Page 1

AWA

-,

AUSTRALIAN WATER

ASSOCIATION ABN 78 096 035 773

PHE SS UHE WAT SEYYEJV\GE EFFICIEN


entley WaterGEMS V8 XM Edition continues with Haestad Methods' tradition of pioneering research and innovation, advancing the water modelling technology standard once again.

B

ELIMINATE PLATFORM RESTRICTIONS Being anchored to a single platform is costly and risky. WaterGEMS V8 XM Edition is the only solution that lets everyone work within their favorite platform, sharing a single model file.

SHATTER PERFORMANCE BARRIERS Designed to support all-inclusive models, WaterGEMS V8 XM Edition gets a new power boost to build, run, edit, and map large water distribution models with ease, at recordbreaking speeds.

EASIER THAN EVER! The legendary ease of use of Haestad Methods solutions is magnified with WaterGEMS V8 XM Edition. Enjoy a fresh new stand-alone interface, an improved ArcGIS integration, and an all-new MicroStation platform with dozens of new features and ground-breaking utilities:

GD. : I: ,:

l:

~~~ 11D

~~~

• Criticality analysis

• Stand-alone GIS demand allocation

• Network trace queries

• Network segmentation analysis

• Stand-alone Terrain Extraction

• Pressure-dependant demands

• New isolation valve element

• Network navigator

• Variable speed pump batteries

• Centralised wat er use management

• New hydrant element

• Unit demand eng ineering libraries

• Dynamic SOL-based queries

• Auxiliary fire flow results

C!ll

Learn more about the award-winning WaterGEMS VB XM Edition at:

www.bentley.com/AWA Contact us today for more information: Toll-free (Austra lia): 1800 245 005 • Toll-free (New Zealand): 0800 444 046 e-mail: anz.marketing@bentley.com

ENVIRO 08: Visit booth 165 to pick up your FREE Water Modelling Guide CD! May 5-7, 2008 • Melbourne Exhibition & Convention Centre


water

Journal of lhe Austral;an Water Assodat;on

Volume 35 No 4 June 2008

OPINION AND INDUSTRY NEWS

OPINION Time for Australia Water Inc? Water and Electricity Don't Mix My Point of View CROSSCURRENT National, States, Industry, International, People in the News NEWS

DBarnes, President, AWA TMollenkopf, CE, AWA Laurie Gleeson, retiring CEO, Goulburn Valley Water

4 5 8

12 20

PROFESSIONAL DEVELOPMENT WATER EDUCATION NETWORK WICD UPDATE AWA EVENTS CALENDAR AWA MEMBERSHIP ENVIR008 REPORT

26 27 29 30

EA (Bob) Swinton

34

FRBishop

44

SPECIAL REPORT AVision for Water

TECHNICAL FEATURES (~

indicates the paper has been refereed )

WATER EFFICIENCY ~ Demand Management: Recognising Future Challenges How hord will we hove to work to keep demands in check? RBeatty, SO'Brien A National Standard for Water Auditing Effective water savings depends on accurate audits J Schlafrig WESTERN CORRIDOR PROJECT The Western Corridor Recycled Water Project: Part 1. Overview and Update 230 ML/d being recycled for industry, indirect potable reuse and irrigation WTraves, KDavies Part 2. The Bundamba Advanced Water Treatment Plant: Design, Construction and Start-Up High technology delivered fast-track GO'Toole, J Bates, RDagwell, GHattie Part 3. Water Quality Monitoring and Risk Management Ensuring a robust system is developed to minimise risk ARoux, MPirrone, BBowen, TWalker Part 4. Advanced Oxidation at Bundamba AWT The final stage of a gold standard purification train RHowick, AFestger PRESSURE SEWERAGE Pressure Sewerage: The Flinders Project Innovations to meet technical challenges S French INTERNATIONAL ACTION ~ Rural Water Supply for Bali: Off-shore Design by Young Engineers Engineers Without Borders adopt on innovative approach to rural water supply KThird, 0 MFun, J Bowen, AMicenko, VGrey, TProhasky liJ EWB in Action Integration with social structures is the key to success J Bowen WATER SUPPLY Point of Entry Treatment For Rural Supplies Cost effective quality for small communities SGray, EOstarcevic, DDharmabalan, LFiedler, AJayaratne MEMBRANE TECHNOLOGY Fouling In Reverse Osmosis Areview of the chemistry and biology of fouling BBolto, TTran, MHoang SKILLS SHORTAGE Al and the Water Industry - the Next Wave Expanding the capacity of your professional staff PRadcliffe

56 62

65 70 75

79

81

87 91

93

96

100

WATER BUSINESS NEW PRODUCTS AND BUSINESS INFORMATION - SPECIAL FEATURES: RAINWATER TANKS; PRESSURE SEWERAGE ADVERTISERS' INDEX

102 116

OUR COVER Cheryl Batagol, Chair of Melbourne Water and Deputy Chair of Sustainability Victoria, addresses Enviro 08 and heralds a new revolution for sustainability. See report on page 34. Journal of the Australian Water Association

Water

JUNE 2008 1


~ AWA CONTACT DETAILS ~ 'Promoting the swtainable ..~ management ofwater' POSTAL ADDRESS PO Box 222, St Leonords NSW 1590

TEL + 61 2 9436 0055 EMAIL info@awa.asn.ou WEBSITE www. awa.asn.au PRESIDENT David Barnes - president@awa.asn.au

CHIEF EXECUTIVE Tom Mo llenkopf - cbeer@awa.asn.au

CHIEF OPERATIONS OFFICER Ian Jarman - ijarman@awa.asn.au

EVENTS Wayne Castle - wcastle@awa.asn.au

MEMBERSHIP INFORMATION AND ENQUIRIES Michael Seller - 61 2 658 l 3 4 83 mseller@awa.asn.au

MEMBERSHIP RENEWALS AND CHANGES Membership Team - 1300 36 l 426 info@awa.asn.au

MEDIA AND MARKETING Edie Nyers - enyers@awa.asn.au

SCIENTIFIC AND TECHNICAL INFORMATION Diane Wiesner Ph D - dwiesner@awa.asn.au

WATER EDUCATION NETWORK

Journal of the Australian Water Association

Volume 35 No 4 June 2008

ISSN 0310-0367

AWA WATER JOURNAL MISSION STATEMENT 'To provide a print ;ournal that interests and informs on water matters, Australian and international, covering technological, environmental, economic and social aspects, and to provide a repository of useful refereed papers.' PUBLISH DATES Water Journal is published eight times per year: February, Morch, Moy, June, August, September, November and December. EDITORIAL BOARD Choir: Fronk RBishop Dr Bruce Anderson, Hl.A-Enviro Consultants; Terry Anderson,Consultont SEWL; Greg Finlayson, GHD; Dr Brion Lobzo, Vic Health; Professor Felicity Roddick, RMIT University; Mike Muntisov, GHD; David Power, Beca Consultants; Dr Ashok Sharma, CSIRO; and Bob Swinton, Technical Editor. EDITORIAL SUBMISSIONS Water Journal invites editorial submissions for: Technical Papers and topical articles, Opinion, News, New Products and Business Information. Acceptance of editorial submissions is subject to editorial board discretion. Email your submissions to one of the following three categories:

Corinne Cheeseman - ccheeseman@awa.asn. au

NATIONAL SPECIALIST NETWORKS Laura Evanson - levanson@awa .asn.au

AWA BRANCHES: AUSTRALIAN CAPITAL TERRITORY and NEW SOUTH WALES Tanya Webeck - 61 2 9467 8408 actbranch@awa.asn.au, nswbranch@awa. asn.au NORTHERN TERRITORY Hayley Galbraith - 61 2 9467 8419 ntbranch@awa.asn.au SOUTH AUSTRALIA Sarah Carey - 61 8 8267 1783 sabranch@awa.asn.a u QU EENSLAND Kathy Bourbon - 6 1 7 3397 5644 qldbranch@awa.asn .au TASMAN IA & VICTOR IA BRANCH Rachel-ann Martin - 61 3 9235 14 16 tasbranch@awa.asn.au vicbranch@awa .asn.au WESTERN AUSTRALIA Cath Miller - 0416 289 075 wabronch@awa .asn.au INTERNATIONAL WATER ASSOCIATIO N , AUST. IIWAA) iwabranch@awa.asn.au

DISCLAIMER Australian Water Association assumes no responsib ility for opinion or statements of facts expressed by contributors or advertisers.

COPYRIGHT AWA Water Journal is subject to copyright ond may not be reproduced in any format without written permission of AWA. To seek permission to reprod uce Waler Journal material email your request to: enyers@awa.asn .au

2 JUNE 2008

water

1. TECHNICAL PAPERS AND FEATURES Bob Swinton, Technical Editor, Water Journal: bswinton@bigpond.net.ou AND journal@owa.asn.au Papers of 3000-4000 words (allowing for graphics}; or topical stories of up to 2,000 words. relating to all areas of the water cycle and water business. Submissions ore tabled at monthly editorial board meetings and where appropriate are assigned to referees. Referee comments will be forwarded to the principal author for further action. See box on page 4 for more details. 2. OPINION, INDUSTRY NEWS, PROFESSIONAL DEVELOPMENT Edie Nyers, enyers@awo.asn.au, Tel: 61 2 9436 0055 Articles of l 000 words or less 3. WATER BUSINESS Brian Roult, Notional Sales & Advertising Manager, Hallmark Editions brion.roult@holledit.com.au Water Business updates readers on new products and associated business news within the water sector. ADVERTISING Brian Rauh, National Soles & Advertising Manager, Hallmark Editions Tel: 61 3 8534 5014 (direct}, 61 3 8534 5000 (switch}, brian.rault@holledit.com.ou Advertisements are included as an information service to readers and are reviewed before publication to ensure relevance to the water environment and objectives of AWA. PURCHASING WATER JOURNAL Single issues available @ Sl 2.50 plus postage and handling; email dwiesner@owa.osn.au BACK ISSUES Water Journal back issues ore available to AWA members at www.awa.osn.au PUBLISHER Hallmark Editions, PO Box 84, Hampton, Victoria 3188 Tel: 61 3 8534 5000 Fax: 61 3 9530 8911 Email: hollmork.editions@halledit.com.au

Journal of t he Australian Water Association


from the president

Managing Water Assets David Barnes AWA President

It has been postulated that the greatest antique value in the UK is represented by the underground water and sewerage network (defining antique as more than 100 years old}. The Australian pipework is more recent but equally val uable t o the community. It is important that these assets continue to provide the service for wh ich they are intended. This req uires an accurate and reliable understanding of the cond ition of existing physical asset s and robust and transparent processes to repair or replace the assets. The current massive capital programmes in urban and r egional Australia have the potential to divert attention and resources from the existing infrastructure, the value of which far exceeds the value of the current capital projects. For example Sydney Water in its Annual Report quotes 'assets with a replacement val ue of $24 billion', which is considerably larger than the capital expenditure ($0.65 billion) or the total value of the new large desalination plant and infrastructure ($1-2 bi llion). Concurrently much of the major agricultural water supply infrastructure is being upgraded. Open channel distribution sy stems are being replaced with pipes and lined channels, pl us more efficient irrigation systems are being installed.

This commercial approach to the management of assets has been pioneered by the local industry and needs to be more widely adopted both nationally and internationally. Many of the implications of the predicted effects of climate change wi ll place additional importance of the management of assets, for example prolonged dry and wet periods wi ll create greater physical stresses on buried pipes, whi le increased temperatures wi ll accelerate the rate of generation of hydrogen sulphide in sewers with an enhanced potential for sulphuric acid attack on metallic and concrete components. This acceleration in deterioration has serious cost implications because a high proportion of the buried assets are already more than half way th rough a nominal 100 year life. A ret urn to the 'out of sight out, of mind' approach to our heritage of hidden infrastructure will represent a loss in val ue t hat exceeds the current intensive expenditure.

The fact t hat many of these assets are underground or remote means that it has often been convenient to disregard t heir importance and t o under-commit human and financial resources. As a consequence asset management has tended to be less well developed than planning, procurement or customer service (J im Keary, Hunter Water Australia at Singapore International Water Week). The importanc e is reflected in the accounts of any organisation with long lived assets. The provision of funds to account for asset depreciation is one of the largest figures in the balance sheet. Hence changes t o the asset life, particularly of buried asset s, have a significant (positive or negative) effect on the profitability of water companies. The Australian and New Zealand approach to asset management is widely regarded as worlds' leading best practice. The conventional risk based approach formu lates a mat rix of consequence and likelihood to identify individual as sets in high or extreme risk categories. The risk profile can then be used to rank and schedule the replacement or renewal of each asset. Th is has been augmented to be centred on a business case methodology in which all costs and benefits are computed - economic, fi nancial, social and environmental. For ex ample, by including the economic costs of traffic disruption and consequent delays caused by road closures due to a burst main. Investments can then be justified once the benefits of replacement or renewal exceed the costs. This approach can be demonstrated to save substantial cost particularly by not replacing sound assets.

4

SEPTEMBER 2008

water

regular features


from the chief executive

As Ye Sow ..... Tom Mollenkopf AWA Chief Executive As part of AWA's visual identity 'refresh' I recently reviewed our new membership brochure. It had a lot to say about the benefits of membership and what AWA does for its members: professional development & training, conferences, seminars, technical workshops, publications and journals, advice, national and international connections, industry programs and advocacy. The list goes on. But I digress; it is not my intent to market AWA services and products (well, at least not in this column). What struck me was t hat what is arguably t he most important and rewarding aspect of membership - active invo lvement or volunteering - was harder to articulate in the prospectus. Like many associations, AWA's history and future is inextricably linked with a strong spirit of volunteerism. At a purely logistical level, we would not be able to deliver the breadth of services and events, not do so as cost effectively as we do, without t he hard work and ski ll of the membership around the nation. Whet her through Branch Committees and working groups, Conference Program committees and Specialist Networks, every month thousands of hours of time is donated freely and enthusiastically by AWA members in the cause of fosteri ng knowledge, understanding and advancement in sustainable water management. It is something that I and the Board of AWA are immensely proud of and thankful for. Fortunately, this investment by members is not a one way street. There are tangible benefits t o members from active involvement in AWA activities. This can range from the personal satisfact ion associated with helping deliver a worthwh ile program, advancing understanding or influencing policy development through to raising ones professional profile. Some members develop new skills and competencies through running events or programs or are able to take leadership roles; others wil l be engaged in extending their technical knowledge; and, of course, there are the benefits of fellowship and extending networks.

It seems to me from all this that much of AWA's value is in the opportunity it offers water professionals and organisations to do things, rather than just be delivered services. To paraphrase the late JFK, "Ask not what your association can do for you, ask what you can do for your association" ultimately it will be an even greater reward. Or to use a somewhat o lder source: As you sow, so shall you reap. On a serious note, the importance of our volunteers cannot be understated and I for one say "thank you." It is one of t he roles of the small team in AWA's National Office and our Branch Managers to ensure that, as far as possible, we give you the support that you need and deserve. Wh ile we are talking about membership, it is pleasing to note that at a t ime when many membership based associat ions are losing members, AWA continues to grow. Last financial year saw a growth of just on 10% in membership numbers. These figures and more wi ll be included in the AWA Annual Report, which is currently being compi led and will be released in time for our Annual General Meeting, which is scheduled for late October in Sydney. The final report is still subject to Board review and approval, but the likely o ut-turn will be a small financial surplus for the year based on a fulsome program of activity and achievement. And, saving the best until last, it is a pleasure to cong ratulate one of our number on receiving one of the world's most prestigious water prizes. At the International Water Association's World Congress in Vienna t his month, Dr. Jim Gill, Managing Director of Water Corporation in W.A. wi ll receive the IWA Grand Award. The award recognises outstanding ach ievement in the water sector; in Jim's case for his leadership in confronting the impacts of climat e change o n water services. AWA looks forward to celebrating this achievement with Jim and other Australian delegates to the Congress at a reception at the Austral ian Embassy in Vien na. International success has some compensations!

One of AWA's current projects, our Mentoring Program, springs to mind by way of example. Mentoring is generally considered to be intended to benefit the 'Mentee', i.e. the less experienced professional who can be coached or guided by their Mentor. Such a program relies on the good wil l and time of mentors. Interestingly, the anecdotal feedback I have received is t hat Mentors often consider they get as much value from t heir mentees as the mentees get from them. Mentors find the questions and ideas that are put to them can be challenging and enlightening. Similarly, as they offer their own t houghts, they are called on to more explicitly articulate their rationale and may take the chance to critically evaluate their assumptions and positions. And sometimes t he interactions are even fun.

water SEPTEMBER 2008 5


letters to the editor Water, Electric Power, Emissions and Climate Change In the June edition of Water, AWA CEO Tom Mollenkopf stated that water and electricity are closely linked. He wrote, "Some of the largest areas where electricity is consumed is in pumping water and wastewater or in operation of water treatment and wastewater treatment plants". He went on to remark that both the water and electrical sectors are making substantial advances in developing sustainable approaches and that the water industry, " .. . has done remarkable work in developing and adopting new technology .... " , including utilising more efficient pumps. The water industry's remarkable work mentioned by Tom seems to have one glaring omission in my opinion. The technology to reduce aerator grid power consumption by displacing conventional aerators used for mixing in wastewater treatment plants by solar powered mixers has been available for many years. Indeed, the Nhulunbuy Waste Stabilisation Ponds project powered by solar powered near-laminar flow mixers won the John Wellard Sustainability Award in July 2006. A Darwin based engineering firm brought together, "sunlight and innovative technology" to significantly improve the effectiveness and sustainability of waste treatment ponds for the township of Nhulunbuy.

Submitting Letters The AWA Water Journal Editorial Committee encourage your feedback on articles featured in the Water Journal, or on issues affecting the water sector. Letters should be less than 400 words, and if referring to a specific article, provide the issue number, page and article title. Please include your full contact details with letters, and email to journal@awa.asn.au or fax (02) 9436 0155.

Traditional mixing options were considered by the engineering firm , but rejected in favour of solar. Results were reported to be remarkable. Dissolved oxygen levels increased throughout the depth of the lagoons, problems with stratification, odour and blue-green algal blooms did not reoccur, effluent quality increased and sludge levels decreased. In spite of the results achieved with this project, solar powered mixers appear to have been ignored by the Australian wat er industry, even though similar reductions in energy use and therefore greenhouse gas emissions are being achieved in wastewater treatment plants in North America in all cl imate zones. Many well documented case studies have been published that demonstrate the effectiveness of solar powered mixers in red ucing energy requirements while improving plant performance. Furthermore, the same solar powered mixers being used in wastewater treatment plants can be used in fresh water reservoirs to enhance water ecology including prevention of algal blooms and increased DO levels. Solar powered mixers have other beneficial features; capital outlays are lower, installation is fast, no additional infrastructure is required and maintenance costs are minimal. Why then the reluctance of the Australian water industry to adopt this technology? Asset management has been put forward as one reason. Are working aerators to be displaced when they have years of life left in them? Operating and maintenance costs need to be balanced against replacement costs for sure, but if we believe there is a need to red uce the water industry's energy use and greenhouse gas emissions in both absolute and relative terms, perhaps the industry needs t o bear these costs? Wastewater treatment plant operators certainly ought to be pressuring their engineering consultants and providers to consider not only the energy cost savings that can be made by using solar powered mixers when upgrading treatment plants or building new ones, but also the savings in capital costs, installation, infrastructure and maintenance. Providers of conventional aerators won 't like it, although some "pure" aeration will be required until new, more energy efficient technology replaces these as well. Introduction of new technology resu lts in winners and losers, but the real winners are those that can adapt to change. The water industry can't afford to indefinitely stay with old, energy hungry aerator WWTP mixing technology, but needs to adopt new sustainable solar tech nology when the opportunity arises. Harvey Gough, MRACI CChem, novasys group pty ltd

6 SEPTEMBER 2008 water

regular features


A VISION FOR WATER Compiled by Frank Bishop, Chair of the Journal Committee Since Biblical times, the world has been challenged with the Four Horses of the Apocalypse - pestilence, famine, war and death. Today we could perhaps add climate change, which could trigger all four events. Climate change and its impact on water resources presents a major challenge for the world, in particular Australia. While disparate views may be expected on issues, there is a commonality among public and private organisations in the water industry on the need for planning for climate change, carbon trading, water conservation and reuse, and overcoming the skills shortage. While there are many problems there are opportunities that can be accepted by innovation and good management. We have asked some leaders in the water industry for their vision on how Australia will solve its water resource problems.

THE PUBLIC UTILITIES

N ick Apostolidis, Director of GHD a nd Water Business Stream Lea der I was recently asked by rhe Editorial Board of the Water journal whether I would be interested in interviewing public sector CEOs in the water sector to identify key issues and their vision of the water industry in Australia. It was particularly pleasing char mo st CEOs we approached, despite very busy schedules, were prepared to share rhei r views and vision for the industry and I trust you find the following insights as interesting as I have.

Challenges There were some common themes bur each had sligh tly different rake, appropriate to rhe geographic region and type of business.

Adapting to Climate Change was a key theme with most CEOs. Perhaps most aptly put by Kerry Schorr, CEO Sydney Water Corporation , who said, "the Australian water u riliries are at rhe front line having to deal with climate change in a practical manner right now." As well as having to improve water supply security, uriliries are findin g they have to cope with more frequent violent climate act ivity causing power outages that last longer, p urring pressures on service levels. Warmer climate combined with lower water storage levels is encouraging more algal blooms and

44

JUNE 2008

Water

changing raw water chemistry, requiring further treatment upgrades as well as additional operating costs from higher chem ical and energy use. Most water uriliries in Australia have implemented or are well advanced in implementing portfolio strategies, a combinatio n of demand and supply side solutions, to add ress water supply security. There appears ro be universal acceptance char chis approach is rhe best way to provide an acceptab le level of water supply security in a climate change affected world. Each major capital city is able to point to good progress o n demand management, leakage control, development of climate independent sources of water such as desalinatio n and water recycling as well as grids that allow more flexib ility and effe ct ive utilisatio n of existing and new sources of water. The gen eral consensus from the CEOs I spoke to is that once all the above capital works are implemented, rhe water security issue will be largely overcome for some period of time.

Achieving an Equitable Balance in Allocation Several CEOs, especially those that rely on the Murray Darling as their primary source of water supply, have to deal with complex social, political and environ mental issues around allocatio n of water. An n H owe, CEO SA Water, wh ose utility is perhaps most impacted by the Murray Darling allocation issues, sees the techn ical challenges are relatively easy compared to "finding a balance of on what is equitable and reasonable when dealing with co mpetition for water between urban and rural comm unities, poor and rich. " D avid Stewart, CEO of GoulburnMurray Water, is observing significant stress in rural communities. Ir is a major social iss ue and shou ld not be overlooked in d ealing with these commun ities.

Journal of the Australian Water Association

Murray Smith, CEO Coleambally Irrigation Co-operative Limited is concerned with government participation in water t rading and its imp act on the price of water. Whilst he acknowledges there are some areas where irrigation is nor viable and rhe purchase of water allocation is app ropriate, there are many areas where irrigation is operati ng at best practice levels and delivering economic benefits to the region and Australia. Many CEOs of urban utilities believe that wh ile they have done a good job on demand management and improving system efficiency, they would like to see more effort in demand management and improving irrigation efficiency in rhe rural sector.

Skills Shortages Almost every CEO, both public and private sector, u rban or rural, expressed some concern about rhe skills shortage and their ability to deliver the plan ned capital programs and to adequately operate and maintain their assets in the fucure. WSM recently published a report char showed that with the combination of increase in capital spend and an ageing workforce there will be a shortage of about 8000 workers by 2017 covering the fu ll spectrum of disciplines in the water sector, from engineers to trades, lab technicians and administrative staff. The co ncerns are somewhat varied. The public sector appears generally concerned about the ability of the industry to attract and retain sufficien t skilled resources for rhe ongoing operations, as well as the significant loss of knowledge char is occurring as many of rhe baby boomers in their workforces head towards retirement. Also of co ncern is rhe co mpetition for talent from rhe booming mining sector char is offering much higher salaries than the water sector can sustain in rhe lo ng term.


MAKIN G MODERN LIVING POSSIBLE

VLT® AQUA Drive - extended power range to 1.2 MW The ultimate solution for water, wastewater & irrigation Danfoss Drives applied its unsurpassed experience in advanced drive technologies to ensure the new VLT~ AQUA Drive is t he perfect match for all ac motor driven appli cations in water, wastewater & irrigation systems.

VLT• AQUA Drive incorporates "water" specific hardware and softwa re features to provide total system hardwa re & whole of life operating cost benefits and is supported by local experts in over 100 countries world wid e.

0.25 kW - 1.2 MW power range Compact enclosures with segregated cooli ng EMC fi lter & DC Bus chokes built-in Advanced harmonic filter options Save on system & installation costs Protect equ ipm ent & piping Save energy Red uce operating & m ai ntenance costs

For further details please contact your local Danfoss Drives specilist:

Me lbourne:Tel. (03) 9703 5 100 · Sydne y:Tel. (02) 8845 1800 • Brisba ne:Tel. (07) 3630 1899 • Adela ide:Tel. (08) 8150 7400 Pe rth: Tel. (08) 9333 3800 , Auckland: Tel. 64 9 259 2500 • Christchurch: Tel. 64 3 365 6 123

www.danfoss.com/pacific • Email: motioncontrols@danfoss.com.au


Managing Complex Systems The introduction of climate-independent sources such as desalination, advanced recycling and third pipe systems will require a new breed of operators with more advanced skills to manage these assets. J im Reeves, CEO Brisbane Water, is concerned that in the current environment, the water utilities are not able to match the salary levels offered by the private sector, in particular mining companies, to attract sufficiently skilled people to operate the more complex systems they have developed.

A Shift to Market Based Institutional Arrangements Several state governments are reviewing the current institutional arrangements with a

view to move towards a market-based model similar to the electricity sector and some rural water schemes. Under these arrangements water will be valued at the market race rather than the cost of service. The CEOs recognise char there is some momentum behind chis move and are now looking at how co best respond to these new arrangements.

Increasing Energy Costs Economic growth, commitments to CO2 emission targets and renewable energy targets all point to higher energy prices in future. This will have a major impact on cost of operations as energy is a key cost input for most water utilities.

Water Quality Ian Tanner, Acting CEO Sydney Catchment Authority, believes there will be a renewed focus on water quality once the drought breaks and the water supply security issue eases with additional treated water sources available. The multiple sources of water itself poses some interesting water quality challenges for authorities that are purchasing water for the same customers from differenc sources. This is a key issue in SEQ where new operating rules are being developed to cope with different suppliers of water and different entities involved in delivering the product to the final customer.

Vision Despite the challenges posed, the CEOs I spoke with were generally positive about the future of the Australian Water Industry and its ability to deal with the challenges. David Stewart (CEO Goulburn-Murray Water) said "This is the most exciting phase the water industry has been in for decades. We have an opportunity to make a long term difference to the sustainability of the nation."

