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Volume 3 0 No 5 August 2003 Journal of t he Australian Water Association

Editorial Board F R B isho p, C hairman

l3 N Anderson, W J Dulfer, G Finke, G F111Jayso11, GA Holder, B Labza, M Muntisov, P Nadebaum,J D Parker, F R oddick, G R yan,

OPINION

S Gray

2

AWWA and Climate Change; Action and Fragmentation; My Point of View, Sustainability and WSAA's Five Year Forward Look, J La n gford

•, Wnrer is a refereed journal. This symbol indicates that a paper has been refereed.

Submissions Instructions for authors can be found on page 2 of this journal. Submissions accepted at: www.awa.asn .au/pu blications/

Managing Editor

ASSOCIATION ACTIVITIES 6

Including AIWA Report

PROFESSIONAL DEVELOPMENT 10 Details of courses, classes and other upcoming water events

Peter Stirling

NEWS BYTES

Technical Editor

14 Featuring selected highlights from the AWA email News

EA (B o b) Swinto n 4 Pleasant View Cres, Wheelers Hill Vic 3 I50 Tel/Fax (03) 9560 4752 Email: bswinton@bigpond.net.au

CROSSCURRENT

Water Production H allma rk E ditio ns PO Box 84, Hampton, Vic 3188 Level I, 99 Bay Street, Brighton, Vic 3186 Tel (03) 9530 8900 Fax (03) 9530 8911 Email: hallmark@halledit.com.au G raphic desig n: Mitz i M a nn

Water Advertising N a tional Sale s Manager: Brian R ault Tel (03) 9530 8900 Fax (03) 9530 8911 Mobile 0411 354 050 Emai l: brault@halled it.com.au

20 Earth Systems Launches the Australian Water Map; South East Asian Water Mission Visits Western Australia; Good News for Catchment Managers, Power Up Sets the Pace in Careers Media

CONFERENCE REPORT 23 AWA-IWA Specialty Conference: Chemicals of Concern in Water, D Wies ne r

SUSTAINABILITY FEATURE 25 FORECASTING AND BACKCASTING FOR SUSTAINABLE URBAN WATER FUTURES Two approaches to predicling the future C Mitchell, S Whi te

34 WHAT IS A SUSTAINABLE WATER UTILITY? Aresearch program to help management

Water (ISSN 0310 • 0367) is pu blished eight times a year in the months of February, March, May, June, August, September. November and D ecember.

V Uhlmann

36

Australian Water Association

.. URBAN DOMESTIC WATER TANKS: LIFE CYCLE ASSESSMENT Plastic tanks save water bul are expensive T Gra n t, M Ballmann

PO Box 388, Artannon, NSW 1570 Tel +6 l 2 9413 1288 Fax: (02) 941 3 1047

WATER REUSE FEATURE

Email: info@awa.asn.au A.BN 78 096 035 773

42 L-- THE HAWKESBURY WATER REUSE SCHEME University of Western Sydney integrates effluent and stormwater

Federal President Rod Lehma nn

Executive Director

AWA

~

AUSTRALI AN WATER ASSOCIATION

C hris D avis Australian Water Association (A WA) assumes no responsibility for opinions or statements of facts expressed by contributors or advertisers. Editorials do not necessarily represent official AW A policy. Advertisements are included as an information service to readers and arc reviewed before publication to ensure relevance to the water environment and objectives of AWA. All material in Wnrer is copyright and sho uld not be reproduced wholly or in part without the written pern1ission of the Managing Editor.

Subscriptions Water is sent to all AWA members eight times a year. It is also available via subscription.

Visit the ASIIOCilaUon and access news, calendars, bookshop and Oll9r 100 pages of lnfonnatlon at

C A Booth, R Attwa te r, C Derry, B Simmons

45

, ATTITUDES TO RECLAIMED WATER FOR DOMESTIC USE: PART 1. AGE Young people are marginally more supportive J M cKay, A Hurlima nn

SO MANAGEMENT PROGRAM HELPS BUSINESSES SAVE WATER IN WA The Water Corporation partners customers M Yiskovich, S Moulder

53 KWINANA WATER RECLAMATION PLANT Membrane technology enables large-scale reuse T Walk er

WASTEWATER 57

~

BIOSOLIDS TO LAND: INTERNATIONAL REGULATIONS · PART II: PATHOGENS Comparing Australian approaches with USA and Europe H Reid , A Savage

