne McDonald,

NEW! Garth Walter, Barry Sanders, Daniela Tonon, Tara Zirakbash, Steve Jamieson and Jesus Ortiz, and new members Cristiano Carvalho, Don Crawford, Stefan Davidov, Rachel Evans, Ursula Kretzer, Noel Lavery and Fabiana Tessele to the WA Branch Committee.

The new YWP Committee includes returning and new members, Carol Matasci, Halinka Lamparski, Kruti Patel, Adam Kaye, Arpitha Babu, Vivien Claughton, Shuo Pan, Claire Horsley, Claire McGowan and Renee Blandin. Thanks to outgoing committee members Denis Ericson, Des Lord, Oana Lord, Peter Addison, Vince Cinanni, Anna Cortier, Cory Fletcher, Michael Gillen, Nisarg Shah, Kate Bowker, Satinderpal Sidhu and Tung Nguyen for their valuable contributions over the years.

Upcoming Events Key upcoming events include the WA Annual Water Conference, which will be held on 23 October at Mandurah Quay Resort. The focus of this year’s conference will be Water Innovation.

The WA Water Gala Dinner and Awards Ceremony will be held on 20 November at the Duxton Hotel, Perth. More information will be available when registrations open. Please check the Australian Water Association website for more details on these and other events.

YWP Mentoring Program The WA Young Water Professionals are launching their Mentoring Program on 3 September. The Program is aimed at supporting young professionals in the water sector to develop their career.

Registrations for mentees and mentors are still open and available on the website.

TASMANIA New Tasmanian State President Tim Gardner, Executive Chairman, Stornoway has been appointed as the Tasmanian State President of the Australia Water Association.

Tim outlines his vision for the Association here.

“It is a very exciting time for the Tasmanian water industry with unprecedented investment in water infrastructure, both municipal and agricultural, along with a growing global recognition of Tasmania as a premium tourism destination and food bowl, both of which rely heavily on clean water to sustain their reputation.

“The State also continues to grow as the hub for Southern Ocean research, as well as the key staging point for the Antarctic. With this in mind, I would like to see the Australian Water Association raise its profile in the public debate about the future of water on and around the state, facilitating discussion that draws upon a wide range of scientific, technical and operational knowledge to support informed decision making.

“In firming up our direction for the coming years, we will be drawing upon the business strategy and resources of the Association nationally as they apply to Tasmania, as well as gaining feedback from our state membership as to your priorities.

“I’m looking forward to being able to build on the good work done by the outgoing Executive and to further develop the Association as the peak representative body for the water industry in Tasmania.”

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22

AWA News

New Members AWA welcomes the following new members since the most recent issue of Water Journal.

NEW CORPORATE MEMBERS

NEW INDIVIDUAL MEMBERS

NEW SOUTH WALES

AUSTRALIAN CAPITAL TERRITORY P Fiddes, J Green, D Spackman

Corporate Silver

NEW SOUTH WALES

BAI

M Gerber, S Gillespie, G Hall, R Santangelo, M Alvaro, D Stalker, M Gould, D Lynch, J Cole, M Cox, S Le Poidevin, T Thomson, M McNaughton, T Vourtsanis, E Parry, J Murray, J Osborne, M Smith

Corporate Bronze IDEXX Laboratories

QUEENSLAND Corporate Bronze

TASMANIA L Bishop

VICTORIA K Corbett, J Thurtell, J Wardle, N Carracher, C Newton, N Gosavi, M McJannet, I Brookman, H Clamp, B Lewis, R Cockerton, R Chandra, C Johnston, S Dwyer, R Keeble, A Bagchi, S Han, D Myers, C Gill, S Dutta, S Chandra, C McClusky, G Kingsbury, S Ng, Y Collins

WESTERN AUSTRALIA

Practical Engineering Australia Pty Ltd T&C Services Pty Ltd

NORTHERN TERRITORY

VICTORIA

QUEENSLAND

M Rowe, E Arnold, R Ferritto, A-E Buma, R Blandin de Chalain, K Cracknell, S Delides, U Kretzer, V Claughton, H Merrett

SOUTH AUSTRALIA

NEW OVERSEAS MEMBERS

D Moliere, R Garstone, J Ellis, E Lawson E Gosse, N Kruger, L Kearins, N Hewison, C Hurley, L Lynch, J Long, A King, P O’Kane, R Crozier, A Cleary, L Cook

Corporate Platinum Thiess Services Pty Ltd

OVERSEAS Corporate Silver

G Combeer, S Bondarenko, L Johnston, B Rea

Sensus, United Kingdom

B Manning, New Zealand; M Wilson, United Kingdom

AWA EVENTS CALENDAR This list is correct at the time of printing. For up-to-date listings and booking information please check the AWA online events calendar at: www.awa.asn.au/events

August Tues, 18 Aug

VIC: Technical Event, Drinking Water Guidelines, Melbourne

Thurs, 20 Aug

TAS: TWEMA 2015 Presentation, Wrest Point Convention Centre, Hobart

Thurs, 20 Aug

TAS: Where the Waters Meet Conference, Hobart

Thurs, 20 Aug

ACT: Student/YWP Careers Night, Canberra

Wed, 26 Aug

QLD: Breakfast – Seqwater Water Security Plan, Brisbane

Thurs, 27 Aug

SA: Technical Event, Theme TBA, Adelaide

September Thurs, 3 Sept

WA: YWP Speed Mentoring Event, Perth

Wed, 9 Sept

VIC: Evening Seminar – ‘Climate Change’, with Minister Neville, Melbourne

Thurs, 10 Sept

ACT: Water Leaders Dinner, Old Parliament House, Canberra

Thurs, 10 Sept

VIC: YWP Essential Skills Workshop: Straight Talk, Melbourne

Fri, 11 Sept

NSW: Women in Water Event, Newcastle

Thurs, 16 Sept

National: Ozwater’15 Highlights Event, Perth

Thurs, 16 Sept

NSW: Technical Event: Theme TBA, Sydney

Fri, 18 Sept

QLD: Gala Dinner & Awards Night, Brisbane

Wed, 30 Sept

QLD: YWP Event, Brisbane

water AUGUST 2015

international

CALIFORNIA DREAMIN’ ... OF COOL, CLEAR WATER After four years of drought the California Government is taking steps to reduce water consumption and improve water efficiency.

The Australian Water Association recently hosted a delegation to the ACE15 conference in Anaheim, California, providing an ideal opportunity to showcase Australia’s water efficiency technology. National Manager Industry Development, Geoff Gray, reports.

A leading commentator on the California drought said: “It is time to give up on hope, hope it will snow, hope it will rain and hope the rivers will flow again”.

Drought-stricken California has a much-reduced snowpack this year compared to 2010, its last near-normal year. Because snow is the major source of precipitation in California, less snowpack means less snow to melt and refill the state’s reservoirs.

The snow and rain will return – and maybe sooner than expected as the deepening El Niño in the Northern Pacific is one of the strongest in years. It should bring precipitation to California next winter. However, relying solely on that to happen is too great a risk for any government to take, particularly in one of the world’s largest and wealthiest economic regions. Californians scratch their heads: “We have Apple [the world’s richest company], Silicon Valley, Stanford University, Hollywood, freeways and a leading aerospace industry, but we do not have enough water”.

23

AWA News WATER WARS The California drought can be seen as something of a north-south issue, although not quite another Civil War. The southern part of the state is where most people prefer to live, in the lovely sunny weather where the annual rainfall is only around 25mm, most of which falls in the winter. You can plan a garden party in Los Angeles in any day in July and know it will not rain.

The north of the state has large redwood forests, beautiful lakes, fast-flowing rivers and world-class wine growing regions. San Francisco is in a similar latitude north as Melbourne is south, and has a more reliable rainfall and a heavy snowpack in the Sierra Nevada Mountains. It is in the north where the drought is really biting hard, and the northern water districts have higher mandated targets for reduction of water consumption. This has not gone down well, as they see the south taking a lot of their water; they feel they now need that water.

The drought is having other severe consequences in the north, not just water shortages. The land is subsiding, particularly in the lower reaches of the San Francisco Bay region, which is Silicon Valley. Among others, high-tech company Oracle, with over 5,000 employees at their main office, is now well below sea level and still falling as groundwater levels drop. A tsunami or earthquake, which is always possible, could swamp many of the world’s leading companies. There is little that can be done in the short term; water is still being pumped out to meet current demands, and even at reduced rates the demand is unsustainable and there is no alternative water supply.

Urban water requirements for the big coastal population centres of the state are significant – nine million in the San Francisco Bay area, 14 million in Southern California and five million in San Diego; all need to import water supplies. However, even their total requirement is a very small fraction of the water used in the agricultural sector in the inland valleys.

The Government can no longer rely on advertising campaigns with movie stars, funding programs to replace lawns and imposing higher water rates. The California Government in April this year set mandatory water reduction targets of around 25 per cent for each water district, and they will face heavy fines if they do not reach those mandated targets by the end of the year.

Californian water regulators later revised the drought plan by easing cuts for Los Angeles and San Diego and bumping up reduction targets in the areas that consume the most water, primarily in the north of the state where water is usually readily available and there has been little effort so far to reduce consumption.

Photo: Oracle

MANDATORY RESTRICTIONS California is not only a leading high-tech and service economy – it is also the number one agricultural producing state in the US. The central valley is the major supplier of fruit and vegetables to the whole of the US, relying heavily on irrigation from unregulated groundwater supplies. Australia’s imported produce from the US, including grapes, cherries, oranges and stone fruits, all come from California.

The Oracle building is gradually sinking as the land it is built on subsides.

The drought is hitting hard in the drier valleys and high desert areas. Some towns have completely run out of drinking water and supplies have to be trucked in at a considerable cost. Many resort towns, with lovely golf courses, artificial lakes, green lawns and large retirement communities have been built in desert regions, where they have relied on ample groundwater.

Owners of property can pump as much water as they like; they even have the rights to the oil and minerals under their land. In fact, a number of communities in California became very wealthy as they found oil, as well as water, which is what they were actually looking for. Many of these towns and resorts have been pumping water at unsustainable rates for up to 100 years and have sucked out water that had accumulated over thousands of years. Now they are stuck.

The wells are deep and pumping mud; they are too far away for an economic pipeline to be laid and too large in scale for trucking water. Some of these communities will have to make drastic changes to their lifestyle, such as substituting cactus gardens for green grass, or they could become ghost towns, a little like what we used to see in old Western movies, saltbush blowing down the deserted streets.

AUGUST 2015 water

24

AWA News With the country's most populous state well into this devastating drought, Governor Jerry Brown has ordered cuts in urban water use through the first state-wide mandatory reductions in California’s history.

“We're not at the point where we can set a single target for everywhere in California, because climates are so different and because we're in an emergency,” Felicia Marcus, chair of the State Water Resources Control Board, said recently in a conference call with reporters.

Brown has said cities that already use less water than others would have to make relatively smaller cuts, while those with higher per-capita use are facing more stringent targets. Generally the southern cities use more water per capita, for their swimming pools and green lawns, but they have done a better job in already making cuts, so the biggest cuts will be in the north of the state.

The original plan divided local water agencies into four tiers, imposing a 10 per cent conservation standard on those that use less water per capita and a 35 per cent standard on those that use the most. The current plan doubles the number of tiers. Regulators said the additional categories would mean agencies with similar levels of consumption would not fall into tiers with vastly different curtailment standards.

Los Angeles and San Diego, the state's No. 1 and No. 2 cities respectively in population, would each find themselves in a tier with a mandatory curtailment of 16 per cent under the revised plan, compared to 20 per cent in the tier they would have fallen under in the previous plan. The suppliers with the highest per capita water use would have to accept a 36 per cent cut, up from 35 per cent.

The Water Board will fine water utilities up to $10,000 per day if they fail to persuade residents and businesses to make cuts.

Meanwhile, environmentalists and some urban dwellers say the state’s $45 billion agriculture industry should bear a greater share of water savings, given its massive water use. But Marcus defended the industry, saying farmers have already "taken very severe cuts".

water AUGUST 2015

international AN INNOCENT-LOOKING VILLAIN They are said to be good for you and are certainly delicious, but the unassuming almond is being cast as a villain. Visitors to California’s Central Valley, home to some of the most fertile farmland on the planet, are met each spring by seemingly endless fields of almond blossom, the trees seemingly covered in a pale pink frost. Vast, cathedral-sized mountains of almond shells sit next to processing plants.

Such sights attest to the part almonds play in the local economy: California produces 80 per cent of the world’s crop, worth nearly $US5 billion a year.

The designation of almonds as a heart-friendly superfood has boosted consumption, while almond milk is being embraced as a dairy substitute. California’s farmers have ripped out tomatoes, melons and other crops, as they scramble to profit from the almond rush. There is, however, a problem: to produce just one single almond requires about a gallon of water, a resource now in chronically short supply.

This year, for the first time, Californian households have faced mandatory water cuts: lawns are turning brown; restaurants are outlawed from offering diners glasses of water, and hotels face strict rules on when they do laundry.

Yet according to Tom Stokely, an analyst with the California Water Impact Network, an activist group, during the past three years of drought some 150,000 acres of almond trees have been planted – enough to use nearly as much water as the city of Los Angeles. All told, almonds consume more water than all of the indoor residential use in all of California, he adds. Yet almond farmers have so far escaped water controls.

Almond production is growing rapidly in Australia and we will soon be the biggest producer outside of California. In Australia, the industry relies on water trading and buys the water it needs to develop the industry. Almonds are commanding a high price and growers can afford to bid up prices for their water needs. In dry times we are not growing as much rice, but the almond plantations prosper.

international

25

AWA News

The California agricultural sector accounts for about two per cent of the state’s economy but uses 80 per cent of California’s water. Farmers are not oblivious: a group with some of the strongest water consumption rights in California has offered to voluntarily cut their use by 25 per cent.

Governor Jerry Brown’s emergency water conservation measures will also impact California’s colleges and universities, which in many ways operate as independent cities; they face a strong challenge meeting those mandates. The water footprint of the state’s higher education system is substantial: there are 10 University of California campuses, 23 California State University campuses, and 112 California Community Colleges.

Many of these campuses feature lush tree-lined pathways, vast areas of carefully cultivated gardens and shrubbery, and, of course, plenty of thirsty turf grass. Beyond that, each campus is a virtual city that consumes water in residence and dining halls, research laboratories and general operations.

Yet the university system is putting in place a number of measures to conserve water to help municipalities meet the mandates and adapt to this prolonged drought.

THE ANAHEIM CONVENTION The American Water Works Association, the nation’s leading drinking water association, held its Annual Convention and Exhibition in Anaheim, California (right next to Disneyland) on 8–10 June. As you would expect, many of the technical papers and workshops focused on issues around the drought.

Interestingly, during the same month as the ACE15, there was severe flooding in the middle of the US after record snowfalls in the east during winter. Although the west is in drought, May and June were the wettest months ever recorded in the US. The Australian Water Association had a stand at the ACE15 exhibition utilising space provided to the organisation under a cooperative agreement with the AWWA. During this year’s congress the AWWA and the Australian Water Association signed a formal Joint Cooperation agreement to work together to better assist the water sector in both countries.

Like the Australian Water Association, the AWWA is expanding its international programs and assisting their members to seek out new opportunities in rapidly growing economies. The Americans have established a branch of the AWWA in India and opened an office in Mumbai.

The International Lounge at the ACE15 Exhibition. extensive exhibition, which was visited by some 11,000 visitors.

The Australian team hosted a workshop in the exhibition on water efficiency and a number of Australians presented papers at the congress and participated in workshops.

The Californians are very impressed with our water efficiency and the gains made during the Millennium drought. The per capita consumption levels in California are still way above the levels reached in Australia. In Los Angeles many consumers show little regard for water-saving measures; there seems to be no shame in watering the lawn every day to keep it to the desired shade of green. The Australian Consul General in Los Angeles was keen for the landlord of the Consul residence to replace the large lawn with a water-saving surface. The landlord could not understand why they should do that, particularly as they are in the fine western suburbs of the city. Drought in California does seem to be class related, with less concern among some of the wealthier and famous in society.

Another California delegation will be visiting Australia in October to further discuss water efficiency, water trading and recycling. A number of Australian companies and researchers have won commissions to help develop water strategies and improvement in governance.

The Australian Stand featured Australian expertise in processing greywater, desalination, pipe maintenance, water efficiency and a range of consulting expertise. The stand was located in the

Our participation in California was rewarding and further enhances the close relationship between the water sector in our two countries. There’s no doubt that they appreciate our contribution; unfortunately, however, we cannot make it rain or snow for them.

Steve Simmons, Director, Detection Services and Derek Ephrem, Austrade, San Francisco.

Doug Ryerson, Hydrosmart, David Thorn, Wise Water Solutions, SallyAnne Bartlett, Water Q Plus, and Brett Kelly, AWMA Water Control, at the AWA stand.

AUGUST 2015 water

feature article

water markets & trading

27

Feature Article

CHANGING SUPPLY AND DEMAND FOR WATER IN THE SOUTHERN MDB AND THE IMPACT ON WATER MARKET PRICES An analytical feature by Louise Barth, Ryan Gormly and Chris Olszak

W

ater markets in Australia have developed substantially over the past two decades. They are now an established part of agricultural, urban and environmental water policy and management in Australia. Australian water markets are helping balance competing demands for Australia’s scarce water resources and delivering more efficient water investment, allocation and use. They provide business flexibility and risk management benefits, and help deliver important public policy outcomes. They are also increasingly viewed as an attractive opportunity for investors.

Since 2010–11, the supply and demand for water in the southern Murray-Darling Basin (MDB) has shifted significantly, corresponding to continued increases in water entitlement and allocation market prices. Drier climatic conditions are the primary driver. However, there are a number of other possible drivers behind these recent movements, including the Commonwealth’s purchase of water entitlements for the environment, which has reduced the supply of water available for consumptive irrigation use and increased demand for the production of cotton, almonds and other nuts.

The hypothesis explored in this article is that recent increases in water allocation and entitlement prices not only reflect recent drying climatic conditions, but also changes in underlying supply and demand side factors.

Market fundamentals Australia’s water markets comprise two distinct but related entities – the entitlement market and the allocation market. Water entitlements are ongoing rights to receive a share of available water resources in a consumptive pool. Each catchment typically has a small number of entitlement types or ‘classes’, and generally all entitlements within a given class are homogenous. Water allocations are the volumes of water allocated to water entitlement holders during the water year (1 July to 30 June). They are a physical good analogous to a commodity, and are extracted from water courses and applied as inputs to production or the environment. Their value per unit varies within, and between, years. There is no single national market for these products, but rather a number of individual separate markets. Where hydrological connectivity exists, such as in the southern connected Murray-Darling Basin, trade between these markets is possible.

Several factors influence supply and demand (and, therefore, prices) within water entitlement and allocation markets. The amount of water allocated to entitlement holders each year is a key driver of allocation market outcomes (including prices and volumes traded), because it strongly influences the total amount of water available for use or trade.

When allocations are low, water is scarce and prices are high, and the opposite is true when allocations are high. The inverse relationship between seasonal allocations and prices described above is represented in Figure 1, where allocation prices have increased annually from a low in 2011–12, as total water allocated has been decreasing.

Figure 1. Total water availability and price, major southern MDB products and zones.

(Source: New South Wales Water Register 2015, South Australian Water Register 2015 and Victorian Water Register 2015)

AUGUST 2015 water

28

Feature Article

Murray-Darling Rainfall Deciles

1 July 2010 to 30 June 2011

Murray-Darling Rainfall Deciles

Distribution Based on Gridded Data Product of the National Climate Centre

1 July 2014 to 30 June 2015

Distribution Based on Gridded Data Australian Bureau of Meteorology Rockhampton

Longreach

Bundaberg Birdsville Charleville

Rainfall Decile Ranges Highest on Record 10

Rainfall Decile Ranges BRISBANE

Oodnadatta

Very Much Above Average Marree

8-9

Above Average

4-7

Average

2-3

Below Average

1

Very Much Below Average

Grafton Bourke

Tamworth

Dubbo

Pt. Augusta

Highest on Record 10

Very Much Above Average

8-9

Above Average

4-7

Average

2-3

Below Average

1 SYDNEY

Mildura

Lowest on Record

Wollongong ADELAIDE

Very Much Below Average Lowest on Record

CANB Albury Horsham

Bega MELB

Portland

Sale

Figure 2. Murray-Darling Basin rainfall deciles, 2010–11 and 2014–15. (Source: Bureau of Meteorology, 2015) Allocation levels reflect water availability, including rainfall and inflows in relevant catchments, and volumes held in storages.

Key demand drivers within the allocation market include the amount of different crops planted, market conditions for irrigated agricultural products and conditions within substitute input markets.

The availability of carryover, whereby entitlement holders are permitted to carry over unused allocations from one year to the next, can also influence the extent of allocation trading.

heavy rainfall which saw seasonal allocations increase significantly to almost 7,000,000 ML and prices decline to around $20/ML across the southern MDB (see Figure 1). As shown in Figure 2, drier conditions have returned more recently, which has led to a reduction in water availability. The trend has resulted in an upswing in allocation prices, with corresponding upward pressure on entitlement prices.

While allocation trading is driven by seasonal conditions and other short-term changes in demand, water entitlement trading is generally driven by changes in long-term demand and in the nature of irrigated industries. Entitlements can be purchased as an investment or risk management tool, and entitlement trading may also reflect shifts between agricultural sectors, or participants exiting from irrigated agriculture.

Since 2007–08, the Commonwealth Government has purchased entitlements in the MDB for environmental purposes. While there has been limited additional entitlements purchased from 2011–12 to 2014– 15, ongoing environmental use of allocations to these entitlements has affected the supply of available water for consumptive use. Much of the environmental entitlement is held by the Commonwealth Environmental Water Holder (CEWH), which, within the major southern MDB systems currently holds approximately 1,094 GL (Department of the Environment 2015)1. As shown in Figure 3, the proportion of water allocated to these entitlements has increased over the past six years to 16 per cent of total water available. For 2014–15, water allocated to entitlements purchased by the Commonwealth has reduced the volume of water available for consumptive use by approximately 870,000 ML (from 5,394,000 ML to 4,519,000 ML).

Trade in entitlements is related to longer-term investment and adjustment decisions and the characteristics of different irrigated agricultural enterprises, including their tolerance for risk. In contrast to the trade of allocations, prevailing climatic conditions have a more muted impact on entitlement trade. Producers, who may be expanding or contracting production, drive market activity.

Investors are also seeing the opportunity to enter the market for entitlements and to trade allocations in order to generate a financial return. Ultimately, however, the value of entitlements in the market should reflect the expected future value of allocations to those entitlements, based on their underlying reliability characteristics and demand-side drivers.

In addition to seasonal conditions, water prices, storages and commodity production, changes in the way markets are governed, and how information is provided and received influence trading patterns.

Drying climatic conditions over the last three years On the supply side, water availability has fluctuated considerably over the past decade due to the significant variability in rainfall and climatic conditions over that period. South-Eastern Australia experienced severe drought conditions during the Millennium Drought of the 2000s. During this period, allocations to water entitlements were low, which corresponded to very high allocation prices. In 2010, the onset of La Niña conditions resulted in very 1

Water purchases by Government for the environment

Changing demand factors During periods of low water availability when allocation prices are relatively high, lower value crops such as rice will typically not be grown, as illustrated by the sharp decline in water use for rice production from 2005–06 to 2009–10 (Figure 4). However, higher value crops with fixed water demands like nuts need to be provided with water every year.

Figure 4 shows that against this backdrop of reduced water availability for consumptive use, the demand for water has also changed over time. High value commodities such as fruit and nuts with fixed demands have generally had comparatively static water use over time, but clearly increased their consumption of water in 2012–13. While water use on crops with more variable demands such as rice and summer crops has declined since the early 2000s in response to lower water availability, dairy (and hay, which is typically an input to dairy) has also varied its use substantially in response to prices and water availability.

ntitlement products purchased by the Commonwealth presented in the aggregate here include NSW Murray High Security and General Security, E Murrumbidgee High Security and General Security, Vic Murray High Reliability, Goulburn High Reliability, and SA Murray. Annual environmental holdings associated with buyback were sourced from National Water Commission markets reports and the Australian Government.

water AUGUST 2015

water markets & trading

Figure 3. Water allocated to Commonwealth purchased entitlements relative to total water availability in the southern MDB. (Source: NWC 2013, New South Wales Water Register 2015, South Australian Water Register 2015 and Victorian Water Register 2015) Growth in demand from higher value crops such as cotton has also occurred, as cotton producers have commenced planting in the southern MDB. Cotton producers have a higher willingness to pay for water relative to most annual crops, as certain output volumes are required each year to ensure viability. Therefore, water use for cotton production has displaced water used in the rice industry in the southern MDB, relative to 2000–01. The Murrumbidgee region in particular has experienced a sharp rise in cotton production in recent years, which has traditionally not been grown in the area.

The transition to cotton production has been driven by the higher relative profitability compared to rice and the emergence of coldtolerant cotton varieties. It has also been facilitated by investment in three new cotton gins within the region.

The production of fruit and nuts has also strengthened over the period in response to heightened consumer demand for almonds, walnuts and hazelnuts. New developments of almonds and other nuts in the major growing regions of Sunraysia and Riverland have increased the demand for water in those areas. The almond industry in particular is one of Australia’s fastest-growing horticultural sectors.

There has been a recent trend for investment in new plantings by development investment companies and growers looking to exit unprofitable horticultural crops, driven by higher world almond prices, the drought in California (a major almond-growing region), and the lower Australian dollar. Due to the hot, dry climatic conditions experienced within the major nut-growing regions, there are no alternatives to irrigation. As almonds and other nuts have relatively fixed water demands in order to optimise fruit and tree growth, the investment has resulted in an increase in water use for nut trees within the southern MDB from 366 GL in 2005–06 to 540 GL in 2012–132 (Figure 4).

While the demand for water has increased among cotton and fruit and nut producers, the dairy industry has reduced their water use since 2005–06 in response to lower water availability and difficult market conditions, and bulk wine grape producers have struggled with low commodity prices (however, prices are now possibly starting to rebound). Unlike the horticultural industry, which has fixed water demands, dairy farmers can respond to lower water availability by purchasing feed or moving cattle for agistment elsewhere, although this may be costly. While the dairy industry remains the third largest contributor to irrigated agricultural production in the MDB and improved seasonal conditions since the drought have boosted production since 2009–10, the industry is significantly exposed to global commodity market conditions, which in recent years have affected 2

29

Feature Article

Figure 4. Water use by commodity in the southern MDB, 2000–01 to 2012–13. (Source: ABS 2014, New South Wales Water Register 2015, South Australian Water Register 2015 and Victorian Water Register 2015) the profitability of the sector. Water use efficiency improvements in the dairy industry have also been made through initiatives by the Commonwealth and State Governments as well as individual farmers, which are likely to have influenced the industry’s demand for water.

Observed results in the water market Within this context of shifting supply and demand for water, allocation and entitlement markets within the southern MDB have experienced marked changes since 2010–11. As the demand for water has increased against a backdrop of lower water availability, the allocation price in the southern MDB has grown considerably in recent years, to an average price of $120/ML in 2014–15 (Figure 1). Water allocation trading generally helps water users respond to seasonal conditions and other short-term events by reallocating water among them within a particular year. The increase in allocation price reflects the drier seasonal conditions and expectations regarding the poor rainfall outlook, which has led irrigators to enter the market to purchase additional allocations for use within the year or potentially for carryover. Further, recent evidence from consultation with water market intermediaries suggests that allocation prices through June and July 2015 have been considerably higher than the prices reported in the state water registers and presented in Figure 1. Opening prices in 2015–16 have increased to between $180 and $200 per ML in the southern MDB. As shown in Figure 5, prices for high reliability entitlements in the major southern MDB systems gradually declined from 2010–11 in the early years of the decade as rainfall and water availability improved, the global financial crisis affected the outlook for agricultural commodities, and the Commonwealth reduced its purchasing activity in the market.

However, since 2013–14 entitlement prices across the southern MDB have experienced a rapid resurgence. Changes in the agricultural production mix and other demand-side drivers discussed previously may have also contributed to the recent upswing in entitlement prices, as well as the continued increase in allocation prices that would place upward pressure on entitlement prices as investors pursue higher yields. Water market intermediaries have indicated that current market prices for entitlements are considerably higher than those suggested in the register data presented in Figure 5 for 2014–15. Estimates from brokers indicate that Victorian entitlement prices increased by 20 per cent in the final quarter of 2014–15, with prices of around $2,300/ML for high reliability entitlements in the Greater Goulburn system.

Australian Bureau of Statistics 2014.

AUGUST 2015 water

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Feature article

Note: Entitlement trades for 2015–16 only include data for July 2015, and trades have only been registered in the Vic 7 Murray and Vic 1A Greater Goulburn systems to date.

Figure 5. Entitlement prices, major southern MDB systems, 2010–11 to July 2015–16.

(Source: New South Wales Water Register 2015, South Australian Water Register 2015 and Victorian Water Register 2015)

conclusion and future outlook

social and environmental value of water and they facilitate

It is clear that shifts in the demand and supply of water have been occurring due to a number of factors, including the allocation of water to government-held entitlements, and changes in the types of commodities produced by irrigators. There is evidence to suggest that these changes in supply and demand have exacerbated the increased pressure on water entitlement and allocation prices driven by expectations of lower water availability. The increased production of higher value commodities such as cotton and nuts in the southern MDB has corresponded with heightened water demand, which has placed increased pressure on water allocation prices. In turn, water entitlement prices have also recovered in the past year following a period of decline.

adjustment and development in an efficient and effective manner.

Looking forward, the combination of predicted dry climatic conditions and fundamental shifts in demand is likely to translate into continued pressure on allocation prices, at least in the short to medium term. Depending on the extent to which expectations regarding these trends have been factored into entitlement prices, this could also result in a rise in entitlement prices, as financial yields increase and irrigators attempt to mitigate allocation price risks by securing more entitlements for new crop plantings.

Rising water prices can be difficult for some irrigators as they result in a movement of water away from production in some industries like rice and dairy. However, if left to operate efficiently, water markets will continue to deliver benefits to individual irrigators, industries and communities. Trading of water provides financial benefits to sellers and enables buyers to continue to water high value crops, particularly long-lived horticultural assets.

As the National Water Commission found during the Millennium drought, markets contribute to the goal of optimising the economic,

water AUGUST 2015

Many international jurisdictions including California and the United Kingdom are looking to the market-driven model in Australia as the best approach to manage scarcity. WJ

the authors Louise Barth (email: louise.barth@aither.com. au) is an economist with experience in policy development, economic analysis, modelling and forecasting. Louise is a Senior Consultant at Aither, based in Melbourne, and has specific expertise in water market analysis and the development of bespoke water market and supply-demand models.

Ryan Gormly (email: ryan.gormly@aither. com.au) is an economist and policy analyst specialising in water, the environment and resources. Ryan is a Principal Consultant at Aither, based in Canberra and was previously a Senior Manager at the National Water Commission.

Chris Olszak (email: chris.olszak@aither. com.au) is an economist who specialises in public policy, economic appraisal, pricing and regulation, and market analysis. He co-founded Aither in 2012 after previously working with Frontier Economics, URS and Arthur Andersen.

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32

Feature Article

DROUGHT AND WATER MARKETS: HOW ALLOCATION WATER MARKETS CAN SUPPORT PRODUCTION AND ENVIRONMENTAL OUTCOMES Rod Carr from Marsden Jacob outlines the evolution and recent developments in Australia’s allocation water markets.

D

emand for water is increasing globally for a range of reasons, including growing populations, demand for food and textiles, and understanding of the uncertainty around our water supplies.

Critically, the water availability outlook for much of rural Australia is poor. The water year has recently opened with low allocations across much of New South Wales and Victoria and the Bureau of Meteorology has announced that an El Niño has formed.

Water markets have been embraced for their ability to increase flexibility and risk management for irrigators, communities and environmental water managers. Water markets are also increasingly being used by corporate investors to diversify their asset mix.

The Australian water market is composed of several separate water markets, differentiated by water system or administrative boundaries. The scale of Australia’s water markets varies greatly, from small, unconnected water markets to extensive connected systems in the Murray-Darling Basin (MDB), the largest water trading area in Australia.

The MDB is typically split into two distinct regions: the southern MDB and the northern MDB. The majority of waterways of the southern MDB are hydrologically connected, which permits water trading across nearly the entire region. The northern MDB consists of distinct waterways and groundwater sources that are far less connected.

As a result, trading tends to occur only within, rather than across, catchments in the northern basin (see Figure 2 and Figure 3).

what are TRADEABLE WATER PRODUCTS? There are three broad types of tradeable water rights: • Water access rights; Figure 1. El Niño Southern Oscillation Index (ENSO) tracker.

(Source: Bureau of Meteorology, 7 July 2015)

• Water delivery rights; and

In this article we discuss the evolution of, and recent developments in, Australian water markets. We will focus particularly on allocation markets, because it is likely that this market is going to be tested in the near term by low water availability – and it is a critical market during low water availability periods because it is a key source of water for crops, livestock and environmental water users.

There are also four sub-categories of water access rights (see Table 1).

AUSTRALIA’S WATER MARKETS Australia was an early adopter of water markets, because by the early 1980s it was clear that the health of many river systems was in decline and many water resources were fully or over-allocated.

The 1994 COAG Water Reform Framework aimed to address this over-allocation. A key action under this intergovernmental agreement was the separation of land and water property rights so that water could be traded separately from land.

Today, Australia leads the world in the development of water markets, and they are an established part of Australia’s rural landscape, especially in the Murray-Darling Basin.

water AUGUST 2015

• Irrigation rights.