Public and Private Sector Working Closer Together CEOs from both private and public sector were unanimous in their view chat co deliver the massive capital works program planned over the next 10 years will require a more collaborative approach to project delivery. Rob Skinner, CEO Melbourne Water, said "we will see a move to alliances to pool the best private and public sector experience and resources." Peter McVean, CEO Veolia, observed how the situation has changed from 15 years ago. "Back then organisations such as Veolia were looked upon as poachers but today we are seen as partners."

Better Long Term Planning The clear lesson from the past decade is that we need co plan better for climate extremes. There seems to be universal acceptance now that clim ate change is a real ity and future solutions should aim to avoid adding to the carbon footp rint. Rob Skinner, CEO Melbourne Water, noted the need for more innovative approaches to planning, perhaps incorporating an El Nino impact every three to four years .

Diversity Will Be the N orm Murray Smith, CEO Coleabally Irrigation Co mpany, observed "D iversity is the key.

46

JUNE 2008

Water

Journal of the Australian Water Association


For information on our Airlift MBR system please contact Australia - 02 9918 5088

leading in purification

Singapore - +65 6338 9919

WWW.XflOW.COm


We will see m o re em phasis o n a m ix of enterprises to manage risk. An nual crops still have a role, particularly where reliab ility of supplies is fu rther impacted by climate change." "Secu rity T hrough Diversity", "Fou r Taps Policy", "WarerFutures", "Metropolitan Water P lan" all em brace a d iverse approach to achieve water su pply security. In a cl imate change world chis d iverse (portfolio) approach to water supply security will become rhe norm.

Great Demand for Australian Skills and Experience

Shaun Cox, CEO South East Water, sees the creation of smarter cities embracing integrated water managem ent/water sensitive urban design principles, such as smart metering that p rovides water and energy use in for m ation to customers that help them manage their usage more efficien tly. Sue Murphy, General Manager Water Corporation, sees better engagement w ith commu nities and creatio n of vibrant com munities with landscapes and plants appropriate to the local climate and soil condi tions.

THE PRIVATE SECTOR

Carbon Trading, Renewable Energy Targets and CO2 Emission Offsets T he introduction of carbon trad ing, renewab le energy targets and government com mitments to red uce CO 2 emissions will change the way we manage and develop water infrastructure in futu re. Several u tilities have already committed to ach ieve carbon neutrali ty. Fo r example Melbourne Water has co mmitted co become carbon neutral by 2018, Syd ney by 2020, m y own o rganisation by 20 10 . M any more organisations both p ub lic and p rivate are now co mmitting to sim ilar object ives . Ross You ng, CEO WSM said "In fu ture we may look at wastewater treatment plan ts as water facto r ies and energy generation planes rather than facilities for creating sewage".

Next Generation of Water Conservation Programs Mose of the water u tili ty CEOs were very proud of their achieve ments in water conservation but were not resting o n their laurels and are looking at the next generation of Water Co nservation measures. 48 JUNE 2008

water

And th e futu re? Well, it's here already and I would like to mention th ree areas that I chink will define o ur next 10 years. First, due to drought we are now seeing large scale application of memb rane technology. Fo r our company alone by the end of next year we will be managing plants with 700 ML/d combined production capacity of advanced water treatment, recycl ing and desalination using membrane technologies - UF/MF and RO. Seco ndly, historically th e industry's focus has been o n water quality and demand m anagement. Recent times have seen water resou rces and the creation of new sources as the main focus. These must remain but there is now recognition that asset m anagement perform ance in water has lagged behi nd industries such as oil and gas. Mention "process" in the past and it was usually t reatmen t p rocesses being talked abou t. Now, it's information p rocesses and how we cap ture and use it.

It is my personal view that the solutio ns being im plem en ted by Australian water util ities, in adap ting to cl imate change, will be in demand all over the world. Australia's experience is being closely watched and this provides a great opportunity for all rhe organ isations currently involved in regulation, plann ing, p rocurement, design, co nstruction and operation to export t heir skills and servi ces to the rest of the world . T he o pportunities apply to both the urban and rural sector. Murray Sm ith, CEO Coleam bally Irrigation Co-operative Limited stated "When people visit fro m overseas they say we are leadi ng che wo rld in ou r app roach to irrigation management and we shoul d be selling chis know-how overseas."

asset custod ians and concern for pub lic health and transparency must be front and centre.

Peter M cVea n, CEO, Veolia W ater Australia .

Public-Private Participation, Membrane technology and R&D Veolia W ater signed its first contract in Australia in I 994 with Sydney Water for two Build-Own-Operate water treatmen t plan cs. This was fo llowed in 1996 by the 15 year Adelaide ou tsourcing contract. Veolia Water now has 22 long term con tracts across Aust ralia and New Zealand and ove r 700 staff. Over those 14 years there have been enormous changes in che water industry from institut ional and pricing refo rm to dealing with d rought and climate change . From my perspective o ne other majo r change has been where the private sector fies and how it contributes to water in Australia. In the mid- l 990s there was concern from the pu blic sector that water would fo llow the sam e path as in the UK with wholesale asset privatisation . We have never p ushed this ap proach ; tho ugh depen d ing on the circum stances a case can be made for private fina ncing of new in frastructure. My perceptio n, and hope, is that we are now seen and understood as a valuab le partner, and an integral part o f the ind ustry, not an outside p redator. O ur business is abou t lo ng term partnersh ips . For this to work there needs to be not on ly professionalism and service b ut also mu rual respect and trust. We are all

Journal of the Australian Water Association

Finally, the broader chall enge is to see how the private sector can contrib ute across the broader water cycle in integrated catchm ent managemen t: in sou rce develop ment and protect ion, stormwarer cap ture, sustainable urba n design , recycling and reducing ou r carbon intensity. For all o f chis co happen, there needs to be commitmen t co R&D and development of peop le. We have had a local commitment to R&D since ou r firs t co ntracts. Th is has co ntinued throughout rhe years and we are now pleased to be co-fundi ng the Un iversity of Q ueensland's C hair in Water Recycling. Another challenge w ill be how the pu blic and p rivate secto rs work together to deal with rhe growing peop le sh orrage as rhe boomers leave and skill requirements change . Boch pares of the ind ustry need to work together in attracti ng and retaining talent. We recogn ise chis w ith initiatives such as U nited Water's long standing Grad uate Development Prog ram an d our current project to establish a memb rane tech nology centre in south ease Q ueensland to serve nor just our needs, but needs across the AsiaPacific region. le is a truly exciting time to be pare of the Australian water industry. We face challenges bur are also in many respects lead ing the world. We ho pe to cont inue to contribute and keep Austral ia at the fore front.


~\.OY~~

Ji.~~OO

There are many benefits you can gain if your employees are Reservists. Navy, Army and Air Force Reservists learn ~ that there is often a better way to do something and have a committed desire to lead others with confidence, ~ maturity and responsibility. They develop a range of new skills and impart their knowledge to others and are always keen to find a better way to get the job done, thereby contributing to your bottom line. What's more, by showing your support to your Reservist employees, the Employer Support Payment Scheme can provide financial assistance of more than $1 ,000* per week, which may be used for offsetting the costs of releasing Reservists for duty and paying for replacement staff. Discover how your business can be enhanced if your employees are Reservists, and learn about the benefits and obligations you have as an employer. With a range of other support services also available to you, you'll soon see how a Reservist can make all the difference. Find out more - call 1800 803 485 or visit www.defence.gov.au/reserves

DEFENCE RESERVES SUPPORT

¡ cond1t1ons apply V1s1t WWW defence gov au/reserves for further dela1ls

Australia's Reserve Forces


EVALUATION OF PROTECTIVE

SewperSpray & Sewper Cost effective, easily applied by


SEWER LINING SYSTEMS

Coat Repair Mortars trowel or spraying wet or dry

formerly Lafarge Aluminat es Australia Pty Ltd

Kerneos Australia Pty Ltd Tel: (02) 9498 5288 Fax: (02) 9498 5311 E-mail: greg.tucker@kerneos.com


technical features

water efficienc ~

DEMAND MANAGEMENT: RECOGNISING FUTURE CHALLENGES R Beatty, S O'Brien Abstract This paper examines the drivers of water demand in the light of work undertaken in a number of urban centres around Australia. Investigations include the analysis of residential water consumption in different suburbs of Sydney and Brisbane, the analysis of trends in customer consumption in a number of other cities and towns, and the water dem and outcomes fo r co mmunities with third pipe systems. The paper then discusses the challenges presented in achieving meaningful reductio ns in per cap ita water use, particularly after drought restrictio ns are lifted . Ir includes a discussion of water pricing policy in addition to examining rhe futu re for retrofit, rebate and regulatory programs. T he paper concludes by ou rlining rhe strategy and policy implications for our dem and management efforts.

Introduction The last 15 years has seen a tremendous rare of change in rhe management and delivery of urban water services in Australia. The 1990s saw major changes in pricing st ructures and as we entered the new m illennium, we entered a drought that has caused us to questio n traditional approaches to rhe management of supply and demand. W here once we would be seeking to build new supply infrastructure to meet rising per capita demands, we are now almost routinely exam ining the role of reducing demand in providi ng a future balance between supply and demand. T here has been a universal acceptance of the importance of water price in encouraging more effi cient water use and with much of Australia's urban population experiencing the worst drought on reco rd, restrictions on water use have been in regular use.

Proportion of Australian Households with Efficient Fixtures and Rainwater Tanks 90% ~ - -80%

----------------------------,

Dual Flush Toilet ~ Water Efficient Shower Head ~Rainwater Tanks

1/)

!! 70% 0

.,

.r:

!!l

60%

0

:i:

]

~

0

50% 40%

C:

~ 30%

8.

e 20%

Q.

10% 0 % + - - - - ~ - - ~- - - - - - - ~ - - - - - - - - - - - - - - 1992 1994 1996 1998 2000 2002 2004 2006 2008

Year

Figure 1. Proportion of Australian Households with Water Saving Fixtures and Rainwater Ta nks (figures from ABS, 2007). Given that there have been so many changes in water pricing and significant periods of water restrictio ns in the recent past, understandi ng current trends in demand has become more problematic. M anagi ng future demands is a major challenge, firs d y b ecause we have so litde understanding of the factors influenci ng demand and secondly, because we have only recenrly started to implement demand management programs and have had litde

Uncertainty Over Water Demands Prior to the current drought and the accompanying water restrictions, it was clear that in spite of the increasing water effi ciency of many water-using fi xtures and appliances, lifestyle and in com e factors have been worki ng against those trends to put a counter-balancing, upward pressure on per

Sydney - Flats and Units Consumption 200

...

180 路

:J' -

~ ~

160 路

e 140

Demand Management Program

ll.

8_ C:

0

~ E

:,

120

!!'

100

Ii ~

80 路

C:

(.)

ii

I

~I

C/)

0

How hard will we have to work to keep demands in check?

or no time without water restrictions to observe their impact.

60 路

~i

> a:

I I!

a:

.; :,

C: C: <(

40

----

20 0

---------

- - . - - - - - - , - - - ~ - - - ~ - - ~ - ~ - ~ - ~ - - - ---.------<

! , -

1990

1991 1992

1993

1994

1995

1996 1997

1998 1999 2000

2001

2002

2003 2 004

2005

2006

Year Ending June

This paper is an ed ited vers ion of th e presentation to rhe Water Effi ciency Conference, March 2008.

56 JUNE 2008

water

Figure 2. Water Consumption in Flats and Units - Sydney 1990/91 to 2004/05 (adapted from Sydney Water, 2005).

Journal of the Australian Water Association


technical features refereed paper

cap ita demands (Beatty, O'Brien and Stewart 2004).

Proportion of Installed Front Loading Washing Machine Stock 25%

T he recent drought and the acute fo cus on water conservation have seen significant chan ges in the way we use water. More and more Australian households now report the ownership of more efficient toilers and showerheads (Figure 1). There has also been an increase in the use of rainwater ranks.

-+- New South Wales -

20%

.,

-+-Tasmania

'0

0 s::; 15%

., s::; .,:::,

0 :i::

The impact of restrictions for ou tdoor uses h as been significant. However, presumably at so me point in th e fu ture, dams wi ll begin to refill perhaps nor on the back of the abundant scream fl ows seen historically, bur with a co mbination of reduced d emands and additi onal supply sou rces such as recycled water and desalination plants. Restrictions on water use will be eased, although it looks as though low level restrictions may be a permanent feature of our water management future. Water prices will almost certainly be higher in real terms, co reflect the coses of future supply optio ns, such as desalinatio n.

Victoria Queensland South Australia . _ Western Australia -

Northem Territory

-

ACT Australia Power (Queensland)

0 10% ';!I.

5%

0%

-1------....---"T"-----,------~---,-----,----,--- ~

Jan-93

Jun-94

Oct-95

Mar-97

Jul-98

Dec-99

Apr--01

Sep-02

Jan--04

May--05

Date

Figure 3. Load Capacity - Washing Machines (data from Energy Efficient Strategies, 2006).

Load Capa city - Washing Mach ines

si--:======:::;------------~------- -7 -<>- Top Loaders

-o- Front Loaders Twin Tubs

The key question facing us will be how

hard will we have to work to keep demands in check? One of the key risks we face as an indust ry is misinterpreting part of the impact of water restrictions as permanen t reductions in water use. If we cake the example of Syd ney in the restrictions of the mid 1990s, water consumption in some sectors rebounded to levels high er than chose before the restrictions. An example of ch is can be seen in the 1996-2001 increase in demand per dwelling for flats and units (Figure 2). This h ighlights another important point - which is chat in the fu ture we ca n ill afford to allow customers co be shielded fro m the impact of water pricing by allowing strata unit development to continue to meter on a corporate basis. I c is clear chat we need a much better understanding of the fun damental drivers of d em and if we are going to manage demands effectively in the future.

Water as Just Another Consumer Good? Water is in some ways a unique consumer good. In spire of it bei ng relatively cheap, there is a strong negative sentiment attached to its waste or over-use, driven no doubt by the strong links between water extraction and waterway health . With che more pressing ch allenge of climate change, we are n ow just starting to chink of energy use in a similar way. T he unfortunate reality is chat, in sp ire of the strong sentiment chat water is more

o+------.-------------------------,----~ 1992

199â&#x20AC;˘

1996

1998

2000

2002

2004

2006

Year

L

Figure 4. Load Capacity - Washing Machines (Energy Efficient Strategies, 2006).

Proportion of Australian Households with Air Conditioners and Dishwashers 70% ~ - - - - -- - - - - - - -- - - - - - - - -- - -- - - - - - - ,

60%

"'

-0- Air Conditioner -<>--Dishwasher

'0

10 50% :::, 0

:: 40%

!0

30%

C:

0

:e8, 20% E

ll.

10%

0%~ , - - - - - - - - - - - - - - - - -- - - - - - - -- - - - - - 1 1992 1994 1996 1998 2000 2002 2004 2006

Year

Figure 5. Proportion of Austra lian Households with Air Conditioners and Dishwashers (figures from A BS, 2005).

Journal of the Australian Water Association

Water

JUNE 2008 57


technical features II.

water efficienc ~ "sacred" than other goods that we consume, we are still a consumer society. As our incomes and aspirations rise, we rend to consume more, and this is true of water, which provides us with many conveniences and luxuries. This is also true of the waterintensive nature of many of the goods and services that we consume. The markets char are vital to bringing us these goods and services, dutifully fo llow our rising appetite for resources. In rhe United Scares, where the Energy Act o f 1992 introduced point of sale control on rhe maximum flow rare for showerheads (2.5gal/mi n), we are now seeing multiple showerhead fixtures being offered for sale. Closer to home, we are increasingly purchasing more efficient washing machines (Figure 3), bur one litcle recognised fact is that while we are moving to these more efficient machines, the load capacity of machines is increasing (Figure 4). In spire of concerns about both global warming and water supply security, the proportion of households with air conditioners and dishwashers is steadily rising (Figure 5).

The Impact of Rising Incomes There has been a significant amount of research into the impact of income on water demand. Studies in Syd ney (Montgomery Warson, 1995) and Brisbane (MWH, 200 6) both show char rhe level of water demand in different areas of a city can be predicted accurately on the basis of a range of demographic and socio-economic facto rs, one of them being household income. Such analyses provide rhe ability to explore the impact of rising incomes such as chose seen throughout Australia in recent rimes (Figure 6). By formulating scenarios of different income rises, the impact on demand can be gauged direccly. Another feature of this type of analysis is char rhe implied income elasticity of demands in d ifferent areas can be estimated (Figure 7). Unsurprisingly, rhe richest suburbs of a city have the highest income elasticities, with rhe poorest suburbs having rhe lowest.

Will Global Warming Increase Demand? There is a scientific consensus at the current rime that under current climate change scenarios, the areas of Australia char currently host our most populous cities will experience both higher temperatures and lower rainfall. This will result in an increase in water demand in the medium and longterm, as well as the adverse impact on the reliab ility of surface and some groundwater supplies. The increase in water demand can

58

JUNE 2008

Water

refereed paper

Real Household Disposable Income

., ;f"

'iii'

$40,000

"'i-1

S35,000

~

S30,000

c:, c:, c:,

.fl

.. ..8.

·a 0

S25,000

E

S20,000

.,"

..

S15,000

&. en

S10,000 ·

£:

j;;ii

0

.E

:E

-<;- NSW -o- Victoria Queensland

en

South Australia -:c:-Western Australia ~ Tasmania -+- Northern Territory -<>-Australian Capital Territory Australia

c

:!:!

..

S5,000

0

.c en

:, 0

so

:r

1994/95

1995/96

1996/97

1997/98

1998199

1999/2000

2000/01

2001/02

2002/03

Figure 6. Real Household Disposable Incomes - Austra lia 1994/95 to 2002/03 (ABS). Implied Income Elasticities of Demand • Sydney ls!cal Government Areas 2.0

-. --------------------ill;!;-__________......, >,

(/)

1.8

~

z 1.6 ·

-~ 1.4

"

~

.!!! 1.2

., g 1.0 " ] 0.8

UJ

C:

ii .§ 0.6 0.4

0.2

Figure 7. Implied Income Elasticities of Demand - Sydney Local Government Areas. be quantified with the use of the multivariable regression equations underlying commonly used climate correction models. Figure 8 shows the results of such an analysis carried our for Brisbane. I r sho~s increases in total per capita demand of up to 10% for different climate change scenarios.

Third Pipe Systems One of the answers being put forward to reduce per capita demand is the use of recycled water through "third pipe" systems with recycled water currencly being in plentiful supply, However, there will be limitations to such supply in future. Firstly, due to the perceived high cost of providing treatment to supply demands in peak periods, recycled water systems are often designed to meet only average d ay demands. In addition, it is typical fo r

Journal of the Australian Water Association

communities to have high seasonal peak demands. This will not be a problem where emerging communities can tap into the wastewater produced in adjoining communities, but ultimately when the supply of recycled water becomes limited, there will be a need for storage to meet seasonal demands. In many areas where there are strong seasonal demand variations, this will be quite a significant volume, with co nsequent cos r. Secondly, there is a significant body of "end-use" modelling work underpinning estimates of the reductions in water demand from the application of third pipe systems. Unfortunately there has been little work in confirming the assumptions used. There is a significant proving effo rt being undertaken for rhe Pimpama-Coomera development o n rhe Gold Coast, and the analysis of recycled water supplied to residential properties in


technical features

water efficienc ~ Sydney O lympic Park is showing some surprising results. The residential co nsumption per property for potable and recycled water is shown in Figure 9 and Figure 10. They show char: • There is little o r no climare influ ence in the potable use - which indicates a h igh level of compliance with the use of recycled water for outdoor use; • Recycled water use shows strong seasonal patterns - indicati ng its use for irrigation; • While the residential customers in the Sydney Olympic Park WRAMS supp ly area have not been subject to water restrictions, there was a noticeable downturn in demand fo llowing an effort by Syd ney O lympic Pa rk Authority SO PA ro encourage customers ro use water more wisely in 2004. O f more interest is the total consumption per accou nt. G iven char che development supplied by SOPA is a new subu rb and that t here has been a strong emphasis in che development of the suburb on sustainabil ity, the volu me of potable water use is somewhat higher than chat predicted by end-use modelli ng. Predicted end-uses of water were estimated usin g results from the Yarra Valley Water Studies in 2004 (Yarra Valley Water, 200 4 and 2005) and adjusting fo r the exp ected d iffe rence in appliances and household size in the Syd ney Olympic Park supp ly area. Observed potable uses were 6% higher than chose pred icted with end-use modelling. Possible reasons for this include:

700 ~

2,

., "'

::, ~

!

~

600

500

!!

.

·a. 400 (.)

., ~

a..

- - - - - ~ --

., 300 ·= .; ."' ,,ID 200

-

Global Warming Case 2

-

12 per. Mov. Avg. (Historical Case)

100

-

12 per. Mov. Avg. (Global Warming Case 2)

!u :;; I!!

-Historical Case Global Warming Case 1

12 per. Mov. Avg. (Global Warming Case 1)

a..

0

~ ~

~

~

;!.

~

~

~

Figure 8. Impact of G lobal Warm ing on Predicted Dema nds (Beatty an d O' Brien, 2007). Residential Single Dwelling Potable Water Use - Sydney Olympic Park WRAMS 600

'o'

2~

C:

500 400

:, 0

u u

c(

~ consumption

300

per Account

--- ~1{~~1ed Consumption

8. 200 aE

Residual

C:

0

:,

"'C:

Climate Corrected

100 ·

0

(.)

• That the study participants in the Yarra Valley Water studies were not typ ical water users - perhaps by virtue of the face chat t hey participated in the study (the so-called "self selection" problem); and,

• An unkn own n umber of customers in the supply area may not have retained the lowfl ow showerheads and water-efficient taps.

refereed paper

-100 .,___ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ Sep- Dec- Mar- Jun- Sep- Dec- Mar- Jun- Sep- Dec- Mar- Jun- Sep- Dec- Mar- Jun- Sep-

m m m m m m

~

~

~

~

Mar- Jun-

m

__J

Figure 9. Residenti al Potable W ater Use - Sydney O lym pic Pa rk WRAMS - July 2002 to June 2007 . Residential Single Dwelling Recycled Water Use - Sydney Olympic Park WRAMS

500 ,------------;::::========;------, -0- Consumption per Account (Uday)

~

-

~ c:, 0

While efficiency of use will p lay an im portant pare, it is becoming increasingly clear char to redu ce per capita demands we will n eed a balanced suite of measures - and many chat specifically target the u pward p ressure o n water demands . An o utline o f each of these measures is provided below.

Dec-oo m

Quarter Ending

T hese results emphasise the importance of proving work to verify the forecasts of outcomes for alternative water servicing strategies.

The Challenge in Reducing Per Capita Water Demand

m m m m oo oo oo

400

Predicted Consumption

Residual Climate Corrected

300

u u

c(

8_

200

C:

0

aE :,

100

"'0 C:

(.)

Water pricing There has been a long-held sentiment in the water industry chat the retail p rice for water is "coo cheap" ro encourage efficient water u se. G iven char th e total revenue received by water utilities broadly approxi mates their costs,

m m m m m m m m m m oo oo oo oo m m -Dec--~-Dec--~-~-~-Dec--~-Dec--~ ~

~

~

~

Quarter Ending

Figure l 0. Residentia l Recycled W ater Use - Sydney Olympic Park W RAMS - July 200 2 to June 2007. Journol of the Australian Water Association

Water JUNE 2008 59


technical features refereed paper

there are upper limits to the total volume of revenue chat can be gained from water use. There are two mechanisms chat water utilities use co increase the conservation signal in water prices: 1. To increase rhe proportion of revenue gained from water usage charges; and 2. To introduce inclining block tariff structures so chat higher users are penalised more severely for their excessive water use. I t is typical for water utilities to recoup 50% of their coses from water usage charges. More recently, some water businesses are increasing chis co 75%. From a purely economic perspective, it would be difficul t to argue chat further increases in rhe proportion of water usage-based revenue are justified, given chat th e cost base of m ost water utilities includes a significant p roportion o f ice ms chat are independent of the volume of water delivered - even if we take into account the marginal coses of future supply capacity. To increase the proportion of revenue gained from volumetric changes makes a utility increasingly vulnerable to revenue losses in times of drough t. If the volumetric charges are above the long run marginal cost of sup ply, the shore run revenue losses from

the implementation of demand management programs may exceed the benefits (leading to a need co further adjust water prices). The restructuring of tariffs with inclining blocks has a significant potential to induce changes in water use, but it can be argued chat an across-the-board price increase would target a much greater proportion of use. T his is because there is often a relatively small volume of water consumed under the highest tiers. In addition, as we have seen from the analysis above, chose in the highest consumption tier will most likely have a less elastic respo nse to water prices. Scarcity p ricing has som e potential to increase the strength of the price signal, although much work needs to be d one co ensure that the delivery of water is not stratified into different levels of service for the "haves" and the "have-nots".

residential and non-residential custom ers.

In the short-term, the water savings impact of such programs is abundantly clear. W h at is uncertain is h ow these water savings are m ainta ined in the medium to long-term. To dace, little research has focused on longterm retention.

Regulatory approaches Regulatory app roaches have been used to increase the water efficiency of new and refurbishing development. These include the requirements for more water efficient fixtu res and appliances (includ ing point of sale control) and the installation of rainwater tanks and third pipe systems.

In addi tion to these limitations to pricing structure changes, there is the problem of increasing incomes, which by their very nature erode the pricing signal.

T he key to maximising the benefits of regulatory programs will be to induce a high level of compliance, both in the shore and long-term. As shown by the discussion above, there will always be a certain proportion of users chat will find ways to circumvent the impact of regulations, and these water users will continue co be a challenge, both now and into the future.

Retrofit, rebate and audit programs

System water losses

There have been many successful retrofit, rebate and audit programs run by water utilit ies across Australia targeting both

While it is becoming increasingly co mmon for Australian water utilities co have system water loss management programs, th ey are

... Data Collection & Reporting Hosting, processing & backing up your data You access via the web Data is sent from a datalogger in the field Reports include dynamic trends & calculations Operational decisions made quick & easy Sites being monitored can be permanent or temporary Historical & current data at your fingertips A cost effective solution to distributing data Retrieve data from office, home or any internet connection Email and/or SMS real-time alarms

HydroShare is an effective solution

for your data collection

-----'US' Utlllty Services

20 Corporote Drive, Heotherton Vic 3202, Australia

P (03) 9552 3007 F (03) 9552 3008 E info@usus.com.au

www.usus.com.au

60 JUNE 2008

Water

Journal of the Australian Water Association


technical features refereed paper

There is also a need to establish water accounting frameworks such as che one we are embarking on in South East Queensland. These fram eworks need to facilitate the capture, screening and analys is of data, and the automated tracking of climate-corrected trends. They utilise readily available databases, GlS and starisrical analysis approaches to put the data management, analys is and forecasting tools needed to manage water demands into the hands of chose who need them.

still in a minority and much more work needs to be done. Many water businesses in Australia are operating with levels of leakage well above the economic optimum. There needs to be an increase in the investment in the planning and implementation of such programs. Measures include pressure reduction, active system leak detection and rehabilitation.