OUR COVER: A South A 11stralia11 co1111111 rnity is to have reclai111ed 111aste111ater and stormwater plumbed into their houses for toiletjlushi11g as well as garde11i11g water later tit is year. A study exploring responses discovered that as tlte use of the reclaimed water becomes n1ore perso11al, support decreases, bHt 110/ so 1nuc/1 i11 yo1111ger people. See article 011 page 45 . WATER AUGUST 2003

1


FROM

THE

PRESIDENT

AWWA AND CLIMATE CHANGE I was pleased to be able to attend the American Water Works Association 's annual conference in Anaheim, California, in June, together with our CEO , Chris Davis. We were made to feel ve1y welcome by our US colleagues and it was an exciting event overall. One of the main points emerging in Anaheim, from my point of view, was the discussion on disinfec ti o n , disinfec ti o n b y- produ cts (particularly o rganic nitrogen species nitrosamines) and xenobiotics (the prefix xeno- means 'stra nge') generally. Xenobiotics is a term which embraces both disinfectio n by-p rodu cts and wastewater derived contaminants such as endocrine disruptors, including pharmaceuticals and NDMA (stick with the acronym - the full name's a mouthful! ). R ecent research in the US has looked at the sources of these contaminants, and their persistence through both wastewater treatment and water treatment processes. There is also some good work being done in Australia in this regard (vide the recent Chemicals of Concern conference) but more work needs to be done to fully understand the implica tio ns of these contaminants and how they best might be remo ved, w here necessary. Organic nitrogen in water has a potential role in the fo rmation of disinfection by-produces, the biostability of raw and treated water

water

Contributions Wanted The Water journal welcomes the submission of papers equi valent to 3,000-4,000 words (allowing for graphics) relating to all areas of the water cycle and water business to be published in the j o urnal. T opical stories of up to 2,000 words may also be accepted. All submissions of papers intended for the main body of the j ournal should be emailed to the T echnical Editor, bswincon@bigpond. net. au, with a copy to the AW A website, www.awa.asn. au/ publications. Shorter news items should be em ailed to news@awa.asn.au and also to the website. A submitted paper will be tabled at a monthly J ournal Committee meeting where, if appropriate, it will be assigned to referees. T heir comments will be passed back to the principal author. If accepted and after any comments have been dealt with, the fi nal paper can be emailed with the text in M S Word but with high resolution graphics (300 dpi tiff, jpg or eps files - Z ip disks or C D-ROMs can be accepted) in separate fiJ es, or hard copy photos and graphics suitable for scanning by the publisher can be mailed to 4 Pleasant View C res, Wheelers H ill, Vic 3 150.

2

WATER AUGUST 2003

Rod Lehmann

and in m embran e fouling. At ou r Chemicals of Concern conference, Dr Richard Bull highlighted the fact chat nitrogen comp ounds now seem to be the chief suspect in carcinogenicity. It seems to me that more research is required to better understand the so urc e and fa te of all xenobiotics. I have noticed in my professional work in Queensland that co mmunity consultations on water recycling, in particular, seem to end up discussing x enobiotics, so the iss ue pervades professional and co mmunity discourse alike. Another of my impressions in Anaheim was that Australia is very welJ regarded fo r the work it's doing with water quality management and asset management. After Anaheim I did a short to ur around the south west of the US and I was struck by the prevalence of wind gen erators. These can apparencly produce 1 megawatt of power per installation. An exp ert noted that wind power could genera te 80 per cent of America's power requirements; but the main impediment was the lack of well-placed links to the national power grid. In the USA, in some regions, power companies pay farmers and graziers a reasonable sum of money for the right to deploy wind generators on their properties. Th is is a win-win outcome. The digression into sustainable energy leads me to the point that Australia does not seem to have embraced the issue of climate change and that th ere may be opportunities for the water industty to look at ways of using alternative renewable energy sources to drive systems. For the water industry, though, an even more critical issue is that of the impact of climate change on w ater resources. A classic case in point is Perth, w here two , step changes in rai nfall (downwards) over the last 30 years has had quite a profound impac t on runoff. A nee