Additionally, there are a number of derivative-like products that are increasingly traded in Australia’s water markets, including forward contracts that are either linked or decoupled from allocation announcements, and lease contracts (term transfer of water entitlements). This article focuses on the allocation market, which is also known as the temporary water market. In the allocation market physical water is traded, based on allocation announcements by the regulation agencies. The article also makes mention of the water access entitlement market, which is also known as the permanent water market.

On the allocation market water users trade water that is physically held in a water storage and is available for consumptive or environmental use. Allocation markets are defined by a streamlined trading process (Figure 4). This streamlined process is possible because the permanent water asset (water access entitlement) is not changing hands.

water markets & trading

33

Feature Article

Figure 2. Southern Murray-Darling trading zones. (Source: National Water Commission)

Figure 3. Northern Murray-Darling trading zones. (Source: National Water Commission)

AUGUST 2015 water

34

Feature article

Table 1. Tradeable water rights.

Rights

Definition

Water access rights

The right to hold and take water from a water resource.

Water access entitlements

A perpetual or ongoing entitlement to exclusive access to a share of water from a specified consumptive pool as defined in the relevant water plan.

Water allocations

The specific volume of water allocated to water access entitlements in a given season, defined according to rules established in the relevant water plan.

Riparian rights

Water right held by rural landowners for domestic, on-farm purposes. Riparian rights allow landowners whose property adjoins a body of water to make reasonable use of it, for purposes such as drinking water, domestic use and fishing.

Stock and domestic rights

Water right held by rural landowners for domestic, on-farm purposes. Stock and domestic means uses such as household purposes, watering of animals kept as pets, watering of cattle or other stock, and irrigation of a kitchen garden.

Water delivery rights

The right to have water delivered by an irrigation infrastructure operator.

Irrigation rights

The right to receive water from an irrigation infrastructure operator, which are not water access rights or water delivery rights Allocation trades typically happen quickly because a significant proportion of market demand results from short-term needs, such as: • Elevated crop water demand due to unanticipated high seasonal temperatures or lack of seasonal rainfall events; • To manage carryover arrangements; and • Rebalancing of water accounts to avoid paying over-use penalties.

Figure 4 summarises the key steps in an allocation trade.

AUSTRALIA’S WATER MARKETS: hISTORICAL TRADING ACTIVITy By value, the water access entitlement market (permanent market) is the largest water market, whereas the allocation market is the largest measured by trade volume and number of transactions. In 2012–2013 the National Water Commission estimated that annual turnover in Australia’s water markets was $1.4 billion, down from $1.6 billion in 2011–2012. Of this, around $250–300 million involved allocation trades.

Marsden Jacob maintains a database of allocation water trades across the MDB that are used for price and trade forecasting. Figures 5 and 6 show price correlations in the southern and northern MDB. Figure 7 details the volume weighted average price (VWAP) and volume across the southern MDB over 2009–2015. These figures highlight that: • Southern MDB allocation prices converge, whereas in the northern MDB prices are trading zone-specific. Price convergence in the southern MDB reflects the ability to trade water across the inter-connected southern trade region. Northern markets are not interconnected, so these markets operate independently of each other.

• Prices in the southern and northern allocation markets are volatile and heavily driven by seasonal water availability. During the millennium drought the VWAP in the southern MDB peaked at $300 per ML. When the drought broke, prices tumbled to around $20–$30 per ML as supply exceeded demand, but more recently prices have increased and allocation water is currently trading for around $200 per ML across the southern MDB.

Figure 4. Allocation trade steps.

water AUGUST 2015

• Prices over the last three years have witnessed sustained growth, as has the volume of water being traded. Discussions with our network of market intermediaries suggest that the allocation market will remain strong and prices will increase in the 2015–2016 water year.

water markets & trading

35

Feature Article seasonality is a key driver of market activity.

Prices and volumes tend to peak during January to March and consecutive seasons in which many irrigators have not benefited from significant summer and spring rains, which means they are more dependent on regulated water supplies.

Increased demand for allocation water from irrigators Many irrigators want to continue to plant large crop areas, but they need more allocation water (than previously) to do this, because they have sold considerable volumes of water to environmental water holders.

Figure 5. Price correlations in the southern MDB, July 2013–April 2015.

(Source: MJA analysis, 2015)

Commodities The margin return that irrigators can make – typically measured as dollars per megalitre (ML) –influences how much irrigators are willing to pay for water. New commodities have emerged in the southern MDB, particularly cotton and nut plantations. It appears that these new commodities can afford to pay more for allocation and entitlement water than other producers.

THE FUTURE In this section we briefly discuss key allocation market drivers.

Water availability outlook

Figure 6. Price correlations and volume traded in the northern MDB, June 2013–April 2015. (Source: MJA analysis, 2015)

The amount of water on the market is determined by water availability. Across the MDB, there are poor water availability outlooks. The allocation outlook for 2015–2016 is weak across Victoria, New South Wales and Queensland. Only South Australia has announced full allocations for the 2015–2016 water year. The reason for the poor outlook in many areas is two-fold: 1. Dam storage levels are low and falling (see Figure 8); and 2. BOM has recently announced an El Niño in the Pacific, which means that there is an increased chance of a drier three months over southern parts of southeast Australia.

Irrigated commodity outlook

Figure 7. Three-month moving average VWAP and volumes by month southern MDB, 2009–2015. (Source: MJA analysis, 2015)

WHAT’S DRIVING CHANGES IN THE ALLOCATION MARKET? There are a number of key drivers behind allocation market activity and prices. These drivers are changing over time, with market reforms and as irrigators learn how to use the water market to their best advantage for their farming system.

Allocation (available water) The availability of water, both current and outlook, are key determinants of allocation market activity and prices.

Seasonality Across all markets, and particularly in the northern MDB,

Australia’s commodity outlook is also mixed.

In 2015–2016 ABARES reports that the total volume of farm production is forecast to increase by 5.3 per cent, which follows a forecast increase of 2.9 per cent in 2013–2014. However, production of many irrigated commodities is forecast to decline. For instance: • Total summer crop production is estimated to have declined by 4 per cent in 2014–2015 to 3.8 million tonnes, driven by falls in production of cotton and rice. The area planted to summer crops declined by 9 per cent to around 1 million hectares.

• Cotton: In 2015–2016 the return to Australian cotton growers is forecast to fall to $449 a bale (down from $490 a bale in 2014–

AUGUST 2015 water

36

Feature Article

4/06/2015 4/06/2015 10/06/2015 Public Storage Capacity !( 10/06/2015 Storage Air Space | <

Murray - Darling Basin Government Irrigation Storages - 10 June 2015 78.6

Beardmore (81.7 GL) Chinchilla (9.8 GL)

Current Public Storage Level Current Storage Volume

Cooby (21.166 GL) Coolmunda (69 GL)

Rivers

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Jack Taylor (10.1 GL)

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Lachlan Southern Basin

192 !

Burrendong Dam (1188 GL)

The copyright in this publication is licensed under a Creative Commons Attribution 3.0 Australia (CC BY) licence.

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Glenlyon Dam (254 GL) !

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Menindee Lakes (1731 GL)

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Dartmouth (3856 GL) Theassessment assessmentof ofwater waterstorage in storage does include water The does notnot include water in in privatestorage. storage.Private Pleasewater note, storage if the current storages private information is volume is higher than theformat total storage capacity,every this is3due to surcharge available inPDF and is updated months. levels. Figures in bracket refer to storage capacity in gigalitres.

Please note that some Current Storages Levels are higher than the total Storage Capacity, this is due to surcharge levels

Figure 8. Irrigation storage levels.

(Source: www.mdba.gov.au/sites/default/files/waterstorages/weeklybasinreports/MDB_Storage_2015JUNE10.pdf) 2015), reflecting a forecast decline in world cotton prices only partially being offset by a depreciated Australian dollar.

• Dairy: World dairy product prices are forecast to increase in 2015– 2016 in response to a moderate recovery in Chinese demand and increased demand from Asia, the Middle East and North

• In the northern MDB, allocation prices are expected to remain high, but market activity (particularly in northern NSW) is expected to be depressed because there is very little water available for trading.

Declining water availability and mixed commodity price outlooks

Africa. The Australian farm gate price for milk is forecast to average

mean that water use must be more carefully planned than ever. An

46 cents a litre in 2015–2016, a 5% increase over the 2014–2015

understanding of water markets and their outlook will assist irrigation

farm gate price. The price rise reflects an assumed depreciation of

and environmental water users to balance their water needs in light of

the dollar and forecast higher world dairy product prices.

rising prices and provide a stronger foundation for future budgets. WJ

• Almonds: Australia’s production of tree nuts has increased

Note: The information in this article has been prepared from a wide

significantly on the back of drought in California and increasing

variety of sources that Marsden Jacob Associates, to the best of its

global demand leading to elevated prices. ABARES reports that

knowledge and belief, considers accurate at time of going to print.

there has been a 90% increase in production over the past four years.

WHAT DOES THIS MEAN FOR WATER MARKETS? Our expectation is that the climatic outlook in particular has critical implications for allocation markets over the 2015–2016 water year: • Allocation trades will continue to be the dominant (by number) market segment. Many irrigators will turn to the allocation market to ensure that crops are either kept alive (in the case of drought), or returns are maximised (in the case of elevated water consumption); • In the southern MDB allocation prices are likely to remain high compared to the past few years, because of reduced water allocations, particularly in NSW; and

water AUGUST 2015

The Author Rod Carr (email: rcarr@marsdenjacob.com.au) is an Associate Director at Marsden Jacob Associates in Sydney. Rod has over two decades of experience in water markets, water infrastructure and government decision-making processes. Since joining Marsden Jacob in 2011, Rod has advised both private and public sector clients on rural and urban water market and infrastructure matters. Marsden Jacob Associates (www.marsdenjacob.com.au) is a leading natural resource economics consultancy specialising in solving practical and real world problems relating to water, energy, environment, natural resources, public policy and transport.

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Feature article

39

Feature Article

AUSTRALIA NEEDS A PLAN TO PROTECT THE OUTBACK’S PRECIOUS WATER Water provides a vital refuge in dry landscapes, supporting species that are not found anywhere else on earth, writes Jenny Davis in The Conversation. So why don’t we have a plan in place to protect our outback water resources?

T

he Australian outback is an iconic place. It is the nation’s great outdoors and represents a concept of wilderness that many Australians hold dear, and the Red Centre is at the top of many international tourists’ must-see lists.

While it covers more than 70 per cent of the continent, this vast area is home to less than five per cent of the population, and the Pew Trust describes it as one of the last extensive natural regions left on Earth. It is a landscape of great contrasts: it can be green, lush and bountiful, but also dry, dusty, harsh and inhospitable.

Above all, the Outback is defined by water scarcity across all but its most northern areas. As with most rare commodities, outback water, especially groundwater, is extremely valuable. It is critical to the persistence of natural ecosystems and sustains human settlements.

It seems bizarre, then, that there is no unified national plan to manage the water resources of the outback, and that such a project does not feature in the National Environmental Research Program unveiled earlier this year. If we want to safeguard outback water from the threat of overuse posed by fracking and other pressures, a proper outback water security plan is urgently needed.

What would the plan look like?

Similar to the Murray-Darling Basin Plan, an outback water plan must be based on a comprehensive understanding of the size, condition and variability of water resources – both surface water and groundwater – and of how they are connected together. It should

An unpredictable landscape Rainfall is low and unpredictable across inland Australia, but the rain events that do occur are often very large. They create the floods that flow through normally dry river networks to fill large inland lakes and wetlands, such as Kati Thanda (Lake Eyre) in South Australia and the Fortescue Marshes in Western Australia.

When the floods come, the newly filled waterbodies become sites of immense but temporary productivity. These large episodic rainfall events, followed by long dry periods, drive the boom-and-bust environments to which many outback species are well adapted.

But it is not just rainstorms and floods that sustain inland ecosystems. Groundwater is the hidden resource that has ensured the persistence of some species over millennia and supported most outback human endeavours. This underground water, being out of sight and potentially out of mind, is extremely vulnerable to overextraction and pollution.

The recent announcement that the Queensland Government will support unconventional gas exploration in the Cooper Basin suggests that we still have a very poor understanding of the importance of water, particularly groundwater, across the region.

Fracking (the extraction of unconventional gas) involves removing large volumes of groundwater and the disposal of water with high concentrations of various impurities. Fracking can result in pollution and depletion of groundwater resources far beyond recharge rates.

be a single plan covering Australian rangelands and deserts, and should take account of all the environmental, social, cultural and economic uses that these scarce water resources support.

More specifically, the plan should involve: • Determining the location and extent of aquifers and catchments that support key biodiversity and cultural sites, particularly in areas near proposed mines and other developments; • Working to understand how biodiversity hotspots and wildlife refugia depend on specific water resources; • Providing knowledge, training and logistics for indigenous and Photo: Jenny Davis

local communities to manage and restore important water sites in arid and semi-arid zones; • Ensuring that Environmental Impact Statements contain the information needed to assess the impacts of proposed developments on important water sites.

Go with the flow: scarce water has allowed Outback species to persist for millennia, where otherwise they might have died out.

AUGUST 2015 water

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Feature article

Meanwhile, the progress that has been made in mapping and understanding the extent of groundwater resources across the continent has been greatly reduced by the closure of the National Water Commission and reduction in support for the National Centre for Groundwater Research and Training.

saFe reFuGes For Millennia As my previous research has shown, water resources are vital refuges in dry landscapes. Some subterranean aquifers and mound springs supported by the underground waters of the Great Artesian Basin are “evolutionary refugia”, supporting species that have persisted for up to a million years and which live nowhere else on earth.

Springs in the Central Ranges support relict populations of aquatic insect species, such as mayflies, caddis flies and waterpennies, that were once more widespread but became isolated as the continent became increasingly dry.

Groundwater-fed springs across the outback are likely to be important refuges in the future because they are mostly decoupled from regional rainfall. However, if springs are polluted or allowed to dry completely, extinctions will occur because the specialised species they support cannot easily disperse to live somewhere else.

Much of Australia’s unique wildlife diversity is made up of outback plants and animals that have taken refuge at these groundwater sites during dry periods, thus allowing them to survive the boom and bust of the continent’s history. Although Australia is globally recognised as a “megadiverse” country, we cannot take this status for granted.

We know that multiple and interacting threats are altering the processes that support outback species. Introduced invasive

water AUGUST 2015

species and altered fire regimes are already of major concern.

If we add activities that change water quality and quantity, such as fracking, to the pressures that already exist, we could be at a tipping point in the decline of biodiversity across inland Australia.

The efforts to halt biodiversity decline – including the appointment of a Threatened Species Commissioner and a federally funded threatened species program – will amount to little if we ignore the fundamental issue of maintaining good-quality water resources. Water is a critical resource in the outback, and we need to know where it is, how much there is, how old it is and what depends on it, before it is allocated or polluted by new developments.

The need to provide greater surety of water for extractive industries and intensive food production must be balanced against the environmental and cultural values long associated with perennial springs and rockholes, desert river networks and episodic lakes.

Coal seam gas and mining have the ability to change and potentially destroy natural systems, on timescales far beyond our generation.

We need a water security plan for the outback that recognises the fundamental importance of water to everything we value – environmental, social and cultural, as well as economic. WJ

The auThor Jenny Davis is a Research Professor in Wetland Ecology at the University of Canberra.

Republished courtesy of The Conversation (theconversation. com/australia-needs-a-plan-to-protect-the-outbacks-preciouswater-43631).

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Feature Article

WATER RE-USE IN SOUTH AFRICA A shortage of water in South Africa is leading to increased interest in reclamation and re-use of wastewater to sustain development and economic growth, writes Jo Burgess. But gaining community support for potable re-use is still a significant challenge.

W

ater is a limited resource in South Africa, especially in western and northern areas where runoff exceeds rainfall. The pressure exerted on surface and groundwater resources should be reduced, or at best maintained rather than increased, as human population and industrial development grow. Vast volumes of surface or groundwater can be saved by replacing traditional sources with water re-use and recycling, which in an industrial setting lowers production costs, reduces pollution, improves carbon footprint, and enhances continuity of supply. In the catchment setting, re-use eases current pressures on surface water.

This shortage of water is creating large-scale interest in, and application of, reclamation and re-use of wastewater to sustain development and economic growth. Water re-use has been practised here since the 1960s, with the first direct water reclamation (DPR) plant being Goreangab in Windhoek, Namibia, after extensive demonstration and test work in Pretoria, South Africa. Ongoing research and development has led to this plant being internationally recognised as an established, effective multi-barrier treatment system.

South Africa regulates water quality according to its intended use, instead of according to its source, hence all potable water supplies are required to meet the national standard (SANS241-1:2011)1 regardless of whether the raw water was groundwater, surface water, treated wastewater or seawater. Using health risk-based standards and approaches similar to those set out in the World Health Organizationâ&#x20AC;&#x2122;s Guidelines for Drinking-Water Quality2, the national monitoring and evaluation requirements demand that a set list of determinants be measured in water entering the bulk supply system at set intervals, depending on the size of population or population equivalents being served by the supply. Direct and indirect potable re-use (DPR and IPR) schemes are subjected to a full environmental and social impact assessment (ESIA), including broad consultation with the affected communities and stakeholders. This process, supported by a rigorous regulatory approval, licensing and review of the technology used, ensures that public health and safety are guaranteed3.

Table 1. Potable water reuse schemes in South Africa.

Product end use

Main process

Implementation status

10

IPR

Ultrafiltration

Implemented

Beaufort West 2.3

DPR

Multi-barrier

Implemented

Location

ML/d

George Bellville, Cape Town

20

Potential IPR

Membrane bioreactor

Under construction

Port Elizabeth

45

Industrial reuse, potential IPR

Membrane bioreactor

Feasibility and Tender

Hermanus

5

DPR

Multi-barrier

Feasibility and Tender

Emalahleni

50

IPR

UF, RO, chlorine Implemented

Emalahleni

15

IPR

UF, RO, chlorine Implemented

Emalahleni

Water re-use schemes Table 1 lists a selection of recently implemented and currently planned re-use projects at the locations shown in Figure 1. Further description of some of the projects is provided in the following sections.

George: 10 ML/day IPR Plant (2009/10) As a popular tourism destination, George faced seasonal water shortages and decided on an IPR strategy where final effluent from its Outeniqua wastewater treatment works (WWTW) is treated to a high quality through UF 1

2 3

Figure 1. Map of South African potable water reuse schemes.

SANS 241-1:2011 Drinking Water Part 1: Microbiological, Physical, Aesthetic and Chemical Determinants, South African Bureau of Standards, Pretoria, South Africa, 2011.

World Health Organization (2011) Guidelines for Drinking-Water Quality, Fourth Edition.

AM van Niekerk and B Schneider (2014): Implementation Plan for Direct and Indirect Water Reuse for Domestic Purposes â&#x20AC;&#x201C; Sector Discussion Document, Research Report No. KV 320/13, Water Research Commission, Pretoria, South Africa. Available online at www.wrc.org.za/Pages/DisplayItem.aspx?ItemID=10623 &FromURL=%2fPages%2fKH_AdvancedSearch.aspx%3fdt%3d1%26ms%3d%26d%3dImplementation+plan+for+direct+and+indirect+water+re-use+for+dome stic+purposes+%e2%80%93+sector+discussion+document%26start%3d1.

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Feature Article and disinfection prior to being returned to the main storage facility, the Garden Route Dam, where it is combined with current raw water supplies. This initiative augments the existing supply by 10 ML/ day, approximately one-third of the drinking water demand. Final effluent from the WWTW is treated by drum screen, ultrafiltration and chlorination. Provision has been made for powdered activated carbon addition at George WTW, if required as an additional operational barrier. The product water delivered is of equivalent quality to Garden Route Dam water.

Beaufort West: 2.3 ML/day DPR Plant (2010) The town of Beaufort West shows a significant population growth due to increasing economic activities. The local municipality initialised a project to supply additional SANS241-1:2011 standard water as a result of a shortage of drinking water. The proposed solution for this problem was to build a plant for the reclamation of WWTW product water to deliver potable water. The reclamation plant is maintained and operated by Water and Wastewater Engineering in a 20-year agreement. The process implemented follows the multi-barrier concept: final effluent from WWTW, sand filtration, UF, two-stage RO, with permeate disinfected by ultraviolet light. The product water quality exceeds the national standard for potable water.

Port Elizabeth (Nelson Mandela Bay Municipality): 45 ML/day Membrane Bio Reactor (MBR) Industrial Re-use Port Elizabeth is a major development centre. The growth of industries and subsequent population growth creates an increased demand for water. The area is also currently affected by severe drought conditions, which place tremendous stress on existing surface water resources. The municipality and Royal HaskoningDHV are upgrading the existing Fishwater Flats WWTW to 170 ML/d. Planning and design are underway to provide advanced treatment in the form of MBRs and RO to supplement the existing water resources and provide industrial and potable water through indirect re-use. The first phase of the water re-use scheme will produce 45 ML/day, which will be suitable for industrial and/or IPR, with a second phase of similar capacity to follow.

Hermanus: 5 ML/day DPR Plant Drought conditions have resulted in a shortage of drinking water in the town of Hermanus.

Reclamation of effluent for DPR was selected to augment the existing surface water supply. The first phase of the project entails the construction of works to re-use 2.5 ML/day of effluent with civil works for a future increase in capacity to 5 ML/day. The process train uses UF pre-treatment and RO desalination, as well as advanced oxidation and carbon filtration, and the water quality exceeds SAN241. The product from the re-use plant will be fed directly into the drinking water reticulation system.

Emalahleni: 50 ML/d plus 15 ML/d, IPR The town of Emalahleni is served by two full-scale, operational mine water-to-potable supply plants: Optimum Water Reclamation Plant (OWRP) and eMalahleni Water Reclamation Plant (EWRP). The plants are operated by Anglo American Thermal Coal, 32South (formerly BHP Billiton), and Glencore (formerly Optimum Coal). The water is blended for IPR supplies to the local municipality. The town of 510,000 people is the energy hub of the country, providing 70 per cent of South Africa’s electricity generation, and is dominated by mining, steel, power and agriculture. Its main water source is Witbank Dam (capacity ~104 billion litres). The EWRP was first commissioned in October 2007 with establishment capital of R1.4 billion (US$175m) and a plant capacity of 30 ML/day treated water; expansion to 50 ML/day took place in 2011. The 15 ML/day OWRP assists the mine to operate successfully and to mitigate its impact on the downstream environment. Construction commenced in October 2008 and the facility was commissioned in September 2011. The total capital spend was R545m. The process trains in both WRPs include neutralisation followed by UF, RO and chlorination.

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Optimum Water Reclamation Plant (OWRP).

eMalahleni Water Reclamation Plant (EWRP).

Recent research The majority of research over the past decade has investigated greater efficiency in the engineering or scientific aspects of product water quality.

Decision-support model for the selection and costing of direct potable re-use systems from municipal wastewater Water supply authorities face challenges when diversifying the mix of raw water resources they use to provide potable supplies. Numerous options are available when planners want to improve water surety (and sustainability) or make provision for drought periods. Sufficient information is often not readily available for the planners or local authorities to make informed selection of the best options for a specific situation, especially regarding technical, costing, energy and environmental data. Even if the information is obtained, comparison of the best possible options is often not feasible, because of the differences in priorities assigned to the multitude of factors making up the main components of the selection criteria.

Swartz et al. (2014)4 created a decision-support system to be used to identify, evaluate, compare and select appropriate options that can be used to produce sufficient quantities of safe drinking water from available water sources. The guide also included the development of a re-use costing model, REUSECOST, and REUSEDSM, a spreadsheetbased decision support system was developed to provide a simplistic method to compare different re-use options using multi-criteria analysis. This model focused on DPR as a water-supply option to augment conventional water source in water scarce areas.

Wastewater reclamation for potable re-use The main objective of this research5,6 by Umgeni Water (a water board in the east of the country) was to evaluate the performance of different MBRs as a pretreatment step to produce potable water. Three MBR pilot plants were set up at a WWTW in Durban. Settled sewage was supplied to each pilot plant via a common balancing tank. The three plants utilised different

D Swartz, CJ Coomans, HP Muller, JA du Plessis and W Kamish: Decision-Support Model for the Selection and Costing of Direct Potable Reuse Systems from C Municipal Wastewater, Research Report No. 2119/1/14 Water Research Commission, Pretoria, South Africa, 2014. Available online at www.wrc.org.za/Pages/ DisplayItem.aspx?ItemID=10780&FromURL=%2fPages%2fKH_AdvancedSearch.aspx%3fdt%3d1%26ms%3d%26d%3dDecision-support+model+for+the+selecti on+and+costing+of+direct+potable+reuse+systems+from+municipal+wastewater%26start%3d1.

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Feature Article membranes: Toray (flat sheet), Norit (tubular) and Pall Corporation (hollow fibre). The Pall pilot plant was never successfully commissioned, so only the Toray and Norit pilot plants produced results.

The MBRs were evaluated daily for 12 months in terms of: permeate quality; fouling potential of the permeate; fouling rate (cleaning frequency); stable fluxes; and peak fluxes. The most important criterion was the composition of permeate. The permeate quality was evaluated in terms of the permeate water quality being able to consistently meet set water quality objectives and standards, including the removal of Contaminants of Emerging Concern (CECs, such as endocrine disruptors, pharmaceuticals and personal care products), for the production of potable water.

Although there were minor differences in product water quality between the processes, most were compliant with the SANS2411:2011 drinking water standard7. A parallel bench scale comparison of five different process trains, utilising different combinations of membrane bioreactors (MBRs), reverse osmosis (RO), ultraviolet light (UV), ozone (O3), nanofiltration (NF), and granular activated carbon (GAC) yielded results demonstrating that streamlined process trains such as MBR-RO-UV (replicating the Singapore process) or MBRNF-UV are as effective as treatment trains with additional processes such as ozonation and GAC (MBRO3/GAC-NF-UV). Cost estimates suggested that the membrane-based process MBR-RO-UV would require less capital investment than process MBR-O3/GAC-NF-UV, the ozone/GAC-based treatment process.

Challenges and Future Research South Africa’s current research questions are about what to monitor (microbiological, chemical, organic micropollutants, endocrine disrupting compounds and CECs), and how to undertake the process of public engagement.

Monitoring, management and communication of water quality and public acceptance in the direct reclamation of municipal wastewater for drinking purposes Water reclamation plants are operating in Emalahleni (IPR), Beaufort West (DPR), George (IPR) and Mossel Bay (industrial), while DPR in Durban and Hermanus is at an advanced planning stage. The main concerns regarding DPR focus on potential health risks. The aim of this project is to develop a framework for IPR and DPR, consisting of health risk-based monitoring (for compliance and operational barriers, including engineered buffers), funding sources and regulatory approval. The main impacts of implementation of the framework will be improved sustainability of supplementary and alternative drinking water supply to alleviate water scarcity, to improve health and to stimulate economic development.

An investigation into the social, institutional and economic implications of re-using reclaimed wastewater for domestic application in South Africa Despite people’s acknowledgement of water scarcity, the general public often has little knowledge of water treatment and wastewater management. The research literature is almost silent on community awareness and engagement on the issue of DPR. The need to engage communities is a principle enshrined within the South African constitution and is reiterated in the water service regulation strategy, which emphasises the need for citizens’ voice. The underestimation of this need cannot be more vividly illustrated than by the recent service delivery protests

in South Africa, stemming from experiences and/or perceptions of unsatisfactory service delivery, with drinking water being no exception. This project will provide an understanding of the social, economic and institutional implications and consequences of DPR. Emerging contaminants in wastewater treated for direct potable re-use: the human health risk priorities in South Africa The possible presence of CECs in reclaimed municipal wastewater is of critical concern because of potential adverse health impacts.

Criteria in the evaluation of DPR include: (1) primary health concerns of wastewater re-use that are the long-term health outcomes of ingesting chemical contaminants found in recycled water; (2) health risks of using recycled water as a potable water supply compared against similar risk by conventional water supplies; and (3) the need for toxicity assessments. This project will identify CECs in South African reclaimed potable water, their sources, pathways and receptors, potential risk from exposure to these chemicals, performance of water reclamation treatment systems and risks for DPR. Assessment of DPR systems for the removal of contaminants that may have negative health impacts will provide a good basis for the development of South African guidelines for implementation of barriers, monitoring programs and assessment programs to eliminate or minimise risks, and can improve public acceptance of reclaimed water.

Conclusion The real value of water is apparent only when there is a risk of running out. This is illustrated by projects such as the re-use initiative of Durban Water Recycling8 and Queensland’s Western Corridor Project. The most compelling drivers for IPR and DPR have been shortages of water in the locations where demand for potable water exceeds supply; the uniqueness of water’s diseconomies of scale, in as much as the more volume of water is required, the further one has to go to get it; the corollary economic comparison of re-use of wastewater versus discharge to the receiving environment; and the increasing demand nationally as the human population both increases and becomes more urbanised. Communicating with and engaging the broader community in a discussion of the role of potable re-use in our water future is still, however, a significant challenge. WJ

Acknowledgements The Author gratefully acknowledges the technical and cost data, and other information provided by the WRC, WRRF and AWRCE and their project teams. Some of this information was used in a global perspectives review article entitled “Global Research Agency Perspectives on Potable Water Reuse”, published in Environmental Science: Water Research & Technology. The co-authors, Julie Minton, Melissa Meeker and Mark O’Donohue and publishers, The Royal Society of Chemistry, are gratefully acknowledged.

The Author Dr Jo Burgess (email: job@wrc.org.za) is Research Manager, KSA 3: Water Use and Wastewater Management at the Water Research Commission in Pretoria, South Africa.

Metcalf, L Pillay, LC Murutu, S Chiburi, N Gumede and P Gaydon (2014): Wastewater Reclamation for Potable Reuse Volume 1: Evaluation of Membrane G Bioreactor Technology for Pre-Treatment, Research Report no. 1894/1/14, Water Research Commission, Pretoria, South Africa. Available online at www.wrc.org. za/Pages/DisplayItem.aspx?ItemID=11079&FromURL=%2fPages%2fKH_AdvancedSearch.aspx%3fdt%3d1%26ms%3d%26d%3dWastewater+reclamation+for+p otable+reuse+Volume+1%3a+Evaluation+of+membrane+bioreactor+technology+for+pre-treatment%26start%3d1.

6 G Metcalf, L Pillay, LC Murutu, S Chiburi, N Gumede and P Gaydon (2014): Wastewater Reclamation for Potable Reuse Volume 2: Integration of MBR Technology With Advanced Treatment Processes, Research Report No. TT611/14 Water Research Commission, Pretoria, South Africa. Available online at www.wrc.org.za/ Pages/DisplayItem.aspx?ItemID=11147&FromURL=%2fPages%2fKH_AdvancedSearch.aspx%3fdt%3d%26ms%3d%26d%3dWastewater+reclamation+for+potabl e+reuse+volume+2%3a+Integration+of+MBR+technology+with+advanced+treatment+processes%26start%3d1.

7 SANS 241-1:2011 Drinking Water Part 1: Microbiological, Physical, Aesthetic and Chemical Determinants, South African Bureau of Standards, Pretoria, South Africa, 2011.

8 Water & Sanitation Africa, Nov/Dec 2011. South Africa’s Award-Winning Seawater Desalination Plant 29-33; Celebrating a Decade of Achievement 4-5.

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water AUGUST 2015

For your convenience, the 2015 Australian Water Directory is now available online...

The AusTrAliAn WATer DirecTory 2015 26th Edition An invaluable resource and reference tool for the Australian water industry

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To view the digital version now visit www.awa.asn.au/WaterDirectory

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Conference Report

FIRST ASIAN WATER REUSE SYMPOSIUM The First Asian Water Reuse Symposium was held at Tsinghua University, Beijing in April 2015. It addressed a range of water issues currently experienced in Asia and looked at ways to secure water resources into the future. John Radcliffe provided this report.

China has long recognised limitations to its water resources, especially in the north, and has made major investments in bringing water from the south. More recently, it has been taking strong action to reduce pollution risks that have arisen from the rapid expansion of its economy since the 1970s, including water pollution.

Korea has been developing a thrust towards resource protection and a “green economy”, including water recycling in new development zones such as Incheon, north of Seoul. Japan, although better endowed with water resources than many countries, has most of its population living in densely developed urban environments.

In Asian areas generally, due to rapid population growth and urbanisation and strongly developing economies, challenges to meet water requirements are becoming increasingly serious.

A joint initiative by Tsinghua University (China), the Korean Institute of Science and Technology (KIST) and Kyoto University (Japan) has resulted in the development of the Asian Symposium on Water Reuse to provide a unique platform for local communication, but also to broaden concepts, ideas and models for water reuse globally. It is intended that the Symposium will be held annually and will be organised and chaired among the three organisations in turn. The first Symposium was held at Tsinghua University, Beijing, on 23-25 April 2015.

The Symposium was attended by approximately 100 participants, 70 of which were research and industry representatives, with the remainder being postgraduate students and post-doctorates.

Speakers and topics Symposium Chair Professor Hong-Ying Hu from the School of Environment, Tsinghua University, opened the conference.

He stressed the increasing problem of water shortages, that 40 per cent of the world would be living in areas of water stress, and that the problem was becoming especially chronic in China, limiting economic and social development. Rapid urbanisation will result in strongly increased domestic demand.

now beginning to address the great variability in waste standards being presented from different industries (there are 15 different discharge standards for industrial sectors in China), the necessity for source separation, and the consequent impact on the design of Wastewater Treatment Plants (WWTPs) and their capacity to achieve discharge standards to receiving waters – issues addressed in Australia through the creation of the Environment Protection Authorities from the 1980s. Added to that were issues of scope for domestic source separation and the relationship with stormwater management, discharge and its so far little practised separation from wastewater.