Source substitution There was a view held for many years char source subsricucion alternatives such as rainwater ranks and recycled water were not cost-effective. What is inceresri ng is char while this view was commonly held, developers, local government and water utilities started to implement chem anyway. This was driven by strong perceptions about the environmental value of such approaches, in addition to increasing standards for environmental discharge of wastewater, which in many cases exceeds the quality of water required for recycled water use. There is a growi ng body of work char has shown char rainwater uses may be more cost-effective when considered from a "coral system" perspective.

We need to move away from our reliance on "good news" stories as a substitute for good quality srraregic planning for our water futu res. If we are relying on demand management savings for our fucure supply security, then we need che long-term outco mes to march the rhetoric that focuses on the next electoral cycle. We also need to focus on investment in Australia char harnesses Best Practice planning and implementation approaches. For rhe benefits it provides - in terms of effective long-term increases in su pply capacity - fund ing for the planning, implementation and management of demand management programs is srill generally a fraction of char spent on capital investments for increasing supply-side infrasrruccure.

One key issue is considering the opportun ity afforded by new development in avoidi ng the need to undertake more expensive retrofits ar some rime in the fucure. By "hard-wiring" water efficiency into new development areas we stare to reduce the number of dwellings and businesses char are designed for high water use.

The Authors Russell Beatty is National Knowledge Leader, Water Sustainability, MWH Australia email Russell.bearcy@ au.mwhglobal.com; Shane O'Brien is

Conclusions and Policy Implications In conclusion, there are many challenges in bringing about meaningful reductions in per capita demands in Australia. With uncertainty about the drivers of demand and rhe impact of climate change, it will certainly not be a case of just picking rhe "low hanging fru it". In most cases there wi ll a need for some serious tree shaki ng if we are to reach our demand management goals. We will also need the full suite of measures at our disposal. These include all of chose on the demand management side, but also those on the supply side. In the current environment, ir is puzzling to see decisions by all governments wich the exception of Queensland to summarily dismiss potable reuse of wastewater as a long-term option fo r enhancing water supply security.

Technical Director, Planni ng and Policy, MWH Australia.

References Australian Bureau of Sratistics (ABS), 2005, Environmental Issues - Peoples Views and Practices, March 2005 Australian Bureau of Statistics (ABS), 2007, Environmental Issues - Peoples Views and Practices, March 2007 Beatty, R., O'Brien, S. and Stewart, B. (2004) Per Capira Water Use and its Implications for Demand Management, Water, June 2004 Beatty, R., and O'Brien, S. (2007), Sustainable Urban Water Cycle Management - Building Capacity in the Australian Water Industry, Ozwater 2007, Sydney, March 2007 Energy Efficienr Strategies 2006, Greening Whitegoods, A Report into the Energy Efficiency Trends ofMajor Household Appliances in Australia.from 1993 to 2005. June 2006 Monrgomery Watson, 1995, Sydney Water Supply Strategy Phase 2 - Demand Study, December 1995 MWH, 2006a, Brisbane Water- Development of Water Demand Analysis and Forecasting Models, Occober 2006 MWH 20066, South East Queensland Regional Water Supply Strategy Integrated Urban Water Management and Accounting Task Group WMAO 1 - Water Needs and IUWM Opportunities Investigation. Report I: \1:1/ater Accounting Framework and Systems Review, November 2006 Sydney Water Corporation (SWC), Water Conservatio n and Recycl ing Implementation Report, 2004-2005 Yarra Valley Water (2004), 2003 Appliance Stock and Usage Patterns Survey Yarra Valley Water (2005), 2004 Residential End-Use Measu rement Study

New Turbidity and Chlorine Meter from H~NN~ ,

Hl93414

TIJ",: ~Turbidity : /J: fer

Features • • • • • •

Free or Total Chlorine range - 0.00 to 5.00 mg/L (ppm) Turbidity Calibration - 2, 3 or 4 point Chlorine Cahbration - 1 point Turbidity Method - Ratio Nephelometric Method (90°) Light Source - Tungsten filament lamp, user replaceable Turbidity Range -0.00 to 9.99: 10.0 to 99.9: 100 to 1000 NTU auto-ranging • LOG memory - 200 records, with time AND location • Serial Interface - USB 1.1 and RS232 Tel: Fax: Email: Web:

+61 3 9769 0666 +61 3 9769 0699

hannains@hannainst.com.au www.hannainst.com.au

I H~NN~

instruments

Journal of the Australian Water Association

Water

JUNE 2008 61


technical features

A NATIONAL STANDARD FOR WATER AUDITING J Schlafrig The Need For environmental protection, conservation of national water resources, economic performance of industry and economics of the utilities, there is a need for a standard for water auditing. This wo uld also assist in the identification of water industry/government roles. There is so much diversity in the use of "auditing" for non-domestic consumers in the water industry that a panel representing the major states with regulated water management plans was convened at the Water Efficiency conference in March.

The Panel: J ohn Brennan (Water Corporation, representing WA), Damian Connell (City West Wacer,rep VIC), Andre Boerema and Sally Armstrong (Sydney Water, rep NSW), Mohan Senevirame (consultant, formerly Director Water Efficiency, Queensland Water Com mission (previously Program Manager 'Every D rop Counts' Business, Sydney W ater), rep QLD), Tom Tyrrell (ACTEW, rep ACT), Mathew Green (SA Water, rep SA). Moderator: John Schlafrig, Water Efficiency/Conservation Consultant (Water Conservation Group) and former water resource regulator (WAWA and Water & Rivers Commission WA).

Current Developments in the States Western Australia (John Brennan Water Corporation) Western Australia commenced with a thorough audit and water saving campaign in Perch and Kalgoorlie in 1996 which led to very substantial savings in Kalgoorlie (18%) and Perth (11.5%) in the overall non-domestic sector. Water Corporation has identified nondomestic users using greater than l0ML/a and the WA Government requires these to complete and implement a Water Management Plan acceptable to Water Corp and Dept of Water.

Victoria (Damian Connell - City West Water) Victoria's Water Management Plans (waterMAPs) have been mandated for the top 200 water users for all three major urban retailers AND regional utilities. This

62 JUNE

2008

Water

was increased to all users greater than 10ML/a statewide when restrictions went from Stage 3 to Stage 3a. C ity West Water established a comprehensive water conservatio n program (Water Conservation Solutions) that allows custo mers to self-audit their sites and develop and prioritise detailed water efficiency opportunities. Part of this program includes qualified service providers (water auditors) who registered through a tender process. Many of these water auditors can assist customers to develop the mandatory waterMAPs where customers were unable to develop chem 'in-house'. A key part of the Water Conservation Solutions program is the WacerMAP (Water Management Action Plan) which has been rebranded by the Department of Sustainability and Environment (DSE) and d istributed to the other Victorian retailers for wider application.

New South Wales (Andre Boerema Sydney Water) Sydney Water was probably one of the first authorities to conduct audits, starting in I 999. However, at the rime, customers were not required to rake any action. This has now been supplanted by mandatory action. The program of "Every Drop Counts" was managed by Mohan Seneviratne before he moved to Queensland. A program of water audi ting was established in 2001 and WMPs became mandatory for users consumi ng greater than 50ML/a in 2005.

Queensland (Mohan Seneviratne - QWC + consultant) M ohan Seneviratne reported that mandatory water efficiency audits for the non-domestic sector came into force in South East Queensland after the introduction of level 5 restrictions. Businesses were required to save a minimum of 25% of their 2004/5 water consumption. The process of managing the audit process was the responsibility of the

Effective water savings depends on accurate audits.

Journal of the Australian Water Association

local government councils. One reason that under level 6 restrictions businesses were the main focus was that the expected water savi ngs didn't materialise. A key factor was the requirement for sub metering was not stressed and most businesses didn't install them. Without sub-meters the water audits and the associated water savings were of questionable value. T his loophole was addressed under level 6 restrictio ns.

ACT (Tom Tyrrell -ACTEW) ACTEW.AGL audited some 100 schools in 2000 by invitation and at no cost to the customer. Two weeks data was logged, particularly identifying night leakage. T he rest of the audit was 'walk-thru'. In 2007 free audits were performed fo r selected industries and commercial buildings . The reports were given to managements but only a few took action. From late 2007 four large users are presented with current logging data by web-site.

South Australia (Mathew Green - SA Water) The Business Water Savings Unit of SA Water commenced operations in July 2007 and Matthew indicated that some auditing had been carried out.

Summary The Panel identified the fo llowing issues for discussion: • Focus on the top percentage of nondomestic users • Qualitative assessments versus quantitative audits • Competency training • Water management plan requirement and implementation • Metering • School audits • Walk-thru assessments The analogy of energy and environmental audi ts with the water 'audit' was raised . These industries had established standards through SM (Standards Association of Australia), IE Aust and EMIM. For energy auditing che SM has a standard describi ng the process and format and the IE Aust accredits auditors. Environmental auditors are accredited state-by-state by the


technical features

environmen tal regulators using the process adopted by EMIM of having lead and support audi to rs. Water 'audits' presenrly carried out can be anything from a low level assessment or a walk-rhru review co a full y-fledged quanti tative audi t with full measu rement of screams and a data 'closure' . Despite rhe wide divergency of applications (ranging from caravan parks ro oil refi neries), rhe terminology and standardisation of process appears necessary to es tablish quality and consistency of 'auditing'. Nicole Patterson from Barwo n Water enqui red if there was any fo rmat fo r auditing reports. T heir major consumers were quite diverse and assessments or audits needed ro be as simple as poss ible. She was advised char there were two reference books, one by Ho, Mathew and Sturman (Water Co nservation and Audi ting) and one by Mohan Senevirarne (A Practical Approach ro Wate r Conservation fo r Co mmercial and Industrial Facilities). Templates have been developed to varying degrees, Victoria for instance had a T emplate originating at City West Water and adopted by DSE.

desalination , payback periods will be reduced. He himself co nsidered chat che wo rd 'audit' was only applicable if rigorous closure is feasible. He preferred 'survey', or 'assessment', which would be more acceptable by industry. He made the point char che aim was ro save water, not use more paper.

National Standards and Benchmarks General discussion identified char national standards were un iversally desirable. There was a majority who thought che CWW, now the Victorian DSE template, fo r waterMAPs was universally applicable and co nsideration fo r ics adoption nationally or modification fo r national adoption was highly desirable. So me discussion regarding benchmarking suggested chat benchmarking for ind ustries was possible bur dangerous if rigidly applied since there was so much diversity. However, specific indicators such as kl per tonne product, or per number of hotel beds can be developed. Ipswich Council have set standards fo r Best

Practice for such ind ividual items as cooling rowers and vacuum pumps in their own jurisdiction. Cooperation with NABERS, the industry standard for benchmarking and measuring the environmental performance of Australian build ings (managed by the NSW Government's Department of Enviro nment and Climate Change, on behalf of federal and stare governments) could be usefu l. T he NABERS racings complement che benchmarking compiled by Cicy West Water, Yarra Valley Water and South Ease Water in 2007.

Training/Competence T he wo rkshop identified that there was variable competency in preparing both audits and WMP's and there would be major benefit in providi ng co mpetency training. The national perspective was chat training was definitely des irable in rhe stares that had mandatory Water Management Plans to be developed and im plemented. Accred itation of che audi to rs or ind ividuals/organisations involved in

Implementation Currently fo ur scares have mandatory water management plan requirement fo r develop ment AND implementatio n. WEMPs, waterMAPs and Water Management Plans are all the first regulatory step to improve water-use efficiency so these, also, need better and national defi ni tion The iss ues of pe nalties versus incentives and fu nding were discussed by the audience. Reluctance ro outlay substantial capital fundi ng was che major reason fo r co nsumers not to proceed. CWW has offered co-funding fo r innovative projects with a large degree of success and has also funded R & D projects, through RMIT, Victoria and Deakin Universities. T he possibility of tax deduccabilicy fo r capital outlays should be explored. Boch John and Mohan concurred char rhe water audit report was useless unless rhe fi ndings were implemented. Guenter Hauber-Davidson from che Water Co nservation Group agreed chat an audit wasn't self-ful fill ing buc was only a means to an end. Subsequent implementation of water saving actions was essen cial. However, implementation had ro be on a commercial basis as well as environmentally sustainable, which was difficult when che dollars saved could be trivial compared ro che cash flow of chat industry, however, as water prices increased due co the cost of

• • • • •

Australian designed and manufactured. Feed rates from 0.002 - 100 m3thr. Accuracy 0.5%. Industrial and Food Grade Finishes. Suitable for Powders, Grandules, Chips and Flakes. Stand alone or systems available.

Acromet (Aust) Pty Ltd VIC: Ph: (03) 9544 7333 NSW: Ph: (02) 9647 2432 E-mail: chemex@ acromet.com.au

www.acromet.com.au Journal of the Australian Water Association

Water

JUNE 2008 63


technical features

WMP's was uncertain at chis stage. The spectrum of competency in these areas was wid e, the reaso n being that traditional consultants had fa irly narrow tech nology demands and a full spectrum was difficult to maintain in the one organisation. In the industry itself, staff had diverse responsibilities and had limited traini ng in the diverse tech nologies under their responsibility.

Procedures for an Audit

Joh n described the Western Australian history of short cou rse training of service/ providers and consultants and the undergraduate units now fully established at Murdoch Un iversity since 1999. He also describ ed the negotiations between RMIT and the Victorian Government suggesting that a short course co uld commence soon in Victoria.

• Install appropriate flow measurement and data logging to establish demand trends

A representative of the Victorian Department of H ealth asked how this course migh t fir or interface with the drinking water t raining course in Victoria . J ohn advised that RMIT saw the water audi tor and waterMAP training co urse firri ng alongside this estab lished course and both would be led by P rofessor Felicity Roddick. Training coul d be offered to a number of people to enable chem to carry out audits and management plans to a standard format and process. They could include: • Co nsu ltants • Service providers • I ndustry staff, for in- house initiati ves • Reviewers, normally from water utilities or water boards/companies, to assess compliance and value-adding to water efficiency improvement • Regulators, who needed to identify progress towards improved water-use efficiency and justification for allocation of increased water resources.

Accreditation

• Review sire data to identify data measurement and water systems including drawings o f the sire, pipe layouts and flow diagrams • Discuss sire d evelopment p lans to identify increased demand for water

• Record sire data with cameras, drawings augmenting existing data as necessary • QUANTITATIVE AU DIT: measure or calculate flows to achieve a balance (WA notionally adopted I 0% clos ure as an indication that flow data was accurate and nothing had been omitted)

• Group/Expression of Interest The AWA is well placed to call Expressions ofinteresr into individual membership of the n ational steering committee. The model at state level is to invite the stakeholder organisations (identified as resource regulator, utilities, I rrigation Australia, environmental regulator, local governmen t, mining, consultants, plumbers, educators, land developers) to participate under the chairmanship of th e water resource regulator to oversee state competency and application train ing and outco me quality control.

• QUALITATIVE: (Advanced or basic) measurement of major flows to determine potential savings

Tertiary education providers co uld be invited .

• Identify potencial water savings or water efficiency improvement options

Conclusions

• Price the water savings o n existing or future water tariff srrucrures,over the next five or so years • Price the cost of measures • D etermine payback rime based on company economic criteria • Recommend water effi ciency improvemen t for BOARD adoption • Raise fina nce (include grant applicat ions or interest free loan arrangements) • Implement program with BOARD support • Monitor performance by water management team appropriately co nstituted . Water Management Plans involved the latter half of the above bur necessitated che implementation of the water management p rogram.

Action From Here:

T he accreditatio n of water auditors or persons competent to lead Water Management Plans (WMP) teams was seen as q uestionable at this stage but possibly essential in the future if WMPs in fou r stares (NSW, VIC, WA and QLD) did n't progress adequately or were of inferior standard. T he process was seen as short course trai ning in each state then a competency assessment at the end of the course. This would qualify as a support auditor or WMP ream member followed by fi eld experience to establish or qualify the individual as a ' lead' auditor or WMP ream lead er.

64 JUNE 2008 Water

Ir was agreed that the seeps in a water aud it were to:

natio nal steering co mmittee was established. This would address the two areas, water auditing and WMP development and the reporting/process aspects of these.

• Process To establish the process a steering group was required and this could be estab lished through a combination of WSM and AWA calling for expressions of interest to serve on the steering committee or the specific subcommittee for water auditing/WMP development. NWC could be involved. The respective state 'models' can then be evaluated to adopt a national model

• Workshop A larger wider-ranging workshop is necessary and could be convened once a

Journal of the Australian Water Association

The conclusions of the workshop were: • A further expanded workshop on water auditing and WMP developmenr was suggested. • AWA should facilitate with water resource regulators for the establishment of short courses in water audit processes • The national perspective was that monitoring of the perfor man ce o f WMP, warerMAP, WEMPS needed some twelve months before assessment could identify the need for n at ional accreditation of lead auditors. • Whatever the rigour of an audi t, it would be wasted if its recommendations to save water were not implemented due to the client's reluctance to outlay capital expenditure. This can only be overcome by either: - ready and easy access to funding to make projects happen or - the pricing of water need s to increase to drive change or - regulations need to be introduced even if governments see this as stifling business

The Author

John Schlafrig is Technical Manager/Water Savings for the Water Conservation Group Pry Ltd. Formerly he was Project Manager, Water Efficiency at Water & Rivers Commission WA, email: joh ns@watergroup.co m. au.


THE WESTERN CORRIDOR RECYCLED WATER PROJECT PART 1. OVERVIEW AND UPDATE W Traves, K Davies Abstract The Western Corridor Recycled Water Project in South East Queensland is one of the world's largest advanced water treatment projects. Delivered by Western Corridor Recycled Water Pry Ltd on behalf of the Queensland Government, the project as a whole will have the capacity to recycle 232ML/d of water for industrial use, indirect potable use and possibly irrigation. The project is scheduled for co mpletion by the end of December 2008. This paper provides an update on the status of the project by May, 2008, key issues that have arisen in ch e delivery of che project and a comparison of che project with similar international acti vity.

Introduction

- ~~-~""' ....~,

â&#x20AC;˘

- -¡--

At a total cost of $2.4 B, the Q ueensland Government is constructing the Western Corridor Recycled Water Project. This proj ect is one of che most significanc water recycling projects in the world, supplying water fo r industrial use (predominantly cooling) and indirect potable use. It is also the single largest recipient project of fu nding from the Australian Water Fund, with a total Co mmonwealth contribution of some $408M. Secondary created was tewater is fu rther treated at three advanced water treatment plants using microfiltration, reverse osmosis and advanced oxidation to produce what is termed purified recycled water. The water is piped through approximately 200km of large diameter pipelines and numerous pump stations, with about half of the length of the pipeline ch rough existing urban areas. Stage IA of the project was completed in August 2007, with Stage I B scheduled for completion by June 2008 and Stage 2 by

230 ML/d being recycled for industry, indirect potable reuse and irrigation.

WTP

~~.,._.....,,..,

N

A

~pipN,MMM)0...,,.:00,

Figure 1. The WCRWP Concept. the end of December 2008, with a total capacity of 232ML/d. This wi ll have been achieved just rwo years afte r the first works were commenced at the Bundamba sire, and just 30 months after the basic co ncepts were es tablished.

Project History For some years, local and state govern menc in South East Queensland (SEQ) have been contemplating future water resources fo r the region. In 2004, Stage I of the SEQ Regional Water Supply Study concluded that the ex isting major sources were probably adequate to around 2020, although there were shortfalls to be addressed on the Gold Coast and in Toowoomba. The study highlighted, however, that the region was heavily dependent on a single source (Wivenhoe Dam) and that diversification of supply sources should be given further serious co nsideration. Concerns about supply availability grew in 2005, as the currenc drought starred to

have a more visible effect. T he R egional Drought Strategy was initiated in May 2005, and in the meancime estimates of yield of major sources were revised downwards as a result of various factors. Contingency planning was comm enced, considering various "low-flow" scenarios and how these might affect the region if they eventuated. One of the contingency projects was to recycle effiuent from major wastewater creacmenc planes for industrial use. In particular, che plan at chat time was to recycle water to che Swanbank and Tarong Power Stations, wh ich together were using arou nd I 0% of the region's total water resource for cooli ng purposes. The Commonwealth Govern m ent provided fund ing for the preparation of an initial business case by Ipswich City Council and, later, the Queensland Governmenc. This was predicated on the supply of recycled water for industrial purposes but also for a dual-pipe system co service a major new urban growth area to

Journal of the Australian Water Association

water

JUNE 2008 65


technical features

the sou th ofl pswich chat h ad been identified in the SEQ Regional Plan. T here was a shortage of available land in SEQ, and the "Western Corridor" was (and still is) seen as a significant growth area to house che region's growing population. The "Western Corrid or" name remains with the project, although now it is largely a misnomer. This work was com p ieced in lace 20 05 and demonstrated th at the project had the potential to add significanrly to rhe region's water supp lies. Additional resources were commissioned to develop the concep t design and procurement strategies in M arch 2006 . T he concep t in rhe b usiness case was to develop only Stage 1 in che first instance. T his involved th e transfer of effluent from four western wastewater treatment plan ts to Bundamba for treatment using microfilcracion, with che treated water to be transferred to the two power stations. Stage 2 was intended to add water from the major wastewater treatment planes at G ibson Island and Luggage Point, bur chis was seen as being some years distant. By April 2006, however, the fail ure of the wee season became a significant concern, and che government began pursuing rhe "whole" project, includi ng Stage 2. A concept design report (which varied significanrly from the original business case) was issued at the end of Apri l 20 06 and chis formed rhe basis of rhe cu rrent project, which is described in Figure 1.

Indirect Potable Reuse Conceptually, indirect potable reuse (IPR) has been part of the project since the early business case in 2005. Stage 1 only had sufficient water for power station use, however, and there was nor su fficient water for potable reuse. Derailed consideration of potable reuse could be deferred to Stage 2.

Stage

Date

lA 1B

August 2007 June 2008 October 2008 December 2008

2A 2B

Design Capacity (ML/d)

Total

Water

20 46 116 50 232

Water Treatment Process The basic water treatment process adopted across the project comprises: • coagu lation • microfil tration • reverse osmosis

in Toowoomba in mid 200 6 . The resulting "no" vote meant char there remained considerable uncertainty about whether or not IPR would become a reality. By lace 2006, with the drought growing more severe, th e Queensland Governm ent began to speak more widely about the prospect of IPR . A plebiscite was plan ned for March 2007, but when the wee season again fai led, rhe Governmen t decided to proceed with IPR and the plebiscite was cancelled .

Water Quality Objectives T he requirement to use rhe water for indirect potable reuse has largely determined the water quali ty objectives for the treatment processes being applied at the Advanced Water Treatment Planes. T he specifi ed objectives are based o n che health values p rovided in the Australian Drinking Water Guid elines (ADWG) . Release to Wivenhoe Dam has also been an im portant consideration in p rocess design . There are a nu mber of parameters most signifi canrly nutrients - where the requiremen ts for environmental release are much more stringent than the ADWG. The project has targeted a long-term total nitrogen of less than 1.0mg/L an d a total phosophorus concentration of less than 0.lmg/L. Use by power stations for cooling p urposes has also been considered. Cooling water circuits typ ically concentrate water constituents because of che evaporation and recycling of the water, particularly leading to a concentration of heavy metals. Mera! concentratio ns acceptable under the ADWG are somet imes higher than can be

When the concept design was further developed in April 2006, chis was done so as "nor to preclude" the introduction of IPR if chis became necessary. Originally, chis was based on Table 2. Project Time-l ines. delive1y of purified recycled water to Somerset Dam, but chis was lacer AWT Plant Capacity changed to Wivenhoe Dam, which is less distant from rhe advanced Stage One water treatment plants but closer to Bundomba lA 20 ML/day the region's major rericulaced water Combined stage l A & 1B 66 ML/day intake at Mc Crosby in Brisbane. Stage Two This was being do ne agai nst the Luggage Point 2A 66 ML/day backdrop of ongoing argument in Gibson Island 2A 50 ML/day Toowoomba about indirect potable Gibson Island 2B 50 ML/day reuse, and a referendum was held 66 JUNE 2008

used efficienrly in cooling water circuits.

Table 1. Design Capacity by Stag e.

Journal of the Australian Water Association

• advanced oxidation • stabilisation The process was established during concept development to meet high water quality standards. O riginally, two-pass reverse osmosis was adopted but rhe p roject has since reverted to single-pass because the additional creacmenc step was not necessary to achieve the water quality objectives. One of ch e primary drivers in the selection of reverse osmos is membranes was nitrogen rejection efficiency to meet che low nitrogen requirements in the treated water. This is somewhat unique. Advanced oxidation (in th is case ultraviolet ligh t and hydrogen peroxide) was in cluded as an add itional treatmen t step although some major projects (Newacer in Singapore, for example) do not include ch is. Apart from creating an add itional process barrier, advanced oxidation also removes li ngering NDMA (a known carcinogen) in the water, much of which is created during the chloraminario n process ahead of the membranes. There will be some scope for optimising operation of the advanced oxidation p rocess after completio n.

Project Staging The p roject is being delivered in four stages. Stage I is the "original" scope, delivering water from che AWTP at Bundamba to che power stations at Swanbank and Tarong. Stage 2 delivers sufficient water to supplement flows into Wivenhoe Dam. Design capacity is summarised in Table 1.

Delivered volumes w ill depend upon the volume of created wastewater available, wh ich has reduced steadily d ue to the immediate and li ngering impact of water restrictions. The Delivery date projected production volume as at March 2008 is about 131 ML/d at August 2007 the completion of Stage 2A, based June 2008 on Level 5 water restrictions (Table 2). If flows revert to the levels experienced prior to severe water October 2008 restrictions in South Ease October 2008 Queensland, chis is expected to December 2008 increase to around 200ML/d.


technical features

One feature of rhe delivery schedule is char the dares for completion of each stage are nominated by legislation. T his has led to some significant imperatives in achieving the required rimeframes.

Procurement Methodology One of the unique features of rhe project is the fast-track approach to co ncept development, derailed design and construction. The project is being delivered in just 30 months from concept to completion. Ir was identified at an early stage chat chis could not be achieved through conventional delivery strategies, especially against the backdrop of a very right construction marker. This was one of three mu lti-billion dollar public infrastructu re projects comme ncing at about che same rime. An "alliance" approach has been adopted for detailed design and construction del ivery, but due to the scale of the project and the nature of the market it was split into five all iances: three treatment plant alliances and cwo transfer system all iances. T hese are roughly equal in value (Table 3). T he all iances have provided a flexible delivery strategy char has all owed the project concept to evolve during project delivery. This has been an essential feature, and the flexibil ity of rhe alliances to adj use their scope as work has proceeded has delivered major benefits. In particular, che performa nce of che alliances is closely aligned to time performance and chis has assisted in achievi ng che overall legislated cimeframes for completion . The existence of five separate all iances in some ways compromises the "true alliance" model, in the sense chat there is inevitably a group of people who have to ensure that the

Figure 2. 1000 mm and 1200 mm G RP pipelines being lai d. work between the alliances is properly coord inated. For the WCRWP, this is che "Project Management Group", which because of its close linkages to the Stace has also taken on che responsibility fo r land acquisition, environmental approvals, highlevel community consultation and corporate commu nications. Another interesting feature of project delivery has been the parallel del ivery of rwo or th ree other major pipeline projects in the region - all of which are being del ivered through the State Government. le was identified early in che project chat these projects would scare co compete in the pipe supply market, and the Scace Government established a centralised pipe procurement unit within che Department of Infrastructure and Planning to address chis.