reduction of 15-20% in precipitation has led to an asto unding 42% fall in runoff. Few Australia communities could hope to tolerate such major shifts in water availability. More alarming still is a prediction from the CRC for Catchm.ent H ydrology, which has modelled the likely impacts of cli mate change on runoff, in 28 Australian catchments. The CRC stated that, 'in wet and temperate catchments, the percentage change in runoff is about twice the percentage change in rainfall, whereas in ephemeral catchments with low runoff coefficients the percentage change in runoff can be more than four times the percentage change in rainfall '. In response to alarming statistics like these, the Institute for Sustainable Futures, attached to the University of T echnology in Sydney, has proposed a project titled, Water and Climate Change: Communicating the Impacrs. !SF is looking for partners to support the project financially and/ or inkind. The message is intended to reach the industry and the wider community. We all have a stake in coping with climate change and we should all be part of the debate about how we, individually, corporately and nationally, should be amending our behaviour to reduce our own impact on climate change. I hope AW A will be able to provide at least in-kind support to the ISF project and I commend it co others to consider too. This issue is not going to go away and organ isations neglect it at their peril. Rod Lehmann

THE GUY PARKER AWARD The Award is made to honour the memo1y of Cecil D avid (Guy) Parker, who played a leading role in the formation of the Association, was the fou ndation chairman of the Journal Water, and was a major contributor to research on wastewater treatment in Australia and overseas. On-Line Mo11itoring of R eservoirs fo r Risk Management by Messrs Brookes, Lewis, Linden and Burch has been selected as the best paper published in the Journal fro m May 2002 until to March 2003, and has been awarded the Guy Parker Award. It was published in Volume 29, No 5,. August, 2002. The selection criteria are originality, relevance and presentation. The Award carries a cash prize of $500.


SUSTAINABILITY

FORECASTING AND BACKCASTING FOR SUSTAINABLE URBAN WATER FUTURES C Mitchell, S White Abstract The Australian and international water industry is on the verge of significant change, and a significa nt opportunity to embrace sustainabili ty in its operations. T h e paper shovvs how a combination of fo recasting and backcasting is necessary for p redicting a water service provision model of th e future. Using some real exa111ples, we dem onstrate how actions that pick the low hanging fruit result from fo recasting and how actions that challenge existing ass u mp t io n s r es ul t from backcasting. We show how the applica tion o f these two tools can pay dividends for residential, commercial, and industrial water users.

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Introduction The water industry in Austral ia and in te rnatio nally is on the verge of a signi fica nt move fro m commodity supply to service provisio n. The drivers behind this change include • Total ann ual water sales much lower than forecasted , leading to stagnating u tili ty revenues;, • Increasing interest in holistic thinking; • Increasingly limited access to adequate and affordable water reso urces; • Aging in frastru cture; • In creasingly expensive maintena nce of highly centralised systems; • In creasing treatm ent costs; • Increasingly stringent discharge licences; • In creasing recognitio n of poten tial reso urces in stormwater and sewage nutrients; • R egulatory requ irements for more cost-reflective water system pri cing; • N ew approaches to infrastructure provision; and • Privatisation and competition In this paper we outline how th e m eth ods of forecas ting and backcasting ca n b e h armonized to provi d e a framework fo r taking actions to meet th ese challenges. By way of a series of exa m p l es, w e show h ow such an approach is alrea dy co ntribu ting co chan ging practices.

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Environmental Business Solutions Market Assessment & Marketing Financial & Economic Analysis Feasibility Studies Project Co-ordination Strategic Development Leaders in water recycling, irrigation and more

WATER AUGUST 2003

25


SUSTAINABILITY

Living within our Means If sustainability is about preserving and conserving the resources for future generations then managing for sustainability is about ' living within our means' . When this simple principle of'living within our means' is applied to water resources, we can appreciate the significance and value in moving from 'supply-side thinking' to the approach of 'water service provision The fundamental difference in the two approaches is that the former views managing the demand for water as a commodity supply business whereas the latter approach is focused on providing a broader range of services to meet the wa ter deman d. For a discussion of integrated resource planning as a means of providing water related services and the comparison with supply side planning see Howe and White (1999) , White and Fane (2001) . In th e fo ll owing sec ti ons, forecasting and backcasting are introduced as two tools that can b e used to complement one another to take appropriate actions on th e above strategies. Guiding strategies for urban water systems that would be consistent with ' living within our means' include: • R ecognising the limits of a catchment and the water that is available within it; • Ensuring water use is efficient i.e. use the lowest volume of water necessary to provide a service o r to meet a demand; • Ensuring water use is effective i.e . use the lowest quali ty of water necessary to provide a service; • Ensuring sufficient and appropriate quality flows to our local ecosystems; • Maximising the efficiency of the use of energy and materials to deliver a service; • Investing in new and existing infrastructure consistent with these principles; and • Investing in institutional structures and arrangements w hic h facilitate thes e principles Predicting the Future and Taking Action Planning fo r the future is a core activity of all water businesses. Whilst predicting