Dr John Radcliffe then made a presentation on Australia’s learnings from 25 years of experience with recycled water, highlighting the drivers of environment protection, the National Water Initiative, the drought (with its desalination and Advanced Water Treatment Plants), the change in governance with the abolition of the Ministerial Standing Council for Environment and Water and the National Water Commission, and the risk of complacency that has become evident since the end of the drought.

Professor Jorg Drewes, from the Technical University, Munich (although until recently having spent much of his career in North America), described developments in the United States. He alluded to the developing crisis in California, the introduction of some small direct potable schemes, and highlighted the need to recognise that de facto indirect potable recycling was already widespread. Upgrading of WWTPs was likely to become more common – Switzerland was currently upgrading the 100 largest of its 700 WWTPs. Robustness and reliability were required of reuse plants, with dedicated infrastructure appropriate to the influent being received. There must be an integrated approach linking water, energy and resource recovery.

Professor Yu Liu from Nanyang Technological University, Singapore, discussed the post-active sludge introduction era, highlighting the need for improved efficiency, potential energy neutrality, driven by both improved energy recovery and improved energy efficiency, matched to the influent load being treated at any given time. Currently, many plants lose 50 per cent of their energy.

The scope for nitritation and the anammox approach was discussed.

Subsequently, Professor Hiroaki Tanaka from Kyoto University spoke about potential global climate change risk impacts, the introduction of new technologies able to remove more and smaller pollutants but generating increased energy demands to do so.

Safety and energy were seen as the keys to water reuse, illustrated by addressing the specific water constraints of Okinawa.

Professor Xiaochang Wang (University of Architecture and Technology, Xi’an, China) confirmed the rising Chinese investment in membrane bio-reactors (MBR) (18 per cent of $US0.25b world

Increasing resource reuse would be required, although Beijing was already reusing 21 per cent of its water consumption in 2012. He noted that sources of water are much more complicated, and challenges will have to be tackled to ensure water safety and reliability. Different end users require different water quality, resulting in complicated system optimisation. The risks and challenges were outlined. However, no mention was made of a move to potable recycling.

Professor Yi Qian from Tsinghua University then discussed the requirements for setting up recycling systems and the need for standards. It was evident from her presentation that China is only

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Symposium participants – First Asian Water Reuse Symposium, Beijing (Tsinghua University).

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MBR market in 2006, rising to 37 per cent of $US1.17b in 2010 and by 2015, representing 27 per cent of annual Chinese WWTP investment. MBR is favoured in smaller installations, and tertiary MF/ RO/Advanced Oxidation in larger plants. The development of lowresistance, durable high-strength membranes was seen as a priority.

Ultrafiltration, coagulation and powdered activated carbon was an alternative train. Control of industrial pollutants potentially entering the influent stream was seen as increasingly important, especially as China was now beginning to enforce discharge standards to receiving waters. Again, protecting human and environmental health and developing energy cost-savings were seen as principal drivers.

Professor Sadahiko Itoh, Kyoto University, Japan, discussed how to reduce the extent of wastewater treatment or over-treatment within a risk framework to achieve greater efficiency.

Soil column experiments and soil aquifer treatments were being explored in Kyoto City to target chemicals of human health concern to achieve less expensive water supplies that could then be transferred to water treatment plants. To ensure an annual probability The modules of membrane of infection risk level of at least biological reactors at Qing He are three metres high, two metres 10-4/person/year, additional wide, approximately 500kg each treatment of water from the and are “pulled” on a monthly basis.

SAT aquifer by UV or MF followed by chlorination is adopted, achieving a human adenovirus reduction of 8.2 log10 and for rotavirus, 8.7 log10.

Professor Yunho Lee from the Gwangju Institute of Science and Technology, Korea, directed particular attention to the use of oxidation processes for the treatment of contaminants, including the deactivation kinetics of antibiotic-resistant genes and the formation of NDMA. He pointed out that using an H2O2 / ultra-violet treatment used five to 27 per cent more energy than ozonation. He also highlighted the increasing attention being given to concentric bromide molecule pollutants.

Professor Shin-ichi Nakao, Kogakuin University, Japan, described the development of a wastewater treatment and water reclamation system described as the “Integrated Intelligent Satellite System”, using multiple decentralised systems fitted with MBR and controlled remotely, eliminating the cost of trunk infrastructure to a large WWTP. Such systems may have considerable sludge accumulation.

Low-fouling membranes (zwitterionic and nonionic polymers) and membrane-cleaning technologies are being developed for such plants. Larger satellite systems (0.5 to 1.5ML/day) may have added reverse osmosis/nanofiltration for higher quality reuse. Up to 100 satellites in a system were suggested. Reuse water can be produced on a local/regional scale with such developments.

Professor Dong-Bin Wei from the State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, discussed the development of ecotoxicology tests to assess the safety of reclaimed water, converting their data into equivalent concentrations of corresponding reference substances. An index score and rank were proposed and the method had proved to be effective when water was added to a man-made lake.

Dr Young-june Choi from the Waterworks Research Institute of the Seoul Government described how recycled water was being used to rehabilitate environmental flows in Seoul. Dr Kui-Xiao Li from the Beijing Drainage Company described practical experience of the use of ozonation, which generally demonstrated good removal of organic pollutants and antibiotics but could be negatively affected by nitrate produced by anaerobic-anoxic-oxic processes or denitrification biofilter processes. The Symposium program also included a series of posters by participants who could not be accommodated on the speaking program.

Professor Seockheon Lee, Korean Institute of Science and Technology, explored issues of resource recovery, but gave primary attention to the water itself (12 per cent recovery in Korea in 2012) and the scope for energy utilisation via biogas. It may be noted that comprehensive water saving plans have been mandated by Korean law since 2006, and the National Water Reuse Master Plan was established in 2010 to achieve an annual reuse target of 2.57 billion tons in 2020. The government has also been strongly pushing the consolidation of water and wastewater management units to improve the efficiency of service operations. Decentralising WWTPs, the prohibition of ocean dumping of food waste from 2013, separation of food wastewater streams from WWTPs while managing their integration in energy production to achieve positive energy balances were major policies outlined.

On the final day, delegates made a field visit to the Qing He Wastewater Treatment Plant, which has three treatment trains.

The first, dating from 2002, has a capacity 200 ML/day using an inverted anaerobic-anoxic-oxic (A2/O) process. The second, from 2004, also with a capacity of 200 ML/day, has an A2/O process, each followed by a denitrification biofilter and submerged ultrafiltration. The third stage, operated from 2012, adds a further capacity of 150ML/day by using MBR, the largest MBR plant thus far operating in China. The streams after disinfection are used to supplement water in the lakes and forests adjacent to the Beijing Olympic Park, effectively improving the quality of the Qinghai River, and are also used for agricultural irrigation.

Photo: John Radcliffe

The Author

Model of the Qing He WWTP. The more recently added MBR train is at the left end of the site.

Dr John Radcliffe (email: john.radcliffe@csiro.au) is an Honorary Fellow in the CSIRO. Previously he was Director General of Agriculture in South Australia and a Murray-Darling Basin Commissioner, and later became Deputy Chief Executive of the CSIRO, followed by appointment as a Commissioner of the National Water Commission. He currently chairs the Research Advisory Committee of the Australian Water Recycling Centre of Excellence.

He was invited to make a presentation at the First Asian Symposium on Water Reuse, held in Beijing in April 2015.

AUGUST 2015 water

Photo: John Radcliffe

Conference Report

technical papers

Odour Management Curing Sewer Odours: A Biological Solution For A Biological Problem

S Adkins et al.

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NJR Kraakman et al.

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I Evanson et al.

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M Hartley

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Case study of an odour abatement project in the Adelaide Hills

Containment Of Odours

Design and implementation of ventilation and cover systems while maintaining operability

When Odour Control Is Not About Odour At All

A case study of hydrogen sulfides risk and mitigation

Water Allocation, Trading & Markets Trading Irrigation Water For Hydroelectricity

Trade prohibitions and possibilities in the East Kimberley, Western Australia

Stormwater Management Quantifying Water Quality Characteristics Of Stormwater

Assessment of untreated stormwater for the Adelaide Airport and Barker Inlet stormwater-aquifer storage schemes

P Reeve et al. 73

Saline Waste This icon means the paper has been refereed

WAIV Technology: An Alternative Solution For Brine Management

Results of a full-scale demonstration trial conducted at a location near Roma in Queensland

B Murray et al.

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R Koech et al.

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Irrigation Methods Trends In The Use Of Surface Irrigation In Australian Irrigated Agriculture

An investigation into the role surface irrigation will play in future Australian agriculture

Disclaimer: The papers in this section have been peer reviewed for relevance, clarity and contributing constructively to the sharing of knowledge about water. It is not intended that any conclusions drawn by authors may be used as validation of the performance of a process or product; AWA expressly refutes any suggestion that publication herein implies endorsement. Although reviewers consider the credibility of data presented, it is not possible for them to vouch for the accuracy of such data.

NEXT ISSUE:

SEPTEMBER 2015 • MEMBRANE PROCESSES • WATER & INDUSTRY • PRICE REGULATION & TARIFFS • COMMUNITY ENGAGEMENT

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WAIV unit – demonstration trial location.

• MANAGED AQUIFER RECHARGE

CURING SEWER ODOURS: A BIOLOGICAL SOLUTION FOR A BIOLOGICAL PROBLEM Case study of an odour abatement project in the Adelaide Hills S Adkins, L Vuong, C Saint, J van Leeuwen

ABSTRACT The South Australian Water Corporation (SAWC) has taken a holistic approach to wastewater odour and corrosion management. Data analyses of odour complaints, sewer corrosion hot spots, field sampling and subsequent computer modelling of the wastewater networks are important in identifying the sources of hydrogen sulfide (H2S) gas production and understanding the reasons for existing odour/corrosion areas. A holistic network approach has been taken to allow the corporation to develop costeffective odour and corrosion mitigation strategies aimed at controlling the ‘root cause’ sources of H2S gas generation.

Numerous large gravity-fed concrete sewer mains, laid in the1880s–1980s, transport sewage to new wastewater treatment assets and upgraded treatment plants. Many sewers were constructed specifically to serve industrial customers outside of the Adelaide metropolitan area and were built to ensure flow capacity for future housing developments.

Several of these wastewater trunk mains had slight gradients and, therefore, low flow velocities. Design rules used during this period protected the sewer mains via continuous local ventilation to mitigate potential sulfide generation due to the slow flows.

At the time, these areas were typically rural; consequently any odours were dissipated with no issue or complaints.

New urban expansion has been encouraged by the state government, supporting development of vacant land for domestic housing, including new high-density housing adjacent to wastewater treatment infrastructure.

This encroachment, coupled with society’s reduced tolerance of odours, has exacerbated odour complaints. As a consequence, many sewer vents have been deliberately blocked to reduce

customer complaints. Unfortunately this action has caused high H2S gas levels within the infrastructure, creating significant odour hot spots or, in some cases, resulting in costly sewer collapses.

This paper discusses current sewer infrastructure corrosion, odour problems and a successful odour abatement project undertaken in the Adelaide Hills.

The project incorporates biofiltration as a low-cost, efficient and environmentally friendly means of removing H2S. Keywords: Sewer corrosion, odour complaints, hydrogen sulfide, design rules, urban expansion, biofiltration.

INTRODUCTION AND BACKGROUND SAWC’s wastewater assets have been significantly degraded by longterm sulfide exposure and many require rehabilitation. The discharge of sulfide and subsequent release of hydrogen sulfide (H2S) into wastewater

infrastructure causes wastewater utilities across the world considerable concern and expense from public odour complaints, acid formation and infrastructure corrosion (Mori et al., 1992). H2S leads to the destruction of concrete/reinforced concrete infrastructure and is also the primary cause of odour complaints. H2S is heavier than air, extremely toxic and highly flammable. There are also considerable human health concerns (US EPA, 2003) and consequent work health safety (WHS) implications (Policastro and Otten, 2007).

A further serious problem with exposure to H2S is that individuals may not, after initial exposure, detect the odour due to olfactory paralysis (ATSDR, 2012).

Consequently, the reduction of sulfide compounds in wastewater infrastructure is a primary public health safety requirement and needs attention by any wastewater utility to control health risks and serious asset damage (see Figure 1).

Figure 1. Typical sulfide-damaged manhole asset.

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ODOUR MANAGEMENT

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Technical Papers

ODOUR MANAGEMENT

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Technical Papers

Figure 2. Typical air inlet duct (induct) above-ground vent is connected to the sewer via an underground pipe.

Historically, during World War 2 (WWII) many industrial zones were hastily built across Australia to accommodate wartime production needs, therefore, vital infrastructure for all major utilities, including railways, electricity, gas, water and wastewater assets, was constructed and extensively expanded. Post-WWII, successive governments offered initiatives and encouragements for industry to expand in Australia. This not only created jobs, but also required supporting infrastructure for both industry and workersâ&#x20AC;&#x2122; housing.

In Adelaide many large gravity concrete sewer mains were laid earlier, in the 1880sâ&#x20AC;&#x201C;1920s, to remove wastes and wastewater out of the city and metropolitan areas. In the 1950s and 1960s many of these sewers and wastewater treatment plants were at capacity and, therefore, new treatment assets and plant upgrades were undertaken (Marsden et al., 2003). Many were designed specifically to serve new industrial customers outside the metro area and built for sewer capacity for current and future housing developments.

Several of these wastewater trunk mains had slight gradients and, therefore, low flow velocities. Design rules used at that time protected the mains and reduced odour via continuous local ventilation to mitigate potential sulfide generation due to the slow flows (SAWC, 1996). These assets were typically laid in rural areas or dedicated easements (Department of Planning, 2015) adjacent to vacant land. Urban expansion has been actively pursued by the state government and has encouraged developers to utilise areas of vacant land and build homes adjacent to easements.

WATER AUGUST 2015

Figure 3. Typical air exhaust duct (educt) attached to an underground WWPS asset. The air is removed from the sewer wet-well via the chimney (venturi effect).

The emergence of high-density housing, coupled with societyâ&#x20AC;&#x2122;s reduced tolerance of odours, has exacerbated odour complaints and, consequently, many vents have been blocked to reduce customer complaints. Unfortunately, this action has caused high H2S gas levels within the infrastructures and in some cases results in costly sewer collapses.

Additional use of pumped sewer mains has exacerbated the odour problems, as sewer pumping mains (or rising mains) are associated with long anaerobic retention times, which encourage the production of hydrogen sulfide-producing bacteria and bio-films (Kitagawa et al., 1998).

This situation is also asset/catchment dependent, as temperature, pipeline

length and waste sources (which may be domestic, industrial or a combination of both) have a significant bearing on H2S production (Nielsen et al., 1998). It is obvious that the review and refurbishment/reinstatement of necessary inlet or inducts and exhaust vents or educts would not solve these odour complaints and issues. Examples of air inlet ducts and exhaust vents (or chimneys) are shown in Figures 2 and 3.

Over several years, substantial research has been committed to finding permanent cost-effective solutions for H2S reduction or removal (Johnson et al., 2009). Furthermore, research for broad hydrogen sulfide compound abatement has been carried out for a variety of

Figure 4. Catastrophic H2S gas corrosion of induct asset. Note this structure is designed as an inlet sewer vent, but copious sulfide has been discharged.

(Source: Lynton Bishop)

dosing chemicals, including ferric chloride, calcium nitrate, magnesium hydroxide and direct oxygen injection.

These field trials were conducted to ascertain chemical costs and process efficiency and, in the wastewater research catchment, ferric chloride emerged as the best solution (Nguyen et al., 2009). Earlier research conducted

by Mohanakrishnan et al. (2008) highlighted the effects of nitrite on H2S reduction. Subsequent additional research on the use of nitrates to reduce bio-film growth directly in pumping mains was investigated by Jiang (2011), using a proprietory reagent, free nitrous acid (FNA). Further field trials by Jiang et al. (2013) showed that the reduction of biofilms post-dosing with FNA lasted several weeks from a single application.

Product release onto the market is currently being investigated by the University of Queensland’s commercial venture company Cloevis (Leemon et al., 2015). Cloevis and USP Technologies (formerly US Peroxide) are developing this product, but no further information is currently available.

Restricted sewer ventilation may result in high H2S gas availability within the wastewater infrastructure. The design of inducts and educts relies on convection and the venturi effect of the educt ‘chimneys’ to circulate the air.

However, the sewer headspace air may, in fact, travel both ways. This scenario may cause significant odour emissions and, in certain circumstances, severe corrosion of venting structures (see Figure 4).

SAWC has been monitoring sewer odours and addressing odour complaints over an extensive period and has subsequently embarked on an acrossstate holistic approach to odour control management. This process includes prudent, proactive and continuous monitoring of assets at risk, which may assist in early damage detection so that subsequent remedial action can be scheduled.

Recent projects have enhanced SAWC’s knowledge and this has produced cost-effective solutions for control and reduction of H2S and odour complaints (Cesca et al., 2015). In this paper we report a successful case study where proactive management of several odour complaints in the Adelaide Hills was achieved using a biological treatment process.

CASE STUDY: MILAN TERRACE, STIRLING SAWC has many small wastewater treatment plants (WWTPs) located in the Adelaide Hills. The case study reported here summarises the history of odour and corrosion issues in the Heathfield wastewater network (WWNW) and the success of the biofilter installed at Milan Terrace wastewater pump station (WWPS) 306.

The Heathfield WWNW comprises gravity sewers, 20 WWPSs and numerous sub-catchments of low-pressure sewer systems. The Heathfield scheme is unique in that it has muliplte relift WWPS to transport wastewater from the far reaches of the Mount Barker sewer catchment to the Heathfield WWTP. This particular sewer catchment had a history of odour problems, especially around the Aldgate area where Milan Terrace WWPS 306 is situated. Research deriving from an Australian Research Council (ARC) Linkage Project on Optimising of Odour and Corrosion Management (LP0882016), known as the Sewer Corrosion & Odour Research (SCORe) project, has demonstrated that wastewater rising mains are an issue. The pipe system presents an optimum environment for H2S formation, particularly when biofilms and standing wastewater become anaerobic in the main.

The Milan Terrace WWPS 306 accepts almost half of the sewage from the entire Heathfield catchment and relifts the effluent to the Heathfield Road WWPS 309. This effluent is then pumped to the Heathfield Wastewater Treatment Plant (WWTP). The treatment plant receives both gravity flow and pumped sewage from a number of stations. As a result, the H2S levels are very high at WWPS 306, due to the age and long detention times of the sewage by the time it arrives at this location. The community finds H2S offensive at levels of 3–10 ppm and the gas may be characterised by a rotten egg smell. Examples of H2S corrosion are shown in Figures 4 and 5, which picture corroded sections of the WWPS 306 sump lid.

During recent years, SAWC has received an increasing number of odour complaints for various reasons, including: • Higher social expectations; • Lower flows coming into the sewer networks due to greater public awareness of saving water, meaning less dilution is available in the network causing higher biological loading;

Figure 5. The Milan Terrace WWPS sump lid was replaced in September 2012 due to severe corrosion and steel patches have been welded to prevent WHS issues. (Source: Lam Vuong) • Sewer disposal of non-potable water recycling and increasing greywater use, causing higher salinity and biological loading; • More low-pressure sewer schemes being installed in this particular network; these act as mini rising mains and may be poorly maintained.

The level of H2S both in liquid and gas phase is dependent on the wastewater quality, detention time of sewage under anaerobic conditions, time of day, pH and seasonal variations. Another major factor is temperature, and H2S problems are likely to be more prominent during summer months. The long detention times in rising mains upstream of WWPS 306 have resulted in the production of high H2S levels. On some days, odour logging has detected readings of H2S up to 150 ppm at WWPS 306. SAWC has received numerous odour complaints from residents adjacent to the Milan Terrace WWPS and these were referred to the relevant state government minister due to their being perceptible all year round.

Since 2008, there have been various attempts to control the odour problem at Milan Terrace. Operational mitigation works have been implemented in an attempt to improve the situation, including: • A ‘whirly bird’ ventilator installed on the educt vent at Milan Terrace; • Installing two ‘push’ type fan units on the WWPS sump and another at the induct approximately 20 metres from the Churinga Road discharge manhole; • Targeted sewer cleaning; • Installation of carbon filters on educts; • Push type fans at Milan Terrace WWPS and at the Churinga Road rising main discharge from WWPS321.

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Figure 6. H2S logging at the control access manhole at Milan Terrace WWPS in 2011.

However, these actions did not have any significant long-term impact on the odour issue. Attempts by SAWC Outer Metropolitan operators in 2009 to reduce the odours by installing additional fans to push air into the network and Milan Terrace wet-well met with minimal success. The fan installation was designed to dilute/regularly change the air, but with the high levels of H2S, this was very difficult to achieve.

Subsequently, there were still odour complaints from local residents after the installation of the fans. Therefore, due to the increasing odour problems at WWPS 306, a bioflter was installed in 2011/12 to reduce the problem at Milan Terrace in conjunction with an odour investigation of the whole Heathfield WWNW, by external consultants.

The other associated problem at Milan Terrace is significant asset corrosion directly attributed to H2S. Consequently, in 2010 an access chamber and discharge manhole were rehabilitated using a calcium aluminate concrete (CAC) coating to prevent rapid corrosion.

The first stage of the project involved wastewater hydraulic modelling to investigate if diverting or removing current sewer flows away from Milan Terrace WWPS would be beneficial in eliminating the root cause of the complaints. Conversely, the additional installation of a new and potentially longer rising main would not reduce the H2S challenge.

Consultants were engaged to investigate the H2S problems across the

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Heathfield wastewater network in order to develop a holistic understanding and approach to odour control management that could be adopted. Sewage liquid and gas sampling were performed in the Heathfiled sewer catchment and a sulfide model was produced. This model demonstrated where the H2S production was most prominent and where SAWC could achieve best capital investment value to reduce odours. A report was completed in May 2012 and confirmed that the optimal position for the biofilter was the Milan Terrace WWPS. Odour logging performed at Milan Terrace WWPS confirmed that peak release of H2S emanated from this asset.

The topography of this area is quite low and, as H2S gas is heavier than air, the gas surrounds this WWPS and accentuates localised odour issues. From Figure 6, it can be seen that the sulfide logging performed in 2011 to develop an installation design for a biofilter revealed that H2S peaked at approximately 150 ppm (blue graph). This idea was based on positive results from the installation of two biofilters already operating at other SAWC locations â&#x20AC;&#x201C; one located at WWPS 1 Gordon Street and the other at WWPS17 located at Gertrude Street, Port Pirie in 2010. All biofilter systems currently in use by the SAWC are of Australian design and manufacture.

capacity for hot weather events. The vented air treatment capacity design is more complex, as the plant capacity has to accommodate additional network air from Churinga Road to Milan Terrace, a total of 580m3 per hour.

The criteria for selecting the biofilter were to provide a cost-effective proven technology that: treats H2S; requires minimal maintenance; demonstrates low operating costs; and reduces upstream asset network corrosion, in this case, towards the Churinga Road discharge manhole. This particular biofilter system consists of two containers, 2.4m in diameter each and approximately 2.2m high. Each unit has three layers of biomedia containing biomass, which accommodate H2S consuming bacteria.

These layers are approximately 500mm thick and separated by a layer of air, to prevent the compaction of the biomedia.

This allows an optimum surface for any sulfide gas to be exposed to the H2S consuming bacteria. The biomedia environment is controlled by water sprayed onto each layer four times a day.

BIOFILTER OPERATION

The system provides a two-stage process, with the first unit removing 90% of H2S and the second stage the residual 9%, without the reliance on carbon. While 99% seems excessive, it is quite critical at high H2S levels that any residual not be detectable at the outlet, otherwise odour complaints will continue.

The design criteria for the Milan Terrace biofilter are to accommodate a H2S peak concentration of 350 ppm and to provide contingency sulfide treatment buffer

The operation of the biofilter unit is as follows (see Figure 7): foul air is extracted by a fan unit from the wet-well; through the two tanks in series, containing a

Figure 7. Schematic diagram of the Milan Terrace WWPS biofilter and module airflows. (Source: Sarah Adkins)

Figure 8. Milan Terrace WWPS biofilter and module airflows.

(Source: Sarah Adkins)

proprietory biomass material; and the treated air is driven by the fan out through an exhaust vent. An activated charcoal filter is provided for use during preventive biomedia maintenance or as an emergency measure. The airflow is shown in Figure 8. Yellow arrows indicate foul air and sky blue arrows indicate treated air.

ADVANTAGES AND DISADVANTAGES OF THE BIOFILTER Advantages • Low running costs compared to other technologies; • The media (a proprietory mix) is replaced every three years at relatively low cost;

Figure 9. Logging at the inlet of the biofilter in July 2012.

• Reduces high levels of H2S that causes odour complaints and extends asset life by reducing humidity and hydrogen sulfide levels; • The environment can be controlled in a tank rather than being exposed to the weather, and this ensures optimum conditions for the bacteria to survive and thrive; • Compost biomedia can be easily disposed of when exhausted; • The fan ensures ventilation of the WWPS, keeping humidity low; • No requirement for an educt and, unlike other biological systems, the unit does not rely on a carbon filter to remove H2S. Disadvantages • Large footprint required for installation; • Additional maintenance cost;

Figure 10. H2S gas detection data at the biofilter outlet in July 2012. The magenta graph represents air temperature; the orange line is the sulfide detected by the sensor. This measurement is at or below the instrument’s detection limits downstream of the biofilter during the same period, demonstrating ~100% H2S removal (App-Tek, 2014).

• May have a negative visual impact, though the size and colour of the tanks can easily be designed to blend into the surrounding environment.

• Proprietory biomedia consist of sea shells, coconut husk, lime, sugar cane and other undisclosed materials, so is not ‘dirt cheap’.

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Technical Papers RESULTS AND CONCLUSION After the biofitler was installed, the SAWC assets group performed an onsite investigation of odour control and, hence, biofilter performance. H2S monitoring was performed with two Aptek oda-loggers to assess the biofilter performance at WWPS 306 Milan Terrace during July 2012, for two weeks. Figures 9 and 10 show graphs of H2S data detected at the inlet of the biofilter before treatment and at the outlet. The H2S concentrations are shown in Figure 9, where 90 ppm peaks are evident.

Figure 10 demonstrates that the biofilter had removed ~100% of the H2S during the logging period.

From the SCORe project, evidence suggests that humidity is one of the major contributing factors to corrosion, and therefore this design of biofilter should reduce both H2S and humidity. Basic operation of the biofilter is totally reliant on airflow through the biomass. The foul air is ducted from the wet-well into the base of the first treatment tank, which contains three independent levels of biomedia. Omri et al. (2013) suggest that the humidity within the biofilter structure is critical to the efficacy of the biomass, and therefore humidity was also measured onsite. The results are shown below: • Outside air humidity – 59%; • Access chamber humidity with the fan on – 77%; • Access chamber humidity with the fan off – 81%.

In this particular system, humidity in the tanks is maintained by automatic water injection sprays between the biomass layers four times a day.

To date, the Milan Terrace biofilter installation has performed effectively as designed. Local residents are very happy with the results and there have been no odour complaints since the biofilter was commissioned. However, odour monitoring will continue to determine if the biofilter continues to function as intended and prevents odour release and complaints from re-occurring. Investigating the catchment as a whole has worked well, as it ensured that the sulfide problem could be traced to the largest source of H2S. The successful biofiltration treatment of the H2S should result in corrosion reduction of existing concrete and steel assets at the Milan Terrace WWPS, extending the asset service life.

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As stated earlier, the reintroduction of inducts and educts on sewer assets is not a practical solution, but the use of biofilters and, where appropriate, additional chemical dosing, provides a cost-effective odour control solution for the corporation and its customers.

THE AUTHORS Steve Adkins (email: steve. adkins@sawater.com.au) is Networks and Monitoring Coordinator for SA Water Corporation. Steve has over 40 years’ experience with instrumentation, remote sensing, SCADA and statistical process control.

Lam Vuong (email: Lam. Vuong@sawater.com.au) is Senior Strategic Asset Engineer with SA Water.

He has 11 years’ experience in sewer network design and sewer management, specialising in optimal management of odour and corrosion in the sewer networks.

Professor Christopher Saint (email: Christopher.Saint@ unisa.edu.au) is Director of the Centre for Water Management & Reuse, University of South Australia.

Associate Professor John Van Leeuwen (email: John.

VanLeeuwen@unisa.edu.au) is a lecturer and researcher at the Centre for Water Management and Reuse, University of South Australia. John has approximately 25 years’ experience in the areas of water and wastewater quality, treatment and modelling.

REFERENCES App-Tek (2014): OdaLog® Type L2 Technical Specifications, App-Tek, Brisbane, viewed 3 May, www.odalog.com/odalog/odalog-l2.htm.

ATSDR (2012): Hydrogen Sulfide (H2 S), Atlanta, Georgia, USA. www.atsdr.cdc.gov/Mhmi/ mmg114.pdf.

Cesca J, Sharma K, Vuong L, Yuan Z, Hamer G & McDonald A (2015): South Australia Water Corporation’s Pro-Active Corrosion and Odour Management Strategy Development, Ozwater'15, AWA. www.ozwater.org/sites/all/ files/ozwater/052%20JCesca.pdf.

Department of Planning, TAL (2015): Easements, Department of Planning, Transport and Infrastructure, Adelaide, South Australia.

Jiang G, Gutierrez O & Yuan Z (2011): The Strong Biocidal Effect of Free Nitrous Acid on Anaerobic Sewer Biofilms. Water Research, 45, 12, pp 3735–3743.

Jiang G, Keating A, Corrie S, O'Halloran K, Nguyen L & Yuan Z (2013): Dosing Free Nitrous Acid for Sulfide Control in Sewers: Results of Field Trials in Australia. Water Research, 47, 13, pp 4331–4339.

Johnson I, O’Hallorah KSC & Neethling A (2009): Overcoming Difficulties in Providing Accurate Continuous Online Dissolved Sulfide Monitoring at Gold Coast. 34th Annual Queensland Water Industry Operations Workshop, Caloundra, Queensland, Australia.

Kitagawa M, Ochi T & Tanaka S (1998): Study on Hydrogen Sulfide Generation Rate in Pressure Mains. Water Science and Technology, 37, 1, pp 77–85.

Leemon H, Fillmore D, Keating A, Jiang G, Sarathy S & Yuan Z (2015): Development of an Effective Strategy for Sulfide Control in Sewers using Free Nitrous Acid, Ozwater'15, AWA. www.ozwater.org/sites/all/files/ ozwater/015%20HLeemon.pdf.

Marsden S, Cosgrove C & Taylor R (2003): Twentieth Century Heritage Survey, Government of South Australia, Adelaide, South Australia.

Mohanakrishnan J, Gutierrez O, Meyer R & Yuan Z (2008): Nitrite Effectively Inhibits Sulfide and Methane Production in a Laboratory Scale Sewer Reactor. Water Research, 42, 14, pp 3961–3971.

Mori T, Nonaka T, Tazaki K, Koga M, Hikosaka Y & Noda S (1992): Interactions of Nutrients, Moisture and pH on Microbial Corrosion of Concrete Sewer Pipes. Water Research, 26, 1, pp 29–37.

Nguyen T, Nobi N, Soliman A & Sharma K (2009): Case Study of Using Sulfide Model to Optimise Chemical Dosing for Odour and Corrosion Control. A collaborative research project by Sydney Water, Gold Coast Water and the University of Queensland, Australia.

Nielsen P, Raunkjær K & Hvitved-Jacobsen T (1998): Sulfide Production and Wastewater Quality in Pressure Mains, Water Science and Technology, 37, 1, pp 97–104.

Omri I, Aouidi F, Bouallagui H, Godon J-J & Hamdi M (2013): Performance Study of Biofilter Developed to Treat H2S from Wastewater Odour, Saudi Journal of Biological Sciences, 20, pp 169–173.

Policastro MM & Otten E (MDb 2007): Case Files of the University of Cincinnati Fellowship in Medical Toxicology: Two Patients with Acute Lethal Occupational Exposure to Hydrogen Sulfide, Journal of Medical Toxicology, 3, 3, pp 73–81.

SAWC (1996): Sewer Construction Manual, SA Water Corporation, Adelaide, South Australia.

US EPA (2003): Toxicological Review of Hydrogen Sulfide. United States Environmental Protection Agency, Washington DC, USA.

CONTAINMENT OF ODOURS Design and implementation of ventilation and cover systems while maintaining operability NJR Kraakman, J Cesca, G Hamer, R Aurisch

INTRODUCTION Due to the nature of their functions, wastewater treatment plants (WWTPs) and wastewater collection systems (sewers) generate varying concentrations of odorous gases. The complete containment of these odorous gases has never been easy, mainly because containment is difficult to quantify and subject to ever changing conditions like wind. Moreover, odour containment covers inevitably have openings for access requirements and instrumentation, but also because of wear and tear over time and, sometimes, poor installation due to the lack of quality control.

Odours emitted from WWTPs and sewers are a problem of increasing concern, because of several relatively recent changes. Firstly, heavy metals have been largely removed from sewage due to tighter controls of the waste and, consequently, the formation of odorous gases in the sewer has increased. Secondly, water restrictions and innovations in water saving devices have resulted in an increase in the concentration of pollutants in the sewer, leading to increased septicity when entering the WWTPs. Thirdly, there is a growing trend towards more centralised WWTPs in many large cities, especially with the amalgamation of wastewater authorities into larger utilities. Although this makes economic sense, it can result in longer retention times in sewerage as the wastewater from new outer suburbs has to travel further to reach an everlarger treatment facility.