This has allowed rhe prioritisation of resources on a regional basis, and has also provided the scale of purchasing necessary to encourage the involvement of new vendors. This has included some 60km of large diameter (1000mm and 1200mm)

Table 3. Project Al liances.

Project Monagement Group Veolia Woter Australia (Operator) Evons & Peck (procurement and project management) The Peron Group (project management) GHD (land, environment, engineering) Phillips Group (corporate communications) Jan Taylor & Associates (community consu ltotion)

Gibson Island AWTP MWH Worley Parsons Baulderstone Hornibrook United Group Infrastructure

Eastern Pipeline Alliance

AJ Lucas Transfield Services GHD Sunwater

Bundamba AWTP Thiess Black & Veatch

Western Pipeline Alliance McConnell Dowell Abigroup GHD

Luggage Point AWTP CH2MHill Laing O'Rourke Connell Wagner

Figure 3. Stage 1A Media Event (July 2007).

Hatch

Journal of the Australian Water Association

Water

JUNE 2008 67


technical features

GRP pipe installed in the western part of the project (Figure 2). This is the first major application of this particular GRP technology for an Australian pipeline project.

management framework in relation to water qualiry. This is discussed in more detail in Part 3 (Roux et al, 2008). Water Release to Wivenhoe Dam

Delivery Status

There are few examples of planned indirect potable reuse of water worldwide. The WCRWP is understood to be the third-largest such scheme in the world. There are even fewer examples of indirect potable reuse schemes where the water is recycled via a surface water storage. In chis respect, the scale of the WCRWP is unique.

Stage l A of the project began water deliveries on 27 August 2007, amid significant press coverage (Figure 3) Up to mid-March 2008, approximately 2000ML of purified recycled water had been delivered to Swanbank Power Station. (Figure 4).

Stage 1B remains on schedule for comp letion by the There are several end of June 2008, the pipeline circumstances, however, where and pu mp stations from Figure 4. First water flowing to Swa nbank Power Station. Bundamba to Caboonbah wastewater effluent is delivered (about 80km) are complete, into water storages chat are used system has been demonstrated ro be and commissioning has commenced on for potable water. Examples include Lake effective in removing NDMA chat is present Stage 1B of the Bundamba Advanced Water Mead (Hoover Dam) in Nevada, USA, ahead of the process. Treatment Plane (Pare 2, O'Toole, 2008) where wastewater effluent from Las Vegas As can be expected, however, a fasttracked project of chis scale is not without its challenges. There are several cri cical paths and the respective alliances are working to very eight schedu les to ensure chat all of the works are delivered on time. The treatment plants at Luggage Point and Gibson Island, which form pare of Stage 2A, are well-progressed. (Figure 5). In both cases, commissioni ng is expected to commence in early June with completion (including one month of performance resting) on target for the end of October.

Recycled Water Management

With the completion of Stage 2A, the project will deliver purified recycled water to Wivenhoe Dam to supplement the region's water supplies. As might be expected, this has had considerable commun ity interest. W ithin Australia chis is u111que. In parallel with the development of the WCRWP, the Queensland Government has been developing a legislative and

discharges to the dam; and the Upper Occoquan system in Virginia, USA, which under some ci rcumstances forms a significant part of the water supply for Washington DC. Th is can be contrasted with the Newacer project in Singapore, where currently only abo ut 1% of the water is released to water storages for recycli ng, since most of the water is used for high-value industrial applicatio ns. The proportion of Newacer

Treatment Performance

To dare, performance of the Stage lA plant at Bundamba has met all of the cri tical water quality parameters. There have been some excursions in turbidity and chlorine levels, but these are largely due to issues with system control which are currently being addressed by the Alliance. As would be expected from a reverse osmosis plane, there has been zero detection of any micro-organisms in the produce water. All of the metals remain well below specification Typically, total nitrogen has been around 0.5mg/L, about half the long-term target, and total phosphorus has been around 0.0lmg/L (or lower, with results at the limit of reporting). Phosophorus levels will presumably decrease further when the pretreatment coagulation system is commissioned. NDMA has remained at 5ng/L, the limit of reporting. The advanced oxidation

68

JUNE 2008

Water

Figure 5. Gibson Island AWTP Progress (Feb 2008).

Journal of the Australian Water Association


technical features

released co rhe storages will increase, however, as rhe scheme's capacity expands with the construction of rhe new Changi facility. WCRW Pry Ltd is funding on-going monitoring of water quality in Wivenhoe Dam by SEQ Water. This includes sign ifican tly enhanced monitoring of water quality, and a range of primary research acttvmes.

Concentrate Management One of the less publicised, yet signifi cant, benefits of rhe WCRWP is a reduction in nutrient release ro the Brisbane River and Moreton Bay. Phosophorus is primarily removed through coagul ation at rhe srarr of rhe treatment process. Ir is anticipated that up to 90% of the total phosphorus load th at would otherwise be released from the six wastewater treatment plants could be removed in this way. There are tradeoffs with chem ical use, however, and rhe likely production regime will reduce total phosphorus by around 50%. There will also be a significant reduction in rhe mass load of nitrogen. Indicatively, half of the nitrogen will be removed. This will be achieved through treatmen t of rhe reverse osmosis concentrate (ROC),

although some other options remain under consideration. Ar Bundamba, for example, rhe ROC is passed through nitrifying and denirrifying filters to manage ammonia (primarily arising from chloramine dosing ahead of the membranes) and nitrates, respectively. Ar Luggage Point, denitrificarion is also being co nsidered although a wetland trial is being co nducted as an option rhar is potentially lower cost and which has rhe potential co provide additional habitat areas. In each case, the concentrate has been subject to eco-toxiciry resting and near-field hydrodynamic modelling to ensure that there are no localised acute impacts. Farfield modelling has demonstrated rhe broader performance of rhe system.

Conclusion The Western Corridor Recycled Water Project is one of the most significant water projects in Australia, and is the third-largest advanced water treatment project in rhe world. The project is progressing well, particularly given the short delivery rimeframes, and is on rarger fo r completion to a capacity of 232ML/d by che end of December 2008.

The project will deliver significant benefits to South East Queensland, including enhanced supply reliabi lity and environmental benefits through reductions in nutrient release co che region's waterways. Ir is a project of which all Australians can be proud, and something chat places Australia at the forefront of water recycling worldwide.

The Authors Warren Traves is Engineering Manager for rhe project and is with GH D Pry Ltd, Brisbane, email warren.traves@GHD. com.au. Keith Davies is the Chief Executive Officer for Western Corridor Recycled Water Pry Ltd, Brisbane, keirh.davies@westerncorridor.com.au

Further Papers This paper is based on presen tarion #58 to Enviro08, followed by: • O'Toole G. Parr 2, this issue. Based on presentation #59 to Enviro 08. • Roux, A et al Part 3, this issue. Based on presentation #60 to Enviro 08. • Howick R Parr 4, chis issue. Based on presentation #44 to Enviro 08. • Plus: Berry, C. Water 35 No 2, March 2008. pp 121-124 (The pipelines) .

~ (7'PUMPS


technical features

PART 2. THE BUNDAMBA ADVANCED WATER TREATMENT PLANT: DESIGN, CONSTRUCTION AND START-UP G O'Toole, J Bates, R Dagwell, G Hattie Introduction The Bundamba AWT Plane will treat wastewater from four wastewater treatment plants at Bundamba, Goodna, Waco! and Oxley for use in two power plants and also indirect potable re-use, as outlined in the previous paper by Traves et al. The power plant operators requested char the quality of the recycled water be no worse than the current quality of stored reservoir water. Principally this means the total dissolved solids, nitrogen and phosphorus levels in the secondary wastewater treatment plant output need to be lowered significantly. Also, as the recycled water may be used for irrigation and reservoir recharge, nutrient levels must not add to the background nutrient levels measured in the reservoirs . Concerns about emergi ng contam inants must also be add ressed to allow indirect potable reuse. Bu ndamba Stage lA has a capacity of20 Ml/d and has been delivered fast-track in order to allow operations to commence in September 2007. Bundamba Stage 1B was completed and commissioned in April, increasing capacity to up to 66 MIid.

Development of the Treatment System In early 2006 a ream of Black & Veatch and partners GHD and Sun Water were ap pointed to a consultancy role by the Q ueensland Government to carry out preliminary d esign for the overall WCRW Project, which comprises the AWT planes, as well as the distribution network and major pumping stations. Review of an existing business case co nfirmed the general viabili ty o f the project. The o riginal treatment strategy, however, was nor optimised, with wastewater from the various wastewater treatment plan ts The Bundamba Project achieved an Honor Category in the Project Innovation Awards of the Internacional Water Association, Ease Asia and Pacific Region , and wi ll compete in September against finalists fro m ocher World Regions.

70 JUNE 2008 Water

Figure l. Aerial View of Bundamba AWT Plant - September 2007.

(WWTPs) being treated up to three times prior to discharge to the environment. Ir had been proposed char wastewater from Luggage Point WWTP be treated prior to being mixed with wastewater from G ibson Island, Oxley, Waco], Goodna and Bundamba WWT Ps. The entire flow was then proposed to be treated once again at Bundamba AWT Plant. Crucially the consultancy team came up with an optimised treatment strategy, requiring one time treatment at the WWTPs which resulted in significant p roject savings. The overall treatment strategy, as well as rhe schematic treatment processes at Bundamba A WT Plant, has been summarised in the p revious paper. In rhis design, treated water can either be used locally in areas around each of the AWT Plants, at potential sites along rhe length of each transfer pipeline, or can be readily combined at Bundamba AWT Plant

High technology delivered fast-track.

Journal of the Australian Water Association

for transfer along the western corridor. This transfer offers a range of uses, including power station cooling, irrigation or industrial applications, or to storage at Lake Wivenhoe for indirect potable reuse.

Fast Tracking the Delivery of Bundamba AWT Plant Due to the need to ensure that the project was started as early as possible, in June 2006 the EPC (engineer, procure, construct) joint venture of Black & Veatch/Thiess Construction fo rmed an Alliance with the government, known as the Bundamba AWT Plane Alliance, and rook responsibility for designing and constructing in stages the Bu ndamba AWT Plant. The contract was awarded with a co mpletion dare of the 3rd q uarter of 2007. In order to meet this demanding schedule, the project ream had to design the plant to allow construction and start up in a very short period. The basic treatment process and major operating parameters had already been established during rhe concepmal design stage. However, major equipment


Table 1. Principal Design Raw W ater Quality Parameters. At Stage 1A Parameter

Suspended Solids Turbidity, NTU Biolog ical Oxygen Demand (BOD) Total Organic Corbon (TOC) Temperature °C (min-max) Total Dissolved Solids (TDS) ## Total N (as N) Ammonia (as N) Total Phosphorus (os P) Manganese (Mn) Alkalini ty (os CaCO3)

Bundamba

Goodna

Waco!

Oxley

Typical

Max

Typical

Max

Typical

Max

Typical

Max

2. 3 2 11 25 500 4.7 0.9 1.9 0.04 140

10 10 40 10-30 1200 10 3.6 9 0.08 240

3.8 2.7 12 25 490 3.3 2.2 6.9 0.046 140

33 12 35 10-30 720 26.4 13.7 12.4 0.068 240

2.5 3.1 3 25 490 7.7 0.58 8.8 0.02 138

20 14 12

16 7 5.0

62 * 12 25

had to be selected based no r only on lowest whole of life cost bur also on consrructabil iry. W ith these criteria in mind, the Bu ndamba AWT Alliance appraised and selected equ ipment that would minimise excavation and shorten construction rime as well as maximising off-sire erection and resting. Th is resulted inter alia in the selection of encased skid-mounted pretreatment and RO membranes and in-pipe UY equipment. Earthworks were min imised and major tankage was designed to be entirely above ground to maximise pre-casti ng. By September 2007, the plant was completed, as shown in rhe aerial photograph, Figure 1.

Process Considerations

At Stage 18

been difficult to esti mate because nutrient removal facilities have nor been is service long enough for meani ngful perfo rman ce data co be available. Ar Stage IA rhe wastewater is supplied by Bundamba and Goodn a WWTPs and nitrogen and phosphorus removal measures will on ly be pu t in place at Stage 1B. The main treatment steps of ulrraftlrrarion (UF) membranes, reverse osmosis (RO) membranes followed by advanced oxidatio n using UV irradiation and hydrogen peroxide, together represent rhe gold standard for water reclamation. Bundamba AWT Plant is the fast fu ll-scale facility designed to meet such stringent nitrogen, d isinfection and emerging contami nant quality parameters.

-

-

-

10-30 720 16 9.4 14 0.05 190

25 660 8

10-30 780 15

6.9 0. 1 140

18 0.5 240

T he treatment steps are as follows: • Flow Balancing; • Chloraminarion; • pH adjustment; • Micro-straining; • Pre-treatment before membrane ft ltrarion; • UItra-ftlrration (U F) • Reverse O smosis (RO) Desalting; • Hydrogen Peroxide+ UV; • Stabilisation; • Treated W ater Storage; • Pumping to Distribution The principal quality parameters of rhe various infl uents are shown in Table 1.

T he prin cipal treated water quality A major consideration in the overall design requirements parameters are of Bundamba AWT Plant is shown in Table 2. rhe need at Stage 1B co rrear a Table 2. Principal Treated Water Quali ty Objectives. blend of wastewaters from Technologies fo ur oudying WWTPs, each Parameter Concentration Preliminary Treatment with different treatment comprises chlorami narion, Nutrients processes and configurations coagulation and pH and different secondary Total Nitrogen during Performance Trials 0.8 mg/ I adjustment. wastewater quality. As an Total Nitrogen during the subsequent 5 years 1.2 mg/ I example, Bun damba WWTP A chloramine residual of l Total Phosphorus 0. 13 mg/ I provides full biological mg/I minimises bio- fo uling of Minerals nitrogen and phosphorus rhe UF membranes. The Hardness as CaCO3 >50 mg/ I removal so the wastewater ammonia co ncentration in the >40 mg/ I Alkalinity contains less rhan Smg/1 of wastewater from the various Corrosiveness coral nitrogen and less than WWTPs is not co nsistent and Calcium Carbonate Precipitation Potential (CCPP) 0 to-5 2mg/ l of coral phospho rus. ti ne rn ning is required, so Total O rganic Carbon 1 mg/ I On the ocher hand Goodna ammonia needs co be dosed as and Waco! WWTPs do nor Nitrosodimethylamine (NDMA) 10 ng/ 1 well as chlorine. include phosphorus removal. Endocrine Disrupter Compounds Ferric chloride is added co O xley WWTP has been Estrone 3 ng/ 1 assist flocculatio n and allow developed in stages and only 17-beta estradiol (E2) 1 ng/ 1 materials to be removed by rhe the recendy added extensions Ethinylestradiol (EE2) 0.1 ng/ 1 ultra-filtration membranes include phosphorus removal. Tota l PNEC 1 ng/ 1 before they reach the RO Also, phosphorus 7 ng/ 1 Nonlyphenol (NP) membranes. concentrations at Oxley have Journal of the Australian Water Association

Water

JUNE 2008 71


technical features

pH is controlled co remove phosphates to minimise RO fou ling.

and less piping - all resulcing in less maintenance and lower plane footprint. Readily available RO module diameters for large planes can be either 16" (various) or 18" (Koch). The Bundamba AWT Plant will contrib ute to this industry debate with study of its monitoring and maintenance program.

Advanced treatment - comprises

micro-straining, UF membrane filcracion, Reverse Osmosis desalting, advanced oxidarion (UV + H2O2) and stabilisation. Micro-straining

Two (ducy/scandby) 500 ~1m duplex self-cleaning basket strainers from Amiad Filtration remove the majority of particulate matter and protect the downstream ulcrafilcracion membranes. Strainers are backwashed on a pre-sec differential pressure.

The RO system comprises skids housing 3-scages of membranes arranged in 7:4:2 array. Each skid is nominally rated co produce 7.5 MIid of permeate. Membranes have been selected primarily to Figure 2. Memcor encased p re-treatment membranes. reject nitrogen. The created water quality cargec for nitrogen is 1.2 mg at the end of five year's allow chis approach to be taken and as a Pre-treatment membranes operation, which has been specified so as result the consultancy team limited Although generically referred co as micronor to add co the nitrogen levels in rhe allowable nominal membrane flux to 44 filtration membranes ar Bundamba A WT receiving water in Lake Wivenhoe. On the licres/m 2 of membrane area/hr (lm h). Plane, encased Ulcra-filcration (UF) basis of competitive tendering and a There are several examples of projects membranes from Siemens (Memcor) performance specification, Koch's HR where higher fluxes have been shown co be (Figure 2) remove remaining particulate (high rejection) membranes were chosen sustain able. However, rhe need to 'gee it matter, while dissolved matter passes for this project. Nitrate reduction is right first time' rook precedence in chis through . Membrane differential pressure targeted at about 85% along with ammonia aspect of the process design. It should also (trans-membrane pressu re - TMP) and flux rejection of about 90%. be noted chat higher fl ux generally means (flow per unit area of membrane) is higher pumping head and hence operating Advanced oxidation generally maintained by regular (every 30 cost - so while rhe effect of limiting flux mins) air scour 'backwashes'. Nevertheless, While advanced oxidation is not required may be co increase CAPEX, minimising TMP trends upwards over rime (normally co meet rhe water quality requirements for to an improved whole-ofOPEX can lead about 30 - 35 days) until a nominal limit the power planes ar Swanbank and Tarong, !ife costing. Overall system recovery is not of 1.5 Bar is reached - because of attached iris required in order for rhe reclaimed less than 90%. particulates and biological fou li ng. The water to be discharged to Lake Wivenhoe, membrane then requires chemical clean-inReverse osmosis (RO) desalting The water must con tain minimal levels of place (CIP) to reduce TMP and control pathogens and trace organics and be Koch 18" diameter RO membranes are pumping coses and co ensure throughput is protected against emerging contaminants. used to remove che dissolved polluranrs maintained. CIP uses solutions of sodium (Figure 3) . With chis in mind, dosing of hydrogen hypochlorite and/or citric acid sequentially. peroxide and exposure to ultraviolet light For large plants, the RO membrane Pre-treatment membranes are guaranteed in -pipe is adopted co meet rhe California is currenrly tending cowards large industry co operate fo r a 5 year period co provide Department of Health Services guidelines diameter membranes for reasons char filtrate having che following quality for water recycled to a drinking water apparently include lower capital cost, fewer parameters: source (a I-log reduction in Nmembranes required for rhe same â&#x20AC;˘ Sile Density Index (SDI) no greater than nicrosodimechylamine or NDMA an d a throughput as well as fewer co ntrol valves 4 (100% ile) and 3 (90%i le); 0.5-log reduction of 1,4 dioxane). â&#x20AC;˘ T urbidiry 0.1 NTU (95%ile) The UV equip ment is of che and 0.2 NT U (I00o/oile) medium pressure type provided by The normal approach co determining operating parameters for full scale pre-crearmenr membranes is to undertake a comprehensive pilot resting programme, usually involving a selection of com mercially available membrane systems (immersed and encased). Typically such pilot testing, in order to be meaningful, should last for nor less than six months. This normally captures two Cl P cycles and establishes optim al backwash and cleaning regimes. However, the urgency of rhe Bundamba project did nor 72 JUNE 2008

Water

Trojan Technologies. Design UV transmittance at 253.7 nm is 95%. Applied UV dose is about 1200 mJ/cm 2 . Stabilisation

11

Figure 3. Koch 18 Di a meter High Rejection RO Membranes.

Journal of the Australian Water Association

Calcium Carbonate Precipitation Potential (CCPP) is the metric used to determine rhe aggressiveness of the created water. RO permeate is very aggressive as it is low on minerals and left unchecked chis would over time cause corrosion of downstream infrascruccure. Ac Bundamba AWT Plant lime and carbon dioxide are dosed in-pipe ro


technical features

maintain CCPP in the specified range of O to +0.5 (90%ile) and chis is sufficient co protect the downstream distribution network. Waste Treatment RO concentrate

Pre-treatment membrane backwash and RO concentrate are seeded in separate gravity thickeners. UF membrane backwash supernatant is returned co the Raw Water Tank for treatment.

Sludges are collected in a Waste T ank fro m where (at Stage lA) it is pumped to the Bundamba Figure 4 . September 2007 - Queensland 's Pol itica l WWTP fo r treatment. At Stage Leaders ra ise a toast to the Proiect - drinking recycled l B, due to limitation on the water with Gus Atmeh of Thiess. capacity of the Bundamba WWTP, a dedicated Sludge In order chat the instantaneous necessary because of concerns about si ngle Dewacering Facility has been provided to nutrient and suspended solids loads in the point nutrient discharge and the likelihood dewater sl udges to cake having a dry solids Bremer and Brisba ne rivers do not exceed of exceeding instantaneous nutrient loading concentration of 15 - 20% (w/v). Cake will limits imposed by the Environmental in the rivers - even though che total be transported to landfil l. Protection Agency (EPA), biological nutrient loading will hardly be affected. treatment of RO concentrate (or reject) is The RO concentrate treatment system Methodical Approach to Plant Start carried out to achieve the fo llowing co mprises lamella place settlers provided by Up nutrient and suspended solids limi ts on a IOI, followed by deep bed de-nitrification 50%ile basis: Given the ambitious project sched ule, a fil ters provided by Severn T rent. methodical 'stare-up' approach to managing nitrate as N - I mg/I Other wastes the comm issioning and setting to work phosphorus (as P - 4 mg/I Ocher wastes generated by the treatment process was essential. Black & Veatch Toca! Suspended Solids - 10 mg/I process are OF membrane backwash and consider the process and activities involved It is unusual to treat RO co ncentrate to sludge from RO concentrate lamella in starring up water or wastewater plants or ch is degree bur the EPA has deemed it thickeners. power stations involve the same methodi cal T he dissolved matter captured by RO membranes is rejected in concentrated form. Typical levels of nutrients and solids are nitrate - 27 mg/I, phosphorus (as P) - 7 mg/I, TDS - 6,400 mg/I and T SS - 30 mg/I

Journal of the Australian Water Association

Water

JUNE 2008 73


technical features

procedures and that the same challenges need to be addressed. The objective of the acceptance testing and proving phase was to safely commission and transfer the packages, systems, and facil ities in a timely manner. This begins with planning and scheduling performed during the Detailed Design Phase and fin ishes when the testing and initial operation is complete and the facility is ready for acceptance by Veolia Water Australia. A derailed commissioning program was developed consisting of the followi ng items:

Project Timeline 1A EPC Job

Jan

F

M

L.....;._ ___:_----1---

Stage 1A Process Design Complete

Stage 1A Pricing Complete

A

- - --S';~ ---=====~=t------t-l --:

Consultancy Work Begins

Begins

Copcrete w9rk Begins

'

''' ''

r - - - -- - - - - - -- - - - - - - - - - - - - - - - - - - - - - - - - -- - - - - - - - - - - - - - - -- - - - - - - - -- - • - - - - • - - - - - - - - -- - - -

Substantial Completion

PO Awards'

• Scarr-up scheduling; Mech Piping Work Begins

• Turnover packages; • Start-up Process; • Scarr-up Manpower Plan;

Skids on Site

' MF, RO, UV Purchase Orders Issued in October 06

• Major Scarr-up Activity Planning; • Start-up Support Planning. Despite the face char the Scarr-up ream was primarily accustomed co scarring up majo r power generation facilities, the methodical scare up process proved itself. Process engineering support from Black & Veatch water specialises was a key element in rhe scare-up process as was early involvement of the Scarr-Up Manager with the Design Team.

Achieving a Fast Track Project Timeline Figure 5 shows the project rimeline. In order co meet the ambitious schedule it was necessary to rake fu ll advantage of the flexibility of rhe Alliance delivery approach by carrying out the followi ng activities before fi nalisation of the project carger cost: • Procuring long-lead items (membranes, pumps, skids, UV); • Commencing earthworks and foundation works. As a result detailed design was always nor far ahead of construction and the submission and accuracy of vendor derails was crucial. Derailed design had co be carried our around rhe clock and around the globe. A close working relationship between designers from Black & Veatch, Parsons Brinkerhoff and GHD helped enormously. Construction had to be well organised and right first rime. Thiess Construction proved themselves up co the cask. Despite rhe challenges of the project rimeline, throughout construction, commissioning and start-up, quality was maintain ed and safe worki ng procedures srricrly adhered co, with more than 1.6 74 JUNE 2008

water

Figure 5. Project Timeline for Western Corridor Scheme Conceptual Design & Bundamba AWT Plant Stage l A.

million man-hours worked without reportable incident as of the rime of writing.

Commissioning Challenges: Lack of Wastewater Ironically one consequence of water scarcity, which is rhe very rationale for the WCRW Project, was obtaining sufficient wastewater co commiss ion the AWT Plane. Level 6 water restrictions in Brisbane and South Ease Queensland, while effectively reducing consumption, also resulred in less wastewate r arriving at the WWTPs. So a Catch 22 situatio n arose where rhe AWTP is nor able co operate at full capacity unless and until water restriction ease - resulting in more wastewater.

Preliminary Operating Data Verify Design Stage lA, at che time of writing has been in service for nine months and has demonstrated performance in accordance with rhe created water quality objectives given in Table 2. Stage lB has been completed and co mmissioned, and initial data shows similar performance co Stage lA.

Current Project Status Scage lA of rhe Bundamba AWT Plane is complete and was handed over co the scheme operator, Veolia Water Australia during March 2008. Thus far created water quality meets rhe project objectives. See Figure 4.

Journal of the Australian Water Association

Stage 1B of the plant was completed and commissioned in April 2008.

Conclusions The early stage of rhe WCWR project has demonstrated that relieving the pressure on tradi tional stored water resources by substituting recycled wastewater for major industrial users is entirely practical. In severe water stressed areas of the world, rhe application of membranes in combi nation with advanced oxidation treatment processes allows recycled water safely to be stored and mixed with catch ment run-off fo r indirect potable reuse (IPR). The WCRW Project is a far-sighted and innovative project, which will help secure the water needs of the residents of Queensland and which will serve as the yardstick for the success of sim ilar schemes worldwide. The Bundamba AWT Plane applies rrearmenr processes which represent the gold standard for water reclamation. The quality of the recycled water meets the project objectives, which have been sec against the highest industry standards. Major water infrastructure can be delivered to high quality and to a fast crack schedule provided the right mindset in all parries exists fro m the outset.

The Authors Gerry 0'Toole (email OTooleg@bv.com), Jon Bates, Richard Dagwell and Gary Hattie are all with Black & Veatch Water Asia Pacific.


PART 3. WATER QUALITY MONITORING AND RISK MANAGEMENT A Roux, M Pirrone, B Bowen, T Walker Abstract A recycled water managemen t plan has been developed to control water quality in the Advanced Water T reatment and transport system of rhe Western Corridor Recycled Water Project. This plan fo llows rhe risk management approach ourlined in rhe Australian Guideli nes for Water Recycling. Water quality hazards were assessed and critical control points determined. Source water quality was characterised through a sou rce water characterisation program and from chis a purified recycled water verification monitoring program was developed.