26

WATERAUGUST2003

the future is impossible, there are a wide range of techniques for thinking about what might happen, and how we can influence that. In ve1y general tenns, these methods can be categorised as either forecasting or backcasting. Forecasting methods are based on current dominant trends, and therefore tend to describe futures that look similar to th e present. Forecasting methods struggle to anticipate surp1ises and discontinuities. Backcasting, on the other hand, begins by defining a societally preferred future , and th en works backwards to determine alternative feasible physical and behavioural paths connecting the societally preferred futu re with th e present. Thus, the solutions generated by backcasting are independent of current dominant trends. A desirable water service provision model of the future therefore requires the application of both forecasting and backcasting. Forecas ting and backcasting are complementary in planning for the future. W hen thinking about a future incorporating sustainable urban water service provision, forecasting can help identify the actions that produce results in th e short term, and deliver needed marginal changes in how water is used. In other words, forecasting can help pick the low hanging fruits. Having identified short-term measures, it is also important to simultaneously develop scenarios for a societally preferred future, w hich is not limi ted by assumptions of th e present. In other words, a futu re that challenges existing assumptions. Backcasting is a technique that can h elp in this process because it provides a focus on a longer timeframe and delivering step changes in the water business. Thus, together the two techniqu es are necessary and sufficient conditions for sustain able urban water systems. Our view, ill ustrated in Figure 1, is that these two processes inform each other, and so both are necessary, and best implemented in an ongoing iterative approach. C hallenging existing assumptions will generate diffe rent p erspectives, and with a different perspective, we might identify

different low hanging fru it. Identifying and acting on different low hanging fruits changes o ur current position, so the path from our cunent position to the preferred future changes, and so forth. T o make this explicit, think about Australiaville Water, a large urban water utility. Australiaville Water's forecasts show that the security of supply of the existing system will be reduced due to the expected rise in population, long-term rainfall trends, and the need to increase environmental flows. Options that may be proposed include new water supply storages, transferring water from neighbouring catchments or even desalination. At the same time, Australiaville Water might engage in backcasting and challenge its existing assumption that more supply is the only option for meeting the demand. It might do this by evaluating the costs and benefits to the community of investing directly in the improvement of water efficiency by its customers and through reducing system losses. This process, known as least cost planning or integrated resource planning, begins with end-use analysis, and asks w hether there are opportunities for reducing demand which have a lower cost per unit volume than equivalent supply augmentation options. In most cases, reducing demand by installing water efficient showerheads, taps, toilets, washing machines, cooling towers and urinals is the cheapest, fas test, and most sustainable way to obtain new wate r for increasing population or environmental needs. In the sections that follow, we demonstrate the kinds of actions that result from forecasting and backcasting techniques.

Short-Term Actions from Forecasting Forecasting helps in identifying actions that pick the low hanging fruit. These actions are easy to do now, more or less within the existing urban water system, and will pay sustainabili ty dividends in both the short and long term . These actions are aimed at making the most of the system as it stands, and include a focus o n , for example, water efficiency.


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For further information, please contact our Business Development team - David Love, Michelle Morris or Karen Shaw on ph: (61-2) 8572 0300 or visit our website at: www.veoliawater.com.au


SUSTAINABILITY

Improved water effi cien cy is often associated wi th red u ced e n e r gy cons umpti o n and greenhouse gas emissions as well as reduced costs for wa ter treatment, sewage transport and treatment , and r e-distrib ution or discharge. We see a hierarchy within low hanging opportunities: 1. Demand management: Maximise water efficiency and implement source control 2. Water quality cascade: Match required water quality with water quality supplied D emand management means looking at what our customers use water for (end uses) and determining w hether the same service could be provided using less water. The classic example here is the installation of water efficient showerheads and tap regulators that can save between 23 and 35 kL/hh/year in large scale programs. The USA, for example has had mandatory performance standards for showerheads and many other water using fixtures, since 1994. Australian initiatives in this area have led to moves fo r mandatory labelling (Day and White 2002, Sarac, Day, and White 2002) .