Having a larger facility treating potentially more septic wastewater inevitably results in a bigger odour source. Furthermore, encroaching development and higher community expectations have often increased the risk of odour complaints and the need for more robust solutions, including improved containment.

This paper discusses the containment of odours by, firstly, illustrating the theoretical basis of design for ventilation systems to obtain near complete odour containment while minimising the risk of asset corrosion under covered process units at WWTPs. Secondly, a case study will be presented to demonstrate successful implementation of odour containment, where a proactive approach was chosen to address encroaching development and increasing community expectations.

PART 1: CONTAINMENT OF ODOURS The containment of odour is a function of the negative pressure under the cover.

Sufficient negative pressure must be created to negate the following forces to ensure no escape of odorous air from under the cover: • Wind The first force to be negated is the pressure difference created by air movement over the surface of a cover with an opening. The speed at which wind passes over odour containment covers, as well as along buildings that accommodate odorous sources, has a large influence on the magnitude of leakage. The wind condition over a site is a function of the local environment (topography, ground roughness, nearby obstacles), but is usually the most important force that needs to be overcome.

• Buoyancy The second force to be negated is the buoyancy caused by the density difference between the inside and outside of a tank or process unit. This is also known as the stack effect. For some applications this force can be neglected as it will be relatively small when the temperature difference is less than 10°C for ambient temperatures around 20°C. For conditions such as cold climates, relatively warm process temperatures, or for large distances between the liquid and the air vent heights, this force increases and will have to be taken into account (e.g. relatively

warm digested sludge in the sludge holding tank and buildings containing large thermal loads).

• Displacement The third force is caused by air or liquid forced into the covered process units (e.g. aeration in grit tanks or the pumping of liquid into a tank causing the liquid level to increase). The liquid level inside tanks changes when there are differences in the filling and emptying rates.

Air needs to be extracted from the covered sources to overcome the sum of the above three forces that will otherwise result in odorous air escaping from under covers. The total amount of extracted foul air that will have to be treated in an odour treatment facility can be minimised by using properly sealing covers. The effectiveness of covers to contain odours can be measured and is directly related to the size and number of the gaps in the covers. The smaller the sum of all opening of gaps in the cover, the more effective a ventilation system is in maintaining the required negative pressure. The relationship between the negative pressure under a cover and the total area of openings can be derived from Bernoulli’s equation: dP = Qg2 / (2 *Cd * A)2 * p

(1)

where: dP = the difference between the static pressures under and above a cover (Pa) Qg = the extraction rate from under the cover (m3/s) A = the total leakage area in the cover (m2) Cd = the discharge coefficient, typically 0.60 - 0.65 for sharp-edged inlets and turbulent flow (-) p = the air density (kg/m3) From equation (1) it can be determined that reducing the total leakage area (A) by a factor of two will result in an increase of the negative pressure under a cover by a factor of four. The same

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• Wind

at which air containment will be lost due to the pressure difference created by air movement above the cover, using the equation derived

by Cadee and Wallis (2007):

• Buoyancy

Vw = V0 / (Cd * Cwo1/2)

• Displacement

The global wind pressure coefficient (Cwo) is defined as the fraction of the dynamic pressure of the free wind acting on the outside of a structure (see also box ‘Negate the Effect of Wind on Covers’), calculated as:

In summary, the factors that influence fugitive air leaks from covered sources are:

• Net air extraction • Area of openings for the air to escape.

ODOUR CAPTURE PERFORMANCE In this paper, Odour Capture Performance has been taken to be the percentage of time (percentile) that a ventilation system provides sufficient extraction from a covered area to eliminate fugitive odour emissions.

Odour Capture Performance can be calculated and requires basically three input parameters: the negative pressure, the air extraction rate at the covered process unit, and regional wind speed data. The Odour Capture Performance of an individual covered process unit can be determined as follows: Step 1:

Step 2:

Measure the foul air extraction rate from the process unit (Qg) and measure the differential pressure over the cover of the process unit (dP) under no-wind or calm conditions.

Calculate the total area of opening (A) or the so-called total leakage area, using Bernoulli’s equation: A= Qg / ( Cd*(2*dP/p)1/2)

(2)

using a nominal value for the discharge coefficient (Cd) of 0.60–0.65.

Step 3:

Cwo = Cp * (K * za)2

(4)

(5)

The external pressure coefficient (Cp) is typically 0.9 (AS/NZ 1170.2, 2002). The height of covers above ground level is z.

The coefficients to include the effect of height and topography on the wind velocity acting on the covers (K and a) are selected from Table 1 (see box ‘Negate the Effect of Wind on Covers’).

Step 5:

Derive the per cent of the time that the velocity across the opening (due to foul air extraction) negates the effect of wind (Vw). The regional wind data consisting of the statistic percentile of the wind speed can be plotted as shown in Figure 1. The resulting value is what can be defined as the Odour Capture Performance for that covered process unit under the local wind conditions.

For example, when the pressure under a cover is negative 15 Pascals (measured during low or no wind conditions) and the extraction rate is 0.5 m3/s, it can be calculated that the total leakage area will

be about 0.2 m2. The influence of wind on the containment can be determined when the cover height is defined (e.g. 2m) and the topographical location is defined (e.g. Open Country – many windbreaks).

In this case, the wind speed (Vw) at which air containment will be lost due to the pressure difference created by air movement over the cover will be about 8.8 m/s. That cover at a location with regional wind characteristics as shown in Figure 1 would result in an Odour Capture Performance of about 95% (95% of the time foul air will be contained under the cover). When that pressure over the cover is only negative 5 Pascals, the Odour Capture Performance will be only about 60%, meaning only 60% of the time foul air will be contained under the cover (see also Figure 1).

The impact of wind speed (Vw) on a cover is influenced by the topographical conditions. Open spaces with minimal obstructions will have a larger impact than when the wind is slowed down by surrounding obstacles like buildings and trees. The required negative pressure under a cover for typical topographical conditions around WWTPs for wind conditions like Sydney along the coast is illustrated in Figure 2.

The figure shows the negative pressure required for three topographical conditions when only the effect of wind has to be negated. It can be seen that at negative 15 Pascals Odour Capture Performance is about 99% for the topographical conditions defined as Rough Country (typical for inland WWTPs near a small town).

This Odour Capture Performance is only about 85% for the topographical conditions defined as Open Country – few wind breaks (typical for WWTPs

Calculate the average velocity across the openings (V) by using equation (3): V= Qg / A

(3)

Note: This is the average air velocity through the opening, caused by all forces except wind. The main force will be the extraction by the fan, but could be buoyancy or displacement in some cases.

Step 4:

Calculate the wind speed (Vw) up to where the air velocity across the opening negates the effect of wind above the cover (Vo). This is the wind speed

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Figure 1. Example of wind speed for Sydney along the coastline as percentage of the time measured over the period 2001–2014.

NEGATE THE EFFECT OF WIND ON COVERS Odour containment is achieved by maintaining a negative pressure over the cover of a process unit. dP = Pinside - Poutside

(7)

Poutside = Patmosphere - Cp * p * [Kw * Vw]2 / 2

(8)

with Cp the external pressure coefficient (-), Vw the free wind speed measured at the standard height of 10 meter (m/s) and Kw the velocity coefficient related to the topography and height of a structure (-) Thus when combining equation (7) and (8) dPwind = Pinside - Patmosphere - Cp * p * [Kw * Vw]2 / 2

(9)

dPwind = dPmeasured over cover - Cp * p * [Kw * Vw] / 2

(10)

2

The velocity across an opening (V) may be derived from Bernoulli’s equation: (11)

(12)

or

The pressure on the outside surface of the cover (Poutside) may be calculated as:

V= Cd*(2*dP/p)1/2

V0= Cd* Cp1/2 * Kw * Vw

(6)

An important force to overcome (for maintaining odour containment) is the pressure difference created by air movement over the surface of the cover. dPwind = Pinside - Poutside

The velocity (V0) across an opening that negates the effect of wind on the cover (dPwind = 0) is given by combining the last two equations above:

Vo= Cd * Cwo

1/2

* Vw (13)

with the global wind pressure coefficient (Cwo), defined as the fraction of the dynamic pressure of the free wind acting on the outside of a structure. While Cwo = Cp * (K * za) 2 and

Kw = K * za (14)

with the external pressure coefficient (Cp) being typically 0.9 (AS/NZ 1170.2,2002), and the height of covers above ground level (z), and coefficients to include the effect of height and topography on the wind velocity acting on the covers (K and a) according to Table 1.

Table 1. The coefficients to include the effect of height and topography on the wind velocity acting on the covers (CIBSE Guide A2-31).

Topographical condition K a Open Country – few windbreaks 0.68 0.17 Open Country – many windbreaks 0.52 0.2 Rough Country/Outskirts Small Town 0.33 0.25 City Centre 0.21 0.33

along the coastline). So the wind data together with the local topographical location forms an important basis to determine the required negative pressures under covers to overcome the effect of wind.

To overcome the effect of buoyancy, the minimum negative pressure required under the cover of a tank can be determined by using the following simplified equation (15): dPbuoyancy = p * g * h * dT / Toutside

(15)

where: p = the air density (kg/m3) g = the gravity constant (9.81 m/s2)

Figure 2. The required negative pressure under a cover for typical topographical conditions around wastewater treatment plants when only the effect of wind has to be negated.

h = the difference in height between where in-gassing atmospheric air reaches the under-cover headspace and where the out-gassing tank air reaches the atmosphere (m) dT = the difference between the liquid temperature and the outside temperature the tank (°C) Toutside = the outside temperature (°C) The influence of the temperature difference between the inside and outside of the tank over the pressure required to overcome the buoyancy effect is illustrated in Figure 3. The

Figure 3. Negative pressure under covers typically required to overcome the buoyancy effect.

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Displacement is the third force caused by air or liquid forced into the covered process units. The liquid level inside, for example, a sludge-holding tank changes due to differences in pumping rate while filling and emptying. The displacement amount needs to be compensated by the foul air extraction rate with a typical 25% safety margin (i.e. the ventilation system needs to have 125% of the filling rate allocated to negate out-gassing due to liquid displacement).

The overall negative pressure required under covers to eliminate foul air escape is determined by multiple site-specific conditions (wind, buoyancy and displacement and cover leakage area). The required negative pressure is typically at least -7 Pascals under low wind speeds (Degrémont Handbook, 2005) and more than -20 Pascal under more extreme wind conditions (Cadee and Wallis, 2007). Reducing the gaps in covers will have a direct positive effect in containing odours, eliminating fugitive emissions, as well as optimising air movements under the covers to provide the necessary ventilation.

MAINTAINING OPERABILITY Covers limit operator visibility and accessibility. Maintaining operability is usually the biggest hurdle to overcome when designing and installing covers.

Operators use their senses to assess the influent characteristics and the wastewater treatment performance based on factors such as turbidity, colour and smell, while the water levels can change diurnally, seasonally and during storm events. Moreover, scum accumulates in a routine fashion and diffused air creates recognisable patterns on the surface of aerated channels or tanks. So, when covers are installed over process units, an operator’s job can be made harder as the ability to inspect the process performance is typically restricted. Therefore, covers are easily subject to being partly left open. When covers are left open after an inspection or a maintenance activity, the ventilation system directly loses its effectiveness with the increased risk of odour nuisance as well as localised corrosion.

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“When installing covers, the operator’s ability to judge the wastewater treatment performance can be restricted” Maintaining the ventilation system effectiveness while maintaining operability requires cover designs specific for each process unit. When designing and implementing covers, not only are operator visibility and accessibility important considerations, so too are operator safety and cover durability. Poor cover design will result in unnecessarily large effort to gain access, hatches on covers being left open, and cover seals not being maintained or replaced. Poor cover design can also result in unsafe workplaces. Many types of cover are available, among them flat, barrel arch, removable and trafficable.

For the selection of covers many criteria must be considered, among them operability and maintainability, material selection, durability, OH&S issues, the environment below covers, corrosion, ventilation patterns and aesthetics.

Covers can be tested for how effectively they seal, even at the factory before installation on site. Table 2 shows the results of a factory test of a fabric cover used in the case study below. The negative pressure under the cover is measured under low or no wind conditions at different extraction rates. The negative pressure ranges in this case from -9 to nearly -130 Pascals when the extraction rate changes from 0.10 to 0.39 m3/s. The total leakage area (A) can be calculated using the previously mentioned Equation 2. When the periphery of the cover is known, the theoretical leakage gap (G) along the edge of the cover can be calculated as well: G = A/L/1000 = Qg / (Cd*(2*dP/p)1/2) / L /1000 (16) with the theoretical leakage gap (G) and the periphery of the cover (L) expressed in millimetres and metres, respectively.

In the example the periphery was 37.8m, which resulted in a theoretical

leakage gap of 1.1mm (see Table 2).

Typically gaps range from 0.5mm (very good sealing covers) to several millimetres (very poor sealing covers, or old covers with rubber seals exposed to wearing).

Factory testing can also help establish how effective covers are with an inspection hatch seal. This is to determine the influence of the number of inspection hatches of the overall Odour Capture Performance of a covered area. Factory testing can also help to determine the requirement and location of specific fresh air intake points to create specific ventilation patterns under covered areas. This is especially important for applications where not only odour containment is required, but also controlled ventilation to prevent zones with stagnant air (dead spots) to protect assets against corrosion.

PART 2: CASE STUDY The Cronulla Wastewater Treatment Plant (WWTP) is one of 30 wastewater treatment and water recycling plants in the greater Sydney area. It is owned and operated by Sydney Water, Australia's largest water utility. The plant is located on the southern end of the Kurnell Peninsula (about 18km from the city centre) and treats about 54 million litres of wastewater a day.

Like many of Sydney Water’s WWTPs, Cronulla WWTP is located in a sensitive environmental area. Concerns about the potential impact of odours on a new residential development near the WWTP led to a review of the site odour sources.

The odour was determined to be coming mainly from the primary treatment areas: inlet screening, grit tanks, primary sedimentation tanks (PSTs), PST launders, inter-stage overflow and pumping station areas. Sydney Water decided to develop and implement an odour control improvement project that would drastically reduce odour impacts. The Odour Management Program Alliance, consisting of Sydney Water, Lend Lease

Table 2. Results Air Leakage Performance Test (GTI, 2010).

Extracted airflow (m3/s)

Pressure (Pascals)

Theoretical leakage gap (mm)

#1

0.10

-8.9

1.1

#2

0.26

-88.9

1.0

Test

#3

0.38

-129.5

1.1

#4

0.39

-127.0

1.2

Average theoretical gap along the cover periphery (mm)

1.1

Table 3. The different type of covers and the number of inspection hatches.

Process unit

Cover design

Cover material

Trafficable

Cover type3)

Inspection hatches

Inlet channel

Flat

Aluminium

Yes

2

1

Around screen (stone trap)

Flat

Aluminium

Yes

1

5

Around screen

Flat

Aluminium

Yes

2

10 (2 per screen)

Barrel arch

FRP

No

2

16 (4 per grit tank)

Wet weather by-pass channel

Flat

FRP

No

2

4

PST inlet channel

Flat

Aluminium

Yes

2

24 (3 per channel)

Aluminium

Yes

1

16 (2 per channel)

Fabric

No

1

56

Grit tanks

PST drive platform

Flat (hinged)

1)

PSTs/Launders

Retractable fabric

PSTs/Launders

Flat

Aluminium

Yes

2

96

Launders outlet

Flat

Aluminium

Yes

2

16 (2 each channel)

Effluent channel

Flat

Aluminium

Yes

2

32

Fabric

No

1

2

2)

Wet weather storage area

Retractable fabric

Wet weather storage area

Flat

Aluminium

Yes

2

2

Interstage pump station

Flat

Aluminium

Yes

2

4

2)

1. See Figure 4.

2. See Figure 5.

3. Type 1 covers are easy removable, not fixed and used for frequent inspection, while Type 2 covers are permanent, fixed and not frequently used for inspection.

corrosive for materials such as concrete and steel. The minimum ventilation rate at a process unit is based on multiple criteria. These include the concentration of H2S, how well the covered area seals, the number of air changes per hour (ACH) and the air sweep velocity (m/s) in channels, while the ventilation rate per unit surface area (m3/m2/h) and extracted foul air to wastewater ratio (-) are used to verify the design.

and CH2M, worked to design, deliver and manage the project, which included three areas of focus related to odours: • Rehabilitating and protecting concrete structures below the covered areas to ensure intended asset life is achieved; • Covering the various treatment tanks to capture foul air while allowing the required operator and maintenance access to tank internals; • Constructing a new odour control facility to capture and treat the foul air.

The ventilation rates were selected to effectively capture odours and to keep the undercover environment less

“Unless odours are effectively captured with operator-friendly covers, money spent on odour treatment technology is wasted” Multiple different types of covers are used (see Table 3). Some areas require

regular access and need to be trafficable, while other areas do not require access or need to be trafficable. The covers may be divided into two types to set the minimum design requirements and to set guidelines for operation and maintenance activities after installation. Firstly, covers that are used for frequent inspection, not fixed and easy removable (type 1).

As these covers are frequently removed for inspection, each cover must have its own identity and a rubber seal. They are built to the needs of the operations crew and the standard practice is to inspect rubber seals every year and replace when necessary. Secondly, covers that are permanent, fixed and not frequently

Table 4. Design basis for the ventilation rate and the measured pressure under the covers after installation.

Process units

Sweep velocity (m/s)

Air changes (h-1)

Ventilation flux (m3/m2/h)

Gas to liquid ratio (-)

Measured pressure under cover (Pa)

Inlet channel

0.15

46

64

1.9

-5

Screens

NA

63

99

2.9

-5

Outlet channel

0.15

46

71

2.5

-6

Grit tanks

0.10

16

13

1.6

-9

PST inlet channel

0.15

34

34

1.0

-9

PSTs (up till Launders)

0.20

13

12

18.5

-21

PST Launders

0.10

33

26

6.8

PST outlet effluent channels

0.15

27–30

53–59

1.2–2.2

-21

Interstage overflow area

NA

8

16

3.7 - 5.5

-20

Interstage pumping station

NA

8

16

0.6

-21

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Technical Papers concentrations to areas with higher concentration and using inevitable openings as air intakes (e.g. access openings, motor drives or process units that are difficult to enclose completely) (see Figure 6). As fugitive emissions can contribute to a significant proportion of the off-site odours, a direct assessment of the actual leakage of fugitive emissions is necessary to eliminate surprises after project completion. All installed covers were smoke tested for quality control.

Figure 4. An example of a custom-designed aluminium cover system on the drive support platform at the inlet of the PSTs, with hand-operated winches to provide access for operators for regular cleaning. used for inspection (type 2). These fixed covers are not used as a general means of regular operator checks or entry for inspecting civil assets. The maintenance crew is required to remove the covers when required, and the standard practice is that any rubber seals, metal strips and permanent sealing are to be renewed when replacing these covers.

The design basis for the air extraction from the different process units is illustrated in Table 4. Design criteria were established to achieve near-complete odour capture, while creating enough ventilation under the cover to eliminate dead spots. The sweep velocity under the cover is typically around 0.10–0.15 m/s, while the air changes per hour are relatively high at the screening area due to the large leakage openings typical for screens and high hydrogen sulphide (H2S) concentrations. In the PSTs the sweep velocity of 0.20 m/s is relatively high as no coating is applied to the concrete of the PST tanks, and ventilation is here the main protection against concrete corrosion. The screening area contains screens with relatively large leakage openings around the screens and with existing covers that were not replaced for new covers, but only repaired and provided with new rubber seals.

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Consideration of the type of covers here included safety, manual handling requirements, confined spaces, airtightness, maintainability and cost.

For example, areas requiring frequent inspection for cleaning and inspection were fitted with aluminium covers with large hinged inspection hatches that are lifted with a custom-designed system of hand-operated winches, overhead pulley blocks and wire rope (see Figure 4).

The PSTs need to be taken out of service for regular cleaning, in which the scraper flights must be lifted slightly to allow wash water and residuals to drain.

Retractable fabric covers were selected for these large areas of the plant, where access and egress were critical (see Figure 5). This cover system consists of retractable fabric covers tensioned over supporting aluminium arches. The design includes inspection hatches as well as clear span guardrails that allow covers to be safely opened and closed without interference from standard guardrail supports. This installation was the first time this type of cover was used in Australia and was selected after extensive investigation by Sydney Water.

Other smart design features included bringing air with lower odour

The resulting pressure under the covers ranged from about negative 5 Pascals in the high ventilated screening area using existing covers, to more than negative 20 Pascals at the PST effluent channel and interstage pumping area with new covers (see also Table 3). With the newly designed ventilation system, the covers were able to maintain sufficient negative pressure under the covers at the large surface areas (PSTs, PST Launders and interstage storage area). These areas include the most turbulent processes with relatively high H2S concentrations emitted (Launders and PST effluent channel). This resulted in an overall Odour Capture Performance of about 98% when a topographical condition is assumed that can be defined as Open Country – many wind breaks.

To treat the extracted foul air from the covered sources, biotrickling filtration (BTF) technology was selected and implemented (Cesca and Kraakman, 2014). The reason for this is that an odour treatment system cannot always be given the highest priority by operators due to other priorities related to the primary purpose of the facility (conveying and treating wastewater). Therefore, a treatment system that is robust and simple to use is important. The BTF odour treatment system operates ostensibly with recycled effluent from the WWTP. Its odour and H2S removal efficiency during the summer of 2015 period was measured to be greater than 95% and greater than 99.8% respectively, while the residual H2S concentration and residual odour were, respectively, non-detectable (<50 ppbv) and less than 1,000 ou.

“From an Operations point of view, the access to the assets under the covers is great” In conclusion, an effective and sustainable odour control system has been installed at Cronulla WWTP for its main odour sources.

This is achieved not only by installing an effective and reliable odour treatment

THE AUTHORS Bart Kraakman (email: Bart.

Kraakman@ch2m.com.au) is Principal Process Engineer and Regional Technology Leader, Odour and Air Quality – Asian Pacific for CH2M in Australia. Bart has more than 20 years’ experience in the wastewater industry and specialises in biotechnology, air quality and odour control.

Josef Cesca is the Principal Technology Manager for CH2M in Australia and New Zealand (ANZ).

Josef has more than 25 years’ experience in the wastewater industry specialising in wastewater treatment, biosolids management and odour control.

Graeme Hamer is a Chemical Engineer at CH2M with approximately 10 years’ experience in air and odour issues, the majority spent on wastewater projects. Graeme specialises in modelling, including sulphide fate and ventilation modelling for sewers and dispersion modelling for air emissions.

Robert Aurisch is Sydney Water’s Plant Manager at Cronulla WWTP. He has more than 30 years’ experience in the chemical and wastewater industry, among them as Plant Manager of some of Australia’s largest wastewater treatment plants.

Figure 5. The PSTs before (top) and after (bottom) installation of the retractable fabric covers to provide a high odour capture performance while providing easy and proper access for operators.

REFERENCES AS/NZ 1170.2 (2002): Structural Design Actions – Wind Action.

system, but also by implementing a high level of odour containment designed to maintain operability.

Cadee K & Wallis I (2007): Odour Containment and Ventilation at Perth’s Major WWTPs, Water Journal, 34, 3, pp 54–60.

ACKNOWLEDGEMENT

Cesca J & Kraakman NJR (2014): Applying Odour Control Technology Using Reliability and Sustainability Criteria. Water Journal, 41, 4, pp 73-79.

The Authors wish to acknowledge the operators at the Cronulla plant for their diligence and support; the Odour Management Program Alliance (OMPA) staff, especially Peter Hordern and David Shukor, for their relentless efforts to improve cover designs and the testing of the covers implemented; and Brent Howe (GTI) for his support during the different stages of the project for the successful implementation of the retractable fabric covers.

CIBSE Guide A2-31 (1999): Guide A: Environmental Design. Chartered Institute of Building Services Engineers.

Degrémont Handbook (2005): 10th edition (in French).

Figure 6. Motor drives used as dedicated fresh air intake points.

GTI (2010): Results of Airtightness Test Performed on a GTI Retractable, Structurally Supported Cover.

Geomembrane Technologies Inc.

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WHEN ODOUR CONTROL IS NOT ABOUT ODOUR AT ALL A case study of hydrogen sulfides risk and mitigation I Evanson, A Whelan, M Vis, A Shammay

ABSTRACT Septicity in sewers and odour control at wastewater treatment plants have been the subjects of ongoing research across Australia and worldwide, with greater focus on odour impact and corrosion of sewer infrastructure. Less commonly reported, however, are the safety issues associated with hydrogen sulfide exposure to both workers and the public.

Taking Cleveland Bay Purification Plant (CBPP) in Townsville, Queensland, as an example, where hydrogen sulfide concentration in working areas exceeded 200ppmv, this paper explores issues relating to hydrogen sulfide exposure.

The CBPP upgrade resulted in the reuse of some infrastructure without consideration of the impact of highly septic influent. This resulted in heavy corrosion of assets, with some structures lasting approximately four years, and poor cover design leading to ambient hydrogen sulfide concentration in excess of 200ppmv in some areas.

CBPP has been operating with caustic dosing as a short-term hydrogen sulfide mitigation measure while long-term options are developed. In the short term, exclusion zones are being provided around the main affected areas, with selfcontained breathing apparatus required around heavily affected units. Procedural controls are also in place. The long-term works involve new covers, a new odour extraction and control system, and continuation of procedural controls.

INTRODUCTION Septicity of sewage, both in networks and flowing into treatment facilities, is generally on the rise; this is a result of a number of factors, including: 1.

2.

Transfer schemes to centralise and optimise the use of sewage treatment facilities by pumping flows to underutilised plants; Use of pressure sewer systems to collect and transfer sewage;

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3.

Reduced water consumption and resulting low sewer flows;

4.

The upgrade and re-siting of treatment facilities away from sensitive receptors, requiring the use of transfer mains;

5.

The ageing of sewers, allowing greater amounts of infiltration of sulfate-rich groundwater;

6.

The delivery of large pipelines for future flows that eventuate later than anticipated, or not at all.

The production of sulfide in rising mains and long flat gravity sewers is a long understood process, with the resulting gas phase concentrations readily predictable. Septicity assessments are routinely called for to quantify the liquid phase sulfide concentrations, as are odour assessments using dispersion modelling to establish odour impact on local sensitive receptors.

from gas exposure – even when there was no risk (or history) of odour complaints due to the location of the plant. Significant re-work of the facility was also required to resolve corrosion impacts.

HYDROGEN SULFIDE GAS

Hydrogen sulfide gas has a distinctive “rotten egg” odour and is emitted from wastewater containing soluble sulfide, which is generated through sulfate respiration and resulting septicity.

This can affect both human health and corrosion of assets.

In 2003, the World Health Organisation (WHO) published a study of the human health aspects of hydrogen sulfide. This report outlined the findings from many studies on animals and humans, as well as the findings from hydrogen sulfiderelated workplace safety incidents.

The report draws on approximately 150 reference papers from around the world.

Table 1 is a summary of its findings, as well as reported safe working levels of hydrogen sulfide.

Similarly, dispersion modelling to determine odour impact is also widely understood and legislated.

Table 1. Hydrogen sulfide health impacts versus However, if no odour concentration (adapted from WHO, 2003 and impact is modelled or Safe Work Australia, 2013). detected, potentially Hydrogen Sulfide Effect/observation due to the proximity Exposure (ppm) of the potential 0.008 Odour threshold complainants, this 2 Bronchial constriction in asthmatic individuals does not address 3.6 Increased eye complaints local health and safety or Increased blood lactate concentration, corrosion issues.

5–10 decreased skeletal muscle citrate synthase While the authors have experience at other sites, this paper will focus on Cleveland Bay Purification Plant (CBPP), located in Townsville, Queensland. CBPP required large odour control systems to protect personnel

activity, decreased oxygen uptake 10

8-hour time-weighted average (TWA) exposure limit

3.6–21

Eye irritation

15

Short-term exposure limit (STEL)

20

Fatigue, loss of appetite, headache, irritability, poor memory, dizziness

>100

Olfactory paralysis

>400

Respiratory distress

>500

Death

Corrosion effects vary with concentration and materials of construction; copper components are affected directly by hydrogen sulfide, by chemical reaction to form copper sulfide (black solid), whereas concrete corrosion is generally due to production of sulfuric acid by thiobaccillus bacteria, which oxidise hydrogen sulfide gas.

contaminant data to be obtained at CBPP, the design of the odour control system was based on the hydrogen sulfide concentration collected from one of the upstream PSs, because this data was available at the time. Use of this raw data did not account for the sulfide generation in the two rising mains feeding CBPP.

CLEVELAND BAY PURIFICATION PLANT

Although at the time it was recognised that the eastern and western rising mains had different properties, it was assumed that the data collected at one of the upstream PSs would be representative of what would occur onsite at CBPP.

Cleveland Bay Purification Plant (CBPP) was originally constructed in the 1980s and upgraded in 2008 to a 126,000 EP MBR/BNR (equivalent person membrane bioreactor/biological nutrient removal) plant.

The plant upgrade included, among other items: • New primary and secondary screens; • Modification of an existing final settling tank to a new primary tank; • New MBR/BNR plant built inside a second existing modified final tank.

The plant was constructed far from residents, on salt marshes. During the upgrade the inlet works (excluding the aerated grit tanks), raw sewage channels, primary tank launders and secondary screens were covered and vented to an odour control facility (bark biofilter).

Odour to surrounding receptors was not considered an issue, mainly due to the plant odour management measures and the remote location.

CBPP is predominantly fed from two rising mains; the western rising main is approximately 5.5km long and is fed from Cluden Pumping Station (PS). The eastern rising main is approximately 17km long and is fed from Bellview PS. There is currently no dosing within the upstream network or at CBPP itself to address septicity issues. Both rising mains are subject to saltwater intrusion, with parts of one also suffering from infiltration contaminated by acid sulfate soils.

USE OF REPRESENTATIVE DATA FOR DESIGN

During the design phase of any plant upgrade, contaminant data, including hydrogen sulfide, should be sought to enable the odour control facilities to be designed. When an existing facility is available for sampling, site-specific data should always be preferred.

Although the presence of an existing plant would have enabled site-specific

The upstream network feeding CBPP is subject to saltwater and groundwater intrusion, which elevates the wastewater sulfate concentration. While the increased concentration of sulfate does not materially affect the rate at which sulfide is produced, it does change the upper limit of sulfide that can eventuate.

Generally the maximum sulfide concentration that can be obtained is dictated by the sulfate available to convert into sulfide – this being 16 to 18mg/L total soluble sulfide, based on a normal domestic wastewater sulfate concentration.

By increasing the sulfate available for conversion to sulfide this upper limit is increased, as occurs at CBPP. It is not uncommon for a soluble sulfide concentration of 25 to 35mg/L to occur in incoming sewage, especially from the Bellview PS rising main.

Considering that nearly 95% of the sulfide load arriving at the site is by generation in the rising main from Bellview PS, the assumption that Cluden PS data would be representative was a critical error.

The use of this data led to the assumption that septicity was not a significant issue at CBPP, and that design concentrations for hydrogen sulfide should be 10ppmv in the gas phase, approximately 5% of what was measured subsequently on site.

HYDROGEN SULFIDE EMISSIONS FROM UNCOVERED TANKS AND CHANNELS

The accepted methodology for determining which tanks require gas containment covers and extraction on a treatment facility is based on dispersion modelling. Tanks are “covered” in the model, reducing the odour footprint until surrounding sensitive receptors

are outside the impact area (2.5ou (odour units) on a one-hour average, 99.5 percentile basis for Queensland).

While this methodology is acceptable in establishing the gas containment and control required for mitigation of off-site odour impact, it is not suitable for establishing covers and containment to prevent localised hydrogen sulfide exposure, which cannot be easily predicted. The rate at which hydrogen sulfide is emitted from the liquid surface is a function of liquid phase sulfide concentration, pH, temperature and turbulence (which affects gas-liquid mass transfer rate of the contaminant). All of these factors can be estimated, allowing a gas phase concentration above the liquid surface to be estimated.

However, the concentration of hydrogen sulfide gas which this then produces in the working environment local to the equipment is dependent on the dispersal of the gas into the work area, which itself is a function of a number of other factors. These predominantly include: • Gas buoyancy (temperature vs ambient); • Local wind conditions; • Topography of above-ground structures (producing vortices and other micro-meteorological conditions).

The inherent variability in these factors makes accurate predictions of gas phase concentrations in working areas difficult to achieve, even with mainstream dispersion models.

In cases where the liquid phase soluble sulfide level is predicted (or measured) to be high, and/or the wastewater turbulence in that area is elevated, serious consideration should be given to the risk of hydrogen sulfide exposure.

A high degree of scrutiny should also be applied to the resulting plant design.

At CBPP, the only areas left uncovered in the preliminary treatment area were the aerated grit tanks, discharge weirs and primary screens. During the design phase there was no perceived reason to cover them and they were not included as part of the plant upgrade, as septicity was not considered an issue.

During the plant audit conducted

by MWH, a hydrogen sulfide logger was placed at head height at the downstream end of the tank, on the walkway above

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Technical Papers The concrete pipeline and intermediate wet wells downstream of the now converted primary tank at CBPP suffered extreme corrosion. Concentration of hydrogen sulfide gas in one of the wet wells was logged during the plant audit (see Figure 2). The measured concentration exceeded the range of the 0-1,000ppmv instrument, with the instrument reading a maximum of almost 1,400ppmv.