Introduction T he W CRW Project is the first project in Queensland with rhe porenrial to supplement urban drinking water supplies with purified recycled water. The sporlight is on the project so significant attention is being paid co managing risk, and to ensuring char all rhe parries associated wirh the production and transport of purified recycled water are involved in rhe process of ma naging and co ntrolling risk.

Recycled Water Management Plans T he Queensland Department of Natural Resources and Water (NRW) is developing a Recycled Water Regulation under the new Water Supply (Safety and Reliability) Act. Th is regulation will require any enti ty supplying or using purified recycled water ro submit a recycled water management plan ro NRW fo r approval. Mose of the prin ciples in the Australian Guidelines for Water Recycling (Phases 1 and 2) will apply ro rhe approval of recycled water management plans. The Department of lnfrasrrucrure and Planning is rhe Queensland Government department responsible for rhe Western Co rridor Recycled Water Project. !rs responsibilities include coordinating rhe development of an overall recycled water management plan fo r rhe project and submitting chis plan ro NRW .

Table 1. Entity responsib ilities Section of Scheme

Responsible Entity

Domestic a nd industrial wastewater catchments

Ipswich and Brisbone City Councils

Wastewater treotment

Ipswich a nd Brisbone City Councils

Advanced water treotment a nd transportation

WCRW Pty Ltd (through operating contract with Veolia Water Australia)

Industrial use of purified recycled water

CS Energy and To rong Energy

Storage and blending of purified recycled water with other sources in dams

SEQ Woter

Treatment of water from dams to drinking water quality standards

SEQ Water

Under the proposed new regulation, however, each of the entities controlling supply or use of water from or ro any section of the WCRW Project muse also prepare a recycled water management plane to address risk in its segment of the purified recycled water supply chain. T he overarching recycled water management plan wi ll be supported and refe r to rhese enciry pl ans. Western Corridor Recycled Water Pry Led (WCRW Pry Led) is rhe wholly Queensland Government owned co mpany responsible fo r deli vering the W CRW Project. The company will own the advanced water creacmenr planes and pipelines and is responsible fo r submitting a recycled water management plan. Veolia Water Australia has an operations and maintenance agreement with rhe company and will be responsible for implementing the key elements of rhe plan. T he plan will be an extension of Veolia's standardised lnregrared Business Management System.

Multiple barriers to manage risk A risk-manage ment app roach requires char risk be controlled as close as poss ible ro the source of rhe hazard, and char multiple barriers be implemented. There are seven barriers in rhe purified recycled water process cycle. Four barriers

Ensuring a robust system is developed to minimise risk.

withi n the current water supply chain, i.e. res idenrial/industri al source control, wastewater rrearmenr planes, the management of fres h water storages and water rrearmenr, are all under outside con trol. T hree addition al barriers are introduced with rhe advanced water rreacmenr planes. Table I shows the entities responsible for the different elements of rhe water supply chain. Each entity muse develop irs own recycled water management plan. WCRW Pry Lrd has developed conrraccual agreements with upstream wastewater providers and downstream purified recycled water users.

Hazard Assessment and Critical Control Points A team representing each enti ty in the overall process identified hazards and assessed risks at the critical barriers fo r which ir had responsib ili ty and developed critical limits and monitoring strategies. Veolia Water Australia then conducted an ope rational hazard assessment fo r the advanced water treatment section of the scheme.

Assessing hazards T he Veolia risk management procedure, which describes a semi-quantitative process raring likelihood and co nsequence our of five, was used ro assess water quality hazards. Water quality hazards were grouped according to type of hazard (physical,

Journal of the Australian Water Association

Water

JUNE 2008 75


technical features

chemical, biological, radiological) and its potential impact (human health, environmental or infrastructure) and correlated with the heal th hazards identified in the overarching Recycled Water Management plan. Water quantity hazards co uld result from a shut-down due to the presence of contaminanrs in water. Assessing Likelihood: T he extent to which a barrier would control a hazard was assessed to determine likelihood and the monitoring process to detect failure of the process was determined. Assessing consequence: Any failure to meet guideline concentrations fo r any human health hazard was considered to be of equal health co nsequence. In assessing other consequences, Veolia's risk management procedure were used to determine commercial, legal and public perception impacts.

Table 2. Critical and Quality Control/Operational Points. No

Control Point

Monitoring

CCP l

Shut down of raw water pump station

Online turbidity, nitrate, ommonia, TOC and phosphorus

QOP2

Raw water pumpstation

WWTP influent flow (to detect bypass event), external laboratory analyses

COP3

Ch loramination

Online chloramine, ammonia ORP

COP4

Coagulation dosing on MF feed

Online phosphorus analyser

CCP5

Microfiltration

Direct integrity testing

COP6

pH high RO feed

Online pH analyser

COP7

Antiscolant dosing

Antiscalant flow rate

QOPB

Metal ions in reverse osmosis feed

Onsite analyses

CCP9

Reverse osmosis

Online conductivity on combined permeate from eoch train.

CCP l 0

Advanced oxidation process

Power ratio, Hydrogen peroxide flow rate.

COPl l

Stability dosing

Online pH, conductivity analysers

CCP12

Final chlorination

Online free and total chlorine analysers prior to treated water tank

QCP13

Purified recycled water quality at pump station

Online chlorine, turbid ity, conductivity and pH analysers and external analyses. External analyses of indicator organisms

QCP14

Distribution system

Critical points

QOP 15

Microfiltration backwash clarifier

Onli ne turbidity analyser

After che hazards were assessed, each step in the advanced water treatment process was evaluated and treatment barriers matched with the hazards th ey controlled.

COP16

Reverse osmosis concentrate (ROC) breakpoint chlorination

Online chlorine and ammonia analysers

COP17

ROC dechlorination

Online free chlorine analyser

COP18

ROC pH correction and PO4 coagulation Online pH and phosphorus analysers

Cri tical points - points where water quality can be controlled and which are essential to prevent a hazard or to reduce it to an acceptable level - were identi fied. Quality points - process steps that, while important, cannot be monitored online or are not under the direct co ntrol of the operator of the treatment process - were also identified. Two distinct types of critical points were idenrified. Critical points controlling health hazards were idenrified as critical control points (CCPs) and those controlling water quantity hazards were identified as critical operational points (COPs) . Quality points were similarly distinguished as Quality Control and Quality Operational Points (QCPs and QOPs). Veolia will manage all critical and quality points with the same amount of rigour and within the same operational plan because supply continuity, environmental compliance, and water quality are all important to ensure a sustainable water supply. However, only CCP/QCPs will be recorded in the WCRW recycled water management plan and its reporting requirements apply only to CCP/ QCPs. To identify CCPs, a decision tree was used with the overlay of che following principles: • CCPs are seeps where consequences of failure are irreversible (United States Environmental Protection Agency [USEPA]); 76 JUNE 2008

Water

QOP19

ROC denitrification

External laboratory analyses

QOP20

Trode waste quality

Online pH and conductivity analysers

COP21

CIP waste tank

Online pH analyser

• CCPs are steps at which conrrol can be applied and are essential to prevent or eliminate a safety hazard or reduce it to an acceptable level (Wo rld Health Organization [WHO]); • Does the step act specifically on the process or the product in order co avoid or reduce the risk to an acceptable level? At this step, is there a con tinuous monicoring allowing immediate action co return co normal operation or prevent water being distributed? (VW presentation);

• If a subsequent step would control the hazard but it was desirable co have additional control co provide a higher level (log removal) of protection, rhe barrier may still be considered a CCP. Table 2 summarises the CCP/COPs chat were identified. Validation

Validation of efficiency of barriers for treatment of water qual ity hazards may include the following: 1. Manufacturers' guarantees and evidence of challenge testing.

2. Confirmation that manufacturers' design operating conditions can be maintained through commissioning.

Journal of the Australian Water Association

3. Performance sraciscics from peerreviewed published information and hiscorical data 4. Monitoring of surrogate parameters to prove removal efficiency during performance resting (indirect integrity monicoring). 5. Accreditation of process efficiency provided by reputable international agencies (such as the USEPA) for the specific type and model of equipment installed. 6. Mo nicoring of process settings duri ng perfo rmance tests and proving periods co demonstrate process is designed according co USEPA accredited process or manufacturers' specification. 7. Intensive monico ring of target parameters during perfo rmance test and proving periods (referred co as the verification test) co demonstrate drinking water compliance. Verification Monitoring

A monicoring program is required to veri fy compliance with the Australian drinking water and water recycling guidelines. Source water characterisation

Element two of the risk management approach in the water recycling guidelines


technical features

requires an assessment of the quality of source water to be added to a drinking water scheme. A source water characterisation program was cond ucted between March and July 2007 on the six supplies of created wastewater to provide information on compounds co include in a verification rest. Characterisation requires long-term moni toring through a variety of environmental condi tions, which was nor possible in the cimeframe. Long term verification programs will be continuously updated as more in format ion about potential hazards beco mes available. This information wi ll be augmented with ongoi ng source water analyses and source water catchment risk assess men ts. Source characterisation was done using a variety of analytical screens (Queensland Health Forensic and Scientific Services (QH FSS), inorganic analyses and gross organic fractions (Scientific and Analytical Services - Brisbane City Council). Ac lease some compounds from each category in Table 4.4 in the Australian Guidel ines for Water Recycling 2 (2007) were included in the analytical screening. All standards collected from various areas in the Q H FSS laboratories were included in the spectrometri c analytical screens (liquid chromatography mass spectro metry (LCMS) and gas chromatography mass spectrometry (GCMS)) even though guideline limits for all these compounds were not necessarily avai lable. By including all these standards it was hoped that a good selection of standards for produces used in the local area would be included in the screens. T he analysts could also report the detection of compounds identified by instrument databases even where no standards were injected. W hen compounds were detected in this way, standards for chem were obtained to allow chem to be quantified. An example is galaxolide, which was tentatively identified during GCMS screens and fo r which a standard has being obtained for quantification on future purified recycled water and treated wastewater samples. Where it was known that compounds commonly form breakdown products, tech niques for these produces were also included. For example glyphosate (a ubiquitous herbicide), which breaks down relatively quickly to its more stable breakdown produce, aminomerhylphosphonic acid (AMPA), as well as Arrazine breakdown produces, were included in the organic screens

metals, gross organic measurements (TOC, coral hydrocarbons etc), nutrients, other inorganics, radiological screens, mi cro organisms, VOCs and THMs - (61 compo unds), haloaceric acids (6 compounds), nirrosamines (5 compounds), semi-volatile organics using GCMS and LCMS (145 pesticide/herbicide and 54 pharmaceuticals), phenoxyacid herbicides (14 compounds), glyphosare and AMPA, target PAHs and phenols (3 1 compounds), endocrine disrupting chemicals (12 compounds), and EDTA. Nicholson (2007) listed 20 pharmaceuticals most commo nly used in Austral ia for 1998. Of these, nine were included in the 54 pharmaceutical standards used in the WCRW Project source water characterisation.

in chis study as well as 11 of the 17 pharmaceuticals identified in the Snyder, Wert and Lei (2007) paper were included in the WCRWP Source Characte risation. Snyder, Wert and Lei (2007) used a 200 2 US-based study on organic contami nants found in "susceptible" surface waters to select target co mpoun ds to study the removal of endocrine disrupting compounds and pharmaceuticals th rough water treatment processes. The A ustralian Guidelines for Water Recycling (phase 2) provides a similar reference of compounds co be found in Australian wascewacers. Results and recommendations

Rodiguez et al (2007) selected 271 co mpounds from si milar groupings (VOCs, disinfection byproducts, metals, pesticides, hormones and pharmaceuticals) to rest a screening health risk assessment methodology on treated wastewater. Seven of the voes 12 of the pharmaceuticals and the same disi nfect ion byproducts detected

Gross beta activity in treated wastewater from one of che wastewater treatment plants exceeded the screening level defined in the Australian Drinki ng Water Guideline. Preliminary dose assessment revealed char the guidel ine limi t is nor likely co be exceeded. Regardless, gross beta acti vity would be incl uded in ver ification monitoring. Mose compounds fro m che pharm aceutical , herbici de and pesticides groups char were detected appeared to be

Save Water and Reduce Filter Maintenance MULT1 (}vcLONE • Centrifugal water filtration • No filter media to clean or replace • No moving parts • 3m 3/hr to 30m 3/hr • Easily manifolded for higher flow rates MultiCyclone is a pre-filtration device that Is capable of saving water and reducing filter maintenance. The MultiCyclone works on the basis of centrifugal water filtration. Incoming water enters its 16 hydro cyclones tangentially, generating a strong centrifugal effect. Incoming sediment is spun out to the hydro cyclone's wall and then spirals down to the sediment sump, while the cleansed water spirals upwards. Only 15 litres of water is discharged to clean the MultiCyclone.

NSW (Head Office)

OLD

VlC/TAS

02 9898 8686

07 3299 9900

03 9764 1211

SA / NT

WA

08 8244 6000 08 9273 1900

The list of analytical screens performed on created wastewater included heavy Journal of the Australian Water Association

Water

JUNE 2008 77


technical features

water soluble and liquid chromatography mass spectrometry (LCMS) was found ro be effective in d etecting these compounds. The glyphosare metabolite AMPA (aminomerhylphosphonic acid) was detected with reasonable frequency and will also be included in purified recycled water monitoring. Trichlorophenol was detected reasonably frequently bur at concentrations below the ADWG h ealth limits. Ir may be a useful indicator for removal of similar compounds. T rihalomerhanes (TH Ms) and NDMA were nor detected in significant quantities in the treated wastewater, except where samples were collected after wastewater chlorination (e.g. at Bundamba WWTP). THMs and NDMA could form in one of several chlorination steps within the advanced water treatment process and should form part of a purified recycled water monitoring program. Some compounds from the endocrine d isruptor compounds (EDC) group were frequently detected in rhe treated wastewater. These compounds (bisphenol A and nonylphenol) do nor have high endocrine activity and was detected well below rhe guideline limit. They could be indicators to track removal of compounds from this class. EDTA was detected frequen tly and at levels close ro rhe guideline values published in Table 4.4 in rhe Australian Guidelines for Water Recycling Phase 2. EDTA is a commonly used product in many industries and o ccurs in detectable concentrations, so ir will be a useful indicator compound. Very low levels (coral TEQ and two orders of magn itude less than the guideline value of 16 pg/L) o f polych lorinared biphenyls were detected in all treated wastewater rested. No d ioxi ns, pesticides from the pyrereniod and carbamare groups, organophosphare pesticides or halo acetic acids were d etected in any of the treated wastewater. Most of these co mpounds rend to b e far-soluble or attach themselves ro solids and, if present in the catchment, are expected to be well removed in wastewater treatment plants. The source water characterisation program provided additional information on the concentration of nutrients and various inorganic parameters.

Conclusion D evelopi ng a risk management p lan for the overall Western Corridor Recycled Water scheme, and rhe Advanced Water Treatment Section in particular, is essential

78

JUNE 2008

Water

in obtaining regulatory approval ro supplement d ri nking water supplies in South East Queensland. Because this scheme is the first and largest of its kind in Australia, the Queensland regulator is focused on ensuring a robust system is developed to minimise risk. A recycled water management plan developed according to the Australian Guidelines for Water Recycling and p rinciples in the Aust ralian Drinking Water Guidelines has provided a plan that satisfies the regulatory requirements as they are being developed . T hrough developing control points and response procedures, it has also provided robust operatio nal response procedures which fir within the integrated business management system of the scheme operator, Veolia Water Australia. Development of a comprehensive recycled water monitoring program requires source water characterisatio n and verification monitoring. Due to the short rimeframe of the project, long-term monitoring and characterisation of the catchment was nor possible. H owever, due to compreh ensive organic screening of the treated wastewater, the most common hazardous compounds in rhe catchments could be identified. The compounds char were detected most commonly correspond to what is found elsewhere in wastewater carchmenrs. A purified recycled water monitoring program based around the analytical screens able to detect most of the compounds found in the source water study should provide a suitable starring point fo r verification monitoring. Wastewater catchment risk assessments have commenced and chis verification monitoring will be augmented from information gained through these programs.

Acknowledgment The assistance of Queensland H ealth and Queensland H ealth Scientific and Forensic Services in d eveloping rhe Source Water C haracterisation Program is gratefu lly acknowledged.

The Authors Annalie Roux (email Annalie.roux@ veoliawarer.com.au), Troy Walker and Ben Bowen are all with Veolia Water Australia, Brisbane, Mario Pirrone is the Manager Regulatory and Support Services for Western Corridor Recycled Water Pry Ltd.

Journal of the Australian Woter Association

References Linden, K.G. (2007) Veolia AOP Seminar Brisbane, Australia October 26, 2007 ADWG: Australian Drinking Water Guidelines (2004) AGWR 2: Australian Guidelines for water Recycling: Managing H ealth and Environmental Risks: Phase 2. Drewes, J.E. 2007 The Stare oflndirecr Potable Reuse in the United States. Queensland Water Commission/ Department of Natural Resources and Water, 24 July 2007, Brisbane. Snyder, S . A., Wert, E.C and Lei, H. (2007) Removal of EDC' s and Pharmaceuticals in Drinking and Reuse Treatment Processes. Awwa Research Foundation, IWA publishing, 2007 Rodriguez, C., Van Buynder, P., Devine, B., Cook, A. and Weinstein, P. A rhree-riered approach ro screening health risk assessment: extending the range of chemicals assessed in recycled water schemes . Snyder, S.A, Adham, S, Redding, A.M, Cannon, F.S., DeCarolis, J., Oppenheimer, J., Wert, E.C., Yoon, (2007) Role of membranes and activated carbon in the removal of endocrine disruprors and pharmaceuticals Desalination 202 (2007) 156-181 Kimura, K., Amy, G., Drewes, J.A., Heberer, T., Kim, T-U., Watanabe, Y. (2003) Rejection of organic micropollucanrs (disinfection by-products, endocrine disrupting compounds, and pharmaceutically active compounds) by NF/RO membranes journal ofMembrane Science 227 (2003) 113-1 21 Drewes, J.A., Bellona, C., Oedekoven, M ., Xu, P., Kim , T-U., and Amy, G. (2005) Rejection of Wastewater-Derived Micropolluranrs in H igh-Pressure Membrane Applications Leading Indirect Potable Reuse, Published onli ne 7 November 2005 in Wiley InterScience (www.interscience.wiley.com}. DOI 10.1002/ep. 101 IO APHA, AWWA, WERF (2004) Standard Met hods for the Examination of Water and Wastewater (21 ed) AWWA press. Miyashita, Y, Lee, J-Y., H yung, H , Park, S-H., Huang, C-H ., and Kim, J. (2007) Removal ofN-Nitrosamines by Nanofilrration and Reverse Osmosis, American Water Works Association Membrane T echnology Conference, 2007. USEPA (2002) 40 CFR Pares 9, 141, and 142 National Primary D rinking Water Regulations: Long Term I Enhanced Surface Water Treatment Rule; Final Rule USEPA (2007) Issue Paper: Hazard Analysis Critical Control Point (HACCP) Strategies for Distribution System Monitoring, Hazard Assessment and Control, January 19, 2007


technical features

PART 4. ADVANCED OXIDATION AT BUNDAMBA AWT R Howick, A Festger

The final stage of a gold standard purification train.

Introduction

Arou nd the world a number of Indirect Potable Reuse projects have been implemented or are in progress. UV-oxidation (an advanced oxidation process usi ng UV and hydrogen peroxide) is being utilised to destroy the trace amounts of organic contaminants such as pharmaceuticals, industrial contaminants (e.g. 1,4-dioxane) and nitrosamines (mai nly fo rmed during chlorine disinfection) which ca n pass through the RO membranes. Two photochemical processes occur Figure simultaneously within the UV system during treatment. T he first, UV-photolysis, is the process by which chem ical bonds are broken by the energy associated with UV light. The second, UV-

,

to form highly reactive hydroxyl radicals. Hydroxyl radicals rapidly oxidise organic contaminants. UV disinfection is accomplished as well.

Membranes remove many co ntaminants, both microbiological and chem ical. However, nitrosamines, so me pharmaceuticals 1. The 20 ML/d installation at Bu ndamba 1A. and other compounds pass through RO membranes wirh limited treatment. oxidation, involves the addition of For this and other reasons, hydrogen peroxide upstream of the UV UV-oxidation is required. UV-oxidation reactor which is then activated by UV light performs fo ur primary fu nctions:

Specialist Environmental Solutions Ecowise Environmental improves the management of our environment by delivering quality outcomes to our clients. Our expert staff provide environmental data, technology and consu lting services for clients across government and industry. Ecowise Environmental has experience in catchments, mining, industrial and urban applications. We use the latest advancements in technology to provide innovative, efficient and cost-effective solutions that add ress regulatory and operational objectives in diverse environments.

6 1~ 1Jl l~

Ph: 1300 32 69 47 I www.ecowise.com.au Consulting

l

l Analytical I GIS

Ecowise Environmental

Journal of the Australian Water Association

Water

JUNE 2008 79


technical features

1. Destruction of nirrosamines and other contaminants treated by UY-photolysis (UY alone)

2. Destruction of pharmaceuticals, personal care products, and industrial chemicals treated by UY-oxidation (UY+ hydrogen peroxide) 3. Microbial disinfection 4. Additional protection: a cost-effective, easy co understand add itional barrier that helps build public confidence in treated water. The UV-oxidation system also acrs as a barrier ro currently unknown or unmonitored contami nants. The Groundwater Replenishment (GWR) System at the Orange County Water District (OCWD, California, USA) is utilising UY-oxidation for these purposes, as are a number of other projects in North America and around the world. The OCWD GWR System, the West Basin Municipal Water District Water Recycling Facility (Cali fornia, USA), and the Water Replenishment District have completed the installation of membrane/UV-oxidation treatment systems and are currently augmenting local water sup plies by groundwater injection/infiltration. Full-scale resting of these facilities has been highly successful. For example, the TrojanUYP hox™ at the OCWD GWR System reduced NDMA, one of the betterknown and more toxic nirrosamines, by the design value of 1.2-log (from an influent concentration of I 50 pans per trillion (ppr) the NDMA was reduced ro less than 10 ppr). O ther rests confi rm that at the treatment levels required co remove NDMA, a variety of chemical compounds including various pharmaceuticals and pesticides, are red uced by 75% co 95% (Swaim 2006).

Figure 2. The TrojanUVPhox™ at Orange County Water District, Californ ia, USA.

The design parameters for rhe T rojanUVPhoxTM system installed at Bundamba are based on flow and water quality parameters as fo llows: • Design Flow Race: 60 MLD • UV Transmission at 254 nm: ::::95% • 1,4-D ioxane Treat ment Capability: 0.5log

The TrojanUYPhox™ is or will be providing similar treat ment at the four treatment facilities of the Western Corridor Water Recycling Projecc. These facilities, located in Brisbane, are the Bundamba !A and I B, G ibson Is land, and Luggage Point Advanced Water Purification Faci lities.

80 JUNE 2008

Water

• Cryptosporidium T reatment Capability: »4-log • Virus lnaccivacion Capacity: >4-log The UV Treat ment Train at Bundamba consists ofrwo (2) Trojan UVPhox™ Model D72AL75 UV Reacror Chambers with inlet on the side and outlet on the cop. The Chambers are piped in a rwo (2) level floor-mounted rower arrangement, with reactor flow in series. The UV Reactor Chamber inlets/outlets are directly coupled and are mounted co a structural steel support struccure. Figure 1 shows the 20 Ml/d system in operation at Bundamba IA. Figure 2 shows the first system installed at the G roundwater Recharge plant at Orange County, CA. Figure 3 shows the 100 ML/d installation at Gibson Island.

Applications in the WCWRP

The TrojanUVPhox™ (UV-Ph otolysis and UY-Oxidation) provides a solution wh ich uses a pressurised ulcraviolec (UV) light reactor that incorporates Trojan's low energy, high output, monochromatic UV lamps, along with a dose of several pans per million of hydrogen peroxide. When all systems are in operation the coral flow co be created by UY oxidation w ill be over 200 ML/d.

• NDMA Treatment Capabil ity: 1.0-log

The Authors Ron Howick is Manager Standard Produces Division of Aquatec-Maxcon; email ronh@aquatecmaxcon. com.au. Adam Festger is the Enviro nmental Contaminant Treatment Market Manager for T rojan UV, based in Tucson, AZ; email afesrger@rrojanuv.com

Reference Swaim, P. (2006) Innovative Approaches to Water

Purification Using UV-Oxidation. CD-ROM

Figure 3. The 100ML/d installation at Gibson Island.

Journal of the Australian Water Association

Proceedings of the Annual Conference of the American Water Works Association, San Antonio, TX.


technical features i

PRESSURE SEWERAGE: THE FLINDERS PROJECT S French Abstract This paper describes rhe pressure sewerage innovations rhar South East Water has incorporated into rhe Flinders sewerage project, built on earlier operational experiences with rhe Tooradin, Warneer and Cannons Creek pressure sewerage systems. Other innovations were required to meet rhe technical challenges for a lengthy transfer system over undulati ng topograp hy.

Introduction M elbourne water retailer South East Water installed Australia's first large scale pressure sewerage system in Tooradin in 200 l. This was soo n fo llowed by similar systems in Warneet (2003) and Cannon C reek (2004). Ar rhe rime pressu re sewerage technology was relatively new to the Australian wate r indusrry, so the design methodologies and key equipment were primarily sourced from overseas.

Installation of Pressure Sewer Pump Unit a nd decommissioning of the property septic tan k.

South East Water has recently adopted a pressure sewerage system fo r the coastal township of Flinders on rhe Mornington Peni nsula, Victoria. T his project built on earlier experience and adopted an innovative approach to overco me a number of technical challenges associated with rhe town's relative remoteness and undulating topography.

Pressure Sewer Systems A pressure sewerage system uses rhe pressu re from individual pump units to transport sewage to a treatment plan or to the nearest connecting sewer system. These syste ms are particularly suitable for rural or semi-rural co mmunities where onsi re treatment systems are insufficient to safely rrear sewage. Each property within the pressure sewerage system is provided with a small rank with a pump unit installed to which all th eir household sewage is diverted. The tank fills until a predetermined rank level is reached when the pump unit is activated to pu mp waste our of the property. The ranks

Innovations to meet technical challenges. Journal of the Australian Water Association

Water

JUNE 2008 81


technical features

pressure sewerage also have a relatively large emergency storage above normal operating levels. The main benefit of p ressure sewerage systems is being able co use small diameter polymer pressure mains in road reserves, constructed predominancly by directional drilling, with liccle regard for grade. This results in lower capital costs and a significant reduction in discurbance co the environmental and local community during the project delivery. A second benefit is an almost complete elimination of inflow and infiltration.