Implementing demand management first , opens up more opportunities for better matches between the quality of water required for specific end uses, and the level of treatm ent needed and therefore quali ty of water supplied. For example, a concept study carried out by the Institu te fo r Sustainable Futures for Sydney Water's n ew co r porate headquarters showed that the bu ilding could, in principle, have accommodated up to 1,000 people using only rainwater captured on site as the water source. This was possible through significant efficiency improvements by low water use dual flush toilets, waterless urinals, sensor-operated high efficiency taps in hand-basins, and water efficient showerheads, and, most significantly, treatment and reuse of efiluent and the use of ground source heat pumps rather t han cooling towers (Chanan et al 2003). In its new building sustainability rating tool, BASIX, PlanningNSW will provide a performance based scoring system based on the reduction of demand for water through implementing water efficiency and through applying the

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WATER AUGUST 2003

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water quality cascade and implementing source substitu tion (see http:/ /www. planning.nsw.gov.au/ for details). T he most useful fea tures of this tool are firstly that it g ives d evelop ers, b u ilders, plum.hers, home renovators, and consent authorities a consistent set of figures to work from, and secondly, it enables consistent ranking of different water saving opportu nities. Similarly, a new residen ti al, commercial, and public space development at Kogarah Town Square in Sydney implemented the principles of demand management and the water quality cascade . W ith the objective of improving stormwater management and reducing water use, rainwater from the site is collected and used for toilet flushing and landscape water use (Jha et al., 2001). An example of the potential for improved water efficiency within the industrial sector is provided by our recent experience in central Queensland. In this region, large industrial customers have historically been subj ect to long term contracts w ith little, if any, incentive to improve water efficiency . R ecent droughts have meant that allocations have been reduced and restrictions brought into force . Most industries met 10% restrictions with minor changes in practice, very little or no capital investment, and often reductions in operating costs. R eductio ns in demand of up to 50% are being achieved with capital investment 111 improved processes.

Long Term Actions from Backcasting Backcasting with its longer-term approach results in actions that challenge existing assumptions. Existing assumptions must first be identified before they can be chall en ged. I dentifying assumptions behind business-as-usual requires us to step back a little, and see w hat it is we are taking for granted in our decisions. A starting point here could be the assumption that having a single pipe supplying one quality of wa ter for all end uses is the best option. We could start by asking the question 'what do we mean by 'best'?'. D o we mean 'cheapest'? And by cheapest, do we mean 'lowest capital cost'? And by lowest capital cost, do we mean 'lowest capital cost for the portion of the system for w hich we have to pay'? In a recent study for Sydney Water, we developed a series of concepcual servicing plans for a greenfield estate in Sydney's southwest with approximately


aste not, want not. The Water Corporation of Western Australia looks at wastewater as not such a waste after all. A lthough a major player in WA's wastewater industry for many years, recycling has only been a pplied in rural areas. Currently 4 1% of wastewater is reused in 42 reuse schemes, including irrigating golf courses, playing fields, parks, woodlots and some horticultural uses. Now, in an effort to reduce pressure on water supplies in the city, the Water Corporation is looking at doing the same in th e metropolitan area - where only 3% of wastewater is currently being recycled. Given that the residents of Perth produce 280 million litres of wastewater every day, over I 03GL per annum, turn ing wastewater into a valuable resource rather than it just going to waste makes absolute sense. The Western Australian Government State Water Strategy (derived from statewide community forums and the State Water Symposium) has set a target of 20% reuse of treated wastewater state-wide, to

Thanks to the Water Corporation, at least UWA Sports Park is environmentally friend ly.

be achieved by 20 12. One of the first steps towards meeting

by the Water Corporation's new Water

The Water Corporation's environmental

the wastewater reuse target is the

Cycle Project Team. This multi-disciplinary

commitment does not stop at wastewater

irrigation of the University of Western

team has been formu lated to work with

reuse. The Corporation takes a 'total water

Australia's (UWA) Sports Park with

all Co r poration sectors, as we ll as

cycle management' approach to see the

treated wastewater from September 2003.

government agencies, stakeholders a nd

business as supply, wastewater and storm

The treated wastewater will contain a

customers to help make WA Austral ia's

water col lection, and treatment and

most water efficient community.

recovery, return ing to supply.