Hydrogen SulďŹ de Concentration (ppmv)

The effect of septicity, hydrogen sulfide gas and resulting corrosion had not been considered when the pipeline had been re-used to transport primary effluent, so suitable corrosion-resistant lining had not been incorporated into the design.

Figure 1. Concentration of hydrogen sulfide gas in ambient air in working areas. the discharge weir. Another hydrogen sulfide logger was placed in working areas around the covered secondary screens, downstream of the primary sedimentation tank. The results are shown in Figure 1.

Concentration of hydrogen sulfide gas was found to peak regularly above 150ppmv, almost reaching 200ppmv in the ambient atmosphere on the walkway above the grit tanks. Concentrations of hydrogen sulfide exceeding the STEL were also measured almost every day in the working areas around the secondary screens (this is further discussed in the next section). It is worth noting that the gas concentrations in the breathing zone vary significantly over short distances, making consideration of the tasks in that area and the relative exposure crucial (e.g. crouching to take a liquid sample as opposed to standing/traversing the area).

While the grit tanks did not require covers based on an off-site odour impact assessment, covers were required based on the local hydrogen sulfide levels and risk to personnel.

PROTECTION OF EQUIPMENT FROM SULFIDE-BASED CORROSION

configuration and role. Re-using the tanks significantly reduced the overall plant capital cost.

When re-using equipment in a new process configuration the materials of construction should be rigorously interrogated to ensure that they are suitable for the new duty. Concrete pipes that were once used to transport final effluent may be hydraulically capable, but may not be suitable for the transport of sulfide-laden primary effluent rather than the (sulfide-free) final effluent they were originally designed for.

The pipeline failed within a short period (approximately four years) after its use was changed, causing subsidence along the pipeline route. Townsville City Council immediately replaced the failed pipe with a suitable polymerbased pipe and instigated a review of the surrounding pipes and structures.

The majority of pipes were found to be in poor condition, with serious corrosion up to and beyond the reinforcing steel (Figure 3). The pipes have since been refurbished and fitted with corrosion resistant liners.

Some intermediate wet wells had been lined with an epoxy type coating to protect against concrete corrosion; however, the coating had failed, with large sections delaminating from the concrete surface. Corrosion in these wet wells was significant, exceeding 25mm.

Hydrogen SulďŹ de Concentration (ppmv)

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The re-use of existing plant assets when upgrading facilities is not only a useful option to have, but also a necessity in the current economic climate.

At CBPP, existing final settling tanks and associated infrastructure were reused in the upgrade in a changed process

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Figure 2. Concentration of hydrogen sulfide gas in wet well downstream of primary tank.

Figure 3. Camera footage showing typical corrosion of remaining pipe and exposed re-bar.

DESIGN OF APPROPRIATE GAS CAPTURE AND CONTAINMENT

The use of covers to prevent or reduce odour emission from tanks is a wellunderstood and accepted practice.

The capture rate of gas is a function of the negative pressure achieved under the covers.

The negative pressure required to prevent fugitive emissions is a function of cover size, type and wind loading. The negative pressure that can be sustained under odour control covers is a function of: • Negative pressure provided by the odour control system fan at the extraction point; • Number of extraction points, and dispersal over the cover; • Type of cover, number of cover joints, penetrations and cover flexibility that define the leakage rate;

the free area between the atmosphere and the tank air space volume, the higher the extraction required.

channels and Rotary Sludge Thickener (RST) building. The hydrogen sulfide-rich ambient atmosphere had caused damage to:

It is worth noting that 100% odour capture is rarely achieved by covering process units, as this is not economically achievable (i.e. too high a ventilation rate would be required for perfect sealing). A static negative pressure of 25 Pa under covers is generally accepted to achieve an odour capture rate of between 99 to 99.9% (Cadee et al., 2007). Depending on the nature of the covers, a 0.15mm gap around the cover perimeter can account for approximately 10–20Pa pressure loss, which can be the difference between good foul air capture and poor foul air capture.

1.

Air conditioning units;

2.

Busbars (reported as discoloured);

3.

VSD (variable speed drives);

4.

Penstocks, including shafts and spindles;

5.

Copper water pipework.

The audit at CBPP found that none of the covered areas sustained any significant negative pressure. Average pressure differentials, where measured, varied between -0.3Pa and -5.8Pa. These readings did not allow for effective capture of gas with varying wind and solar conditions. The reasons for these low recorded pressure differentials included: I.

Poor sealing of covers;

II.

Small number of extraction points and/or selection of extraction point location; of underground ductwork and/or build-up of condensate;

IV.

Use of porous “matting” as cover material.

If a design negative pressure of -150Pa is assumed at the extraction point, then the negative pressure sustained under the covers is dependent on the free area available for air ingress from the atmosphere (or other process area), and the gas flow rate through that space.

As the free area is decreased, the gas velocity, and therefore pressure drop, is increased, leading to a higher negative pressure being sustained under the covers (Hadiardja et al., 2010).

The achievable negative pressure is dependent on both the ventilation rate and the gaps between the cover sections, with a high sensitivity to the gaps between the cover sections and the number of penetrations within the cover. The higher

Similar issues with gas leakage, elevated hydrogen sulfide concentration, and corrosion-related damage to mechanical and electrical equipment was noted across the site, specifically around the inlet works, screened sewage

• Degree of interconnection of process areas under the covers, allowing interprocess distribution of air.

Given the issues with the initial selection of design data, and resulting assumptions, an inappropriate gas treatment technology was selected. Gas was treated at CBPP by a “soil bed’’ type bark biofilter. This type of system was not suitable for the following reasons: I.

They are generally limited to treatment of hydrogen sulfide gas concentrations below 30ppmv with stable gas flowrate and operating conditions at site;

II.

The 316 stainless steel fans are on the ‘dirty gas side’ inlet to the unit and not suitably protected against hydrogen sulfide based corrosion, leading to failure within four years;

III. The

‘clean’ air discharge is at ground level, so high concentration gas passing through the unit is a potential hazard for operators at head height;

III. Use

The effects of this poor capture of gas were considerable. Hydrogen sulfide concentrations surrounding covered areas were elevated above the STEL due to leakage of hydrogen sulfide gas and mechanical equipment prematurely failed due to corrosion. The measured hydrogen sulfide concentration around the covered secondary screens shown in Figure 2 shows the effect of not achieving any negative pressure, with hydrogen sulfide leakage increasing ambient hydrogen sulfide gas concentration. Levels regularly exceeded the STEL of 15ppmv, with peaks as high as 71ppmv. Operations reported that the mechanical resilience of the screens was low, with bearings failing regularly due to corrosion.

• Air inlet configuration, e.g. provision of weighted air inlet dampers or grills;

SELECTING APPROPRIATE ODOUR CONTROL TECHNOLOGY

IV.

CBPP grounds are known to be infested with termites, leading to degradation of the bark and shortcircuiting of the bed.

SHORT- AND LONG-TERM MITIGATION OPTIONS All of the issues related to hydrogen sulfide gas, whether it is corrosion or exposure related, can be mitigated by careful consideration in design. The key point to remember is that, without site-specific data, any solution has a high risk of failure.

Should septicity and its effects not be considered, or septicity become an issue on a site, there are both short- and longterm mitigation options available. These options will be site-specific, and at CBPP the following was conducted.

SHORT-TERM MITIGATION

Short-term covering and ventilation systems can be provided; however, the lead time for such equipment is typically long. Remaining options generally fall into two categories: chemical dosing and/or procedural.

Many chemicals are available for control of septicity; however, when off-site dosing

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Technical Papers • Continuation of site procedural systems as per short-term mitigation; • Installation of suitable gas containment covers and ventilation rates to ensure required capture rates are obtained.

Target negative pressure under covers of (at least) -25Pa to ensure effective gas capture in varying wind and solar conditions; • Provision of infrastructure for temporary caustic dosing for maintenance activities involving cover removal; • Replacement of bark biofilter with a suitable gas treatment technology.

CONCLUSIONS & LESSONS LEARNT

Figure 4. Exclusion zones at CBPP, where enhanced PPE and procedural requirements are in force until suitable containment covers and ventilation are commissioned. is not possible the options are significantly reduced. Magnesium hydroxide, for instance, requires approximately 20 minutes to effect the desired increase in wastewater pH. Dosing at the inlet works will not have any immediate effect.

Chemicals that have fast or instantaneous effect on the wastewater – ferric, ferrous or strong alkalis such as sodium hydroxide (caustic) – are suitable.

Ferric and ferrous (collectively known as iron) salts convert soluble sulfide to insoluble sulfide, thereby removing it from solution. Caustic dosing increases pH, locking the soluble sulfide in solution as HSand S2- ions (depending upon target pH), preventing release to the atmosphere.

In the case of CBPP, an options study identified caustic dosing to elevate pH as the cheapest option, as being easy to control, and having potential benefits to the treatment process. Iron salts, however, were expensive and would have had adverse impacts on solids production, alkalinity and the downstream membrane plant.

Caustic dosing with a pH set point of 8.6 was predictable, easy to control and reduced gas phase concentrations across CBPP to acceptable levels; albeit at significant short-term operating cost.

Site-specific procedural systems were also put in place to ensure risks of exposure are low. These included: • Regular communication;

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• External safety system review and advice; • Inductions/training; • Exposure analysis; • Use of personal protective equipment (PPE), including gas monitors; • Risk assessments; • Permit to work system and additional procedures; • Access restrictions; • H2S personnel exclusion zones, to include any area of the plant with an atmospheric concentration at or above 10 ppmv H2S; • Exclusion zones (Figure 4), including areas of the treatment plant where respirators and/or two-person working were mandatory; • Self-contained breathing apparatus correctly worn by all persons in areas where work is being undertaken and where H2S gas is known to be present at an atmospheric concentration of >15 ppmv H2S; • Job health assessments for work in exclusion zones.

Although dispersion modelling and odour control design for mitigating off-site odour impact are commonplace, the risk of developing a localised high concentration of hydrogen sulfide on treatment plants is often ignored or not considered. Should this high concentration eventuate, the effects can be profound for both personnel and equipment.

CBPP is an extreme example, due to the influent conditions; however, it is by no means unique. Increasing septicity and hydrogen sulfide concentration in catchments and at treatment plants is an ongoing and worsening issue. Since CBPP was audited, two other plants in Queensland have been found to have an unacceptable concentration of hydrogen sulfide in work areas near to or on inlet works structures.

Whether designing new or upgrading existing facilities, specific care and consideration should be given not only to the off-site impact of odour, but also the on-site impact of specific compounds such as hydrogen sulfide gas.

Other key lessons learnt include: 1.

Site-specific data should always be sought, and the method of data/sample collection should be considered. Liquid phase sulfide monitoring is notoriously difficult due to sample degradation.

2.

Performance guarantees on new or upgraded works should include localised hydrogen sulfide concentration compliance with relevant safe workplace legislation, and cover capture rates.

3.

Always interrogate designers’ selections of plant and equipment – and pay specific attention to materials

LONG-TERM SOLUTIONS

While pH modification by caustic dosing is an effective control method, the costs for its continuous use are generally prohibitive.

In order to protect personnel and assets, more permanent solutions are being implemented including:

of construction when either building new plant or reusing existing assets.

4.

Never assume that, because there is a containment cover in place, the surrounding ambient atmosphere is safe. Covers rarely achieve 100% capture at normal extraction rates.

Regular checks on negative pressure to ensure containment should be made.

5.

On infrastructure with septic inflow, hydrogen sulfide exposure risk assessments and safe work methods should be drafted and employed.

6.

The use of exclusion zones where entry is only permitted with appropriate PPE should be considered when appropriate containment covers are not installed.

7.

8.

Where septicity is a known issue, the use of personal hydrogen sulfide detectors should be mandatory.

Caustic dosing on pH feedback control is a very effective quick fix’, albeit with significant operating costs, while either more permanent facilities are being installed or covers are opened or removed for maintenance.

ACKNOWLEDGEMENT The Authors would like to acknowledge Townsville City Council in Queensland for its support and for its contribution to this article’s contents.

THE AUTHORS Dr Ian Evanson (email: Ian.Evanson@mwhglobal. com) is a Principal Odour Specialist with MWH. He has over 17 years of experience working within the odour control, wastewater design and gas scrubbing industries and has designed, commissioned and installed numerous successful projects throughout Australia, the UK and the Middle East.

Anna Whelan has been a Process Engineer with Townsville City Council for over 10 years. Anna has been involved in the upgrade of the Cleveland Bay Purification Plant since its inception in 2011.

Mark Vis is the Manager of Wastewater Operations for Townsville City Council, managing wastewater treatment, wastewater reticulation, trade waste, biosolids reuse and effluent recycling.

Ari Shammay (email: Ari.T.Shammay@mwhglobal. com) is a Senior Process Engineer with MWH and is currently studying a PhD in Odour Abatement in Sewer Networks at UNSW.

REFERENCES Cadee K & Wallis I (2007): Odour Containment and Ventilation at Perth’s Major WWTPs, Water Journal, 34, 2, pp 54–60.

Hadiardja G, Wilkie A & Evanson I (2010): Beyond Air Exchange Rates – Designing for Odour Containment. AWA Odour Specialty Conference.

Safe Work Australia (2013): Workplace Exposure Standards for Airborne Contaminants. Safe Work Australia. www.safeworkaustralia.gov.au Townsville City Council (2014): CB0063 Hydrogen Sulfide Gas Management Procedure.

World Heath Organisation (2003): Hydrogen Sulfide: Human Health Aspects.

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TRADING IRRIGATION WATER FOR HYDROELECTRICITY WATER TRADING

Trade prohibitions and possibilities in the East Kimberley, Western Australia M Hartley

ABSTRACT The current regulatory framework governing water trading in Western Australia (WA) restricts transfers between categories of licences. In water-dry and water-wet areas alike, this restricts the trading of irrigation water for alternative purposes, such as power generation (hydroelectricity). This article questions the efficacy of these restrictions and uses the East Kimberley as a case study in the broader WA water law context. It contends that the framework would be better construed if water entitlements can be traded without a ‘like for like’ restriction. The framework is guided by the policy objectives of efficient use and management, trade and competition for water resources, and reducing restrictions to water trade is vital to achieving these objectives.

Keywords: Western Australia; water law framework; water allocation; water trading; water markets.

INTRODUCTION The East Kimberley region of Australia supports an often cited but little understood irrigation industry in the form of the Ord Irrigation Scheme (OIS).

The OIS currently comprises Ord Stage 1, opened in 1963, and the Ord Stage 2 Expansion Project, with Stage 2’s first sorghum crop having recently been planted in the Goomig Farmlands.

The OIS is in the development phase for Ord Stage 3, which will see the scheme cross jurisdictions from WA to include the Northern Territory, and continue to expand the western flank of the proposed national ‘food bowl’ of the north.

The OIS is a surface water irrigation system strategically focused on harnessing the vast water resources flowing from the wet season and utilising that water for efficient large-scale crop production. The result is an economically viable region and a booming export market domestically and to Asia for the

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supply of produce including chickpeas, cotton, beans, chia, mangoes, sugarcane and sandalwood. Key water stakeholders in the region include the township of Kununurra, the Ord Irrigation Co-operative (OIC), hydroelectricity company PacificHydro, the Argyle Diamond Mine, and Kimberley Agricultural Investments (KAI).

The region is not ‘water-dry’, but faces growth in demand for its water resources, with development propelled by statewide and overseas investment in Ord Stage 2. With multiple stakeholders and multi-million dollar projects as its drivers, the region’s potential to engage in a water market is increasing. However, the ability of stakeholders to trade is limited by the Rights in Water and Irrigation Act 1914 (WA) (RiWI Act) and the Ord Surface Water Allocation Plan (OSWAP), which both place tentative and arbitrary restrictions on the ability to trade water between categories of licences (DOW, 2013).

A key illustration of this is whether OIC and KAI can trade their irrigation

water allocations to PacificHydro for the purposes of hydroelectricity.

The question is particularly relevant as irrigation stakeholders risk losing unused water entitlements, which has an adverse impact on long-term planning and investment. This is an area of contradiction and ambiguity, given the broader policy structure that seeks to govern water use and trade in the state.

This article questions the efficacy of restrictions placed on trading irrigation water for alternative purposes, such as hydroelectricity, and uses the East Kimberley as a case study in the broader WA water law context. Section 1 provides a brief background to the East Kimberley and its key stakeholders.

Sections 2 and 3 examine the legal and policy frameworks respectively, to analyse how they permit or prohibit water trading in WA broadly and in the East Kimberley specifically. The focus is on temporary trades, although the regulatory framework permits both permanent and temporary trades.

Throughout, the article scrutinises the

Sandalwood plantations in the East Kimberley region.

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Technical Papers large-scale irrigation entities (OIC and KAI), mining ventures (Argyle Diamond Mine) and the environment each have their own water requirements.

Section 4 reaches the conclusion that the WA water law and policy framework would be best construed if water entitlements can be traded without a ‘like for like’ restriction, so that irrigation water can be traded for purposes that include hydroelectricity.

This is a superior construction of the law because the frameworks are guided by the policy objectives of efficient use and management, trade and competition for water resources, and reducing restrictions to water trade is vital to achieving these objectives. The alternative interpretation – that transfers are only permissible between like for like licensed users – serves no identifiable, meritorious economic policy objective.

Instead, it concentrates power over water use in the state water bureaucracy, a perverse outcome in the absence of empirical market failure.

The region currently experiences only a limited water market, explained in part by its ‘water-wet’ nature, but also the legal and policy framework that limits trading between categories of licences. However, the region is expected to undergo growth and demand for its water resources as the land is put to more productive agricultural use with the completion of OIS Stage 2 and commencement of Stage 3. These drivers increase the need to question the current regulatory framework that limits water trading between different stakeholders and to argue for alternatives.

SECTION 1: BACKGROUND TO THE EAST KIMBERLEY AND ITS STAKEHOLDERS The East Kimberley comprises the northern-most section of WA, taking in the townships of Kununurra, Wyndham and Aboriginal communities such as Kalumburu. The local government is the Shire of Wyndham East Kimberley, which covers an area of 121,000km2 and serves a population of just over 8,600 people (MacroPlanDimasi, 2013). The region has seen various stages of expansion, beginning with the development of the Ord River Irrigation Area in the 1960s and facilitated by an approach to irrigation based on three interconnected components: dams (the Argyle Dam, constructed with a price tag of US$11 million, and the Kununurra diversion dam); channels and supply lines (to Packsaddle and Ivanhoe in Stage 1, and Weaber Plains – now Goomig farmlands – in Stage 2) (Waitt, Lane and Head, 2003); and the drains used to manage tailwater and control irrigation runoff.

3). The Argyle Dam and monsoonal rain systems create an annual reliability of 95% for water supply (DOW, 2013).

There are competing interests at play in the water market of the East Kimberley. The towns, Aboriginal communities, the State Water Corporation, power generators (PacificHydro) and distributors (Horizon),

SECTION 2: LEGAL FRAMEWORK The legal regulation of water use in the East Kimberley evidences a simultaneous top-down but somewhat decentralised approach to water management. The regulation is divided between the RiWI Act, the Water Agencies (Powers) Act 1984 (WA) (WAP Act), the Water Services Act 2012 (WA) (WS Act) and the various regulations therein. With the exception of water extracted for stock and domestic purposes (unlicensed), the Department of Water (DOW) confers licences to stakeholders for specific purposes (for example, irrigation or hydroelectricity) and the licensee is then subject to the guiding legislation.

As examples, the Water Corporation has a licence (although no allocated water) to provide water for hydroelectricity, whereas the OIC has a licence for the purposes of water distribution and supply for irrigation use. These are not ‘like for like’ licence categories and the legal framework places ostensible restrictions on trading between them.

Large-scale water licensees such as the Water Corporation and OIC are also water service providers (WSPs). This makes them subject to the provisions of both the RiWI Act and the WS Act. The RiWI Act licence (section 5C) details their total water allocation over the life of the licence (usually 10 years), while the WS Act confers a licence to supply water to customers under Part 2 Division 2. In practice, this means that the Water Corporation and OIC are conferred a licence for a total volume of water (for

example, 335GL/yr in the OIC) and provide it to their customers on an annual basis. The customers of the Water Corporation are primarily townships, while individual irrigators comprise the customer base of the OIC. The co-operative arrangement for large-scale water licences (evident in the OIC) is neither uncommon in WA nor unique to the water industry (DOW, 2007; Australian Co-operative Development Services Ltd). Individual irrigators, as members of the co-operative but termed customers under the WS Act, apply to the OIC for the right to use an annual volume of the total amount of licensed water. The arrangement facilitates administrative efficiency from the DOW as the OIC manages the individual users, ostensibly similar to a decentralised structure based on a degree of self-management.

An important ramification of this arrangement is that OIC members are not conferred individual water access entitlements because the OIC holds the licence for the bulk volume. The nature of section 5C RiWI Act licences in surface water systems is such that a licence confers a long-term right to the licensed volume of water, but the actual allocation fluctuates annually, based on rainfall and water availability in the dams.

Thus, licensees such as the OIC may not receive an annual allocation of their full 335GL/yr entitlement and this is reflected in the volume of water annually allocated to individual members of the co-operative.

The RiWI Act permits both the permanent or temporary trade (termed ‘transfer’) of water entitlements, with eligibility to hold a licence being a precondition to its trade (sch 1 cl 29(1)). The Act allows for the transfer of either the whole licence allocation or the water entitlements held under the licence.

There are three important exceptions to water transfers that preclude the operation of an open market, further to the administrative requirement that the Minister must approve all water transfers (sch 1 cl 31(1)): 1.

sch 1 cl 29(1): transfers are restricted to people who hold or are eligible to hold a “licence of the same kind”;

2.

sch 1 cl 29(1)(2): local by-laws may prohibit the transfer of licences of a particular kind;

3.

sch 1 cl 38(1): the Minister can enter into a transfer with a licensee if the

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interaction of these frameworks to expose how they can be utilised in a way that facilitates water trade for alternative purposes.

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whole or part of a licence is not being used, or if the licence is not being used for the purpose for which it was conferred.

The first and third exceptions are of critical importance to this article’s argument, that water licensed for irrigation use should be transferrable to other purposes, such as hydroelectricity.

Plainly, irrigation and hydroelectricity are not ‘like for like’ water uses or categories of licences. The restriction on this form of trade is a legal restriction arising from the Act. Notably, however, it is not a complete restriction; transfers are not restricted where people are eligible to hold a similar licence. Under this interpretation it could be possible for stakeholders in the region to trade unused water entitlements from an irrigation licence if they are eligible to hold a licence for the purposes of providing water for hydroelectricity.

There are numerous circumstances under which a person may be eligible to hold a RiWI Act licence. WSPs hold their licences pursuant to both RiWI Act and WS Act provisions. Under the RiWI Act, WSPs are authorised to engage in the specified land or water activities provided that they have satisfied the

Minister that the WS Act recognises their ability to carry out certain services (RiWI Act, sch 1 cl 3(d)). The WS Act licence may include conditions that permit rights of entry to land and the inspection, monitoring or maintenance of works (WS Act s 103). Alternatively, landowners may agree in writing to permit stakeholders like co-operatives entry to the land to carry out the work permitted under the licence (RiWI Act sch 1 cl 3(b)).

In any case, eligibility to hold a licence for the purposes of hydroelectricity or irrigation and thus trade between ‘like for like’ licences is not an insurmountable hurdle. However, the RiWI Act’s passive restriction on trading between categories of licences does create impediments to the efficient operation of a market, particularly if the primary means of overcoming them is through applying for another licence.

It is also arguable that precluding trade between categories of licences is not a beneficial outcome. This is particularly so if the restriction results in licensees using their entitlements inefficiently in order to avoid losing them under the state’s recoupment policies (examined below). A further question is whether, given the third exception above, allowing the Minister to

The Ord River Dam at Kununurra in Western Australia.

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have a monopoly on these kinds of trades presents good public policy in a region set to further expand and place greater reliance on its water resources.

SECTION 3: POLICY FRAMEWORK Understanding the policy framework is essential to unpacking the utility of legally restricting water trade between different categories of licences. WA is heavily reliant on its water policy framework, potentially as a result of the continued existence of the outdated RiWI Act. The policies of primary concern to the current debate are: the OSWAP; Water Entitlement Transactions for Western Australia (Trading Policy) (DOW, 2010); the Management of Unused Licence Entitlements Policy (Unused Licence Entitlements Policy) (Water and Rivers Commission, 2003); and the Policy on Water Conservation/Efficiency Plans (WCEP Policy) (DOW, 2009).

OSWAP The OSWAP aspires to guide water allocation in the East Kimberley, but particularly over the Ord River. Like all WA water-sharing plans, the OSWAP is non-statutory and represents a policy directive that can be overturned by the DOW or the State Administrative

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The OSWAP indicates that water is available for licensing in four of the five sub-areas covered by the plan (DOW, 2013). The Main Ord sub-area has a further 242GL/yr available for licensing, in excess of the 335GL/yr allocated to OIC (the total allocation limit is 750GL/ yr) (DOW, 2013). Clearly, water shortage is not a primary concern for the region.

Rather, with water availability so high, large-scale irrigators are now questioning how best to utilise excess water so as not to use it inefficiently or lose the portion of an entitlement that is not immediately needed to fulfil crop requirements. This is particularly relevant in the circumstances of the East Kimberley, where there is no active market for trading water for like purposes and licensees are restricted from trading between licence categories.

The OSWAP provides an active prohibition against trading water entitlements for electricity or environmental purposes (DOW, 2013).

This is in contrast to the passive restrictions contained in the RiWI Act described above. However, the policy framework interactions mean that the question of whether, for example, an irrigation co-operative can trade its water to a power generator, is a moot question. Specifically, the Trading Policy, Unused Licence Entitlements Policy and WCEP Policy each provide reasons supporting this type of trade in the East Kimberley, and throwing into doubt the apparent restrictions contained in the RiWI Act and OSWAP. Trading Policy The Trading Policy differentiates between trades and transfers on the basis of whether the new users’ extraction will be at the same

location (transfer) or a different location (trade) (DOW, 2010). It is likely that any transfer of water from one category of licence to another would be considered a ‘trade’, on the basis that the water would be extracted from a new location for a new purpose. The Policy – as opposed to the RiWI Act – restricts transfers or trade across separate sub-areas (first provision), as well as limiting them to the volume of water that remains unused by a licensee on an annual basis (DOW, 2010).

The legal implications for this are unclear, although it is likely that the DOW would be guided by the Policy and so preclude trade across separate sub-areas.

Nevertheless, any users operating in the same sub-area would not be restricted by the first provision. It is important to note that the Policy contains no explicit provisions that preclude trading between categories of licences. Instead, and when read in conjunction with the Unused Licence Entitlements Policy and WCEP Policy, it ostensibly contains provisions that facilitate this type of trade.

Further, and at a philosophical level, the issue is one of bureaucratic control versus market mechanisms.

It is arguable that greater economic benefit in the East Kimberley is derived from permitting trade between licence categories because entitlements can then be utilised for different purposes and not risk being recouped, creating a free-flow of water rights between users. It is further beneficial given that, currently, entitlements may be recouped on the basis that they are not being used but, simultaneously, there is only a limited market to trade like for like licence allocations. Permitting trade between licence categories thus represents a more administrative and resource-efficient outcome.

Unused Licence Entitlements Policy The application of the Management of Unused Licence Entitlements Policy is at the heart of the argument towards permitting trade between different categories of licences. Worldwide, this policy is colloquially termed ‘use it or lose it’ (Kwasniak, 2010). In a worst-case scenario its effect is to scare licensees into using their whole annual entitlement or risk the Minister recouping the portion of a licence that remains unused. It has previously been argued that the policy’s application and effect of discouraging water frugality is one of the primary measures constraining efficient water use in WA (Hartley, 2014).

Notwithstanding, the Management of Unused Licence Entitlements Policy states that it “will not tolerate the wasting of water” (Water and Rivers Commission, 2003). It creates a ‘stick’ approach to management in that it threatens the cancellation of licences to licensees who waste water in order to use their full entitlement and avoid its full or partial recoupment. Simultaneously, however, it adopts a “carrot” approach and incentivises efficiency by permitting the on-sale or trade of water that is saved due to conservation or efficiency measures and becomes superfluous to a licensee’s requirements (Water and Rivers Commission, 2003).

This framework permits licensees to engage in water conservation measures and trade the unused portion of its licence entitlement. The trade it conducts must be compliant with the RiWI Act requirements but, as argued earlier, the eligibility requirements can be overcome by obtaining a new licence or land-owner approval to utilise the water for a different purpose. This approach may be particularly palatable for irrigation co-operatives because the policy expressly states that unused entitlements resulting from investment in water use efficiency will not be recouped. These stakeholders are arguably the best positioned to improve their efficiency but are also a stakeholder that water has traditionally been recovered from, because taking water from town suppliers is usually a last resort (Water and Rivers Commission, 2003).

The RiWI Act and Management of Unused Licence Entitlements Policy can also be invoked to permit the Minister to enter into a transfer with any stakeholder for the unused part of a licence (RiWI Act sch 1 cl 38(1)). This provision differs from a typical recoupment on the basis that the Minister must pay consideration for the transfer (RiWI Act sch 1 cl 38(2)(b)). The application of this clause and its history of use in WA is unclear and tentatively questionable, particularly in light of figures demonstrating that recoupment measures have historically been underused (Hartley, 2013; Skurray, Pandit and Pannell, 2012). Its existence, however, is illustrative of the range of measures permitting trade in WA that stakeholders can rely on if they were to consider trading between licence categories.

The Policy also affects WSPs. It implies that water entitlements unused

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Tribunal. This would usually occur in circumstances where a licensee is dissatisfied with a licensing decision under the plan. WA’s non-statutory plans are also non-compliant with the National Water Initiative in the sense that water is not allocated pursuant to seasonal variability of water availability, but is instead licensed at the same rate for a period of up to 10 years (Skurray, 2015). This can create a problem where “insisting on last year’s consumption this year may reduce the availability of next year’s resource flows” (Skurray, 2015).

The danger of such a policy to a waterwet area like the East Kimberley may be less immediate, but accounting for rainfall variability can still be achieved in a way that attains certainty for agricultural users with large licences.

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by WSPs will be checked periodically to ensure their full use because the unused water could be put to use in the same or another ‘high beneficial use’ industry (Water and Rivers Commission, 2003). In this way the Policy aims to ensure continued productivity of the water entitlements. The combination of the above factors potentially restricts stakeholders like irrigation co-operatives from trading the unused licence entitlement, particularly as they have a high beneficial use licence that the Minister could transfer to another equally high beneficial use. However, it is arguable that reducing government involvement and permitting the market to operate is a more efficient outcome if the option to trade is available and the outcome is the same. Essentially, permitting trade between licence categories could have the effect of cutting out the ‘middle man’ (the Minister), while facilitating the same result of putting all licensed water to high beneficial use.

WCEP Policy The WCEP Policy is the most sympathetic to the argument of permitting trade between licence categories. It details under what circumstances efficiency measures can be engaged to circumvent recoupment procedures and activate trade of unused water entitlements. The plans created under the Policy are generally required for big users that also require an operating strategy. The Policy includes broad frameworks to guide efficiency improvements in industries such as mining, irrigated agriculture and WSPs or irrigation water providers (DOW, 2009). The key efficiency measures for WSPs include metering, leak detection and repair, system maintenance and reporting on causes of lost water (DOW, 2009).

Questions of existing efficiency are crucial to the application of this Policy.

Any large stakeholder, be it a mining entity, town water supplier, irrigation co-operative or power generator, will likely already be subject to WCEP plans by virtue of being subject to an operating strategy. Questions arise as to how much more efficient these stakeholders can become if – and this is a notable presumption – the plans are improving efficiency.

It is arguable that stakeholders may forego the opportunity to trade any water saved in the recent past through efficiency gains – a sub-optimal economic

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outcome. This is on the basis that their efficiency might have improved at a time when they were legally unable to trade between licence categories and there were no licensees of the same category willing or needing to trade water. The practical implications of this are to punish past efficiency improvements on the basis of policy prohibitions that are passive in law and to deny the prospect of a water market. The merits of such a policy in a region subject to continued growth and development are dubious at best. It seems particularly unpalatable if the result is the Minister recouping the unused water, conferring it to another high beneficial user, and incurring administrative red tape, possible legal action and restricting the operation of market forces.

SECTION 4: CONCLUSION The implementation of the water law framework in the East Kimberley is impacted by unnecessary policy prohibitions on trade, with support from passive restrictions contained in the RiWI Act. Although the region is ‘water-wet’, there are two clear reasons why trade between categories of licences should be permitted. The first is to permit the realisation of overarching policy commitments to facilitate efficient use and water trade in the state’s water law.

Achieving these outcomes is substantially hindered if policy requirements both unnecessarily outweigh legal provisions and sometimes reveal a level of discrepancy.

The second reason is to provide consistency between individual water policy objectives, so that stakeholders can be rewarded for efficiency improvements and the region can be developed with an active water trading market. The water market is currently neither administratively unrestricted nor particularly flexible in terms of trading water for purposes other than its original use. With minor adjustment of the legal framework, these shortcomings can be overcome to enable trade between the key stakeholders in the area. As the region grows, greater strain will be placed on its resources; addressing water market shortcomings now to permit trade between licence categories will better position the region for future development.

THE AUTHOR Dr Madeleine Hartley (email: madeleinehartley@ kingfisherlaw.com.au) is a solicitor at Kingfisher Law (www.kingfisherlaw.com.au), a boutique Sydney law firm with experience in state and national water law. The Author’s PhD thesis examined regulating groundwater use efficiency for sustainable development in Colorado (USA), the Namoi Catchment (NSW) and the Gnangara Mound (WA). The Author notes that the RiWI Act is in the process of being replaced with new legislation and the Water Resources Management Bill is currently being drafted.