Experiences with Pressure Sewerage Systems Through the experience of installing and operating Australia's first pressure sewerage systems in Tooradin, Warneet and Cannons Creek a number of limitations had been identified. These limitations included:

• Customer involvement in system operation

If there is a fai lure of the pump unit an alarm built into a control box sounds on the property alerting the customer to the fail u re. The customer then contacts South East Water who will arrange for maintenance co be undertaken on the pump. Due co chis customer involvement it is necessary co educate customers and call centre staff in basic pressu re sewerage operatio ns. T his is further complicated by the many false alarms that can be triggered. Some of these false alarms can be attributed to d ifficulties with passing solids through the pump grinder (which eventu ally pass). Other false alarms have been caused by the triggering of the pump electrical protection devices during electricity supply issues. Due co the relatively high number of false alarms that have been experien ced call cen ere staff may ask some customers chat have experienced an alarm to call back if the pump is still alarming after 1-2 hours.

• Control of system pressures Progressive cavity pumps are well suited to pressure sewerage systems as they can produce a relatively constant flow over a large p ressure range (with a relatively flat pump curve typically between 0-60m head of pressure). Although the progressive cavity pumps used in pressure sewerage have a maximum raced pressure typically berween 45-60m, they can produce pressures over 160m for short periods during peak pressure events. Consequencly, main bursts have occurred when sectio ns of the pressure sewerage system have been shut down, e.g. when isolation valves have been closed during

82 JUNE 2008

Water

Installation of the Flinders pressure sewer pipe network system maintenance. Therefore, to isolate any part of the sewer system an operator must either shut off all the individual pumps and/or connect a canker truck to a flush ing point to allow a point of d ischarge for the isolated section. Due to the uncontrollable nature of the original pressure sewerage pumps, the entire system needed to be designed such chat the dynamic pressure seen by every pump in the system is less than the pump's rated p ressure. This requires the system pipe work to be oversized to reduce dynamic pressure losses. However, by over-sizing the pipe work the reduction in velocity can result in solids build-up and air entrapment within the system.

• Risk of relatively large sewer spills from main leaks All pressure pipe systems are prone to leaks, burst or damage by others. Pressure sewers are no different, and although to date So uth Ease Water has not had any major spills, the risk of sewer spills from pressure systems will always remain. Th is risk is magnified since p ressure sewerage systems are generally located in fairly remote townships, where it may cake maintenance crews up to 2 hours to attend any issue.

• Effect of high system peak flows on downstream infrastructure Pressure sewers have significancly reduced inflow and in filtration resulting in minimal peaks during wet weather. However, significant flows up to IO times average dry weather flows can be produced by pressure sewerage systems during system recovery events after long outages - such as are experienced after power outages or system maintenance - since customers will continue to create wastewater which raises the level in the collection rank above the pump "cut in"

Journal of the Australian Water Association

by directional

drilling .

level. When the system becomes operational a majority of the pumps within the system will attempt co discharge at the same time, causing relatively high flows. T herefore, all systems downstream of a p ressure sewerage system need to be designed to manage these peak flows.

• Mess associated with pump maintenance on customers' properties W ith all p ump units being located on customer properties all maintenance activities (including pump change over) begin on the customer's property. Generally when submersible pumps are removed from their tank they are covered with solids and fats and are also dripping sewage. This requires submersible pumps to be cleaned on the customer's property p rior to maintenance or packaged up dirty and taken off-site for cleaning and maintenance.

• The need for pump rotor/stator replacement every 10 years As with most modern technology, pressure sewerage technology is generally designed to run to failure. H owever, the rotor and stator in some pressure sewer pumps requi re replacement every 10 years.

Flinders Sewerage Project The Flinders Sewerage Project required a sewer system to service approximately 800 p roperties within the Flinders township located approximately 75km south of Melbourne on the Mornington Peninsula. A pressure sewer option was chosen for the township reticulation based o n lowest capital and net present cost, the high environmental values of the area and the benefits of minimising disturbance during construction. As a new local sewage treatment plant was not feas ible for this project, a sewer


technical features

pressure sewerage transfer system was also required to send the collected sewage to the existing Balnarring Sewerage System - located some 16km from Flinders.

Project delivery team

90 -,-- - - - - - - - - - - - - - - - - - - - - - - - -Shoreham

An important partnership for the project was with engineering consultancy MWH. The functional design of the transfer system was initially undertaken through a cost-plus arrangement which focused on engineering innovation rather than design cost control. The pump unit p rocurement process undertaken at the beginning of the project focused initially on the incorporation of telemetry within the Flinders p ressure sewer system, to resolve the kn own operational issues of existing systems. The pump supply contract for the pressure sewer pump units was awarded to Mono Pumps (Australia) . D u ring the system design phase it was identified that further system operational and co ntrol opportunities existed. To capitalise on these opportunities 'us' Utility Services, MWH and Mono extensively collaborated during the design to be able to implement a large number of innovations which have made the Flinders Pressure Sewer System uniq ue. These innovations not only reduced operational risk bur also reduced overall capital costs.

Development of the Mono pressure pump unit for the Flinders Project The development of a p ressure pump was not only tailored for the Flinders project, but also to resolve the limitations seen in other existing pressure sewerage systems. The key developments fo r chis project included: • telemetry-linked control system; • pump over-p ressure protection; • longer life rotor and stator, with a 30 year life; and • ability to undertake "on-sire" dry-well maintenance of the pump.

Telemetry linked control of the Flinders Pressure System To improve the operational issues experienced with earlier pressure systems a telemetry interface was incorporated in to the Flinders p ressure sewerage system. T his telemetry interface allowed the system to have: 84 JUNE 2008

Water

-

--,

- ~~hL8YeL __ ___________ ______ __ _ Tank

70

-

60

~

50

0

South East Water's alliance with Thiess and Siemens - 'us' - Utility Services - was responsible for delivering this project. However, due to the technical difficulties that needed to be overcome, a highly innovative approach needed to be adopted for the design and pump unit procurement aspects of the project.

.,

Existing

------- - - -- - --- - ------ ---- -- -- smn~rtng Transfer ----------- -SPSMt ________ _ __ _ Salnarrina. __ _

---- -eontrot- -Valve

20 10

Creek

- - - i=-acifftv - -

- - - - - - -- - -MeAtM - -- - - - - -- - - -- - --- - -- - - - -- - - - - - - -- - -Creek

0+-----,----,------,----,----...------,------~----l 10000 0 2000 4000 6000 8000 12000

Chainage (m)

Figure l . Flinders/Shoreham Transfer System - Vertical A lignment. • a radio link to each pump in the system, removing the customer interface for pump operation;

regularly close to their rated pressure of 60m , without having any detrimental effect on the life of the pump.

• a remote "global shutdown system" to be used during failure or leak events, to shut off all pumps within a system remotely (significantly reducing system shut-off rimes which reduces the risk of any potential sewerage spills to the environment); and

Rather than over-design ing the system to allow even the most hydraulically disadvantaged pumps within the system to be able to pump during all peak operating scenarios, over- pressure protection was also used to engage the storage of the most hydraulically disadvantaged pumps in the system d uring daily peaks. Therefore, the most hydraulically disadvantaged pumps were designed to p ump only d uring 90% of a peak day. During the ocher 10% of the day - when the pressures in the system will be above 60m - the over- pressure protection will stop the pump from operating, engagi ng the property's storage in the p ump unit's tank.

• ability for operations staff to obtain pump unit information remotely fo r fault d iagnosis, prior to attending pump "call ours" or for system performance monitoring.

Use of over-pressure protection as a pump protection and control mechanism To ensure that pumps do not operate when they see pressures above the pump's rated design pressu re, the Mono pressure pump has an electronic current sensing overpressure protection. T his protection ensures decreased stator/rotor wear and increases pump life. In chis application it is p ossible to use a current sensing device as the pressure seen by each Mono pump is directly proportional to rhe amount of motor current used. Although over-p ressure p rotection was initially installed as a pump protection device - due to the high degree of accuracy of the electronic over pressure protection it was realised during the system design p rocess that it could also be used as a system control device. Using over-pressure p rotection the pressure sewerage system can be easily controlled at one point (e.g. at isolation valves), and allows easy engagement of the individual storages in each property, rather than having to manually turn off individual p umps . It was also d iscovered that over-pressure protectio n allowed the system to be designed with most pumps operating

Journal of the Australian Water Association

Flinders/Shoreham sewerage transfer system Flinders is located some 8 km from Shoreham which was also approximately 8 km from the existing Balnarring sewerage system. The transfer system from Flinders to Balnarring crosses relatively undulating terrain seeing elevations along the route between 15m and 80m AHD, with Shoreham located at the highest elevation along the route. Shoreham itself will be connected in a fu ture backlog p roject, so the design allowed for this . Due to the length and topographical issues associated with the transfer system, a pump station was required at Flinders to transfer flows to Shoreham. As Shoreham is located at the h ighest point along the transfer system it was decided that a gravity system could be adopted for the transfer system from Shoreham to the existing Balnarring sewerage system. T h e Flinders/Shoreham transfer system consists of the following components (Figure 1):


NOT SURE ABOUT PRESSURE SEWER?

TALK TO US Pressure Sewer Services Australia Pty Ltd Your independent Australian owned company providing professional services in the following areas: Consultancy Services:

Product Supply:

• Concept Design • Full Hydraulic Design & Analysis

• Stainless Steel Boundary Isolation Valve Kits including access box

• On Property Design including Plumbing & Electrical Audits and Inspections

• Stainless Steel Flushing Points with concrete lid

• Feasibility Studies

• Pipeline Marker Post's with specific pressure sewer marker plates

• Project Estimates • Product Procurement Analysis • Community Consultation including open days and product demonstrations • Project Management • Installation Training

• Coloured steel pump cable conduit poles • 10OO's of pump units installed and hydraulic designs completed to date across Australia.

• Servicing and Maintenance Training • Pump Unit Commissioning and Pre Start Checks

Construction: • Reticulation Installation including horizontal directional boring • Pump unit installations including tank drilling up to 1350mm in diameter • Discharge pipeline installations including stainless steel pipework • Electrofusion and Butt Fusion welding • Plumbing & Drainage Connections • Electrical Works

Why waste time talking to companies who do not specialize in Pressure Sewer? Talk to us, Pressure Sewer is our business.

Find out more at www.pressuresewerservices.com.au Phone - 03 9703 2277 email - info@pressuresewerservices.com.au


technical features

pressure sewerage • Flinders Transfer Sewerage Pumping Station; • Flinders co Shoreham Rising pipeline; • Shoreham High Level Tank; • Shoreham co Balnarring induced head pipeline; and • Balnarring Flow Control Valve Facility

Flinders transfer pump station Having a pressure sewerage system upstream of the Flinders Pump Station, the pump station needed co be designed co manage potential large variation of incoming flows. Typical flows from the Flinders pressure sewerage system would see a daily peak at around 20 1/s, however, in a power outage recovery scenario the flows into the pump station can be as high as 120 1/s. An opportunity was also seen co use the contingency storage within the nerwork, where each property has up co 24 hours of emergency storage within each pump unit.

Figure 2. Cross-section co ncept plan of th e Flinders Tra nsfer Pump Station wi th sealable wet well. Shorehsm High Level Tenk Level A: Valve Opens (Normal operation)

Rather than designing a traditional wet well pump station - with large contingency storages co buffer the potential peak flows the technical solution developed fo r the Flinders pump station was co use a pressure vessel as a sealable wet well (Figure 2). Flooded Section

The pump station pressure vessel is designed co operate in a number of modes: • normally at atmospheric pressure with an open air release valve; • with the pumps controlled by wet well levels (like rypical pump stations); • as a wet well that can fill, seal and become pressurised in an emergency situation; • when operating as a pressurised well the pressure would trigger the "over-pressure protection" in each individual pump unit within the PSS and engage the emergency storage within each property (which already have 24 hours storage capabiliry incorporated within them); • as a control mechanism, which can throttle back flows from the upstream pressure sewerage system, by limiting the flow into the pump station; and • with no emergency storage as is normally required at pump stations D ue co the high head and low flow pumping requirements of the system (i.e. 150m head@ 20 l/s), the pump station also required the use of progressive cavity style pumping.

Shoreham to Balnarring induced head pipeline The transfer pipeline from Shoreham High Level Tank to the Balnarring Outfall PS 86 JUNE 2008

water

Existing Belnsrring Transfer Wet well (SPS819)

Balnerring Control Vslve Fecility

Figure 3. Shoreham High Level Tank to Balnarring - Control System Schematic. falls approximately 50m which meant it could operate by induced head with flows at approximately 35 1/s . This transfer system then discharges into the existing Balnarring Outfall System, which is also an induced head system, with booster pumping during peak operation. The location of the Shoreham High Level Tank was selected co maximise driving head while ensuring the location was as far as practical away from private residences. The Shoreham High Level Tank has been designed similar co a traditional pump station with wet well and emergency storage. Its operation is also similar co a pump station with the Balnarring Control Valve opening when a set level is reached in the tank and when the tank empties the valve closes. The purpose of the Balnarring Control Valve facility is co prevent the Shoreham co Balnarring transfer main from draining which would cause odour issues (when foul air would be purged during system refilling) and ensures pipeline cleansing flows are

Journal of the Australian Water Association

achieved, which is important as the Shoreham co Balnarring pipeline includes an extremely long flooded section. The operation of the Balnarring Control Valve is shown in Figure 3.

Conclusion This project is being successfully delivered and has shown the benefits of developing technical partnerships co deliver robust innovation. The innovations implemented for this project can now set a standard co be used in future Pressure Sewerage Projects.

Acknowledgments The author of this report would like co thank both Mono Pumps (Australia) and MWH for their contributions co chis innovative project.

The Author Steven French is a Senior Design Engineer for 'us' - Utility Services/South East Water, Victoria, email: Steven.F rench@usus .com.au


refereed paper

RURAL WATER SUPPLY FOR BALI: OFF-SHORE DESIGN BY YOUNG ENGINEERS K Third, 0 M Fun, J Bowen, A Micenko, V Grey, T Prohasky delivering long-term social and technical solutions (Bowen 2006; Bowen & Acciaioli 2007; Bowen 2008, this issue).

Abstract

The community ofTenganan in eastern Bali, fndonesia, requested technical assistance in 2006 from In January 2007, EWB Bali Engineers Without Borders ,:'Knr commissioned an Australia-based Australia (EWB) to improve the team to design the water design quantity and q uality of water supply system upgrade, which is delivered through their water the first time an offshore-based supply system. For the first time, design team has been applied to EWB is undertaking the des ign an EWB development project. phase for the water system by an 50km Volunteers have been seco nded off-shore design team and in T enganan since December Tech nical Assistance Network 2007 to implemenr the design (TAN) based in Australia, enabling Figure 1. Ma p of Ba li showi ng the location of Ten ga na n and carry out construction, young engineers to develop skills and the Karangase m region. commissioning and capacity and experience in development building. Through this project, work without having to leave the eastern region of Bali, Indonesia, has EWB is pioneering the use of a "bottomcoun try. This paper outlines the advantages requested technical assistance from up" approach for the deli very of an of ch is innovative approach for the delivery Engi neers W ithout Borders Australia infrastructure project. EWB believes chis of an overseas rural infrastructure project, (EWB) to improve the water quantity and project will be a milestone for the as well as the ch allenges, limitations and quality delivered to their communi ty. This nisation and sec a positive example For orga lessons such as establishing appropriate is a unique development project in which fut ure development projects. design criteria and the co-ordination of the Tenganan co mmunity have idenrified simultaneo us activities across Australia. their own needs and developed their own The Tenganan Water Supply concep tual solution to the problem. This is Problem Introduction known as the "bottom-u p" approach in Tenganan is a rural community situated in development work, wh ich is believed to be The T enganan community of the poor and dry Karangasem region of approximately 4,000 people in the remote a more sustainable approach, capable of eastern Bali, Indonesia (Figure 1). The water supply problems experienced in T enganan are similar to those experienced in much of eastern Bali. T he Tenganan community is one of the few remaining traditional "Bali aga" villages, meaning "traditional mountain village", with a complex traditional social structure. T enganan consists of five sub-communities; all have problems with the quantity and quality of water available For basic consumption. The community currently obtains water from a variety of so urces including the nearby Buhu River, wells, and a local spring (Batu Asah). However, the quality and quantity of supply from

View of the Buh u River from the western hill of the Te ngana n valley, with volcano Mt Agung in the backg roun d .

Engi.neers Without Borders adopt an innovative approach to rural water supply.

Journal of the Australian Water Association

Water

JUNE 2008 87


technical features

international action

refereed paper

these sources varies significantly and is not adequate to sustai n a basic quality of life. During the initial phase of the project in 2006, an EWB volunteer, Jerome Bowen, sp ent five months in the Tenganan communiry as part of his H onours thesis in anthropology and environmental en gineering. Jerome consul ted with community members to characterise and analyse che physical and social sicuacion and to build the community capacity to decide whether development action was appropriate and what action was required. The Tenganan community had an established water management group, the PSAB, which h as been assessed as displaying a "reasonable" level of management capacity (Bowen 2006). Following Jerome's in-country placement, the Tenganan community decided chey need technical assistance to resolve their water crisis. In Sep tember 2006, they officially requested the assistance of EWB, in partnership with che local NGO Yayasan Wisnu, co achieve the following main objecrives: • to increase the water quanrity in the distribution network to provide "sufficient" continuous water supply for the current and future population; • to improve the water quality of the distributed water and;

• co increase che capacity of the community th rough education co maintain and sustain their water infrastructure. The community specifi ed that the water treatment system co be implemented needed co meet the following conditions:

Community Liaison Representative

Water treatment design manager

Sponsorship

Drafting

and marketing

Pipe distribution

network design manager

Water Supp ly System

Education and

Maintenance

capacity building

Strategy

planning

Construction management & procurement

Figure 2. Overview of Tenganan Technical Assistance Network (TAN) project structure and sub-components. is located in Perch, Australia. The team relies on support from the Technical Assistance Network (TAN) of approximately 20 volunteers across Australia from different organisations, including water utili ties and engineering consultancies. Members rely on modernday information technology to communicate and develop che design. The Australia-wide team approach is working very well so far due to the multidisciplinary skills brought into the project and access co broad networks. The TAN is sub-divided into specific cask groups as outlined in Figure 2, with a volunteer leading each task group. The project manager, Kacie Third, oversees all aspecrs of the project and co-ordinates with che com munity liaison representative to ensure all key decisions are communicated to the community. The community liaison representative, J erome Bowen, plays an important role in the design process as he knows rhe key community members and is fami liar with che social complexities.

Information was shared between the different groups during regular fortnightly design meetings conducted ar Engineers Australia faci lities. Ar each design meeting, appropriate actions were decided on co progress che design until the next meeting. This approach ensured continuity of design, which was at times difficult because the volunteers worked on the project in their own rime and sometimes could nor complete che assigned casks due co busy schedules . Regular meetings curned our co be the key co ensuring uncompleted tasks gee allocated co available volunteers co keep the design progressing forward.

Establishing Appropriate Design Criteria Perhaps the largest challenge in the project

co date has been in establishing appropriate

design criteria for rhe Tenganan sicuarion , particularly in resisting the inclination co impose international standards on the • no mechan ical equipment or chemical design. According ro Dangerfield (1983), dosing system requirements; when considering the supply of water to low-income communities, it is important co • the pipe distribution network shou ld be Community consultation has occurred ar recognise that a level of service co entirely gravity-fed; each project milestone to ensure the international standards cannot always be • the water treatment system should have outcome is in line with rhe community achieved. T h e T enganan design team very low maintenance requirements; expectations. initially aimed co achieve World • the treatment process should Health Organisation (WHO) have low or preferably no Number of Individuals in Tenganan Pegeringsingan standards. However, after overhead costs and should be built encountering several challenges co ., 1000 by the community using cheap this approach and after iii and readily available construction discussions with experienced -5;; 800 materials; water practitioners in i5 .!: 600 • the community is co supply all development projects, it was 0 labour, however, only unskilled recognised that these water quality ~ 400 labour is available. standards were not practical, E :, because the system required co z 200 The Project Structure and ach ieve these standards could not Approach be operated or maintained and a 0+---~.....----~---~--~.....-----, very high water quality could not 1960 1980 1990 1970 2000 2010 For the first time, EWB is Year be guaranteed. Whilst establishing undertaking the complete design the design criteria fo r the phase for the water system by an Figure 3. Population of Tenganan Pegeringsingan over Tenganan community water off-shore design team based in time. Data for 1962 - 1994 obtained from Breguet supply system has been Australia. The project (1995). Data for 2005 obtained from Tenganan che offshore-based challenging, management and core design team Pegeringsingan records .

88 JUNE 2008

Water

Journol of the Australian Water Association


technical features

international action

refereed paper

design ream worked through rhe issues and decided on rhe appropriate criteria, in co nsultation with rhe community, to progress the water treatment system design. These design criteria are ouclined below. Population growth

Determining an appropriate growth figure for rhe wide-spread Tenganan community was difficult, si nce rhe only records were for the central village. The data (Figure 3) paint an interesting picrure. From 1962 1998 , rhe annually recorded figu res showed char the population grew steadily ar arou nd 0.7% per annu m. The data recording sudden ly stops in 1998 ar a figure of 620 and is followed by one fig ure in 2005 of 950 people. According to the community rhe fi gure of950 people is very reliable. We can only speculate on the causes of the sudden increase posr- 1998. le is possibly due to rhe improvements in public health in Indonesia over recent years, or an increase in tourism to T enganan Pegeringsingan. T he year 1998 also happens to coincide with rhe fall of the Suharto regim e. The difference between the 1962 and 2005 values represents a long-term population growth race of around 1.5% per annum. Given rhe improving living conditions in Bali, ir could go higher but ir was decided to adopt 1.5% per annum over the proj ect design horizon. Design horizon

While a typical design horizon for water infrastructure in developed countries lies in the order of 15 to 20 years as a minimum, rhe situation is quite different fo r developing communities. For T enganan, considering the uncertainties, it was decided to reduce rhe design horizon to 5 years and to build a modular water treatment system, particularly sin ce Sanchez er. al. (2006) suggested that there is liccle economy of scale in rhe construction of a multi-stage filtration system, Water consumption per capita

The in itial design used a water consumption figure adapted from rhe guidelines of developed countries of I 00 lirres/capira/day (led) . The quantity of water delivered and used fo r households is an important aspect which influences hygiene and public health. However, defining a minimum qua ntity fo r basic needs has limited sign ificance as the volume of water used depends on accessibility, reliability and potential cost (Visscher, 2006) . In the central villages in the Tenganan sub-communities, rhe community has access to water via stand pipes (piped water taps) rhac are located

A local vil lager co llecting water at the Batu Asa h spring.

approximately every 100 m. There are no in-house co nnections, and in some areas the distance to the stand pipes is sign ificancly longer. Howard and Bartram (2003) provide guideli nes on determi ning the water requirement to promote health for different accessibility scenarios. Accordi ng to the guidelines, the Tenganan siruation lies between "intermediate access" with an average per capita consumption of 50 led and "basic access" wirh a requirement of 20 led. Several other published sources (Dangerfield, 1983, Visscher, 2006) suggested a si milar range of water consumption levels for rural situations ranging from 20 - 80 led. Based on the consideration of the above guideli nes and other literatures, the EWB design team estab lished a mid-range per capita water consu mption of 40 led which is accepted as the uSL1al figure for standpipes. Source water and treatment selection

T he initial water source recommended by the Tenganan communi ty was the Macang canal, which is a man-made canal originating from the Buhu River primarily used for irrigation. During the design development, a multi-criteria analysis was performed for a number of different water sources in rhe catchment, incl ud ing criteria such as reliability of source water, quality, political issues, hydraulic head, ease of construction and catchment protection or chance of gross pollution. The analys is showed chat the Macang canal proposed by rhe com munity is nor the most suitable water source and char an existing government dam across the Buhu River, Babi T unu, is a preferable water intake site. The Buhu River is used for multi ple functions, including on-sire sanitation systems, animal watering and grazing along

the river, bathing and irrigation. During the design process, EWB considered a treatment system appropriate to the risks associated with this particular water so urce. The co mbinatio n of coarse gravel filtration (pre-treatment) and slow sand filtration treatment was selected due to its proven effectiveness in removi ng microbiological contaminants, turbidity and nutrients. The low-cost and low-maintenance fo r operation of the system also met with the requirements set by the Tenganan commu nity. Slow sand filtration as a sole treatment seep is not sufficient in red ucing faecal coliforms to a low enough level fo r potable co nsumption and hence a postfiltratio n disinfection process wi ll be required. Disinfection

The Tenganan community expressed a desire for not disinfecti ng the treated water supply. However, the design ream felt chat, in view of rhe high levels of poll ution, disinfection should, at lease, be investigated and assessed for suitability before discou nting the option. The community currencly boils all water before drinking; a social habit stemming from long periods of using polluted water sources. They have stared chat they will conti nue to boil their water after the implementation of the created water system, regardless of its microbial quality. T he community also specified that rhe created water should have improved caste and no odour properties. Key commu nity members have stated chat chlorination would result in a "strange" taste that is fo reign to rhe co mmunity, which is highly likely to resul t in nonacceptance of rhe new water supply, rendering ir redundant. T hese factors were considered when assessing the disinfection options.

Journal of the Australian Water Association

Water

JUNE 2008 89


technical features

international action

refereed paper

Other disinfection methods were assessed. Solar pasteurisation was not feasible due to insufficient continuous sunligh t and UV disinfection proved to be cost p rohib itive. Based on the cultural and community preferences, it was decided not to include disinfection in the project scope. Instead, the p roject team will focus on educating the community how to avoid cross-contamination in the handling of their boiled water in storage, transport and use (e.g. by storing off ground, using ladle, preventing touching of the bottle lids, etc).

Water supply network capacity Tenganan has an existing p ipe network that carries water from the sp ring at Batu Asah by gravity co various storage tanks within che sub-communities. The culmination of the above design criteria results in a water supply requirement of210 kL/d for the implemented water supply system, which is considerably less than the originally estimated 600 kL/d for international design standards. EWB hydraulic assessment of a lowered water consumption figure demonstrated that the present pipe networks have adequate capacity and upsizing of rhe pipes was nor critical. A derailed condition su rvey of rhe present pipe network could be pare of the capacity build ing program and if required, a followup project for pipe network rehabilitation in future. This avoids abortive work ar chis stage, which is particularly important given the limitation of capital funds.

Conclusion For the first time, EWB Australia is undertaking the design of a rural water supply system, by an off-shore design team based in Australia. W h ile rhe off-shore d esign approach brings with it many advantages, su ch as rhe accessibil ity to multi-disciplinary skills and extensive engineering networks, the approach has also presented a number of challenges. The largest challenge was the inclination to impose international standards o n che design criteria, despite these standards being largely unachievable for rural development. Mose volunteer engineers have built up their expertise in d eveloped countries, applying design criteria appropriate for their environments. However, in develop ment projects, considerat ion muse be given to a different range of conditions as che design criteria from developed countries are no longer appropriate. They key co establishing ap propriate criteria proved to be d iscussions wirh expe rienced aid-related water engineers and review by specialises in the field.