variety of nutrients and minerals that will hel p reduce the amount of fertil iser needed to keep the park green. T he UWA Sports Park Irrigation project is just one of the new projects set up

~AND WCOR1101

Another target of the Water Cycle Project Team is to achieve ISSkl per capita per annum consumption for the Integrated Water Supply Scheme by 20 12.

www.watercorporation.com.au


SUSTAINABILITY

12,000 lots. The plans va ried from business as usual (dep endence on highly ce ntra lised off-estate water supply , wastewater treatment and discharge) through estate and neighbourhood scale technologies, to all otment scal e technologies. Costs were assumed to include eve1ything necessary to supply the service. All off-estate infrastructure was appropriately pro-rated, and on-estate costs included distribution and supply to the house, rather than to the property boundary. In this joint project of the Institute for Sustainable Futures and CS IRO Urban Water, we showed chat the system boundary used to assess the costs significantly influences the comparative capital costs for vastly differing systems. Instead of breaking up the capital costs for servicing a new subdivisions according to who normally pays (e.g. the water utility is responsible for delivering bulk water and removing bulk sewage and charges the developer a headworks contribution, the developer is responsible for all infrastructure from the boundary of the estate to the boundary of an individual property, and the home buyer is responsible for the infrastructure within their property), we included all the pro-rated costs of all the infrastructure necessa1y to supply the service, regardless of the location of the infrastructure. O n this basis, annualised capitalised costs fo r all options varied by less than 10% (i.e. less than the likely error in the cost estimates). Another common assumption is that water, sewage, and stormwater systems should be considered and planned for separately. Thinking in terms of a total water cycle can enable quite different

water

FUTURE MAJOR FEATURES NOVEMBER

Irrigation, Asset Management, Economics

DECEMBER

Catchment Management, Hydrology, Stormwater

FEBRUARY

30

Disinfection Chemicals of Concern

WATER AUGUST 2003

solutions. For example, in a greenfield residential development in Melbourne's northern o utskirts, wate r effic iency assumptions have reduced projected demand of internal residential use by 45 Li p i d. Further reductions through source substitution enabled by water cycle thinking include using rainwater for the hot water supply (44 L i pi d) and reclai med water for toilet flushing (23 Lipi d) and garden watering (33 Lipid). Overall, this gives a 70% reduction on demand from the reticulated water system. One of the most influential applications of the water quality cascade that also involves challenging existing assumptions is to replace a high quality water stream with no water stream at all. In other words, to think in terms of providing a service rather than providing water. For example, in our central Queensland study, approximately 80% of the raw water demand comes from industry and approximately 80% ofindumy's demand is for cooling. More than half of this cooling demand is from coal-fired baseload power stations in a differen t catchment. Like the new power station at Milmerran in Queensland, these power stations could instead be air-cooled. Taking a total resource cost approach, the levelised cost (Howe and W hite, (1999), Fane, Robinson, and W hite (2002)) of converting to air cooling, and making the limited raw water available for uses for which there is no feasible substitute, appears to be roughly similar to the cost of augmenting supply by either desalination or a pipeline from another catchment.

Conclusion The Australian and international water industry is on the verge of significant change, and a significant opportunity to embrace sustainability in its operations. We have show n how a combination of forecasting and backcasting is necessary for predicting a water service provision model of the future. These two processes inform each other, and so both are necessary, and best implemented in an ongoing iterative approach to make progress cowards sustainable water service provision.

The Authors Dr C ynt h ia Mit ch el l (Cynthia.Mitchell@ucs.edu.au) is a Senior Research Fellow and Professor Stuart White (Stuart.White@uts.edu.au) is the Director of the Institute for Sustainable Futures .. Phone (02) 9209 4350. The

Institute for Sustainable Futures (ISF) is a flagship research centre at the University of T echnology, Sydney. In designing workable solutions to real world problems, we consider the economic, environmental and social dimensions, we select projects based on their ability to create change towards sustainability in the areas encompassing urban infrastructure namely water, energy, building design, urban forms and transport. T he Institute is known nationally and internationally fo r its work on water conservation and least cost planning in the water indust1y. Some of our recent achievements include. • A Banksia Award for Your Home, a compre h ensive national g uid e to sustainable home design that was w ritten by !SF for the Australian Greenhouse Office. • A lead role in Efficient 2003, an international conference on the efficient use and management of water fo r urban supply held in Spain from 2-4 April 2003