REFERENCES Australian Co-operative Development Services Ltd (2015): Australian Co-operative Links, www.coop development.org.au/walinks.html [29 May 2015].

Department of Water (2013): Ord Surface Water Allocation Plan.

Department of Water (2010): Operational Policy 5.13: Water Entitlement Transactions for Western Australia.

Department of Water (2009): Operational Policy No. 1.02 – Policy on Water Conservation/ Efficiency Plans.

Department of Water (2007): Western Australia’s Implementation Plan for the National Water Initiative.

Hartley M (2014): Regulating for Groundwater-Use Efficiency: A Toolbox Approach Based on the Experiences of Three Disparate Jurisdictions.

Environmental and Planning Law Journal, 31, pp 109–112.

Hartley M (2013): Problematic Governance of Groundwater Use Efficiency on the Gnangara System, Perth. Australian Environment Review, 28, p 496.

Kwasniak A (2010): Water Scarcity and Aquatic Sustainability: Moving Beyond Policy Limitations. University of Denver Water Law Review, 13, p 332.

MacroPlanDimasi (2013): East Kimberley @ 25k: Shire of Wyndham East Kimberley, p 8.

Skurray J (2015): The Scope for Collective Action in a Large Groundwater Basin: An Institutional Analysis of Aquifer Governance in Western Australia. Ecological Economics, 114, pp 132.

Skurray J, Pandit R & Pannell D (2012): Institutional Impediments to Groundwater Trading: The Case of the Gnangara Groundwater System of Western Australia. Journal of Environmental Planning and Management, 56, p 11.

Waitt G, Lane R & Head L (2003): The Boundaries of Nature Tourism. Annals of Tourism Research, 30, pp 523, 526.

Water and Rivers Commission (2003): Statewide Policy No 11: Management of Unused Licensed Water Entitlements.

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QUANTIFYING WATER QUALITY CHARACTERISTICS OF STORMWATER Assessment of untreated stormwater for the Adelaide Airport and Barker Inlet stormwater-aquifer storage and recovery recycled water schemes P Reeve, P Monis, M Lau, K Reid, B van den Akker, A Humpage, B King, F Leusch, A Keegan

ABSTRACT

INTRODUCTION Stormwater is harvested for a range of uses including industrial and commercial activities, restricted/unrestricted municipal irrigation, landscape irrigation and dual reticulation. These applications have differing levels and types of human exposure and, therefore, characterisation of the stormwater quality is an important part of the risk assessment process.

Urban stormwater can contain pollutants or hazards such as heavy metals, hydrocarbons, organic chemicals and pathogens. Pathogens are of key concern because they have human health effects associated with single dose exposures.

The Australian Guidelines for Water Recycling – Phase 2 – Stormwater Harvesting and Reuse (2009) appendices 2 and 3 provide summary statistics on

METHODOLOGY Rain events Six discrete sampling events were undertaken at Adelaide Airport and Barker Inlet between May and December 2013, based on a rainfall trigger. The criterion for defining a rain event was >5 mm rainfall.

Physicochemical, nutrients and metal analysis Following collection, samples were analysed for nutrients, inorganic metals and other physicochemical parameters. Analyses were carried out by the Australian Water Quality Centre (Adelaide) and ALS Group Laboratories (Melbourne).

Microbiological analysis Stormwater samples were analysed for indicator bacteria, bacterial pathogens, enteric protozoa and adenovirus. Male specific coliphages were quantified by a plaque assay using a soft agar overlay technique as described by USEPA 2001. A single format assay was used to obtain protozoa oocyst/cyst counts and identify infectious oocysts as described by Swaffer et al.

(2014). Samples for adenovirus analysis were concentrated using ultra filtration cartridges and polyethylene glycol (PEG).

DNA was extracted using the QIAamp extraction kit according to manufacturer’s instructions (Qiagen, Germany) and enumerated by PCR (Heim et al., 2003).

All other samples were sent to the Australian Water Quality Centre for processing.

Chemical analysis Quantification of pesticides and herbicides in the stormwater samples were analysed by NATA-accredited laboratory Queensland Health Forensic and Scientific Services (Queensland, Australia). Quantification of BTEX, PAHs and phenolic compounds in the stormwater samples were analysed

by NATA-accredited laboratory ALS Group Laboratories.

Toxicity screening Stormwater samples were concentrated and extracted using solid phase extraction (SPE) as described

by Macova et al. (2011). Algal physiology (inhibition of photosynthesis using imaging pulse-amplitude modulated (IPAM)) and Ah-receptor (Ah-R) bioassays were conducted by the National Research Centre for Environmental Toxicology in Brisbane, Queensland).

The IPAM and Ah-receptor response assay was performed according to Tang et al. (2013) and Macova et al. (2010).

Estrogenicity and immunotoxicity bioassays were conducted by Griffith University (Brisbane, Queensland), as described by Leusch et al. (2014).

AUGUST 2015 WATER

STORMWATER MANAGEMENT

This project characterised untreated stormwater quality for the Adelaide Airport and Barker Inlet stormwateraquifer storage and recovery recycled water schemes. Stormwater quality was characterised in terms of physiochemical parameters, nutrients, metals and microbiological health parameters and results were compared to guideline values. Bioassays were also carried out to test for potential impacts on biota and any potential antagonistic or synergistic effects of potential chemicals. Results showed faecal indicator organisms were consistently present in the stormwater samples. Enteric protozoa Giardia and Cryptosporidium were also detected.

Low levels of herbicides were detected in some samples. The generation of pathogen and chemical data is necessary to improve our understanding of stormwater quality, process design, the development of contingency plans and risk management, refinement of monitoring programs and to build confidence with regulatory authorities.

stormwater quality. The first aim of this project was to build on the stormwater quality dataset and characterise the raw, untreated stormwater quality as it comes off the catchment prior to a holding basin or wetland where settling or assimilation of contaminants can occur. The second aim was to determine and relate stormwater quality to any potential biological effects using bioassays. Stormwater sampling was undertaken for the Adelaide Airport and Barker Inlet schemes, both of which incorporate treatment technologies to produce recycled water fit for dual reticulation. The Adelaide Airport stormwater scheme harvests water from the Brown Hill/Keswick Creek catchment, which is predominantly residential with some rural areas. Gross pollutant traps and silt traps are located along the catchment channels to assist in reducing contamination. Barker Inlet stormwater is harvested from the Barker Inlet wetlands, which are supplied by four drainage systems from an industrialresidential catchment. The information collected from both stormwater catchments will supplement scheme verification monitoring programs and assist in stormwater risk management.

74

Technical Papers RESULTS & DISCUSSION PHYSIOCHEMICAL AND NUTRIENTS

STORMWATER MANAGEMENT

Results of the physiochemical parameters and nutrient analyses from the six sampling events in 2013 are shown in Table 1. The results show the minimum and maximum detection range, mean value and standard deviation and, as a guide for water quality parameters, we include the Australian Drinking Water Guidelines (ADWG) values (NHMRC, 2011) and Environmental Protection Authority (EPA) aquatic freshwater guideline values (EPA, 2010). From these results it is apparent that there are limited guidelines available for a wide range of general physicochemical and nutrient parameters.

On average, Adelaide Airport recorded lower turbidity and suspended solids readings than Barker Inlet. The average recordings for both parameters at Barker Inlet were higher than the EPA guideline of 20 NTU and 20 mg/L respectively. In addition, the total organic carbon (TOC) concentrations at Adelaide Airport and Barker Inlet were high. The managed aquifer recharge guidelines describe low-quality source water as water that contains TOC values >10 mg/L (NRMMCEPHC-AHMC. 2009). Both locations had a mean value in the moderate quality range of 1–10 mg/L with values of 8.0 and 6.0 respectively. Elevated TOC concentrations can increase the potential of aquifer dissolution and, therefore, are a potential process risk.

Fertilisers and runoff from agricultural land are common ways in which nitrogen and phosphorus sources can enter waterways. The total nitrogen (TN) and total phosphorus (TP) concentrations are indicators of pollutants present in stormwater. Adelaide Airport had a TN concentration range of <0.1–2.4 mg/L, whereas Barker Inlet had more consistent detections at lower concentrations with a range from 0.3–1.2 mg/L (Table 1). These concentrations are low. The maximum TP detection at Adelaide Airport was 0.48 mg/L, slightly under the EPA guideline. This peak in TP did not coincide with maximum TN concentrations. The maximum TP detection at Barker Inlet was 0.35 mg/L. The variability in TN and TP concentrations may result from rainfall variability across events and seasonal changes that may impact horticultural practices.

METALS

Table 2 shows the range of 17 metals that were measured in total and/or soluble form. From the range of metals detected, three metals including lead, iron and zinc exceed the guideline levels. The median detection concentrations of total lead in the stormwater samples from both Adelaide Airport and Barker Inlet were above the EPA discharge water guideline value of 0.005 mg/L (Table 2). The average recording at Adelaide Airport was 0.006 mg/L with a maximum detection of 0.023 mg/L. Barker Inlet had a higher average of 0.009 mg/L with a maximum detection of 0.025 mg/L. In terms of iron and zinc,

the Adelaide Airport stormwater scheme has site-specific EPA harvesting guidelines that have been derived from groundwater quality data. Although a higher criterion has been allocated for these metals at Adelaide Airport, the values were exceeded (in one sampling event). In comparison, the values were continuously above the given guideline values at Barker Inlet. Increased iron levels (also manganese) present in harvested stormwater water may be problematic, depending on its end use, as it can affect the colour of the water, which could lead to staining of clothes.

MICROBIOLOGY

Faecal indicators E. coli, Enterococci and somatic bacteriophage were detected in stormwater samples from Adelaide Airport and Barker Inlet (Table 3). Male specific bacteriophage, Campylobacter spp. and Salmonella were also consistently detected in samples taken from both sites.

Cryptosporidium was detected in Adelaide Airport and Barker Inlet samples, with presumptive numbers ranging from 15–77 and 0–72 oocysts/10L respectively. Where infectious foci were detected, the infection was noted to be sub-lethal or atypical, with DNA sequence analysis of the infectious samples identifying C. bailey, C. meleagridis and Cryptosporidium species.

No human infectious Cryptosporidium (parvum or hominis) were detected in the samples, suggesting environmental sources of contamination rather than human sewage. This result was supported by direct genotyping of oocysts in stormwater samples, which detected animal-associated

Table 1. Physicochemical and nutrient analysis of stormwater samples from Adelaide Airport and Barker Inlet (n=6).

Adelaide Airport Parameter

Barker Inlet

Guidelines

Unit

n

Min

Max

Mean ± SD

n

Min

Max

Mean ± SD

ADWG

EPA

pH

6

7

7.5

7.3 ± 0.2

6

7.1

8.4

7.7 ± 0.5

6.5-8.5

6.5-9

Conductivity

µS/cm

6

72

470

217 ± 141

6

113

324

208 ± 82

TDS (by EC)

mg/L

6

39

260

120 ± 79

6

62

180

114 ± 45

Suspended solids

mg/L

6

2

26

10 ± 9

6

6

87

29 ± 29

Turbidity

NTU

6

3.9

21

9.3 ± 6.1

6

13

76

28 ± 24

Alkalinity

mg/L

6

25

115

59 ± 33

6

32

73

46 ± 15

Ammonia as N

mg/L

6

0.02

0.05

0.03 ± 0.01

6

0.04

0.73

0.23 ±.25

Nitrite + Nitrate as N

mg/L

6

0.03

0.26

0.13 ± 0.09

6

0.19

0.31

0.25 ±.01

TKN as N

mg/L

6

<0.1

2.2

6

<0.1

1.2

Total nitrogen

mg/L

6

<0.1

2.4

6

0.3

1.5

Total phosphorus

mg/L

6

<0.01

0.48

6

0.04

DOC

mg/L

6

2.4

19.9

7.0 ± 6.5

6

2

TOC

mg/L

6

2.5

22.6

8.0 ± 7.3

6

2.6

Physicochemical pH

600a 20 5

a

20

Nutrients 0.5a

0.7 ±.5

5

0.35

0.17 ±.1

0.5

8.9

4.4 ± 2.6

9.7

6.0 ± 2.7

ADWG health guidelines, a= ADWG aesthetic guidelines, EPA aquatic freshwater guidelines, Total Kjeldahl Nitrogen = TKN, Total Dissolved Solids = TDS, Dissolved Organic Carbon = DOC, Total Organic Carbon = TOC.

WATER AUGUST 2015

75

Technical Papers

Table 2. Metals analysis of stormwater samples from Adelaide Airport and Barker Inlet (n=6).

Adelaide Airport

Barker Inlet

Guidelines

Metals

LOR (mg/L)

Mean ± SD

Mean ± SD

ADWG

EPA

Aluminium(sol)

0.001

0.018 ± 0.009

0.025 ± 0.015

0.2a

0.1

0.05

Aluminium

0.001

0.289 ± 0.158

0.855 ± 0.665

Arsenic(sol)

0.0003

0.0015 ±0.0007

0.0008 ± 0.0001

Arsenic

0.0003

0.0015 ±0.0009

0.002 ± 0.002

0.01

Boron(sol)

0.02

0.05 ±0.07

0.08 ± 0.07

4

Cadmium

0.0001

0.0001

0.00003 ± 0.0001

0.002

Calcium

0.002

15.2 ± 8.8

12.3 ± 2.1

0.0001

0.001 ±0.0003

0.002 ± 0.001

0.05

Copper

0.0001

0.006 ±0.0027

0.0071 ± 0.0037

2, 1a

0.01, 0.037*

Iron(sol)

0.0005

0.1003 ± 0.1000

0.037 ± 0.008

Iron

0.0005

0.5205 ±0.346

0.8316 ± 0.6641

0.3a

1, 3.8*

Lead

0.0005

0.0064 ±0.0083

0.0091 ± 0.0083

0.01

0.005

0.05

4.87 ±3.21

2.61 ± 1.04

Manganese(sol)

0.0001

0.0013 ±0.0013

0.0011 ± 0.0005

Manganese

0.0001

0.0397 ±0.0818

0.0170 ± 0.0112

0.5, 0.1a

Mercury

0.00003

0.00001 ±0.00002

0.00001 ± 0.00002

0.001

0.0001

Nickel

0.0001

0.0008 ±0.0005

0.0021 ± 0.001

0.02

0.15

Magnesium

Potassium

0.05

2.52

2.61 ± 0.98

Sodium

0.1

18.7 ±13.6

23.7 ± 14.4

Sulphur Zinc

1.5

11.4 ±8.1

11.5 ± 5

0.003

0.088 ±0.037

0.106 ± 0.042

180a 0.05,0.14*

Table 3. Microbial analysis of stormwater samples from Adelaide Airport and Barker Inlet.

Adelaide Airport Unit

n

Mean

Barker Inlet

SD

n

Mean

SD

Faecal Indicators E. coli

cfu/100mL

6

10,997

15,114

6

17,017

17,422

Enterococci

cfu/100mL

6

25,313

26,951

6

28,433

16,916

Somatic bacteriophage

pfu/100mL

6

1,147

678

6

63,742

146,777

F-RNA bacteriophage

pfu/100mL

5

290

288

6

383

304

Bacterial Pathogens Campylobacter spp.

cfu/L

6

26

61

6

1

3

Salmonella spp.

detect/no detect

6

+

0

6

+

0

Cryptosporidium1

oocyst/10L

5

47

22

5

26

29

Cryptosporidium infectivity

foci

5

1

1

5

0

0

cyst/10L

5

102

152

5

24

32

0

6

<10

0

Enteric Protozoa

Giardia1

Viruses Adenovirus (PCR) 1

presumptive count, + detected

gene copies/L

6

<10

There was no detection of pesticides above the limit of reporting, including organochlorines, organophosphates and synthetic pyrethroids, in any of the stormwater samples from either site. However, trace levels of tris(chloropropoyl) phosphate isomers (maximum level detected - 0.4 µg/L) and herbicides atrazine (maximum level detected - 0.04 µg/L), diuron (maximum level detected - 0.15 µg/L), metolachor (maximum level detected - 0.07 µg/L) and simazine (0.09-0.43 µg/L) were detected, exceeding EPA guidelines for injection of stormwater into an aquifer; they require zero; below limit of detection (LOD) of any herbicide.

TOXICITY SCREENING

3a

ADWG health guidelines, aADWG aesthetic guidelines, EPA aquatic freshwater guidelines, * Adelaide Airport EPA- MAR site specific guideline, total metals are shown unless (sol) = soluble, LOR = Limit of reporting.

Parameter

HERBICIDES AND PESTICIDES

The results of the chemical analyses correlated with the toxicity screening assay results. The IPAM assay responds to specific chemicals such as herbicides (i.e., diuron, simazine, atrazine) and the results of this assay correlated to the herbicide data, which identified low levels of herbicides in stormwater samples across both locations. AhR is a generic assay that detects a range of chemicals including PAHs and dioxins. While it is not possible to relate the results of this particular assay to specific chemicals, the results suggest a quality similar to drinking water (Escher et al., 2014). These results corresponded to the chemical analysis, which showed concentrations that were below the level of detection. Low estrogenic activity was detected in half of the stormwater samples, from <0.01 to 0.05 ng/L 17β-estradiol equivalents. This is comparable to what has previously been reported for groundwater (Leusch et al., 2010), and clearly confirms minimal sewage contamination. The concentrations reported here are several orders of magnitude lower than the aquatic environment PNEC of 1 ng/L for

AUGUST 2015 WATER

STORMWATER MANAGEMENT

0.1

Chromium

isolates including C. ubiquitum and C. meleagridis. In addition to Cryptosporidium, Giardia was also detected at both sample locations.

Adelaide Airport had numbers ranging from 0–400 cysts/10L, whereas Barker Inlet had a range of 0–78 cysts/10L. Human infectious adenovirus was not detected in the stormwater samples.

76

Technical Papers 17β-estradiol (reviewed in SA EPA 2008), and are thus unlikely to pose a significant risk. The results for the immunotoxicity assays showed no activity across samples from both locations. These results further suggest there was little to no wastewater ingress into the stormwater at these sites during the sampled rainfall events.

STORMWATER MANAGEMENT

CONCLUSION Effective stormwater quality assessment requires identification of potential stormwater pollutants. This study characterised stormwater from two sites in Adelaide, South Australia, for possible pollutants which could impact on either human health and/or the environment.

The relatively low variability in bioassay results between the samples indicates that stormwater quality was relatively consistent across all sampling events. The results suggest low or no contamination from human sewage overflows into the stormwater and this is also reflected in the microbial results where no human infectious adenovirus or Cryptosporidium species were detected. The majority of pathogens detected were of animal rather than human origin, indicating contamination of the catchment from domestic or native animals.

The information collected will add value to existing monitoring and research efforts and assist in assigning alternative screening tools for stormwater assessment.

This paper was first presented at Ozwater’15 in Adelaide.

ACKNOWLEDGEMENT The Authors would like to thank Water Research Australia (WaterRA 3015-11) for its financial contributions to this project.

THE AUTHORS Dr Petra Reeve (email: Petra.Reeve@sawater. com.au) is a Wastewater Research Scientist at SA Water Corporation.

Dr Paul Monis (email: Paul.

Monis@sawater.com.au) is a Senior Scientist with the Source Water and Environment Research team at SA Water Corporation.

The research conducted in this group provides better information on the risks to water quality and supports risk management/risk mitigation.

Melody Lau (email: Melody.Lau@sawater.com. au) is a Source Water and Environment Research Scientist at SA Water Corporation.

WATER AUGUST 2015

Katherine Reid (email: Katherine.Reid@ sawater.com.au) is a Wastewater Treatment Performance Analyst at SA Water Corporation.

Dr Ben van den Akker (email: Ben.vandenAkker@ sawater.com.au) is a Senior Wastewater Research Scientist at SA Water Corporation. His principal research interests are in environmental and public health microbiology relating to wastewater treatment and reuse.

Dr Andrew Humpage (email: Andrew.Humpage@sawater. com.au) is a Senior Scientist specialising in chemical contaminates of water at SA Water Corporation.

Dr Brendon King (email: Brendon.King@sawater. com.au) is a Senior Research Microbiologist within the Source Water and Environment Research team at SA Water Corporation. He is actively involved in research and consultancies with an emphasis on investigating the protozoan parasite Cryptosporidium Associate Professor Frederic Leusch (email: f.leusch@griffith.edu.au) leads the Water Quality and Diagnostics Program at the Smart Water Research Centre at Griffith University. He is a member of the NHMRC Water Quality Advisory Committee, and Associate Editor for Chemosphere.

Dr Alexandra Keegan (email: Alex.Keegan@ sawater.com.au) is Manager of Wastewater Research at SA Water Corporation.

She is actively involved in research and consultancies for direct application to wastewater, recycled water and stormwater schemes for management of pathogens, nutrients and chemical constituents.

REFERENCES Escher BI, Allinson M, Altenburger R, Bain PA, Balaguer P, Busch W, Crago J, Denslow, ND, Dopp E, Hilscherova K, Humpage AR, Kumar A, Grimaldi M, Jayasinghe BS, Jarosova B, Jia A, Makarov S, Maruya KA, Medvedev A, Mehinto AC, Mendez JE, Poulsen A, Prochazka E, Richard J, Schifferli A, Schlenk D, Scholz S, Shiraishi F, Snyder S, Su G,

Tang JY, van der Burg B, van der Linden SC, Werner I, Westerheide SD, Wong CK, Yang M, Yeung BH, Zhang X & Leusch FD (2014): Benchmarking Organic Micropollutants in Wastewater, Recycled Water and Drinking Water With In Vitro Bioassays. Environmental Science & Technology, 48, 3, pp 1940–1956.

EPA (2010): Environmental Protection (Water Quality) Policy. Protected Environmental Values - Schedule 2. www.legislation.sa.gov. au/LZ/C/POL/Environment%20Protection%20 (Water%20Quality)%20Policy%202003.aspx Heim A, Ebnet C, Harste G & Pring-Akerblom P (2003): Rapid and Quantitative Detection of Human Adenovirus DNA by Real-Time PCR. Journal of Medical Virology, 70, pp 228–239.

Leusch F, Khan S, Laingam S, Prochazka E, Froscio S, Trinh T, Chapman H & Humpage A (2014): Assessment of the Application of Bioanalytical Tools as Surrogate Measure of Chemical Contaminants in Recycled Water.

Water Research, 49, pp 300–315.

NHMRC (2011): Australian Drinking Water Guidelines. ISBN 1864965118. www.nhmrc. gov.au/guidelines/publications/eh52.

NRMMC-EPHC-AHMC (2009): National Water Quality Management Strategy Australian Guidelines for Water Recycling: Managing Health and Environmental Risks (Phase 2) Managed Aquifer Recharge. www. environment.gov.au/system/files/resources/ d464c044-4c3b-48fa-ab8b-108d56e3ea20/ files/water-recycling-guidelines-mar-24.pdf NRMMC-EPHC-AHMC (2009): The Australian Guidelines for Water Recycling – Phase 2 – Stormwater Harvesting and Reuse. www. environment.gov.au/resource/national-waterquality-management-strategy-australianguidelines-water-recycling-managing-2 Macova M, Toze S, Hodgers L, Mueller J, Bartkow M & Escher B (2011): Bioanalytical Tools for the Evaluation of Organic Micropollulants During Sewage Treatment, Water Recycling and Drinking Water Generation. Water Research, 45, pp 4238–4247.

Swaffer B, Vial H, King B, Daly R, Frizenschaf J & Monis P (2014): Investigating Source Water Cryptosporidium Concentration, Species and Infectivity Rates During Rainfall-Runoff in a Multi-Use Catchment. Water Research, 67, pp 310–320.

Tang J, Aryal R, Deletic A, Gernjak W, Glenn E, McCarthy D & Escher B (2013): Toxicity Characterisation of Urban Stormwater with Bioanalytical Tools. Water Research, 47, pp 5594–5606.

USEPA (2001): Method 1601: Male Specific (F+) and Somatic Coliphage in Water by Two Step Enrichment Procedure. EPA number 821-R-01030, Washington, DC.

77

Technical Papers

WAIV TECHNOLOGY: AN ALTERNATIVE SOLUTION FOR BRINE MANAGEMENT Results of a full-scale demonstration trial conducted at a location near Roma in Queensland B Murray, D McMinn, J Gilron

ABSTRACT Wind Aided Intensified eVaporation (WAIV) Technology is an alternative solution for brine management, and has been developed for liquid waste minimisation to assist with enabling zero liquid disposal.

To evaluate WAIV Technology, a full-scale demonstration trial was conducted by a CSG operator at a location near Roma, Queensland. The trial successfully demonstrated that WAIV Technology can achieve enhanced evaporation compared to conventional evaporation ponds. Models to predict evporation have been developed as part of this evaluation. It is expected that these models can be applied to provide a reasonable estimate of evaporation performance using the WAIV Technology for alternative future locations.

INTRODUCTION

• Conventional evaporation ponds • Mechanical/thermal evaporation • Deep well injection The conventional approach is to install evaporation ponds to concentrate the brine for crystallisation and then to dispose of solid salt at a licensed repository facility. However, this approach may have a larger footprint, higher costs and a longer timeframe to achieve crystallisation. A range of

alternative evaporation technologies have been explored to accelerate the evaporation process.

WAIV technology as an alternative long-term, full-scale brine management technology for a range of industries.

A feasibility study identified Wind Aided Intensified eVaporation (WAIV) as a potential alternative technology.

It provides several advantages over other emerging enhanced evaporation technologies, such as utilising natural energy sources (solar and wind) to reduce operating costs and plant footprint.

BACKGROUND

WAIV technology has been proven to enhance evaporation 13-fold, based on a footprint-to-footprint comparison between a WAIV unit (pilot) and an open pan. Further data was required to evaluate evaporation performance and quantify potential benefits of using the WAIV technology, compared to conventional evaporation ponds.

A demonstration unit (one full-scale WAIV unit module) was constructed at a location near Roma, Queensland to gather performance data sufficient to evaluate the technology, and to develop a model to analyse and predict performance for larger-scale facilities. The results obtained from the demonstration trial have been compared against conventional evaporation pond performance and allow evaluation of

WAIV TECHNOLOGY

The Wind Aided Intensified eVaporation (WAIV) system uses wind energy to increase the evaporation rate of brine.

The WAIV system consists of a support structure that includes a number of fabric sheets (i.e. nets) suspended vertically from a support frame. The brine is slowly distributed across the sheets and flows down the sheets, concentrating as it falls, due to the evaporation effect of the wind passing across the surfaces. The concentrated brine is collected at the base of the system and recycled through the WAIV unit for further evaporation.

The WAIV unit design is optimised so that the sheets are positioned closely to get a good enhancement of evaporation capacity (through increased surface area) per footprint area without unnecessary blocking of the wind.

WAIV Technology is installed at full scale on plants in Australia, Israel and Mexico and is currently undergoing pilot testing and evaluation in other regions

AUGUST 2015 WATER

SALINE WASTE

The reverse osmosis (RO) process is one of the most common desalination technologies for the treatment of water extracted from coal seams during natural gas production. Concentrated brine as a waste product from RO needs to be appropriately managed to prevent any impacts on the environment in both the short and long term. There are a range of disposal options currently considered for the management of this brine waste product, which can include, but are not limited to:

Figure 1. WAIV Technology – Process Selection.

78

Technical Papers around the world. WAIV Technology has been developed by Lesico CleanTech in Israel and is made available in Australia under exclusive licence to IXOM. EVAPORATION

Evaporation performance is a function of the following meteorological parameters: • Temperature • Wind Direction • Wind Speed

Evaporation Driving Force

• Relative Humidity Many different equations have been developed to estimate evaporation performance.

The Harbeck Equation estimates evaporation using first principles.

Figure 2. Harbeck Equation for calculating evaporation.

Bar over the quantities implies an averaged value (over year, month or day).

Nomenclature from Harbeck Equation for evaporation from a pond:

The Harbeck Equation was developed in 1962 for estimation of evaporation from lakes in Western US and correlated data with pond surface temperature, air temperature and wind velocity. The equation holds in common with the Dalton Equation (19th century) and the Penman Equation (20th century) that the mass transfer component of evaporation is due to driving force of the wind.

Simulated evaporation data was also used, which was sourced from the SILO database. SILO is an enhanced climate database hosted by the Science Delivery Division of the Department of Science, Information Technology and Innovation (DSITI). SILO contains Australian climate data from 1889 in a number of ready-touse formats, suitable for research and climate applications.

SILO climate data can be readily sourced from “The Long Paddock” website (www.longpaddock.qld.gov.au) and the required historical data is simulated for any geographical coordinates.

Climate data can be simulated using the SILO database, and is

simulated for any set of geographical coordinates. The outputs from the SILO database can provide historical (simulated) pan evaporation data for the exact geographical coordinates nominated. Therefore, it avoids the need to install a local evaporation pan, and also avoids the need to wait for long periods of time to collect local climate data.

The benefit of using local pan evaporation is that local pan evaporation is a direct measurement, whereas the Harbeck Equation uses temperature, humidity, wind speed and so on, to estimate evaporation.

There are a number of other equations used for modelling evaporation. However, the Harbeck Equation was chosen to model the evaporation achieved using the WAIV Technology as it assumes evaporation is driven predominantly by mass transfer.

Evaporation performance using the WAIV Technology can be estimated using both the Harbeck Equation and empirical models.

Variables: E = daily evaporation rate (mm/d) from pond e = Vapour pressure (mbar)

SALINE WASTE

ea = vapour pressure in air, equal to pure water vapour pressure at ambient temperature multiplied by relative humidity e*w= vapour pressure of solution in the pond; for pure water this can be obtained from the Bolton equation which gives vapour pressure (in mbar) at temperature of water (in °C)

Figure 3. WAIV unit – full-scale unit dimensions.

u2 = wind speed at 2m above ground, (m/d) Ne = wind normalised mass transfer coefficient (mm/d/mbar)/(m/d) A = Area of pond, m2 Where:

(Bolton Equation for pure water vapour pressure, which holds well at climatic temperatures.)

WATER AUGUST 2015

Figure 4. WAIV unit – demonstration trial location.

79

Technical Papers PROCESS

Table 1. WAIV Demonstration Trial – typical feedwater composition (brine storage pond).

Parameter

Unit

Min

Max

Average

–

9.37

9.62

9.49

°C

18.8

30.9

25.1

Total Alkalinity (as CaCO3)

mg/L

2,160

3,110

2,593

Calcium (Ca)

mg/L

3

13

7

Magnesium (Mg)

mg/L

2

6

4

Sodium (Na)

mg/L

2,820

4,430

3,513

Potassium (K)

mg/L

50

89

65

Chloride (Cl)

mg/L

2,970

5,260

3,995

Sulfate (SO42-)

mg/L

85

524

275

Boron (B)

mg/L

0.75

1.02

0.87

Fluoride (F)

mg/L

7.9

9.7

8.6

Total Dissolved Solids (TDS)

mg/L

8,230

11,200

9,648

Electrical Conductivity (EC)

S/cm

13,000

18,500

15,300

pH Temperature

WAIV DEMONSTRATION

FEEDWATER QUALITY

TRIAL: SIZE & LOCATION

The feed used for the WAIV demonstration trial was sourced from a brine storage pond. The brine storage pond stored brine (i.e., RO reject) from an existing Reverse Osmosis plant located upstream of the WAIV demonstration unit.

Typical composition of the feed treated by the WAIV unit during the demonstration trial was as shown in Table 1.

Figure 3 shows the approximate dimensions of a full-scale WAIV unit.

The demonstration trial used 1 x full-scale WAIV module for the trial.

Figure 4 shows the setup and location of the WAIV demonstration trial conducted.

Evaporation 3m3/hr 15m3/hr

15m3/hr

Brine Tank

(190ML)

12m3/hr

Figure 5. WAIV unit operation – single pass*.

3m3/hr 15m3/hr

Brine Tank

2.

The brine is distributed evenly over the WAIV fabrics by a pipe manifold.

3.

The brine wets the WAIV fabrics and falls down and across the WAIV unit.

4.

Wind blows across the surface of the fabrics, evaporating water from the brine.

5.

Residual brine falls into the bunded area of the WAIV unit and into a sump.

6.

Residual brine in the sump is returned to the brine pond (single-pass) or to the holding tank (recirculation).

The demonstration WAIV unit was designed to operate at a flow rate of 15m3/ hr. The WAIV unit was operated in two basic modes during the trial, as follows: • Mode 1 – single-pass with relatively low TDS brine to determine evaporation performance in varying weather conditions; • Mode 2 – recycling to determine the impact of increasing brine concentration on the evaporation performance.

RESULTS EVAPORATION PERFORMANCE VS. WEATHER CONDITIONS

The WAIV unit evaporates water at different rates according to the prevailing weather conditions, which are constantly changing. Figure 7 (overleaf) illustrates the evaporation performance of the WAIV unit under weather conditions experienced during a specific 24-hour period. The data was collected in 15-minute intervals using a data logger, then plotted.

12m3/hr

Figure 6. WAIV unit operation – recycle* * Flows based on 20% evaporation through WAIV unit

• The bulk of evaporation occurs in the hours from 7am to 7pm; • The highest wind speeds occur between 7am and 7pm; • The relative humidity is high (i.e. >70%) during the hours from midnight to 7am;

WAIV

Brine Pond (190ML)

Brine is pumped from a holding tank to the top of the WAIV unit.