90

JUNE 2008

Water

Project Manager Katie Third and Design Leader, Mei Fun, visit the local spring at Batu Asah with prominent community members, I N yoman Sadra, I Wayan Widia and I Made Suarnatha. In aid-related development projects there is often a "carch-22" situation, whereby young engineers are keen to develop che required experience and skills in aid projects, but are not assigned co aid projects due to a lack of experience. The innovative approach ap plied by EWB to che Tenganan project has allowed a number of you ng engineers to gain related experience and ski lls, for application to future projects provided volunteer engineers are mentored by senior engineers with in- country experience to provide che dep th of knowledge relevant to developing countries. EWB is now applying this approach co several other projects given its p roven value in develop ing design and supportin g offshore develop ment projects.

The Authors Dr Katie Third is the Australia-based project manager and is a process engineer with Si nclair Knight Merz. Kacie has around 10 years exp erience in water and wastewater projects in both d eveloped and developing countries, Kthird@skm.com.au. Mei Fun is a senior civil engineer wich Black&Veacch and is che Tenganan water creacmenc design lead. Jerome Bowen is the Community Liaison and is an environmental engineer and anthropologist currently working full- time with WorleyParsons and part-time as the Program Director for che Western Australian Chapter of Engineers With out Borders. Alice Micenko and Vaughn Grey are graduate engineers working with Sinclair Knight Merz and Tim Prohasky is che Indonesia Program M anager of EWB Australia .

Journal of the Australian Water Association

References Bowen J (2006) A multidisciplinary look ar capacity development and its applications th rough the characterisation of water resources in Tenganan, Indones ia, Honours D issertation, University of Western Australia, Perth, Australia. Bowen J, Acciaioli G (2007) Improving the success of "bottom-up" development work by acknowledging the dynamics among stakeholders - a case st udy from an Engineers W ithout Borders water s upply project in Tenganan, Indonesia. ASPIRE Conference Water and Sanitation in the Asia-Pacific Region: Opportunities, Challenges and Technology, 28 October - I November 2007, Perch, Australia. Bowen J (2008) EWB in Action. Water 35, 4. Breguet G, Ney R (1995) From Isolation ro Modernity: Demographic transition and public health changes in T enganan Pegeringsingan (Bali) over rwo decades: 1976 - 1995, Ann ual Internacional Meeting of the Society for Balinese Stud ies, Denpasar, Bali . Dangerfield BJ ( 1983) Water Supply and San itation in Developing Countries, Water Practice Manuals 3, p. 265 The Inst itution of Water Engineers and Scientists, London, England. Gleick, PH (1996) Basic Water Requirements for Human Activities: Meeting Basic Needs. Water International, vol. 21, p87. Howard G, Bartram J (2003) Domestic Water Quantity, Service Level and Health. Geneva, Switzerland, World Health Organisation. Sanchez LO, Sanchez A, Galvis G, Latorre J (2006) Multi-Stage Filtration (Thematic Overview Paper 15), The H ague, The Netherlands, !RC Internacional Water and Sanitation Centre. Visscher J T (2006) Facilitating Community Water Supply Treatment - From transferring filtration technology ro multi-srakeholder learn ing, T he Hague, The Netherlands, ]RC lncernational Water and Sanitation Centre.


refereed paper

EWB IN ACTION J Bowen Engineers Without Borders Australia works with disadvantaged communities to improve their quality of life through education and the implementation of sustainable engineering projects. Through the process of helping people in need we become more socially aware and responsible, improve ourselves and inspire others to action . EWB's vision is of a world where every individual and community has adequate access to the resources, knowledge and technology necessary to meet their self-identified human needs. Fundamental to our vision is the conviction that each individual has the ability and the responsibility to make a positive impact in the world. For more information please visit the EWB website at www.ewb.org.au. Bukit Kangin Sitting in the staff room of the primary school at Bukic Kangin was a su rreal experience. Ir felt like a staff room in Australia. I th ink rhar anyone who has been in a staffroom anywhere will know what I am talking about. The room was set up the same way, rhe people inside interacted in rhe same way, the people inside were the same. Most similar of all, rhey wanted rhe best for their children. Am idst their answe rs co my questions like "what is your current situation wirh d rin king water" and "what muse EWB co nsider if they are co undertake a project with your commu ni ty co solve your water problems", rhey managed ro slip in requests for books, English reachi ng and orher resources co help their students get into high school. Outside rhe room it is very different. Bukir Kangin (the name means "hill east" in Balinese) sics atop a 260m high ridge that runs from the fa r north of the village lands of Desa T enganan co rhe ocean near a remote tourist destination called Candidasa. While only 3km as the crow flies from Candidasa, rhe steep slopes of rhe bukit means an 18 km trip by motorbike along windi ng forest roads, and rhar the children stared at me until they realised char I was friendly and then treated me like a big dog. I had come co Bukir Kangin in Eastern Bali co talk with Pak Wijaya (o ne of rhe teachers) and Pak Merta (an ex-army officer) regarding their community's part in the intricate physical, environmental and socio-political web rhar is rhe drinking and irrigation water realiry of Desa T enganan. Ir certainly is a web. As noted by Clifford Geercz, a prominent anthropologist in this region, Balinese political processes are strongly shaped by topography (Geerrz 1980). T opography dictates the flow of water, as we know from engineering, and in Bali, water is power. Bukir Kangin lies in the traditional adat lands of the warrior

After a one hour trip down a 250m steep hillside accompanying some locals to collect water, I was self-conscious enough to offer to carry the water bottles of the small boy in the foregrou nd. It was embarrassing as I strugg led the two hours back up. This kid does this twice a day so his family ca n wash and cook.

people of T enganan Pegringsingan, rhe village at the centre of Desa T enganan. Inhabited by tenant farmers, rhe Bukir Kangin community is tied eco nomically and socially co rhe village of their landlords. Their drinking water comes in a pipe rhar must pass through different adat lands further upslope. T his means chat they must negotiate, often unsuccessfully, with this other adat village for access co water. If unsuccessful, it is back co building dams in gulli es to catch rainwater and trekking two hours co their only spring.

Scoping the Project This was just one day, and one small part of Desa Tenganan's water resource

Integration with social structures is the key to success.

characterisation, a scoping project chat turned into the Tenganan Water Supply Project, the largest construction project undertaken by Engineers Without Borders ro dare (see Third et al, 2008, rhis issue). During th is scop ing phase of the project, I spent fi ve months in rhe community talking with community members about their physical and social water situation, and working with them on ideas for improving ir. Th rough chis capacity development, the outcome was a co mmuni ty decisio n rhar they wanted EWB help co improve their water situation, and a scope for how they wanted EWB co help them. Proper capacity development, such as this, allows initiatives co come from rhe communi ty, a core philosophy of the Tenganan Water Supply Project. By rhe community requesting our aid and dictating the project direction, the possibility of project success is maximised (Bowen, Acciaioli 2007).

Journal of the Australian Water Association

Water

JUNE 2008 91


technical features

international action There is plenty of engineering involved pipes, bores, wells, dams and river catchments - bur the more I learnt the more I realised that a large slice of development is social. I came co Tenganan as an EWB engineer co build something, but left as an engineer who co ntributed knowledge, so chat the community could inform EWB what they wane co build. I had rapidly learnt char introd ucing offers of development aid into an established comm unity was do omed co fail if it confl icts with traditional practices.

Traditions and Culture For example, desa is a Balinese and Indonesia n term chat can (admittedly somewhat simplistically) be defined as the village unit, the geo graph ical area owned by the village unit, as well as the social sphere char incorporates the desa lands and all the people within it (Warren 1993). T he desa is d ivid ed into five sub-groups called banjar, described as m u tual aid groups with ritual, social a nd administrative responsibilities . Warren describes the banjar as ' perhaps the most powerful o f local corporate institutions' . T enganan can also be d ivided accordi ng co adat, the traditional fo rms of social organisation and regulation, and dinas, the official government structures of organisation a nd regulation . However the borders of the desa adat and the desa dinas, do not coincide, and banjar adat and banjar dinas h ave similar geographical d isparities. The tension in social relations created by such d isparities, commonp lace all over Bali, must be confronted co achieve project success. The cultural complexity inherent in Tengana n due co the adat - dinas and desa - banjar groupings meant char systems of rights and obligations were important to consider in determ ining wh o constituted "the com munity" and who represented what constituency in decision-makin g on the commun ity's behalf. I n the end, it had to be the sub-commu nities who decided am ongst themselves to define their "com munity" as the dinas grouping, which then became the appropriate project service

92

JUNE 200 8

Water

area. Goodness knows the reaction if I had walked in saying "I know you have problems with water, EWB knows how to solve chem". Another example is irrigation . Balinese wet-rice farmers adhere closely co a set of irrigation ceremonies and schedules as specified by a complex socio-religious struc ture. This structure is centred around management of water usi ng water temples and water-user groups called subak (Lansing 1991) . This is an adat (traditional) structure for managing water allocation and crop cycles, rather than a Government con trolled sys rem of metered allocation as we m igh t see in Western Co unt ries. This system has produced rice on a continuous basis three times a year for, in some regions, up to 1,0 00 years. Through this sustainable system the overuse of a common resource, in this case water, which is also called the "tragedy of the com mons" (Hardin 1968), is avoided.

The key to success Not accounti ng, in a project, for suc h a powerful and robust socio-religiou s system could have negative repercussions fo r a developm ent project, as vividly described by the anthropologist Stephen Lansing in his 199 1 book Priests and Programmers:

technologies ofpower in the engineered landscape of Bali. D uring the Green Revol ution in Indonesia in the 1970s, through a set of political, technical and financial pressures, Balinese fa rmers abandoned the water temple system and instituted the Green Revolution methods for rice c ultivation. This optimised crop yields using genetic engineered seed , c hemical ferti lisers a nd faste r, ad hoc cropp ing cycles. Ac fi rst there were bumper crops bur it cook o nly 2-3 years uncil pest explosions, degraded soil and lack of water saw far mers indebted to seed companies and yields plummeting. Lansing and a team o f ecologists identifi ed che lack of cropp in g cycle o rganisation as che cause, prompting che regional government co return irrigation management to the water

Journal of the Australian Water Association

refereed paper

te m ples . Balin ese wee-rice agriculture recovered over the fo llowing decade and continues co be m anaged by socio-religious structures, cycles and ceremon ies co chis day. We have fou nd char in T engana n , indepth knowledge of and integration with social structures is che key to project success. By emphasising capacity development over the technical side co the project, community involvement was maximised, increasing owne rship over the project, working cowards building their ability to successfully construct, maintain and manage their own water supply system .

The Author Jerome Bowen is an environmental engineer and anthropologist with WorleyParsons, as well as the Programs D irector for the Western Australian Chapter of EWB. For fu rther information, contact: jerome.bowen@worleyparsons.com

References Bowen, J P, Acciaioli, G ( 2007) 'Improving the success of "bottom-up" development work by acknowledging the dynamics among stakeholders - a case study from an Engineers Without Borders water supply project in Tenganan, Indonesia.' in ASPIRE: Water and Sanitation in the Asia-Pacific Region: Opportunities, Challenges and T echnology, Perth, Western Australia, October 2007. Geerrz, C ( 1980) Negara: The theatre state in nineteenth-century Bali, Princeton Universiry Press, Princeton . Hardin, G (1968) 'The Tragedy of the Commons', Science, 162, No. 3859, pp. 1243-1248. Lansing, J S ( 1991) Priests and Programmers:

technologies ofpower in the engineered landscape of Bali, Princeton University Press, New Jersey. T hird K, F un OM, Bowen J, Micenko A, Grey V, Prohasky T, 2008. Rural Water Supply for Bali: Off-shore Design by Young Professionals. Water 35 No 4. (this issue) Warren, C. 1993, Adat and Dinas: Balinese communities in the Indonesian state, Oxford University Press, Kuala Lumpur; New York.


technical features water supply

POINT OF ENTRY TREATMENT FOR RURAL SUPPLIES S Gray, E Ostarcevic, D Dharmabalan, L Fiedler, A Jayaratne Abstract A number of Victorian water utilities supply untreated water to a small number of customers generally in remote areas. These customers commonly known as Supply-by-Agreement customers are routinely advised chat their water supply is uncreaced/parcially created and hence nor suitable for human consumption or food preparation. Ocher water authorities such as GWMWater supply water to 41 communities in the north western region of Victoria chat is nor suitable for consu mption. T he Viccorian Safe Drinking Water Regulations 2005 require Scace water ucilicies to com municate to these customers che status of their water supply. Point of en cry (POE) treatment systems were trialled at three water ucilicies in Victoria to assess their ability to reliably de! iver potable water over a period of several months. These systems were assembled from commercially available treatment units and were reseed on different water qualities. The trials indicated char POE systems produced potable grade water throughout che resting period, and char che capital cost of these systems may be cheaper than centralised treatment for cowns of less than 150 households. However, the most appropriate management model fo r POE systems (i.e. water quality monicoring and main tenance) still requires debate and will affect che coses of implementing these systems. T his paper describes the outcomes of che invescigacions u ndertaken for the research project "Small Town Water Supplies" by che Cooperative Research Centre for Water for Water Quality and Treatment (CRC) project on behalf of che project sponsors DSE and GWMWacer.

Introduction Grampians Wi mmera Mallee Water (GWMWacer) supplies 41 cowns with uncreated, reticulated water and another 17 cowns with water created by chlorine

Cost effective quality for small communities.

Figure 1. M obile PO E water treatment system at Lexton. disinfection only. Similarly, Central Highlands Water (CHW) has five small cowns supplied with reticulated water and inadequate treatment. Yarra Valley Water has 670 remote customers, or about 0.1%, supplied with non-potable water. The small populations of these systems (<200 people) and their remote location make centralised water treatment expensive. Point of entry (POE) treatment was explo red as an alternative means of delivering potable water co these small, remote communities. In considering such systems, the ability co source che creacmenc devices, che treated water quality and the reliability of the POE systems was considered.

Experimental T he use of commercially available point of entry (POE) and point of use (POU) treatment unics co provide drinking water from poor quality water sources was invescigaced. Three different POE mobile water treatment planes (MWTP) were assembled and trialled at six different raw water sources th roughout Victoria (Gray et al., 2008). The three MWTP consisted of: • a sand fil ter, carbon fi lter, cartridge filter, UV disinfection, storage; • a sand fil ter, carbon filter, cartridge fi lter, UV d isinfection, storage and reverse osmosis (RO) for saline wacer sources; and

• two ulrrafiltrarion (UF) units manufactured by Homespring™, GE Water and Process T echnologies, Canada with a pre-filter (cartridge fil ter). The maximum flowrace through the treatment systems was limited to 4 Umin for systems chat included a UV disinfection unit, so as co keep che flowrate below the maximum allowable fo r reliable disinfection. Th is low maximum flowrace necessitated the use of a treated water storage tank co provide peak flows via pumping from the rank. T he Homespring uni cs did nor require created water scorage, as chey were able co effectively treat water at a limited peak demand flow. T he MWTP were reseed at che followi ng locations: • Rupanyup (GWMWacer) - disinfection only with trihalomethanes (THMs); • Horsham (GWMWacer) - irrigation water with high turbidity and microbiological concentrations; • Dadswells Bridge (GWMWacer) groundwater with high iron and manganese concencracion (Fe/Mn); • Lexco n (CHW) - high turb idity, colour and microb iological concentrations; • Avoca (CHW) - grou ndwater with high salinity;

Journal of the Australian Water Association

water

JUNE 2008 93


technical features

water supply • Woori Yallock (YVW) - aqueduct water with high turbidity, colour and microbiological concentrations.

T he media filtration units trialled were Waterways media filtration systems and were filled with sand or carbon. Several RO units were tested: the GE Merlin TM RO, Dow FilmtecTM and Hydranautics™ membranes. Results

E.coli and total coliforms were effectively removed by all three MWTP and the UF, with no E.coli or total coliforms detected in any of the treated waters. The UV units used in the MWTP performed reliably, and this was attributed to limiting the flow through these units to less than their maximum design flow-rate fo r the UV unit and having effective pre-treatment, while the UF units effectively filtered the microorganisms from the water. The UF units demonstrated an ability to maintain water quality even when spikes in E.coli and total coliforms were detected in the feed water. Bacterial re-growth of H PC bacteria was, however, found inside the clear water tank at Avoca and Timberline Road. It is recommended to disi nfect the clear water rank once a month by adding a chlorine tablet. No re-growth of E.coli or coral coliform bacteria was found in the clear water tanks. Turbidity was effectively removed by rhe MWTP in all trials, with turbidities of <2 NTU reliably achieved and turbidity of <l NTU routinely achieved. The POE UF reliably produced turbidity of <0.4 NTU. The MWTP required little maintenance over the period of the trials (3-4 months), and the sand and carbon filters were automatically backwashed once a week. The UF was backwashed daily and cleaning of rhe UF was required after 2-3 months when fed water with turbidity of >3 NTU.

Figure 2. Permanent POU treatment for rainwater a nd groundwater at Avoca Primary School.

reduction by the Merlin RO unit at Avoca was 78% and produced treated water with an EC of less than 450 µSiem. The Merlin RO did foul during the trials, indicating char regular cleaning was required. A six monthly cleaning frequency seemed suitable for the Avoca water which had an EC of 3,000 µSiem. The trials at Rupanyup determined chat activated carbon in the POE unit was able to remove rrihalomerhanes (THM) from the water, with all treated water samples having less than 0.01 mg/L THM (feed = 0.138 - 0.228 mg/L). The activated carbon did not have to be replaced during the life of the trials (2 months). Where water is centrally disinfected, using activated carbon

adsorption was sufficient to deliver potable quality water to customers. Water recovery fo r both the MWTP and the UF units was satisfactory, except for the overall recovery when RO units were used. The overall water recovery varied between 70% at Timberline Road and Dadswell Bridge to 97% at Rupanyup and could be increased by longer intervals between the backwash cycles. The water recoveries through the POU RO units were only 20-30% to maintain consistent crossflow and reduce the operating pressure. Such low RO recovery may be limiting where reduced water availability, or where saline discharges to the environment is an issue.

Costs Preliminary cost estimates suggest chat POE may be cheaper than centralised treatment plants for communities less than 150 households. The technology currently available 'off the shelf can capably produce potable water chat meets Australian Drinking Water Guideline (ADWG) parameters with rhe exception of coloured water. New nanofilrration membranes have been shown to reduce colour/DOC in full scale operation. The trials completed as a result of chis project indicate chat commercially available equipment can produce safe drinking water generally at a lower cost per household than centralised treatment if a distribution per household network is in place.

Colour reduction was limited to approximately 50% for the water tested, at Timberline Road and Rupanyup. Very little colour reduction was achieved at Avoca or Lexton. Removal of colour using commercially available carbon filters was limited. The production of small scale nanofilrers char are capable of removing dissolved organic carbon char contribute to colour were nor reseed, however, they may be able to bridge the gap and provide colour/DOC removal necessary for the provision of potable water.

Management of POE systems

POU reverse osmosis systems demonstrated reliable performance for reducing electrical conductivity (EC) at Lexron and Avoca. The average EC

This project identified management of POE systems as one of the key outstanding issues to be resolved, which includes maintenance, operation and monitoring to

94 JUNE 2008 Water

Figure 3: GE Homespring unit installed at Horsham.

Journal of the Australian Water Association


technical features water supply ensure rhe supply of safe drinking water to the customer. In addition, ownership of rhese treatment facilities is an important consideration for water uriliries, consumers and regu lators . Centralised ownership of the treatment systems can impose significant resource co nstraints on water utilities. More research and consultation is required to determine the best management model to address ownership, operation, maintenance and monitoring requirements.

Future work Further investigation is required to: • develop management guidelines for POE/POU systems; • develop mon itoring regimes to protect publ ic health and assist with cost estimation for these systems; • develop maintenance schedules; and • integrate cap ital and management cost to develop lifecycle costs for direct comparison wi th other alte rnatives.

Conclusion The flow through rhe treatment system was limited to less than 4 L/min to keep within the maximum design flow rare of rhe UV disinfection un it. T he treated water was stored in a I 000 L rank and peak flows were delivered from rhe rank via a pump. W here high salinity was an issue, point of use reverse osmosis treatment was implemented. Point of entry ulrrafilrrarion units were also rested on two different water supplies. The mobile water treatment systems reliably delivered potable water over rhe lifetime of the trials (3 months), and the treated water q ual ity was potable grade. Turbidity was typically removed fro m high turbid ity water sources by the sand filter, with the carbon and cartridge filters providing additional turbidity removal during peak turbidity events to ensure effective UV disinfection. Typical colour removals were 50%. The UV disinfection unit deactivated E coli and coliforms with no E coli or coliforms detected in the treated water. This good performance was achieved by limiti ng rhe flowrare through the UV disi nfection unit and providing high quality pre-treatment before the UV disinfection un it. Regrowth of heterotrophic plate counts was observed in the storage tank over a period of approximately 60 days. This could be effectively controlled by ch lorine dosing over the rank every month. A preliminary cost estimate suggests that point of entry t reatment may be cost

POINT OF ENTRY /USE TREATMENT WORKSHOP T he CRC fo r Water Quality and Treatment held a workshop in Ballarat on the 14th May, to disseminate the outcomes of research into point-of-entry (POE) and point-of-use (POU) treatment systems to deliver drin king water quality to rural and remote communities. T he workshop provided a fo rum to engage water industry practitioners and regulators to discuss issues surrounding the implementation for rhe provision of drinking water supplies using decentralised treatment technologies. Tony Priestley, Deputy Director of the CRC chaired rhe workshop and rhe speakers at rhe workshop included: • Mr Jeff Rigby, Managing Director of GWMWater and instigator of the research, • Mr David Sheehan, Program Manager Drinking Water Regulation OH S, who spoke abou t rhe application of rhe regulatory framework to POE/POU systems, and • Researchers, Prof Stephen Gray (Victoria University), Mr Eddy Osrarcevic effective fo r co mmunities of less than 150 households, and various management models have been considered for implementation of these systems.

Recommendations Ir is advised to use all the treatment units char were included in rhe MWTP units for the appropriate water quali ty, with RO treatment nor requi red unless the raw water is saline. The flow rate through the unit shou ld not exceed the design flow-rate of the disi nfection unit to ensure microbiologically safe drinking water at all ti mes. Additionally, construction of a fail safe system should be considered, so char water is nor processed when the UV lamp is no r working. This could be achieved by detecting when there is no current flow in rhe UV lamp and then either activating a solenoid valve to prevent flow or deactivating the feed pump. A pre-filter (sand filter, a cartridge filte r or a sedimentation rank) to lower rhe feed turbidity should be installed when using an ulrrafilrrarion unit to prevent the UF from rapid fouli ng.

(Central Highlands Water), Dr. Dharma Dharmabalan (Coliban Water) and Ashok Jayararne (Yarra Valley Water) who derailed the research program and outcomes, and raised issues still to be resolved. An open forum after the presentations provided an opportunity ro rigorously debate how chis approach to water treatment could be implemented. Ir was generally agreed chat rhe project had demonstrated chat POE devices could be used to deliver drinking water from poor quality water sources, but that there were srill questions remaining as to what the long term operating and maintenance costs are, how such systems are best managed and what level of compliance monitoring is required. There was consensus that a fu ll scale demonstration for the decentralised approach was the next step in having this approach to water treatment implemented. Representations to industry bodies ro support this process have been initiated.

Department of Sustainability and Environment (DSE) and the Department of Human Services (OHS). Victoria University, CSIRO, Central Highlands Water, Gramp ians Wimmera Mallee Water and Yarra Valley Water provided in-ki nd contri butions to th is research . GHD contributed to the project via a consultancy arrangement with Central Highlands Water and GE Water and Process Technologies supplied rwo Homespring fil ter units for rhe tri als.

The Authors Stephen Gray (stephen .gray@vu.edu .au), is Director and Lea Fiedlea is a research assistant at the Institute for Sustai nability and Innovation at Victoria University. Eddy Ostarcevic is Ma nager, Treatment, Central H igh lands Water, Ballarar, Dharma Dharmabalan is Executive Manager Planning at Coliban Water, Bendigo and Asoka Jayaratne is Senior Planning Engineer - Service Enhancement Water for Yarra Valley Water, Mitcham. References

Acknowledgment The POE treatment system investigations were undertaken as part of rhe CRC fo r Water Quality and Treatment research project "Small Town Water Supplies". This investigation was made possible by fina ncial support from rhe Victorian Government

Gray, S. R., Fiedler, L., Ostarcevic, E., Dharmabalan, D. 2008. Point of enrry/use treatment for the delivery of potable warer. CRC Water Quality and Treatment, Research Report 50, htrp://www.warerqualiry.crc.org.au or http://isi.vu.edu.au

Journal of the Australian Water Association

Water

JUN E 2008 95


technical features

membrane technology

FOULING IN REVERSE OSMOSIS B Bolto, T Tran, M Hoang Abstract Analysis of the foulants isolated from foule d reverse osmosis (RO) membranes reveals simple scale deposits and, more frequently, composites of colloids, particulates and biomass chat are difficult to remove. The common scales appear to be limited to calcium carbonate, calcium fluoride and the sulphates of calcium, strontium and barium, plus phosphate when present. Responses to specific cleaning formulations have co nfirmed the identity of the scales. Scaling is generally a problem w ith ground waters of varying mineral content, and not crucial for seawater feeds. Biofouling, on the other hand, Figure 1. Regions for bulk and membrane surface can be a serious threat to all RO concentrations, and CP. operations. Biomass accounts for the major part of the organic material in Scaling fou lants. It is essential to minimise Inorganic salts can precipitate out of the favourable growth and attachment concentrate stream as the various solubility conditions. The most effective co ntrol of limits are exceeded so char deposits form on biofouling is, of course, prevention of che che membrane surface. It is cackled by colonisation or proliferation of limiting water recoveries, adjusting pH or microorganisms by disinfection. adding suitable anti-sealants (N ing, 1999;

Introduction The fouling of RO membranes is caused by ch e accumulation of materials on the membrane surface, and results in deterioration of both the quantity and quality of created water, and in higher treatment costs. Materials that can cause membrane fou ling include sp aringly so luble inorganic sales, colloidal and particulate matter, organic comp ounds and microorganisms present in feed water. Fouli ng by inorganic salts results in scale layer fo rmation and occurs when the p roduct of the co ncentration o f the soluble components exceeds che solubili ty lim it. Particulate and colloidal matter rejected by the membrane may also form compact cakes o n che membrane surface and introduce an additional resistance barrier to filtrat ion. The fouling by organic compounds is governed in part by the in teraction s of organ ic compounds with th e membrane surface, amongst themselves and with other fo ulants. As well, under certain circumstances, microo rganisms present in the feed water may proliferate and cause severe fou ling via che fo rmatio n of biofilms.

96 JUNE 2008

Water

Kumar et al. 2006). Mose scaling is by calcium carbonate, sulphates of calcium, strontium and barium, and calcium fluoride. The deposition of crystals is inhibited by anti-sealants chat suppress crystallisation. Scale control systems are well advanced following substantial effort with regard to boilers, evaporators and cooling cowers. Anionic polymers, polyphosphates and organophosphorus compo unds are used at the 1-5 mg/L level. They bind to the su rface of growing crystal nuclei and retard the rate of crystallisation from supersaturated solutions, modifying the crystal packing. Because of the very sh ore residence time in RO, of the order of a few seco nds, the concentration of seed crystals is very low and the temperature is con stant, so char high levels of supersacuracion wichou c cryscallisacion are possible. However, there can b e interference from ocher inorganic or organic material in the water. Also, anionic polymers employed as anti-sealants and dispersancs can be deposited on che membrane surface and concentrate metal

A review of the chemistry and biology offouling.

Journal of the Australian Water Association

io ns of higher valence, such as calcium, iron and aluminium species, and particularly aluminium silicates. Scaling is nor generally a problem for seawater and very h igh salinity waters. Fouling has been fou nd to be dependent on cation valency and on anion type, whether chloride, carbonate, sulphate or phosphate, with the laccer being che worst offender. Of che cations, calcium shows a higher flux decline than magnesium b ecause o f a greater concentration of p recipitated sp ecies. For calcium chloride che interaction between the cation and natural organic matter (NOM) in surface water played an important role in flux decline, caused by cake format ion on the membrane surface. The thamodynamic saturation index or S;x, which is the (ion activity produce)/ (solubility p roduct), is commonly used to assess the scaling potential. This requires th e d etermination of che relevant ionic concentrations both in the bulk solution (Cb) and in the vicinity of the membrane surface (C111). Because of concentration polarisation (C P), which is the accumulation of rejected ions near the membrane surface creating a concentrated layer, Cm becomes higher chan Cb, so the scaling potential near the membrane surface (surface crystallisation) is higher than in the bulk solution {bulk crystallisation). Figure 1 shows the notional C P region on the membrane surface. Optimal scale mitigation strategies for RO plants require the determination of: (i) the degree of C P, then che potential of surface crystall isation using thermodynamic modelling; and (ii) the scaling kinetics and interactions amongst different fou lants. Gypsum (calcium sulphate dihydrace), unlike calci um carbonate, cannot be prevented from depositing by lowering the feed water pH. Co mmercial an ti-sealants designed to mitigate the growth of gypsum , such as phosphonates, form complexes with NOM and ocher inorganic compounds. Also, chey are ineffective in preventi ng the precipitation of aluminum silicates, which are common fou lants. Under cond itions where the bulk solution is under-saturated with respect to gypsum, examination by scanning electron microscopy (SEM ) shows char surface crystallisation may result in complete


technical features

coverage of RO membrane surface with gypsum and a corresponding fl ux decline of 60% (Figure 2). While fully developed rosette structures are often observed, there are other crystal arrangements that suggest an intermediate phase in the rosette formatio n process.

Fouling by Colloidal Material and Particulate Matter Colloids can be orga nic, inorganic or composites. They are introduced by natural drainage and erosion, and co nsist of sa nd, silt, clay, etc. The colloidal matter char can be presen c in nacural waters is listed in T able l (Ning, 1999). Ferric, alum inium and manganese hydroxides and silica grow by polymerisation and cross-linking with organic and inorganic polymers into particles of increasing size char become gels and amo rphous foulanrs. Biotic debris such as polysaccharides and cell ular fragments co ntribute greacly to such fouling. Colloidal matter may agglomerate and adhere to membranes because of increased co ncentration, salini ty, compaction, flocculation surface interactions and other phys ical and chemical facto rs. The particles so formed may be large enough co be removed with 1-5 µm prefil cers. Anticoagulants and antideposicion agents also show promise in inhibiting fouling by chis material. An example of an RO membrane fo uled by a brackish water feed is shown in Figure 3 (Tran et aL., 2007). Ele mental analysis of the SEM sample was carried our by energy dispersive X-ray spectroscopy (EDXS). In this case, the fouling layer was about 3 µm chick and consisted of an amorphous organic-AI-P matrix (spot 1) embedded with alu minium silicates (spot 2).

Adsorption of Organics The adsorption on rhe membrane surface of NOM, the organic compounds present in natu ral organic matter, causes a flux decline that is dependent on pH and ionic strength (Bragherra et al., 1997). In experiments with a nanofilrrarion (NF), a hollow fibre membrane composed of a porous polysulphone support of 100-300 µm thickness onto which was superimposed a

Figure 2. Development of gypsum rosette structures on the membrane surface. PS support

Fouling layer

C Al

· .r 150

50

JI O '\ire, [Ca

jl ~i1~\Jl..

0 O '

'

2'

'

4' Kev

Figure 3. SEM ima ge and associated EDXS analysis of the fou li ng layer on an RO membrane showing an amorphous organic-AI-P matrix (spot 1) embedded wi th aluminium silicates (spot 2 ) (Tran et al., 2007).

skin layer of sulphonated polysulphone of 0.1 µm thickness was tested. The sulphonic acid groups provided a negatively charged membrane surface intended co repel the attachment of an ionic organic material. Altering rhe pH caused a change in the pure water permeate flux, which decreased with decreasing pH. This was taken ro indicate chat membrane compaction occurred as a result of reduced electrostatic cha rge repulsion within the membrane matrix. T here was a decreased rejection of both inorganic ions and NOM at lower pH and higher ionic strength. This also caused a shift in molecu lar size ro small er dimensions. The NOM accumulated at the membrane surface and impeded water flow. NOM is notorious for foul ing low-pressure membranes, especially chose char are hydrophobic (Amy et aL. , 2001 ). Pilot work on the effect of pretreatment of groundwater by ultrafiltrarion prior co NF or RO, using spiral wound membranes,

Table 1. Colloidal matter in natural waters (N ing, 1999). Microorganisms

7

Increasing magnification

Oils

Polysaccharides (gums, slimes, plankton, fibrils)

Hum ic acids, lignins, tannins

Lipoproteins (secretions)

Iron and manganese oxides

Clay (hydrous aluminium and iron silicates)

Calcium carbonate

Silt

Sulphur and sulphides

showed no fl ux decl ine even after 100 days (Gwon et al., 2003) . The removal of inorganic matter was 76-95%, and of organic matter 80-84%. Membrane autopsy revealed char the major foulants appeared co be silica bound co orga nic matter, which formed rhe first fouling layer close to rhe membrane, and Ca bound co inorganic matter, which was layered on cop of che organic material.

Biofouling Biotic life in natural waters can co nsist of many species. Numerous types of bacteria, algae, fung i, an d ocher marine microorganisms can grow in a favourab le environment even in a high saline environment. T he type, concentration and growth potential of che biological species are a fun ction of temperature, sunlight, pH, dissolved oxygen concenc and rhe presence of nucriencs. Aerobic bacteria prefer warmth, adequate dissolved oxygen, a pH of 6.5-8.5 and adequate nutrients. Anaerobic bacteria exist where there is little or no dissolved oxygen, bur need sufficient nutrients. Both types of bacteria can exist ar different locations in che same system. A useful way of preventing biofouling is co eliminate or minimise rhe favo urable growth conditions, bur many of rhem cannot be easily controlled (Saad, 1992).

Journal of the Australian Water Association

Water

JUNE 2008 97


technical features

Figure 4. G rowth of microorganisms o n an RO membrane surface.

Figure 5. Cross-sections of fouled RO membranes showing a thick fouling layer and The microorganisms can be introduced into the water system by either air or water. The simplest form of biofouling is initiated by bacterial attachment to inner piping and component surfaces, especially in low-flow dead-ended regions, bends, elbows, etc. There the fi rst layers of biofilm are formed, and as bacteria start to multiply, thriving partly on the organic matter rhat accumulates within rhe matrix of rhe biofilm from dead cells, more and more organic debris is formed and the attachment of the thickened film ro surfaces gets stronger and more complex. The deposited biofilm continues to grow, attracting free- fl oating microorganisms, organic matter and nutrients rhar are p resen t in the water. The deposits become more cohesive in structure and tougher to dislocate, even with b iocides. Eventually, some of the biofilm is sloughed off an d the bacterial population explodes into all system components, including the membrane. An accelerated build up of differential pressure across rhe membrane starts and grows in an exponential manner. W ithin a few days the fl ux and salt rejection are adversely affected, generally before any significant pressure d rop occurs in spiral-wound thin film comp osite membranes. The opposite is typically seen in hollow fib re systems, where a pressure drop is first observed. If rhe b uild up is allowed to continue there may be irreversible mechanical damage such as web material tearing; and in sp iral wou nd systems telescoping of cartridges can cake place. Microo rganisms can proliferate if media filters run for extended periods between backwashes, and if there is no adequate biostat control. P rolonged storage of polyelectrolyre is to be avoided and antiscalant solution tanks muse be routinely washed our. They can accumulate in carbon filte r beds if the beds are not sanitised at lease weekly. Ocher items to be watched are poor maintenance of backwash water storage and extended rimes in cartridge filte r operation. The co nsequences are a

98

JUNE 2008

Water

the presence of biofil m. complexity of microbiological growth , biofilm fo rmation o n memb ranes and a serious threat ro RO operation with possibly irreversible b iofouling. Examples of membrane biofouling are shown by SEM in Figures 4 and 5.

• co nventional coagulation/ sed imentation/filtration usin g ferric ch loride, alum, ionic/non-ionic polymers, and dual media fil ters

Pre-treatment

• cartridge fi ltration (used by >55% of plants)

Membrane p re-treatments to remove colloids and high molecular weight NOM have been studied extensively, with attention being given to using other mem brane technology as well as the add ition of coagulants. Pre-filtration of natural seawater from San Diego Bay with a polytetrafluoroethylene microfiltration (MF) membrane of pore size 0.1 µm reduced foul ing an aromatic polyamide RO memb rane more effectively than simulated conventional coagulation/filtration that removed particulate material of 1 µm size or greater (Kumar et al., 2006). Most fouling was by > 1 µm particles, bur MF gave a sign ificant improvement, as d id ulrrafiltrarion (UF) with a polyacrylonitrile memb rane having a 100 kD a cur off. This area has been the subject o f a recent review in this journal (Bolro et al. , 2008) . P retreatment has been found to be essential for at least half of the major RO seawater desalination plants that have been installed arou nd the world. The choice of pretreatment is dependent on local facto rs that need to be assessed in pilot studies. Iterns to be considered are: • removal o f suspended material, colloids and organic matter • reduction of microbiological fouling • p H adj ustment (e.g. the deposition of silica is minimised by operating at pH >8 or <7) • antiscaling chemicals addition • removal of oxidants in the feed if required. General p re-treatment approaches include:

Journal of the Australian Water Association

• MF or UF membranes, and combinations of conventional and MF/UF,

• chlorine/copper sulphate d osed upstream to reduce biofilm for mation in rhe downstream filters • combined coagulant and single stage dual media filtration with 5 µm cartridge filters as used at Kwinana, WA. Inadequate or no pre-t reatment can result in rap id memb rane fouli n g, excessive cleaning requirements, lower recovery rates, higher operating pressure, sho rter membrane life and lower quality product water.

RO Fouling Research at CSIRO Materials Science and Engineering Membrane fabrication: solution casting, spin casting, d rawing, symmetric and asymmetric membranes.

Membrane characterisation: vario us techniques available includi ng SEM, ED XS, st reaming potential, contact angle, atomic force microscopy, X-ray diffraction , positron annihilatio n lifetime spectroscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, gas ch romatography/mass spectroscopy, UYvisible spectroscopy and inductively coupled plasma spectroscopy.

Novel pre-treatment methods for RO feeds: n ew coagulants, microfiltration and combined micro/nanofiltrat ion technologies.

Optimisation ofscale mitigation strategies: involving the determination of (i) the degree of concentration polarisation usi ng various kinetic modelling methods, and the


technical features

potential of surface crystallisation using thermodynamic modelling and (ii) the scaling kinetics and interactions amongst different foulants including organic and inorganic compounds.

Autopsy offouled membranes from RO plants: as for membrane characterisation. The research is carried out within the CSIRO Flagship Collaboration Fund C luster on advanced memb rane technologies for water treatment char comes under the CSIRO U rban Water Theme (h tt p://www.csiro.au/science/ psu9 . html). The collaborative effort comprises n ine un iversities in partnersh ip with CSI RO membrane research (G ray, 2008).

Conclusions

Ir has been found generally char foulants isolated from RO membranes used for brackish groundwater desalinatio n consist of sim p le scale deposits and, more frequen tly, of composites based on colloids, particulates and biomass chat are d ifficult to remove. The information obtained from membrane cross-sections provides some insights into rhe deposition processes which are important for achieving a more complete understandi ng of rhe fouling mechan isms. T he usual approach

of analysing the top surface of rhe fouling layer or studies which give only the average composition of the surface deposits does nor provide the complete picture. We have fo u nd char NOM and inorganic particulate maccer are absent in the secondary fou ling layer, and there is exclusive growth of aluminium silicates on top of this layer. Work is already underway to identify che nature of chis layer, which, as suggested, could include extracellular polymeric substances. Methods of analysing che undisrupted multi-fouling layer are to be explored so chat we can obtain a complete understand of the foul ing mechan ism.

References Amy, G ., Cho, J., Yoon, Y., Wright, S., Clark, M. M., Mel is, E., Combe, C., Wang, Y., Lucas, P., Lee, Y., Kumar, M. , Howe, K., Kim, K.-S., Pelligrino, J. and Irvine, S. (2001). NOM rejection by, and fouling of, NF and VF membranes. AwwaRF Report, Awwa Research Foundation, Denver. Bolro, B. A. and Tran, T. and Hoang, M. (2008). Pretreatments for seawater reverse osmosis. Water, 35 (2), 105-110. Braghecra, A., OiGiano, F. A., and Ball, W. P. (1997). Nanofilrrarion of natural organic matter: pH and ionic strength effects. J Environ. Eng. 628-640.

Gray, S. (2008) . Research on advanced membrane technologies. Waw; 35 (2), 111113. Gwon, E.-M. , Yu, M.-J. , Oh, H.-K. and Ylee, Y.-H. (2003). Fouling characteristics of NF and RO operated for removal of dissolved matter from groundwater. Water Research 37, 2989-2997. Kumar, M., Adham , S. and Pearce, W. R. (2006). Investigation of seawater reverse osmosis fouling and its relationship to pretreatment type. Environ. Sci. Technol. 40, 2037-2044. Ning, R. (1999). Process chemist ry relevant to the Gulf. Desalination 123, 157-163. Saad, M.A. ( 1992). Biofouling prevention in RO polymeric membrane systems. Desalination 88, 85-105. Tran, T., Bolto, B. A., Gray, S., Hoang, M. and Osrarcevic, E. (2007) . An autopsy study of a fou led reverse osmosis membrane element used in a brackish water treatment plant. Water Research 4 1, 3195-3923.

The Authors

Dr Brian Bolto, Dr Thuy Tran and Dr Manh Hoang (email: brian.bolto@csiro.au; thuy.tran@csiro .au; manh.hoang@csiro.au) work for CSI RO Materials Science and Engineering, Clayton, Victo ria (postal address: P rivate Bag 33, Clayton MDC, Vic 3169) .


Al AND THE WATER INDUSTRY THE NEXT WAVE P Radcliffe Ar rhe ru m of rhe last century, a major shift in rhe way business is conducted was underway in rhe world-the shift was outsourcing. T here is now another movement similar to outsou rcing which is fu rther increasing rhe efficiency of co mpan ies - rhe application of artificial intelligence to enhance and support decision makers to do th ings faster, better and cheaper

algorithms, ant colony optimisation, particle swarm optimisation and neural networks are enhancing rhe pl anning, design and operations of water systems like never before. T he use of generic algori thms alone has enhanced the plann ing of new water systems by simultaneously improving rhe hydraulics, and rhus levels of customer service, while reducing cost. Savings in the order of 15% and more are typical in most instances where generic algorith ms have been applied in rhe planni ng process of a proj ect.

Artificial Intelligence in the Water Sector As rhe water industry continues to search fo r ever more efficient ways to use water, the nature of rhe desi gn problems is becoming more complex. Water urili ries are now looking to integrate water, wastewater, recycl ed water and even storm water into a single netwo rk to minimise wastage and imp rove security of supply. T his increased complexity is fu rther inAuencing rhe need ro incorporate AI into all aspects of water system design and operations. New ways of working with water such as sewer mi ning, desalination, aq uifer storage and recovery (ASR), and giant transport p ipelines are being developed and constructed around rhe world. How can a water utility choose what to build, where infrast ructu re should go and how large to b uild a system? T he number of permutations of how rhis jigsaw can

possibly fi r rogerher is end less. This is where the use of AI is significant in developing the optimal solution. W hile a human mind can use engineering judgement to do a good job and arrive at a solu tion, the engineer is still limited to only being able to carefull y analyse relatively few possi bilities in rhe rime available to arrive at a solution. In contrast, software that utilises AI can work 24 hours a day across multip le co mpu ters at much less cost than a human engineer and with very few complaints! And rhe results speak for themselves. W hen applied to the water industry, rhe di ffere nt fo rms of AI such as generic

Table 1. Identified savi ngs on project plans usi ng genetic algorithm optimisation. Client

Son Diego, CA, USA Reno-Sparks, NV, USA Gold Coast, Qld, AU Wimmero M. , VIC. AU Los Vegas Vo lley, NV.USA London, UK Ft.Collins-Loveland, CO, USA Adelaide, SA, AU Ashford, Kent, UK North Melbourne, VIC, AU Providence RI, USA South East Melb. VIC, AU

l 00 JUNE 2008

Water

Original Cost Manual Method

Optimatics Genetic Algorithm

$55.0m $26.0m

$35.3m $17.0m $17.Bm $1 l.0m $7.4m £6.9m $3.0m $1.lm

$29.5m $14.3m $9. lm £7. 2m $5.9m $2.2m £57.5m $147m $60.0m $37m

£49.9m $8l m $5 l.5m $3 l m

Journal of the Australian Water Association

Savings

$20m (36%) $9.0m (30%) $1 l.7m (40%) $3.3m (23%) $l.7m (19%) £l.3m (16%) $2.9m (49%) $1.l m (50%) £7.6m (13%) $66m (45%) $8.5m (15%) $6m (14%)

Table l is a list of water and wastewater project plans that were initially devel oped manually by a modeller using engineering judgement and a traditional simulation model. T he project plans were then independently developed using a generic algorithm approach rhar resulted in significant cost savings. Ir is notewo rthy rhar on all of these proj ects, rhe levels of service provided by the system also improved so there was no co mpromise on quality. Wi ll this spell the end of the Engineer? T he answer to this question is a fi rm 'No'. This is because the pace of change is also increasing and engineers today must manage fa r more projects in less time rhan ever befo re. T here will still be plenty of jobs fo r you ng creative engineers and those with experience who know how to do rhe job right. T he AI approach, in fac t, offers significant benefits to today's engineers and clients.

Integration of Man and Machine Water planning specialists today provide adviso ry roles to water aurhoriries worldwide. Rather than see a replacement of these specialists with adoption of AI, we are going to see an integration of rhe ideas, experience and creariviry of these specialists with the processing and model ling power of tomorrow's computers and AI. This will

Expanding the capacity ofyour professional staff.


technical features

skills shortage happen in the fo llowing way. O nce areas o f a warer business have been rargered for improvement, the current state will be modelled and the desired objectives will be determined. Experienced consultants will then be called upon to recommend solution op tions to chis business objective. Each solution optio n will be inp ur into rhe "intelligent model" along with the associated data such as cost of infrastructure, impact on the system and the environment. In this way numerous ideas can be rigorously reseed and optimised against the performance requirements quickly and efficiently to give accurate feedback to the engineer about the benefits and costs of each. T he platform also allows all parries whether they are planners, operators, politicians or finance people to have a say in the constraints and rules that rhe optimisation process is working to satisfy. T his allows for transparency of results, "buy in" fro m all parries and a closer collaboration between chem.

Al in Operations The need to incorporate AI is also important in the area of wate r system operations where decisions need to be made quickly, accurately and reliably. Wirh rhe risi ng cost of power, labour and maintenance, u til ities need to improve the efficiency and effect iveness o f already established infrastructure. Tech nologies such as demand prediction, pressure reduction, pump control and water quality control need to be continuously improved so chat power usage can be minimised, rhe life of ex isting assets be extended, and, securi ty of su pply is maintained. AI is able to p rovide rhe greater level of control that is necessary fo r op timising system ope rations. Imagine an operations model char gradually adapts itself to the aging of pipes, changing weather predictions and various day to day incidents (planned and u nplanned) occurring in a system. An intelligent model char can recommend when assets need to be replaced, when, where and how much water to pump, and also predict when an emergency event is likely. A model that au tomatically springs into action when an emergency incident does occur, providing immediate derails to rhe operators of what the symp toms are, what the most probable cause is and rhe recommended course of action. The id ea is nor to remove operators fro m operations activities, bur to greatly enhance the effectiveness of the operators.

The Skills Shortage T he answer to skills shortage may nor be to train and hire more skilled staff, which is a huge challenge. A better solution is to provide staff wirh more powerful decision support systems. Ar present, a large proportion of an engineer's rime is typically spent o n rhe technical "grunt" work, in particular "number crunching".

By incorporating rhe use of AI to more effectively accomplish the laborious casks, an engineer is freed up to work at a "higher plane" on a given project and to attend to even more projects. Employee satisfaction also increases as the engineer is called upo n to tackle more creative aspects of a project rather than getting bogged down in the tedious aspects of the tech nical work. This improves their effectiveness ar work wh ile

-~~ -~

creating a more rewarding career resulting in higher employee retention.

Conclusion The convergence of increased computer power, AI technology and robust wireless communications is paving rhe way to establish changes in every industry, to become more effective and efficient than ever before. These changes have paved the way for outsourcing and are now doing the same fo r the automation of work by compurers runni ng powerful new intell igent programs. The gains in productivity for engineers in rhe water and wasrewarer industry will flow on to customers bringing lower costs and h igher levels o f service. T hose engineers directly utilisi ng AI technology will be empowered to ful fil their highest potential in rhe innovative management of our water systems.

The Author Peter Radcliffe is an optimisation specialist with rhe company O p timatics. Optimatics are world leaders in rhe application of artificial intelligence to the water industry. For more information contact peter. radclijfe@optimatics.com

QUALITY ASSURED ENGINEERED PRODUCTS

Designer a nd ma nufacturer of hig h efficiency, low speed floating and fixed surface aerators from 3 kW to 220 kW with an unmatched 5 year, unlimited hours guarantee. By-Jas offers flexible financing and delivery solutions including rental , purchase and fully ma intained operating leases. Ring now for a current stock list. Other products in our range incl ude settling tanks (12 designs), packag ed sewage a nd water treatment plants, reuse filters and clarifiers to Class B and Class A standard.

For more information, contact: By¡Jas Engineering Pty Ltd PO BOX 424, HASTINGS VIC 3915 Tel: (03) 5979 1096 Fax: (03) 5979 1524

Journal of the Australia n Water Association Water JUNE 2008 10 1


POWER MANAGEMENT IN PRODUCTION AND PROCESS AUTOMATION Siemens has added che function power management to the range of functions of its Simacic PCS 7 control system and Simatic WinCC visualisation system for the production and process industry. The power management add-ons, called Simacic PCS 7 powerrate and Simatic W in CC powerrate, provide a unifo rm power management solution for all branches of industry. T he user is able to locate savings potential, draw co nclusions regarding che power behaviour of d ifferent operating units and obtain information on the stacus of the plant and che degree of u tilisation.

Water Business aims to keep readers alert co business news and new produce releases within the water sector. Media releases should b e emailed co Brian Raulc at b rian.raul c@halledic.com.au or T el (03) 8534 5014.

AWA wishes co advise readers chat Water Bwiness information is supplied by third parties and as such, AWA is not responsible fo r che accuracy, or oth erwise, of the information submitted. of che Year' ac che Global Water Awards in Londo n lase week. T hiess/Black and Veatch in an Alliance with the Queensland Department of Infrastructure received che award wh ich recognises che water or wastewater p roject, commissio ned in 2007, that represents the most significant contribution to water technology and environmental protection.

The ind ividual fu nctions such as measured value acquisition and process ing, cost centre management and load management are implemented by means of ready-made S7 modules, faceplates and Excel macros. The operator can therefore use their familiar system environment for comprehensive data management and visualisation. The power management add-ons obtain the power values from switching, protectio n and measuring devices such as che Sentron PAC320 0 multifunctional measuring instrument, wh ich precisely measures che characteristic values and power values of loads in industrial and pu rpose-built buildings.

For more information, please contact Siemens on 131 773.

BUNDAMBA PLANS GLOBAL WATER AWARD The Bundamba Advanced Water T reacment Plant (AWTP) was named 'Water Project

The Bundamba plan t is already helping to cake pressure off South East Queensland's water supply with rhe capacity to recycle up to 66 mega litres of water per day.

John Willmott, T hiess Executive Manager fo r Infrastructure Queensland and Alliance Leadership Team member, said the award is a testament co che o utstandi ng commitment of the T h iess/Black and Veatch team to deliver a world-class project. "Being nominated and recognised by the industry makes ch is award important as our international peers have recogn ised the qual ity of our work and the exceptional circu mstances we were operating under to deliver chis project in record rime," said Mr Willmore. The Bundamba AWTP was one of four shore listed for chis award, rhe ochers also shore listed were Lake Pleasant Water Treat ment Plan in Arizona, Orange Country Groundwater Replenishment Project in California and Plazxow 11 Treatment Plane in Poland.

Gus Atmeh, Bundamba AWTP Pro ject Director, says the pro ject showcases the effective use of world class technology including the 18-inch reve rse osmosis membrane (pictured here). An A ustra lian first, th e new technology was origi na lly developed in the Un ited States and has not been used outsi de the US to thi s sca le anywhere el se in the world.

BENTLEY'S SOFTWARE FOR WATER AND WASTEWATER PROFESSIONALS Bentley's Haestad Methods product li ne of software provides water professionals with advanced engineering cools to plan, design, maintain, analyse, manage, and operate water d istribution supp ly, mun icipal sanitary sewers, urban scormwater collection, and roadway and civil sire drainage. Bentley is distinct among software p roviders in char it offers: â&#x20AC;˘ A comprehensive software portfolio chat is m u ltidisciplinary, just like users' projects, and incl udes (among many ocher solutions and p roducts) software for:

T he Bu ndamba AWTP is a core component of rhe Queensland Government's $2 .4 billio n Western Corridor Recycled Water (WCRW) Project. Ir is the first of 3 AWTPs to be constructed under rhe largest recycled water scheme in Australia.

- water distribution analysis and design - transient analysis - sanitary and comb ined sewer analysis and design - fu lly dynamic stormwarer analysis and design - culvert and hydraulic calculators

WaterGEMSÂŽVB XM Edition COMPREHENSIVE AND EASY TO USE WATER MODELLING SOFTWARE Bentley WaterGEMS VS XM Edition, for water distribution modelling, comes equipped with everything engineers need in a flexible multi-platform environment, from fire flow and water quality simulations, to criticality and energy cost analysis, to flushing and water leakage analysis. For more information, see the inside front cover of the June issue of Water Joumal, visit www.bentley.com/A WA, e-mail anz.marketing@bentley.com, or call +61 (0)3 9699 8699.

l 02 JUNE 2008 Water

Journal of the Australian Water Association

Profile for australianwater

Water Journal June 2008  

Water Journal June 2008