Figure 7 suggests the following:

Evaporation

3m3/hr

1.

• Temperature seems to have a relatively minor impact on the evaporation rate.

Analysing the results shown in Figure 7, evaporation due to the WAIV unit appears to be highly correlated to the local wind speed (i.e. driving force). As the wind speed increases, the relative

AUGUST 2015 WATER

SALINE WASTE

WAIV

Brine Pond

The basic operation of the WAIV demonstration trial unit was as shown in Figure 5 (single pass) or Figure 6 (recycling).

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Technical Papers

Figure 7. WAIV unit – evaporation performance over a 24-hour period (21/2/13). humidity drops, and as the wind speed drops the relative humidity rises. The chart also shows that the WAIV system can continue to evaporate without daylight if favourable conditions exist (i.e. the presence of some wind and relative humidity low enough to provide driving force). Therefore, enhanced evaporation using WAIV technology is achieved at any time when favourable weather conditions exist (i.e. provided wind speed in excess of 1–2 km/hr occurs).

EVAPORATION PERFORMANCE – ANNUAL

SALINE WASTE

The evaporation performance of the WAIV trial was evaluated over the entire period of the trial (August 2012 to January 2014).

To accurately evaluate WAIV system performance, only data consistent with the required design feed flow rate (i.e. actual results where flow was >12m3/hr) was used. The results for the WAIV demonstration trial that are representative of a full-scale WAIV system (i.e. 24 hr/day operation, >12m3/ hr flow rate) are displayed in Figure 8.

Table 2 shows that the evaporation performance results are similar for either single pass or recycle modes, despite the Table 2. WAIV unit trial – evaporation performance.

Evaporation Performance

Units

Single Pass

Recycle

Min

m3/day

4.4

5.6

Mean

m3/day

17.1

14.9

SD

m /day

5.4

5.2

Max

m3/day

32.0

28.8

3

Figure 8. WAIV unit – evaporation performance vs. brine electrical conductivity.

brine conductivity significantly increasing in the recycle mode.

evaporation performance is at least 10 times greater than that of the equivalent sized conventional evaporation pond;

Key observation from a review of the results suggest the following: • The WAIV unit achieved evaporation performance of 5–30m3/day, regardless of brine conductivity or operational mode.

The results suggest that daily variation in weather conditions have a more significant impact on evaporation performance than does brine conductivity.

Table 3 summarises the evaporation performance of the WAIV unit trial, on a monthly basis.

Table 3 shows the following: • In all instances the WAIV unit

• Annual daily average WAIV evaporation performance based on using all information listed in Table 3, was 11.9m3/day of water evaporated (i.e.

4,344m3/year). This is likely to be an underestimate of the true performance, as these results include some data from when the WAIV unit operated below the design feed flow rate (i.e. <15m3/hr).

• Annual daily average evaporation performance from a conventional evaporation pond of equivalent footprint area (160m2), was 0.5m3/day of water evaporated (i.e. 182m3/year).

Table 3. WAIV trial evaporation performance – monthly summary.

Average – Evaporation – Conv. Pond 160m2 (m3/day)

Average WAIV System – Average Flowrate (m3/hr)

Month

Mode

Average – Actual Evaporation – WAIV (m3/day)

Nov 12

Single Pass

21.68

0.78

12.2

Dec 12

Single Pass

14.20

0.57

12.9

Jan 13

Single Pass

17.71

0.59

13.7

Feb 13

Single Pass

12.32

0.57

14.7

Mar 13

Recycle

8.61

0.10

13.5

Apr 13

Recycle

9.09

0.47

9.2*

May 13

Recycle

2.90

0.13

5.4*

Jun 13

Recycle

2.03

0.19

13.5

Jul 13

Recycle

3.72

0.21

8.9*

Aug 13

Recycle

14.92

0.45

15.0

Sep 13

Recycle

14.67

0.71

15.0

Oct 13

Recycle

17.36

0.78

13.6

Nov 13

Recycle

15.13

0.30

14.0

Dec 13

Recycle

21.86

0.94

12.0

Recycle

23.5

1.09

12.0

EC – average

mS/cm

26.5

98.1

Jan 14

EC – max.

mS/cm

29.6

191.3

*Limited data available to provide monthly average WAIV daily evaporation

WATER AUGUST 2015

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Technical Papers

DR6

4m DR7

4m DR8

DR5

13m

3m

3m

WAIV Unit (20m x 8m)

2.6m

4.8m

DR1 DR2

4m DR3

4m DR4

Figure 9. Location of droplet drift collection pans.

These results indicate WAIV can evaporate 24 times more water than an evaporation pond on an equivalent footprint area (not including additional bunding for salt drift, discussed later).

WAIV PERFORMANCE – DROPLET DRIFT

Figure 11. WAIV unit – net tensioning

over a period of time to determine the quantity of salt collected at various distances away from the unit. Figure 9 shows locations of pans used for sampling and collecting the droplets.

Results from Figure 12 indicate the following:

Evaluation of droplet drift from the WAIV demonstration trial were as follows:

• The bunding required to ensure salt deposition (i.e. from droplet drift) is below 1 g/m2/day is limited to <10m from the edge of the WAIV system (after net tensioning);

• Comparison of droplet drift per day with the water evaporated per day indicated the proportion of losses due to droplet drift was less than 0.3%.

Therefore, more than 99% of all brine is kept inside the WAIV unit footprint area (including the surrounding 3m buffer zone).

• Using the WAIV net tensioning system, the droplet drift can be restricted to between 5–10m from the WAIV system (additional bundling required).

• Droplet drift was further reduced (i.e. 50–70%) after the WAIV unit nets (i.e. fabric sheets) were tensioned with shock cord on all sides (i.e. both up and downwind).

Alternatively, WAIV units can be located inside new and/or existing evaporation ponds, where droplet drift can return to the evaporation pond, so additional bunding is not required (see Figure 13).

Figures 10 and 11 show the WAIV demonstration unit after implementation of the WAIV net tensioning system.

Figure 12 compares salt deposition rates, relative to distance from the edge of the WAIV unit, both before and after WAIV net tensioning and for periods of different wind speeds.

Figure 12. Salt deposition vs. distance from WAIV unit – before and after WAIV net tensioning.

Bunding of 10m upwind and downwind is believed to be adequate to capture the droplet drift and prevent significant soil impact (i.e. salt deposit <1 g/m2/day).

WAIV TECHNOLOGY – EVAPORATION PERFORMANCE MODELS

One of the key objectives of the demonstration trial was to develop a model that can be used to estimate the evaporation possible using WAIV

Figure 13. WAIV system concept – WAIV units located inside conventional evaporation ponds.

AUGUST 2015 WATER

SALINE WASTE

Droplet drift from the WAIV unit has been raised as an issue for full-scale application, i.e. to ensure fall-out of brine droplets on the surrounding environment is minimised and managed appropriately.

The extent of droplet drift experienced during the WAIV demonstration trial was evaluated by collecting droplets on pans and measuring the contents

Figure 10. WAIV unit – net tensioning.

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Technical Papers

Table 4. Raw data inputs – evaporation performance models.

Harbeck Model (Theoretical)

SILO Data Model (empirical)

Temperature (°C)

Pan evaporation (mm/day)

Relative humidity (%)

Rainfall (mm/day)

Wind speed (m/sec) Wind direction (°) Barometric pressure (hPa) Rainfall (mm/day) Brine conductivity (mS/cm) technology for other potential locations that require brine management. Only performance data that was representative of a full-scale WAIV system (i.e. operation at approximately 12–15m3/hr) was used to develop the WAIV evaporation models.

Two methods were developed to model evaporation performance using the WAIV technology. The first method involved using the Harbeck Equation. The second method was developed using an empirical model and data available from the SILO Database. Table 4 summarises the raw data inputs required for each of the evaporation performance models.

SALINE WASTE

Figures 14 and Figure 15 show the actual evaporation performance experienced during the trial can be modelled with reasonable accuracy, using either the Harbeck Equation model (i.e. first-principles method) or the SILO data model (i.e. empirical method).

The key benefit of using the SILO data model is that it can be used where there is no historical data available from a local weather station. Based on the results achieved from modelling, it is expected that either evaporation model can be applied (i.e., subject to data availability), to provide a reasonable estimate for performance of WAIV technology for alternative future locations.

WAIV CRYSTALLISATION UNIT WAIV TECHNOLOGY – BRINE CRYSTALLISATION OPTIONS

A further alternative WAIV Technology system has been developed by Lesico CleanTech for crystallising salts on the surfaces of the WAIV fabrics and has

CONCLUSIONS

been demonstrated by Lesico

The WAIV technology trial successfully achieved the following outcomes:

CleanTech in Israel. This alternative WAIV technology system uses special fabrics designed for crystallising the salt on the fabric surface, instead of the conventional WAIV fabrics that are designed specifically for evaporating water.

This system has been designed for recovery of valuable salts (e.g., potassium chloride). Application of this alternative WAIV system can provide similar cost savings when compared to the construction of crystallisation ponds WAIV technology crystalliser options can significantly reduce the number of crystallisation ponds required for brine management. It is possible to set up a WAIV crystalliser system to achieve selective precipitation of various salts.

Figure 14. WAIV evaporation performance – Harbeck Equation model (theoretical) vs. actual.

WATER AUGUST 2015

Figure 16. WAIV crystallisation unit – precipitation of salt (sheets).

• WAIV technology can achieve enhanced evaporation compared to conventional evaporation ponds.

• Based on the analysis of the performance data (November 2012 to January 2014), the WAIV demonstration unit (i.e. one WAIV full scale module) is likely to achieve 11.9m3/day (i.e. 4,344m3/yr) of evaporation, based on the average performance over a 12-month period.

• Based on the same period, the annual daily average evaporation peformance from a conventional evaporation pond with an equivalent footprint area (160m2), was 0.5m3/day (i.e. 182m3/yr).

• These results indicate WAIV can evaporate 24 times more water than an evaporation pond on an equivalent

Figure 15. WAIV evaporation performance – model (empirical) vs. actual.

83

Technical Papers Recent work in Israel suggests that WAIV crystalliser options can be used for brine precipitation/salt crystallisation.

These options can significantly reduce the number of crystallisation ponds required for brine management. It is possible to set up a WAIV crystalliser system to achieve selective precipitation of various salts.

This paper was first presented at Ozwater’15 in Adelaide.

ACKNOWLEDGEMENTS

Figure 17. WAIV crystallisation unit – precipitation of salt. footprint area (not including additional bunding to capture droplet drift); • Models to predict the evaporation have been developed as part of this evaluation, and it is expected that they can be applied to provide a reasonable estimate for performance of WAIV technology for alternative future locations.

The Authors would like to acknowledge the assistance provided by key operations staff of both the CSG operator and IXOM; Lesico CleanTech; and data sourced from the SILO Database.

THE AUTHORS Brendan Murray (email: brendan.murray@ixom. com) is a Product Specialist with IXOM Operations Pty Ltd (formerly Orica Chemicals). He is a Chemical Engineer with over 13 years’ experience in the water sector, and is involved with commercialisation of the WAIV Technology.

David McMinn (email: david.mcminn@ixom. com) is a Senior Project Manager with IXOM Operations Pty Ltd. He is a Chemical Engineer and was the project manager for the WAIV demonstration project.

Jack Gilron is an Associate Professor and head of the Department of Desalination and Water Treatment at the Zuckerberg Institute for Water Research within the Blaustein Institutes for Desert Research at Ben Gurion University in Israel.

REFERENCES Gilron J, Folkman Y, Savliev R, Waisman M & Kedem Oren (2003): WAIV - Wind Aided Intensified Evaporation for Reduction of Desalination Brine Volume, Desalination and Water Treatment, 158, 205–214.

Katzir L, Volkmann Y, Daltrophe N, Korngold E, Mesalem R, Oren Y & Gilrone J (2009): WAIV – Wind Aided Intensified Evaporation for Brine Volume Reduction and Generating Mineral Byproducts, Desalination and Water Treatment, 000, 1–11.

3 no e 42 15 Volum Y 20 5 MA 8.9 rrP

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Technical Papers

TRENDS IN THE USE OF SURFACE IRRIGATION IN AUSTRALIAN IRRIGATED AGRICULTURE An investigation into the role surface irrigation will play in future Australian agriculture R Koech, R Smith, M Gillies

ABSTRACT Surface irrigation methods are simple, mostly gravity driven and, therefore, have low energy requirements. However, these systems are often seen as being inefficient both in labour and water usage.

As competition for scarce water resources and greater emphasis on environmental conservation gain ground, more focus has been directed towards surface systems.

On the one hand, some irrigators have converted to pressurised systems, which are seen to be more water efficient. This is reflected in the decline of 15% of the proportion of irrigated land in Australia under surface irrigation in the last two decades; however, the proportion of agricultural establishments using the system has remained relatively unchanged since 2002, except during the drought period when there was a reduction. In the US there has been a reduction in both the acreage under surface systems and the number of farmers using the system.

IRRIGATION

On the other hand, surface irrigation has experienced improvements ranging from upgrades of physical irrigation infrastructure and hardware to advanced management practices, including computer simulation and real-time optimisation and control. Conversion of irrigated land from surface to pressurised systems might continue into the future but probably at a decreasing rate. However, surface systems will nonetheless remain important. There is also the strong possibility that rising energy costs will curtail the adoption of pressurised systems.

Keywords: Furrow irrigation, bay irrigation, automated irrigation, irrigation statistics.

INTRODUCTION Surface irrigation refers to application methods in which water is conveyed over the field surface by gravity. In this case,

WATER AUGUST 2015

the soil surface acts both as a means of delivering water and the surface through which infiltration occurs. Surface irrigation is the main irrigation method in Australia and, in 2013–14, accounted for 59% of total irrigated land, mainly in the Murray-Darling Basin (ABS, 2015).

The system is particularly suited to the irrigation of pasture and broad-acre crops such as cotton, and those crops that benefit from being grown submerged in water (e.g. rice). In 2003–04 the method was used on 96% and 95% of farms producing rice and cotton respectively (ABS, 2008b). The most common configurations of surface irrigation in Australia are furrow and bay (or border check) irrigation, with lesser areas of basin and bankless channel systems.

Surface systems are simple to operate and have lower energy and initial capital requirements compared to pressurised systems; they are often associated with low water use efficiency and high labour requirements. For instance, application efficiencies (proportion of the volume of water added to the root zone to the total volume of water applied) for furrow-irrigated cotton under typical management practices in Queensland during the late 1990s were found to vary from 17% to 100%, with an average of 48% (Smith et al., 2005). The same study also demonstrated that there was a potential to lift the average efficiency (to about 75%) by increasing flow rates and reducing irrigation durations.

Further improvements in efficiency to the range of 85–95% were shown to be possible with the implementation of some form of real-time optimisation and control. Recent work in the cotton industry has shown that average efficiencies have increased (64.6%), but there is still significant room for improvement (Roth et al., 2013).

On the one hand, there is the need to continue and probably even expand the irrigation activities to cater for the increasing population, while on the other, there is the need to allocate more water for environmental conservation.

Central to achieving these diverse goals is the need to optimise the use of scarce water resources. Surface systems, as a result of their perceived low water use efficiency, have attracted a lot of attention. Opinion varies as to the future of surface systems, with one school of thought advocating improvements and another arguing for conversion to pressurised systems. This paper investigates the role surface irrigation will play in future Australian agriculture.

Trends in the proportion of the irrigated land under surface irrigation and the number of agricultural establishments using it are explored. The technological and management improvements that have been made to the system and their impacts are examined. An overview of emerging concepts related to the design and management of surface irrigation systems is presented. Finally, based on all the available information, an opinion is offered about the likely future for surface irrigation.

This study is primarily focused on the trends in Australia in the last two decades. However, the study also sought to corroborate Australian data with those of the United States (US), a comparable major irrigating economy. The Australian data were obtained from the Australian Bureau of Statistics (ABS) website, while the United States Department of Agriculture (USDA) website was the source of the US data. The study relied on the abundant published literature to document the improvements that have been made to surface systems and to highlight new concepts. To the authors’ best knowledge, no previous attempt has been made to

85

Technical Papers

To investigate trends, the data from individual surveys were plotted as time series. The percentage of irrigated land and the number of irrigators falling into each of the above irrigation methods were shown, together with the total irrigated land and number of farms respectively.

TRENDS IN THE USE OF SURFACE IRRIGATION IN THE LAST TWO DECADES IRRIGATION WATER USE

10000 9000 8000 7000 6000 5000

Period Figure 1. Total irrigation water use in Australia.

(Plotted from data obtained from: ABS 2004, ABS 2005, ABS 2006, ABS 2007, ABS 2008a, ABS 2009, ABS 2010, ABS 2011, ABS 2012, ABS 2013, ABS 2014 and ABS 2015)

3

80 70

2.5

60

2

50

40

1.5

30

1

20

0.5

10 0

0

Period Surface

Drip or trickle

Sprinkler

Others

Total area irrigated

Figure 2. Proportion of area of land in Australia irrigated using different application systems.

(Plotted from data obtained from: ABS 2004, ABS 2005, ABS 2006, ABS 2007, ABS 2008a, ABS 2009, ABS 2010, ABS 2011, ABS 2012, ABS 2013, ABS 2014 and ABS 2015)

AREA IRRIGATED

ABS data show that the total land under irrigation in Australia was approximately 2.5 million hectares in the period 2002–2006, before plummeting to about 1.7 million hectares in 2008–2009 (Figure 2). By 2012, the area had risen back to approximately 2.5 million hectares.

Clearly, the total area irrigated follows a similar trend to the irrigation water, and the reduction in area under irrigation was as a result of the severe drought.

Surface irrigation has remained the primary irrigation method in Australia, being used on 59% of total irrigated land in 2013–14 (Figure 2). This was

similar to the proportion in the period 2002–2005, but represents a reduction of approximately 15% when compared to 1990. Figure 2 shows the proportion of irrigated land under surface irrigation to be less than 51% during the severe drought of 2006–09. This is corroborated by cotton production statistics (discussed later in this paper), which show that there was a significant reduction in the area planted to cotton (Figure 5) during this period. As indicated earlier, cotton is predominantly grown using surface irrigation. Rice production experienced an even larger decline during this dry period (ABS, 2008b).

AUGUST 2015 WATER

IRRIGATION

Total irrigation water use in Australia between 2002 and 2014 is shown in Figure 1. It shows that total use between 2002 and 2006 was above 10,000 GL, but reduced to a low of just above 6,000 GL in the period between 2007–08 and 2010–11. In the period 2012–14 water use increased to a similar level as the early part of the available data (approximately 11,000 GL). Reduced use in the period 2006–2011 was a result of a severe drought across the MurrayDarling Basin that drastically reduced the availability of water for irrigation.

11000

Total area irrigated (million hectares)

The sections of the surveys relating to irrigation water management in the respective countries were particularly useful in the writing of this paper.

Each survey report detailed the type of irrigation method with respect to acreage of land and the number of farms. The drip or trickle and sprinkler systems were further subdivided into the various configurations of these systems. In this paper irrigation methods were classified broadly as follows: (i) surface; (ii) drip or trickle; (iii) sprinkler; and (iv) others. It is to be noted that some farms were irrigated using more than one irrigation method.

Irrigation water use (GL)

STUDY METHODS The primary data sources for this study were published agricultural surveys and farm and ranch irrigation surveys conducted by the ABS and the United States Department of Commerce (and later the USDA) respectively. The Australian surveys were undertaken in 2000–01, 2002–03, 2003–04, 2004–05, 2006–07, 2008–09 and 2009–2010, 2010– 11, 2011–12, 2012–13, and 2013–14. The 1979 US survey was conducted by the USDC (Bureau of Census) while the USDA (National Agricultural Statistics Service) was responsible for the 1998, 2003, 2008 and 2013 surveys.

12000

% of total irrigated land

analyse and interpret trends in surface irrigation in Australian irrigated agriculture, in spite of the availability of data. It is expected that this study will act as an important source of information for diverse players with an interest in irrigation.

86

70

23.0

60

22.0 21.0

50

20.0

40

19.0

30

18.0

20

17.0

10 1979

1984

1988

1994

1998

2003

2008

2013

15.0

Period Surface

Sprinkler

Drip or trickle

(Plotted from data obtained from: USDA 1990, Table 4; USDA 1999, Table 4; USDA 2006, Table 4.6.1; USDA 2009, Table 4; USDA 2014, Table 28)

IRRIGATION

WATER AUGUST 2015

sprinkler systems (Figure 3). This figure also shows that the total land area under irrigation has increased by about two million hectares from 1979 to 2013.

AGRICULTURAL ESTABLISHMENTS

The total number of farms in Australia that reported undertaking some form of irrigation decreased by approximately 17% during the period 2002–2014 (Figure 4). The fraction undertaking irrigation by surface systems during this period of time remained relatively stable, except during the previously mentioned

Australia experienced a significant decline in the land area under irrigation between 2006 and 2011 (Figure 2). There were also fewer agricultural establishments in 2013–14 compared to the period 2002–03 (Figure 4). According to ABS (2008a and 2010), the major reasons for this decline were: (i) widespread drought; (ii) reductions of area under irrigation as a result of reduced water allocations; and (iii) agricultural establishments that sold out their water rights and reduced their acreages, or stopped irrigation altogether.

The Australian irrigation statistics show that the proportion of land irrigated using surface systems has declined from over 70% in 1990 to just under 60% in 2014. The share of surface systems

60

% of total establishments

Statistics from the USDA website reveal that the proportion of land under surface irrigation in the US has declined by approximately 28% since 1979 (Figure 3). While the latest ABS statistics suggest that surface systems are still the main application method in Australia (Figure 2), in the US the system has been overtaken by sprinkler irrigation in terms of area of land irrigated (Figure 3). The drip/trickle methods (including subsurface drip) have also seen a slight uptake in the US in the last 30 years, but use is low compared to the surface and

In the US, the proportion of irrigators using surface systems was approximately 41% in 2003 and reduced to 32% in the 2013 survey (USDA, 2009; USDA, 2014).

The data also show that, as is the case in Australia, sprinkler irrigation is the method used by the majority of irrigators.

DISCUSSION ON TRENDS

Total area irrigated

Figure 3. Area of land in the US irrigated using different methods.

Figure 2 shows that during the drought period, which resulted in a reduction of the total land area under irrigation, the proportions of land irrigated using sprinkler and drip or trickle systems increased at the expense of surface systems. However, the proportions of land irrigated using sprinkler and drip/trickle methods before the drought (2004–05) and after the drought (2013–14) were similar.

This suggests that, although the methods accounted for a higher proportion of land irrigated during the drought (2006–09), there was no significant increase in the area under pressurised irrigation during this time; instead, much of the area that was surface irrigated was fallow during this drought. Surface irrigation systems are most likely to be used on those crops that are only planted in years with sufficient water supply, while pressurised irrigation, particularly drip irrigation, is more commonly used on those crops that are irrigated regardless of the availability or price of water.

drought period which includes the 2006–07 and 2008–09 data in Figure 4.

Sprinkler irrigation systems, the method preferred by the majority of agricultural establishments, also declined from a share of 58% to less than 50%. The data also show that the proportion of agricultural establishments using drip/ trickle systems has increased from 20% to 27% during the period 2002–2014.

50 45

50

No. of establishments (in thousands)

0

16.0

Total area irrigated (million hectares)

% of total area irrigated

Technical Papers

40 35

40

30 25

30

20

20

15 10

10

5 0

0

Period Surface

Drip or trickle

Sprinkler

Figure 4. Number of agricultural establishments irrigating in Australia.

(Plotted from data obtained from: ABS 2004, ABS 2005, ABS 2006, ABS 2007, ABS 2008a, ABS 2009, ABS 2010, ABS 2011, ABS 2012, ABS 2013, ABS 2014 and ABS 2015)

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Technical Papers HYDRAULIC MODELLING

700,000

Hectares (ha)

600,000 500,000 400,000 300,000 200,000 100,000 0

Period

Figure 5. Australian cotton production statistics. (Source: Cotton Australia website: cottonaustralia.com.au/cotton-library/statistics/) was markedly lower during the drought period (2006–11). On the other hand, the proportion of irrigators using surface systems has been relatively stable, except during the drought when there was a slight decrease. As already mentioned, the perceived disadvantages associated with surface systems are low water use efficiencies and high labour requirements.

Faced with the prospects of reduced water allocations, irrigators are being encouraged to switch to low pressurised systems, which are perceived to have higher water use efficiencies. Also labour requirements under these systems can be as little as 10% of the labour required in typical surface irrigation systems (Raine and Foley, 2002).

The data presented here show a strong correlation between the decline in the use of the surface system and the reduced irrigation water availability as a result of severe drought. This was particularly evident in the low acreages of annual crops such as cotton and rice, which are predominantly grown using surface systems. Figure 5 shows that, on average, between 2002 and 2010 there was less cotton grown than in the previous decade. However, the area under cotton production in 2010/11 was the highest in two decades. It is worth noting that during this period of time irrigators had access to sufficient water for irrigation, thanks to good rains (and floods).

1.

Water trading

2.

The Federal Government water buy-back program.

DEVELOPMENTS IN SURFACE IRRIGATION As a result of technological advancements and greater awareness of the need to ensure sustainable use of water resources, improvements have continued to be made to surface systems. These improvements have been in on-farm infrastructure and irrigation practices. The Federal and State Governments in Australia have provided funding for improvements in on-farm irrigation systems on condition that the water saved is surrendered to the environment (Plusquellec, 2009). The recent growth in computing technology and the internet has expanded the application of in-field sensors and the potential of simulation modelling in surface irrigation.

In the recent past, hydraulic simulation models have been applied in the optimisation of surface systems both at the design and management stages.

These models provide an opportunity to identify and evaluate more efficient practices at a lower cost and in a shorter time compared to field trials (Raine and Walker, 1998). Until recently, SIRMOD (Raine and Walker, 1998) was by far the most widely used irrigation design and simulation model in Australia and had been widely accepted as the standard tool for the evaluation and optimisation of surface irrigation (Gillies, 2008).

SIRMOD Version II formed the basis of the commercial evaluation service marketed under the name IrrimateTM (a suite of hardware and software tools developed by the National Centre for Engineering in Agriculture – NCEA).

The SISCO model (Gillies and Smith, 2015) developed recently at the NCEA has now superseded SIRMOD. The distinct difference between the SISCO model and the SIRMOD model is that the former is self-calibrating and has an in-built optimisation tool. This tool simulates all possible combinations of up to two management variables (e.g. inflow rate and cut off time) and assists the user in identifying the optimal combination of these variables.

SYSTEM AUTOMATION

Most of the infrastructural changes that have been developed and implemented in surface irrigation application systems in the recent past appear to have been directed towards moving the traditionally

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Other factors, the effects of which are not evident in the ABS data, but which will continue to affect water usage are:

Trading, particularly in the Murray River Basin, has seen water moving from surface irrigated pasture in the GMID (Goulburn-Murray Irrigation District) to new sprinkler irrigated horticultural developments along the lower reaches of the river (Thompson, 2015). The Government’s buy-back initiative has seen 1014 GL (average annual yield) removed from mainly surface irrigated areas and transferred to the environmental regulator as of 30 April 2015 under the ‘Restoring the Balance in the Murray-Darling Basin’ program (Australian Government – Department of the Environment 2015). It was estimated that to return the river system within the Murray-Darling Basin to health, a recovery of 2750 GL of surface water is required (Commonwealth of Australia 2014).

Hydraulic modelling in surface systems is the process of mathematically describing the hydraulic characteristics of water as it flows from one end of the field to the other. In surface irrigation, water infiltrates into the soil profile as it flows along the surface. Due to the nature of the soil infiltration characteristic, the flow is both spatially varied and unsteady (Walker and Skogerboe, 1987). Water flow within the field is hydraulically similar to unsteady open channel flow and thus can be described by the Saint Venant equations, which are based on the principles of conservation of mass and momentum. Models that have been used for the solution of these equations fall into one of the following four major categories: complete hydrodynamic models; zero inertia models; kinematic wave models; and volume balance models.

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Technical Papers outlets and pump control units where required; • A range of different in-field sensors including soil capacitance probes, water level sensors, flowmeters; • Wireless radio telemetry for communication among the different system components; • The use of batteries and/or solar power where no power is available in the remote devices.

Figure 6. Automated BayDriveTM, which is part of the FarmConnect® System.

(Source: Rubicon Water publicity brochure) manually-operated system to automatic control modes. The majority of modern control systems incorporate electronic and computer systems.

The developments that have occurred in the automation of surface systems have been biased towards bay and basin application methods. These systems are generally suited to automation because of simpler distribution of water over the soil surface (Humpherys, 1971). Initial attempts to automate these systems were focused on controlling the gates that supply water to the field. The use of sensors to sense the arrival of water at a particular point along the length of the bay or basin is a feature of most attempts at automation.

This is important in the management of the time to cut off flow into the bay or basin.

IRRIGATION

The communication between various components (for example, sensors and

(a) Manually operated Figure 7. PTB used in furrow irrigation.

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automatic gates) of modern automatic surface systems has been made possible by the use of wireless telemetry systems.

These systems allow measurements taken from a remote location to be conveyed to a central location via wireless means, such as radio, satellite and internet communication.

There is a range of different options in terms of commercially available systems for bay irrigation in Australia. Some notable examples are Aquator (GM Poly, 2013), FarmConnectTM (Rubicon Water, 2014), WiSA (WISA, 2015), SamC – Gate Keeper (PadMan Stops, 2015) and the variants of the Observant systems (Observant, 2015).

The basic features of these systems include: • A central control system located on a remote server, farm PC or one of the radio nodes; • Actuated bay gates or pipe and riser

(b) Automated

With most of these systems, an irrigator is able to set up a program to automatically switch on a pump, open and close bay gates, acquire soil moisture data and automatically switch off the inflow. Irrigation can be monitored and controlled via the internet. Most of these systems also have the capability to graphically display the farm being irrigated by use of satellite mapping and GPS positioning.

Developments in furrow irrigation have largely been handicapped by the challenge and potential cost of ensuring uniform distribution of water into individual furrows (Humpherys, 1971).

The automation of overbank siphons, the most popular means in Australia of transferring water from the head ditch into the furrows, has so far proved technically difficult. Pipes through the bank (PTB), another means of transferring water from the head ditch to a group of furrows, has largely remained manually controlled. There are, however, prospects of automating the opening and closing of the flap that controls the flow of water, as recently demonstrated at a furrow automation trial site in the Gwydir Valley (Koech et al., 2010).

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Technical Papers Previous efforts at automation of furrow irrigation published in the technical literature appear to have concentrated on the use of rigid gated pipe and include surge flow (Walker, 1989) and so-called cablegation (Kemper et al., 1987). However, none of these designs has been widely accepted because of cost and complexities.

In Australia, manually operated gated layflat systems are commonly used in the sugar industry. Recent work by Smith et al. (2015a) in the cotton industry has demonstrated prototype systems for the automation of furrow irrigation using: (i) large diameter layflat gated pipe; and (ii) small diameter pipes through the channel bank (Figure 8).

FEEDBACK AND REAL-TIME CONTROL

In the past two decades or so, a number of systems aimed at significantly improving the performance of surface system through some form of real-time control have been conceptualised. Most of these systems have been proposed as strategies for reducing the labour requirement and to improve the water use efficiency of the surface system.

The concept of feedback control in surface systems was conceived more than two decades ago. The concept, as implied by Niblack and Sanchez

(2008), means management decisions (e.g. time to cut-off of the inflow) are made based on signals received from sensors placed along the basin and triggered by the advancing water.

Niblack and Sanchez (2008) described a feedback system that is controlled by a predetermined cut-off time.

Clemmens (1992) defined feedback control as a system of control that utilises the measurements (including estimation of the infiltration characteristics of the soil) taken during the same irrigation event. Such a system has been termed 'real-time control’ by other authors (e.g. Khatri and Smith, 2006).

A feedback system utilising a vision system to monitor the advance of water is described by Lam et al.

(2007). This is particularly convenient as it can be placed outside the paddock, thereby allowing the unimpeded use of machinery. Adaptive control in surface systems generally refers to the continuous and automatic variation of the control strategy in response to the changing parameters of the system.

Such a system was specifically designed to counter the effects of the soil infiltration characteristics, which change both temporally and spatially.

A furrow irrigation system utilising an adaptive control algorithm was

developed by Hibbs et al. (1992). In this system the infiltration characteristics were analysed by a microcomputer and the inflow adjusted accordingly by an automatic valve. The system demonstrated higher application efficiencies than the conventional systems (Hibbs et al., 1992). There is, however, no evidence indicating widespread adoption of these concepts.

Research aimed at developing, proving and demonstrating an automated realtime optimisation and control system for furrow irrigation commenced in 2009 at the National Centre for Engineering in Agriculture (NCEA) based at the University of Southern Queensland.

To achieve the objective of the project, it was necessary to integrate a hydraulic simulation model with automation hardware. The system consists of five main components: water delivery system; an inflow measurement system; a water sensor to monitor advance of water along the furrow; a computer and a radio telemetry system to facilitate communication among the system components. The design (Koech et al., 2014a) involves the following: • Determination of the model infiltration curve from extensive evaluations; • Measurement of inflow to each furrow (or group of furrows); • Estimation of the infiltration characteristics of the trial furrow by scaling from the parameters of the model curve; • Simulation and optimisation (to a user-specified objective function) to determine the preferred time to cut-off of the inflow.

Field trials to test the system were undertaken on two commercial furrowirrigated cotton properties in St George and Dalby (both in Queensland) over two consecutive irrigation seasons (2010/11 and 2011/12). The results are presented in Koech et al. (2014b) and show that the system performed robustly in the field and demonstrated potential for water and labour savings.

IMPACTS OF IMPROVEMENTS IN SURFACE SYSTEMS

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Figure 8. Automated furrow irrigation with a Rubicon BayDrive All-in-One in the open position, viewed from upstream with the small diameter PTBs through the channel bank on the left.

Labour saving A survey on the perceptions of the irrigators found that 59% of those polled considered labour saving as the greatest benefit of farm automation (Maskey et al., 2001).

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Table 1. Benefits of simulation modelling in surface systems.

Location

Application system

Simulation tool

Strategy used

Benefits

Raine and Shannon, 1996

Burdekin River Delta

Furrow

SIRMOD

Decrease furrow length from 600 to 300m

Decrease of volume applied from 1.78 to 1.03 ML/ha/irrigation

Langat and Raine, 2006

Bura Irrigation Scheme, Kenya

Furrow

SIRMOD

Increased flow rate and optimised cut off time

Increased AE from 79.4 to 87.5%.

Raine et al., 2005

Queensland, New South Wales

Furrow

SIRMOD

Optimised siphon flow rates and time to cut off

Water saving of 0.15 ML/ha/ irrigation

Smith et al., 2005

Southern Queensland

Furrow

SIRMOD

Increased flow rates, reduced inflow times

AE increased from average of 48% to 85-95%.

Smith et al., 2009

Goulburn Murray Irrigation District (GMID)

Border

SIRMOD/ SISCO

Shorter irrigation times and higher flow rates

Gain in AE of 19%

Gillies et al., 2010

GMID

Border

SIRMOD/ SISCO

Doubling flow rate (from 0.132 to 0.268 ML/day/m).

Water savings of 0.256 ML/ha/ irrigation (19% increase in AE).

Roth et al., 2014

Australian Cotton Industry

Furrow

SISCO

Applying recommended flow and optimised cut-off

0.155 ML/ha per irrigation accounting for tail water recycling

Smith et al., 2015b

GMID

Automated Border

SISCO

Source

Water saving and improved performance Lavis et al. (2007) demonstrated water savings of between 5% and 9% in the Shepparton Irrigation Region, while initial results from a bay irrigation project using an intelligent irrigation controller and wireless sensor network at Dookie, northern Victoria, suggested that an average water saving of 38% could be realised (Dassanayake et al., 2009). More recently Smith et al. (2015b) showed automated bay irrigated dairy farms in northern Victoria were achieving application efficiencies in excess of 90% under usual farmer management.

IRRIGATION

The introduction of a commercial IrrimateTM evaluation service in 2001 heralded a new era for the cotton industry in Australia, whereby irrigators were presented with the opportunity to first evaluate the performance of their systems and then initiate improvements.

Assessments showed that most clients were able to save an average of 0.15 ML/ ha/irrigation after undertaking design and management changes (Raine and Montagu, 2006).

There is abundant evidence showing that the IrrimateTM commercial service has resulted in significant increase in water use efficiencies. For instance, the BDA Group (2007) estimated that the cotton industry has saved 400GL

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over a 16-year period, corresponding to an increase in water use efficiency of 10%. Application efficiency (AE) of individual irrigation events has also improved considerably from the low of 48% (average) reported earlier in this paper. In an evaluation of 47 furrow irrigation events in the Gwydir and Namoi Valleys, Montgomery and Wigginton (2006) found that almost half the events had an AE of over 90%, with only 35% of the events recording an AE of less than 80%. They also reported average water savings of 0.18 ML/ha for each irrigation event that was optimised for water saving. More published data on water savings and strategies used are summarised in Table 1.

THE FUTURE OF SURFACE SYSTEMS The data presented from irrigation surveys conducted in Australia (Figure 2) and the US (Figures 3 and 4) indicate a reduction in the proportion of land irrigated using surface irrigation (and in the proportion of farmers in the case of the US) using surface systems. The reduction in Australia is slow, apart from the temporary decrease and rebound that were observed during the decade-long severe drought that led to reduced water allocations for irrigation.

Nonetheless, from the data presented

Efficiencies up to 95% demonstrated in this paper, it is likely that more land currently under surface systems will be converted to the various forms of pressurised systems. There is no doubt, however, that in areas of insecure water supplies (e.g. Australia), or developing countries where the majority of farmers lack the necessary infrastructure or financial resources to modernise (Plusquellec, 2009) or convert to pressurised systems, surface irrigation will continue to dominate.

Surface irrigation in Australia is expected to remain important because of the following factors: (i) some strategic crops such as rice prefer ponded conditions; (ii) low initial capital requirement; (iii) low energy requirements; (iv) use of largely unskilled labour and minimum maintenance costs; (v) the cost of conversion to pressurised systems cannot always be justified, as shown by a study of the dairy industry in the Lower MurrayDarling Basin (Doyle et al. 2009); (vi) many pressurised systems need to be utilised every season, due either to the high capital cost or to prevent damage to the system (e.g. subsurface drip) and, hence, are not suited to the highly variable water availability in Australia; and (vii) there is a real possibility that ever-rising energy costs may limit the use of pressurised systems.

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Table 2. Illustration of energy use for furrow irrigation of a hypothetical grain crop from a surface water source. (Source: Khatri and Smith, 2011) Water applied (ML/ha)

Water savings (ML/ha)

Energy use (MJ/ha)

Current surface irrigation (AE 55%)

7.3

9700

Real-time optimised surface irrigation (AE 85%)

4.7

2.6

9700

0

Centre-pivot irrigation (AE 90%)

4.4

2.9

17000

7300

Drip irrigation (AE 95%)

4.2

3.1

16000

6300

System

A study by Jackson et al. (2010) proposed the promotion of surface and pressurised systems in surface and groundwater-supplied areas respectively.

They found that in the surface-water supplied region surveyed, conversion from surface to pressurised systems resulted in a reduction of water application of 10–66%; however, energy consumption increases of up to 163% were recorded. On the other hand, they found that conversion from surface to pressurised systems in groundwatersupplied areas resulted in a reduction in energy consumption of 12–44% due to the reduced volume of water pumped.

However, this study did not consider the potential water and energy savings (as a result of reduced pumping) of real-time optimised surface systems.

Khatri and Smith (2011) illustrated that, with real-time optimisation of surface irrigation, it is possible to achieve a reduction in water application rates without a corresponding increase in energy consumption (Table 2). They showed that, although marginally higher water savings can be achieved by conversion to centre-pivot and drip irrigation, the associated increase in energy consumption could be significant.

be the equipment cost (Maskey et al., 2001). A surface system as efficient as the pressurised systems will most likely be more appealing as a result of its lower cost. The use of intelligent controllers in surface systems is also expected to increase in the future.

CONCLUSIONS The proportion of irrigated land under surface systems in Australia has reduced by about 15% in the last two decades. This has been offset by uptake in sprinkler, drip/ trickle and other irrigation systems. The proportion of agricultural establishments using surface irrigation remained relatively stable during the period 2002–2014; however, it reduced during the period in which Australia experienced a severe drought. The decade-long drought caused a reduction in the water available for irrigation. In the US, a decline of 28% has been recorded in the proportion of land under surface systems in approximately three decades. Surface irrigation has now lost its dominance (to sprinkler methods) in terms of acreage under irrigation.

Low water use efficiency and high labour requirements appear to be the main factors leading to the decline of the surface systems.

Improvements to surface irrigation in the form of on-farm irrigation infrastructure and hardware, as well as changes to irrigation management practices, have been made in recent years. These improvements have been mainly biased towards the bay/basin systems. Computer simulation modelling has been used in improved design and management decision-making in surface systems.

The improvements made to the surface systems have led to improvements in water use efficiency, leading to water savings and reduction of labour requirement.

There is a wide variety of new approaches conceptualised and ongoing research in surface systems that have the potential to shape the future direction of the system.

THE AUTHORS Dr Richard Koech (email: rkoech@une.edu. au) is Program Leader, International Development and Training (Agriculture Water Management), School of Environmental and Rural Science, University of New England.

Prof Rod Smith is Professor of Irrigation Engineering in the National Centre for Engineering in Agriculture at the University of Southern Queensland.

Dr Malcolm Gillies (email: gilliesm@usq.edu.au) is a Senior Research Fellow of Hydraulic Engineering and Irrigation in the National Centre for Engineering in Agriculture at the University of Southern Queensland, Toowoomba.

REFERENCES ABS (2004, 2005, 2006, 2008a, 2010, 2011, 2012, 2013, 2014, 2015): Water Use on Australian Farms. Australian Bureau of Statistics, Cat. No. 4618.0, Canberra.

ABS (2008b): 2008 Year Book Australia, Number 90, Cat. No. 1301.0, Australian Bureau of Statistics, Canberra, Australia.

Australian Government – Department of the Environment (2015): Progress of Water Recovery Under the Restoring the Balance in the Murray-Darling Basin Program. Available online at: www.environment.gov.au/water/ rural-water/restoring-balance-murray-darlingbasin/progress-water-recovery [Accessed 23/06/2015].

BDA Group (2007): Cost Benefit Analyses of Research Funded by the CRD. Report to Cotton Research and Development Corporation, BDA Group, Manuka, ACT, Australia.

Clemmens AJ (1992): Feedback Control of Basin Irrigation System. Journal of Irrigation and Drainage Engineering, 118, 3, pp 481–496.

Commonwealth of Australia (2014): Water Recovery Strategy for the Murray-Darling Basin. Available online at: www.environment. gov.au/system/files/resources/4ccb1c76655b-4380-8e94-419185d5c777/files/waterrecovery-strategy-mdb2.pdf [Accessed 23/06/2015].

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Hence, it is possible that concerns about escalating energy costs and the associated negative environmental impacts (mainly greenhouse gas emissions) of energy sources may slow down the conversion to pressurised systems. There is also no doubt that some of the proposed new approaches, particularly automation and real-time optimisation and control, will lead to gradual improvement in the water use efficiencies and lower labour requirements. The various Australian Government programs of on-farm incentives will remove the major barrier to automation that has been shown to

Increase in energy use (MJ/ha)

The conversion of surface-irrigated land in Australia over to some form of pressurised system is expected to continue, but at a much slower rate.

However, it is improbable that surface irrigation will cease to be important in the near future. Apart from the low capital cost of the system, it is also likely that increases in the cost of energy will curtail the future expansion of pressurised systems.

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Technical Papers Dassanayake D, Dassanayake K, Malano H, Dunn GM, Douglas P & Langford L (2009): Water Saving Through Smarter Irrigation in Australian Dairy Farming: Use of Intelligent Irrigation Controller and Wireless Sensor Network.

18th World IMACS/MODSIM Congress, Cairns, Australia, 13–17 July 2009.

Doyle P, Gibb I & Ho C (2009): Review of Relevant Information on Potential Productivity Gains from On-Farm Irrigation Technology Australia by Murray-Darling Basin Inquiry.

Gillies MH (2008): Managing the Effect of Infiltration Variability on the Performance of Surface Irrigation. PhD Thesis, University of Southern Queensland, Toowoomba.

Gillies MH, Smith RJ, Williamson B & Shanahan M (2010): Improving Performance of Bay Irrigation Through Higher Flow Rates.

Australian Irrigation Conference and Exhibition, Sydney, 8–10 June 2010.

Gillies MH & Smith RJ (2015): SISCO: Surface Irrigation Simulation, Calibration and Optimisation. Irrigation Science, DOI 10.1007/s00271-015-0470-8.

GM Poly (2013): Aquator. Available online at: gmpoly.com.au/product_range/aquator [Accessed 9/7/2014].

Hibbs RA, James LG & Cavalieri RP (1992): A Furrow Irrigation Automation System Utilizing Adaptive Control. Transactions of ASAE. 35, 3, pp 1063–1067.

Humpherys AS (1971): Automation of Furrow Irrigation Systems. Trans. of ASABE, 14, 3, pp 460–470.

Jackson T, Khan S & Hafeez M (2010): A Comparative Analysis of Water Application and Energy Consumption at the Irrigated Field Level. Agricultural Water Management, 97, 2010, pp 1477–1485.

Kemper WD, Trout TJ & Kincaid DC (1987): Cablegation: Automated Supply for Surface Irrigation. Advances in Irrigation, D Hillel (Ed), Academic Press Inc., London, pp 1–66.

IRRIGATION

Khatri KL & Smith RJ (2006): Real-time Prediction of Soil Infiltration Characteristics for the Management of Furrow Irrigation. Irrigation Science, 25, 1, pp 33–43.

Optimisation System for Furrow Irrigation.

Agricultural Water Management, 142, pp 77–87.

National Conference, Irrigation Association of Australia, 19–21 May, Brisbane. pp 117–123.

Lam YS, Wallender DC & Upadhyaya SK (2007): Machine Vision Monitoring for Control of Water Advance in Furrow Irrigation. Trans. of the ASABE, 50, 2, pp 1162–1170.

Roth G, Harris G, Gillies M, Montgomery J & Wigginton D (2013): Water-Use Efficiency and Productivity Trends in Australian Irrigated Cotton: A Review. Crop and Pasture Science, 64, 11–12, pp 1033–1048.

Langat PK & Raine SR (2006): Using Simulation Modelling to Improve the Design and Management of Furrow Irrigation in SmallHolder Plots. Southern and Eastern African Rainwater Network, Mombasa, Kenya.

Rubicon Water (2014): FarmConnect Software.

Available online at: www.rubiconwater. com/catalogue/farmconnect-software-usa [Accessed 10/7/2014].

Lavis A, Maskey R & Lawler D (2007): Quantification of Farm Water Savings with Automation. Department of Primary Industries, Victoria.

Smith RJ, Gillies MH, Shanahan M, Campbell B & Williamson B (2009): Evaluating the Performance of Bay Irrigation in the GMID. Irrigation and Drainage Conference, Swan Hill, Victoria, Australia, 18–21 October 2009.

Maskey R, Roberts G & Graetz B (2001): Farmers’ Attitudes to the Benefits and Barriers of Adopting Automation for Surface Irrigation on Dairy Farms in Australia. Irrigation and Drainage Systems, 15, pp 39–51.

Montgomery J & Wigginton D (2008): Evaluating Furrow Irrigation Performance: Results from the 2006-07 Season. Surface Irrigation Cotton CRC Team Bulletin.

Niblack M & Sanchez CA (2008): Automation of Surface Irrigation by Cut-Off Time or Cut-off Distance Control. Trans. of the ASABE, 24, 5, pp 611–614.

Observant (2015): One Farm, One Solution.

Available online at: www.observant.net/ [Accessed 23/06/2015].

PadMan Stops (2015): Innovative Irrigation Solutions. Available online at: www. padmanstops.com.au/?product=samc-gatekeeper [Accessed 23/06/2015].

Plusquellec H (2009): Modernization of LargeScale Irrigation Systems: Is It An Achievable Objective or a Lost Cause? Irrigation and Drainage, 58, pp 104–120.

Raine SR, Purcell J & Schmidt E (2005): Improving Whole Farm and Infield Irrigation Efficiencies Using IRRIMATETM tools. Irrigation Association Australia, Townsville, Australia.

Smith RJ, Raine SR & Minkovich J (2005): Irrigation Application Efficiency and Deep Drainage Potential Under Surface Irrigated Cotton. Agricultural Water Management, 71, 2, pp 117–130.

Smith RJ, Uddin MJ & Gillies MH (2015a): Commercial Prototype Smart Automation System for Furrow Irrigation. Final report on project NEC1302 to Cotton Research & Development Corporation, National Centre for Engineering in Agriculture, USQ, Toowoomba.

Smith RJ, Uddin MJ & Gillies MH (2015b): Evaluation of the Performance of Automated Bay Irrigation. National Centre for Engineering in Agriculture Publication 1005612/1, USQ, Toowoomba.

Thompson C (2015): Goulburn Murray Irrigation District – A Changing Irrigation Landscape, Where Are We Heading? IAL 2015 Regional Conference, Penrith, 26–28 May. USDA (1990): Farm and Ranch Irrigation Survey (1988). Vol. 3, Special Studies Part 1, 1987 Census of Agriculture, AC87-RS-1-2.

USDA (1999): Farm and Ranch Irrigation Survey (1998). Vol. 3, Special Studies Part 1, 1997 Census of Agriculture, AC97-SP-1.

USDA (2006): Agricultural Resources and Environmental Indicators 2006 Edition.

Economic Information Bulletin No. 16.

Khatri KL & Smith RJ (2011): Surface Irrigation for Energy and Water Use Efficiency, Irrigation Australia Conference and Exhibition, Launceston, Tasmania, 22–25 August.

Raine SR & Shannon EL (1996): Improving the Efficiency and Profitability of Furrow Irrigation for Sugarcane Production. In: Sugarcane: Research Towards Efficient and Sustainable Production, pp 211–212 (Eds: JR Wilson, DM Hogarth, JA Campbell and AL Garside), CSIRO Division of Tropical Crops and Pastures, Brisbane.

Koech RK, Smith RJ & Gillies MH (2010): Automation and Control in Surface Irrigation Systems: Current Status and Expected Future Trends, In: Southern Region Engineering Conference, 10–12 November 2010, Toowoomba.

Raine SR & Foley JP (2002): Comparing Application Systems for Cotton Irrigation – What are the Pros and Cons? Field to Fashion, 11th Australian Cotton Conference, 13–15 August, Australian Cotton Growers Research Association Inc. Brisbane.

Koech RK, Smith RJ & Gillies MH (2014a): A Real-time Optimisation System for Automation of Furrow Irrigation.

Irrigation Science, 32, pp 319–327.

Raine SR & Montagu K (2006): Improving Surface Irrigation Application Performance, IREC Farmers’ Newsletter, No. 172, Autumn 2006.

Walker WR & Skogerboe GV (1987): Surface Irrigation: Theory and Practice, Prentice-Hall, New York.

Raine SR & Walker WR (1998): A Decision Support Tool for the Design, Management and Evaluation of Surface Irrigation Systems. Proc.

Walker WR (1989): Guidelines for Designing and Evaluating Surface Irrigation Systems. FAO Irrigation Drainage Paper 45.

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USDA (2009): Farm and Ranch Irrigation Survey (2008). Vol. 3, Special Studies Part 1, 2007 Census of Agriculture, AC-07-SS-1.

USDA (2014): Farm and Ranch Irrigation Survey (2013). Vol. 3, Special Studies, Part 1, 2012 Census of Agriculture, AC-12-SS-1.

WISA (2015): Simple, Smart Irrigation Management. Available online at: www. wisagroup.com [Accessed 23/06/2015].

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water Business

WATER BUSINESS SINGER VALVE CONTROL SYSTEMS sCP-tP Process Controller for automation of Water Distribution systems The SCP-TP Controller is designed to complement a dual solenoid control valve and can switch easily between settings for level control, upstream and downstream pressure management, flow control and position control. The SCP-TP also offers ON/OFF control and can be configured with a 420mA control motor such as the Singer 420 DC pilot-mounted control motor.

The SCP-TP is equipped with easy-to-use digital input controls and user-selectable digital output alarms. Added features such as data logging, which logs all sensor feedback and set-point data as well as

trending graphs, can be used for system analysis for water loss prevention and overall system pressure management.

The SCP-TP Controller reads and compares the process feedback (process variable) 4–20 mA signal to the desired setting (set-point), which is set either locally on touch screen or remotely via 4 to 20 mA signal. The SCP-TP then accurately positions the valve to bring the process variable towards the set-point until they coincide.

The SCP-TP has the capability to retransmit the process variable via a 4–20mA signal and is equipped with both Serial and Ethernet Modbus capabilities for remote SCADA control and monitoring.

420-DC or aC automated Pilot Control Offers Low Power Requirements The 420DC or 420-AC Automated Pilot Control is a reliable, simple and cost-efficient way to automate water systems. The pilot control offers programmable span and speed control via USB cable and software. This innovation allows easy field calibration using a laptop and standard USB connection rather than a custom cable. This reduces the number of wires in the connecting cable to the actuator, making it easier to install. The motor actuator responds to a 4-20 mA signal, rotating the pilot adjusting screw corresponding to the change in signal. The number of turns is adjustable and may be programmed to suit the pressure changes required for the application. With four

different motors and modular boards, parts are easily replaced in the field.

The 420-DC or 420-AC requires less than 2 amps of power to operate, controlled by the 4-20 mA signal from the water distribution SCADA system. The very low power requirement lends itself well to a solarpowered self-contained station. Extended power failure would result in relatively steady pressure at the last setting. Optional freeze or default to high or low pressure is available on loss of signal. With IP68 certification, not only can the 420DC withstand water, it is capable of being totally submerged and still operating to a depth of seven feet for 24 hours. There is also built-in surge suppression for protection against voltage spikes. The closed loop positioning systems offers predicable and repeated accuracy.

For more information please go to www.singervalve.com

LOW-COST ODOROUS GAS SOLUTIONS Increased urban development in many areas of Australia has resulted in reduced buffers between wastewater facilities and residential and commercial properties. Such infrastructure frequently produces odorous gases, which can become a nuisance to nearby residents or, at high concentrations, a safety risk.

In the past, odours from wastewater collection systems and wastewater treatment plants were generally accepted

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water Business by the public. However, the community has become increasingly sensitive to fugitive odour emissions from these sources and now regards odour as a major issue affecting quality of life.

Odour issues are an ongoing problem for the operations personnel, who have to respond to customer complaints at all hours.

Fugitive odour emissions may occur from any of the wastewater conveyance facilities for a number of reasons. At wastewater pumping stations, pressurisation of the headspace occurs above the sewage level in the wetwell with continuous in-flow into the station.

Current practices such as plastic-lined wet-wells, access chambers and main sewers have contributed to accumulation and pressurisation of the gases in the collection system, which if not released and treated in a controlled environment will escape elsewhere in the system, such as at covers and access lids that have not been completely sealed. Operations personnel are hard pressed to find a long-term and costeffective solution to control and mitigate the odours. Considerable time and effort is spent in pacifying sometimes irate customers who want an immediate resolution.

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Biofiltration Systems • Biological treatment of hydrogen sulphide (H2S) and volatile organic compounds • Innovative patented design • Proven H2S removal efficiency >99% • Modular and transportable construction • Small footprint • Low capital and life cycle costs • Long media life (3-5years). No hazardous waste • Environmentally sustainable technology • Complies with WSA121 Industry Standard for Biofilters for Odour Control • Above and below ground systems available

Applications: Control and treatment of foul odours from wastewater pump stations, discharge manholes, air-valve pits, main sewers, treatment plant inlet works

E-mail: info@odatech.com.au www.odatech.com.au

odours….controlled naturally

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A range of odour control methods have been tried to address the management of odour emissions from wastewater collection systems, including activated carbon adsorption, ozone treatment, odour-masking agents and bio-trickling filters. However, these treatments all require high levels of ongoing maintenance and incur high ongoing costs, both in terms of maintenance and frequent chemical and/or media replacement for satisfactory treatment levels. Without constant attention, these systems become unreliable and do not solve odour complaints.

In addition, many of these odour treatment solutions utilise chemicals or produce byproducts that are not environmentally friendly and must be disposed of.

Traditionally, the odour control option with the lowest costs and maintenance requirements were open biofiltration beds.

These beds of biologically active mulch and other organic matter would be built over vents from pump stations and treatment plants, allowing the hydrogen sulphide gas to be oxidised by the microorganisms that live in the biomedia before the air is released to the atmosphere. In peak operating condition, these beds were a successful odour control option. However, the treatment conditions in an outdoor biofilter bed are difficult to control – the systems were prone to drying out, causing the death of the microorganisms that treat the odours, as well as causing cracks that provide a “path of least resistance” for the gas – bypassing treatment. In addition, over time the media would compact, eventually completely blocking airflow and leaving the foul air to leak out elsewhere.

While working at the Water Corporation in Western Australia), OdaTech Managing Director, Ivan de Souza, noticed the shortcomings of open-bed biofilters and set about attempting to find a more reliable solution that would maintain the low-cost, low-maintenance and environmentally friendly aspects of biofiltration.

Through several prototype units the OdaVent biofilter was born. The fully enclosed biofilter units allow treatment conditions to be tightly controlled for the best possible performance, ensuring the media is in uniform and permeable condition and that airflow is spread evenly through the system. A proprietary biomedia mix is used, specifically designed to avoid compaction and to provide the ideal ecological conditions for the microorganisms.

In addition, the patented tiered tray biofilter design prevents water logging and compaction of biomedia and enables a reduction in footprint of up to four times compared to traditional open biofilter beds.

Their modular design allows flexible system footprints and flow capacities, depending on what is required. Biomedia replacement is a simple and safe process, and is only required every three to five years.

No chemicals are required and no hazardous wastes are created.

OdaTech also offers Australia’s only below-ground modular biofilter. The OdaVent MHV can be unobtrusively installed in street verges or on sites where very limited space is available. Between this and the above-ground OdaVent SPSV, OdaTech biofiltration odour control systems can treat odours at water infrastructure facilities ranging from air valve pits to small-tomedium size wastewater treatment plants.

OdaTech’s biofiltration odour control systems are specifically designed for odour and corrosion control of sewer infrastructure and achieve best-in-class 99% hydrogen sulphide removal. Over 50 systems have now been installed across Australia for water utilities such as Water Corporation, SA Water, Gold Coast Water, Brisbane Water and Melbourne Water, and private water recycling companies.

For more information please go to www.odatech.com.au

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water Business HOW IS YOUR GPS TRACKING? GPS can be ubiquitous. It can be used in cars, drones, mobile phones, site machinery and even people. If it moves and has value, then it’s possible to use GPS technology to track it.

GPS works by providing information on exact asset location and is used commercially to track the movement of a vehicle or person. The benefits of using a GPS tracking system are wideranging, with examples such as: • Monitoring the route and progress of vehicles; • Trapping asset location to ensure maximum utilisation; • Reporting on hours and distance travelled of plant and equipment; • Assessing the basic day-to-day activities of an employee work schedule; • Tracking high-valued assets in transit including temperature, impact and light; • Linking vehicle, driver and incident data for speeding fines or accident replays;

• Providing compliance information like fatigue, maintenance and mass management;

later date to provide evidential information.

It can also be used for business planning or to manage inefficient business practices.

• Improving quality measurement information.

One emerging use for vehicle-based devices is to use GPS systems to help provide evidence of vehicle use through pin code or ID tags, trapping drivers to asset use. This is especially important with recent policy changes relating to the ramping up of fines of up to $15,000 where companies haven’t been able to allocate the driver to speeding fines. Other assets can also be tracked using weather-resistant NFC tags and barcodes with the GPS coordinates being tied to the location where the items were scanned.

From a commercial perspective, GPS devices can be used by companies in the water industry to record the position of vehicles and trip data. Using mobile technologies and cloud-based systems, GPS information is easily sent to a centralised database via a dedicated device or within a mobile application on modern smartphones.

The use of smartphones has provided a cost-effective and convenient way to manage a remote workforce, with many improved outcomes over straight tracking devices.

Irrespective of the type of GPS system deployed, the power is in the fact that they are real-time, automatically sending location information and other key data like G-force, speed and engine information to a central point. It’s capable of dissecting and displaying the data in a worthwhile manner and can be extremely powerful by alerting the business of incidents as they happen, or providing data that can be mined to use at a

CLEAN TEQ AIR & AROMATRIX UNITE TO FORM AUSTRALIA’S LARGEST AIR POLLUTION TREATMENT COMPANY

The joining of Clean TeQ Air and Aromatrix Australia, effective the 30th of October 2014, results in two of Australia’s most experienced air pollution control companies combining over 30 years of experience in biological, thermal, activated carbon, scrubbing and cyclone based particulate removal technologies.

To obtain a brochure on the products and services now available to you, send us an email at info@cleanteq.com Clean TeQ Aromatrix Pty Ltd Ferntree Business Park, 2 Acacia Place, Notting Hill 3168, Victoria, Australia p. +61 3 9797 6700 f. +61 3 9706 8344 e. info@cleanteq.com w. www.cleanteq.com

Smartphones have also changed the landscape to allow the tracking and task management of people, such as field workers or project teams. The power of this style of managing staff is that you can do much more than just track. In fact, through intelligent forms and phone sensors you can trap everything you could imagine (and more) including the location. This approach sees a separation in thinking, moving away from cookie crumb tracking to "key moment" tracking where human interaction is measured through common

HYDROVAR®, the modern variable speed pump drive is taking pumping to a new level of flexibility and efficiency.

Call us today to discuss your applications requirements.

Ph: 1300 4 BBENG www.brownbros.com.au DELIVERING PUMPING SOLUTIONS

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Water Business variations going into the secondary and tertiary treatment, further guaranteeing the high quality of this discharged water.

tasks. In the water industry, this can be used far beyond GPS devices allowing companies to extend location to include time-based measurements of activities with locationbased validation.

Imagine running a project that is profitable based on materials used and resourcing allocations. Under these systems, budgeted use of both plant and humans can be tracked along with location, providing powerful knowledge for future tendering and profit management.

However, with the recent updates to the Privacy Act 1988 (Cth) (Privacy Act), all companies should review their legal requirements for tracking and monitoring mobile employees.

So what are the legal requirements for such surveillance? In New South Wales, Victoria, Northern Territory and Western Australia (and under the Surveillance Devices Bill 2014 (SA), the use of a surveillance device to intentionally track and record employee activity is a criminal offence, unless the operator of the system has the consent of all of the parties to the activity. Such consent can be express or implied.

Implied consent can include passive acceptance, where the employee is fully informed. The general requirements for consent are that it must be voluntary, informed, and given to an individual with capacity to understand. Difficulties will arise where an employee withholds consent, and you should seek legal advice where that occurs. In any case, the penalties are significant if human assets are tracked without prior consent.

There is no question that GPS is here to stay. The question is, how are you going to use it for human assets while staying inside the regulations? One tip is work with a company that understands the legal obligations and is able to provide solutions to meet your asset-tracking needs. If you can marry human and asset in one simple-to-use business system that benefits the employees job task, then the ease of employee acceptance might be higher.

Please visit verticalmatters.com.au/civil for more details.

HYDROFLUX HALVES ENERGY COSTS OF BURRA FOODS’ WASTEWATER TREATMENT Australian dairy ingredient processor Burra Foods recently installed a Hydroflux HyDAF Dissolved Air Flotation (DAF) unit for primary wastewater treatment and successfully halved their energy costs. The HyDAF

water august 2015

For more information please go to www.hydrofluxindustrial.com.au

system from wastewater treatment specialist Hydroflux Industrial was chosen over several others in the market as capable of increasing the plant’s treatment efficiency and reducing operating costs.

According to Burra Foods’ Wastewater Treatment Plant Supervisor, Daniel Tsivoulidis, they began to see results at the Korumburra site in the South Gippsland region of Victoria just one week after installation.

“Within a week we were already removing so many of the solids in primary treatment that our secondary treatment Sequencing Batch Reactors did not need as much oxygen. We immediately saw a drop in electricity costs,“ he said.

“With some more fine tuning we saw even more improvements. We reduced our energy costs by almost half, and the Sequencing Batch Reactors can now process double the volume of water.”

Improving primary treatment also leads to improved secondary treatment performance, smoother processes and other benefits according to Hydroflux Industrial’s Director, Mathew Pugh.

“We see this time and time again. Getting the wastewater treatment right at the front end can have an incredibly positive effect for the rest of the plant, as well as significant cost savings. It’s a worthwhile investment with a fast return as it reduces the cost of operation,” Mathew said.

Burra Foods’ HyDAF unit now removes 60–70% of contaminants in a continuous automated process and has shown savings through reduced energy and chemical demand, as well as a reduction in operational expenses in downstream treatment.

The DAF unit also enabled improved pH fine-tuning and there is less downtime now required for washing the microfiltration and reverse osmosis plants that form part of downstream processes.

The Burra Foods site can use up to a million litres of water a day and final treated water is discharged to the environment.

Improved primary treatment reduces water

AMMONIA, MONOCHLORAMINE SYSTEM FOR CHLORAMINATION PROCESS MONITORING Most systems available for online measurement of the chloramination process in drinking water require batch measurement and reagents, which can be counter-productive when a time-dependent process is required. Further, the sample system pumping the reagents can often be prone to mechanical breakdown, resulting in unwelcome downtime that can often render continuous measurement of the process impractical and unreliable.

Emerson Process Management’s new Water Quality Monitoring Panel provides reagentfree continuous measurement of Ammonia (NH3 + NH4+) and Monochloramine, without the need for expensive or messy reagents or troublesome sample conditioning systems.

Further, no calibration with standards is routinely required, just a matrix adjustment against a process grab sample near the measurement point.

The system comprises the Rosemount Analytical 56 dual channel Transmitter, constant head flow controller, Ammonium ISE and Monochloramine amperometric sensor with an optional direct pH compensation.

The 56 Controller has a full colour LCD display, event logger, PID & TPC control, HART® digital communication, four x 4-20 mA outputs fully scalable, four relays configurable as alarms, interval timer, TPC, bleed and feed timer, and delay timer fault alarms.

For further information please visit www.rosemountanalytical.com

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ZINFRA. BUILDING REPUTATIONS

Mike Stokes Renewals and Backlog – Program Manager South East Water “The Zinfra team working on South East Water’s sewerage program on the Mornington Peninsula has been excellent.

Together we are on track to successfully deliver 135km of our 230km sewerage services project to 16,500 properties in 18 months. This is one of Australia’s largest projects of this type to be completed in such an accelerated timeframe.

Working with Zinfra has made delivery of this project easy. The members of the team have remained consistent for the project, making relationships effortless to manage, and they bring extensive experience with large scale, fast-moving pipeline projects to the table.”

www.zinfragroup.com.au