References Chanan V, White S, H owe C. andjha M. (2003)

S11stai11ability i11 Co111111ercial Q[fice B11ildi11gs: B/11epri11ts for S11stai11able vVater M111111ge111e11t, Proceedings of OzWate r Conference April 2003, Perth Day D and White S (2002), Mi11i11111111 Perfor1111111ce

St1111dards for Sltower/1eads i11 Australia • the Bwef,rs 1111d 1he Barriers Proceedings of the International Water Association Congress, Melbourne, April 2002. Fane S, Robinson J and White S (2002) Th e use

of /eve!ised cost i11 co111pari11g supply a11d de111a11d side optio11s. Proceedings of the International Water Association Congress, Melbourne, April 2002 Howe C and White S (1999), Integrated Resource Planning fo r Water and Waste Wa ter: Syd n ey Case Studies, Water Inten1atio11al, 24, No 4. 356-362. Jha M, Mauritz M, Smith P and Fane S (2001)

lntegrnted water management system in an urban redevelop111e11 t in Sydney. In te rn ational Ecological Engineering Conference, Lincoln University, Canterbu1y, New Zealand, 2629 November 2001. P arliamentary Co mmi ssioner on t he Environment (2000) Ageing Pipes and Murky

Waters, Urban water system issues for the 21st centW}', June 2000, Office of the Parliamenta1y

Commissioner for the Environment (T e K aitiaki Taiao a Te Whare Paremata), Wellington Sarac K, Day D and White S (2002), What are

we Savi11g Anyway: The R esults of Three Water Demand /\llanagement Programs in NSW. Proceedings of the International Water Association Congress, Melbourne, April 2002. White S and Fane S (2001), Designing Cost Effective Water Demand Management Programs in Australia, vV11ter Science and Tec!1110/ogy, 46. Issue 6-7.


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SUSTAINABILITY

WHAT IS A SUSTAINABLE WATER UTILITY? V Uhlmann Introduction Despite the progressive impacts o f COAG water reforms in Australia, a recent Senate Inquiry into Australia's urban water management fo u nd that consumption levels continue co be unsustainable wh ile at the same time consumers are paying among the lowest prices in the world for the comm odity.

Research program

Development of the definition of a sustainable water utility Over time the definition of sustain ability has moved from the simple B runcland ' intergen erati ona l equi ty' cowards an all-encompassing view based on the triple bottom line, balancing social, economic and environmental needs. T his multi-objective and multi-disciplinary approach is exemplified in the following defi nitio ns of sustainable water systems:

The Sustainable Water Utilities Project "chose designed and managed co fully is part of doctoral researc h being contribute to the objectives of society now and in the future while maintaining conducted at the Advanced Wastewater th eir ecological, environm enta l and Man agem ent Centre, Uni vers ity of hydrological integriry" (ASCE 1998; Queensland, Australia and aims to: United Nations 1999) • Develop an affordable, practical & user"A sustainable urban water system fri endly tool fo r use by water u tilities in should over a long time perspective assessing and improving their sustainprovide required services while protecting ability. human health and the environment, with • Add ress the followi n g research a minimum use of scarce resources." questions: (Lundin 1999 p.25) - H ow sustainable can an urban water These definitions, however, do not utility be without a total catchment provide sufficient detail on which a water focus? Can scormwacer be ignored by utility can act. Fortunately, Gleick (2000) a water uti lity in managing its sustaindisaggregated the new water paradigm ability? into the followi ng principles, which he - Are sustainability benchmarks needed, believes reflect environmental, social and and if so how could they be developed economic values: and applied? 1. Meet basic human needs for water for The research program is divided into drinking and sanitation; three stages: 2 . Meet basic ecosystem n eeds; 1. D eve lopme n t of sus t ainab ility 3. Give higher prioriry to non-structural management tool alternatives to meet demand; 2 . Water utility input 4. Apply economic principles more 3. Case studies co trial and refine cool frequently and reliably to water use and Components of the sustainabili ty management; management tool will include: 5. New supply systems must be flex ible • Definition of a sustainable water u tility and efficient; • Sustainability assessment and decision6. All stakeholders should be involved in making seeps decision-making . • Selection criteria for sustainabili ty The contributions of a number of ocher indicators aucnorities together form a broad approach • Core sec of sustainability indicators - co sustainabiliry w hich has come co be known as integrated water resource • Selection of multi-criteria analysis m anagement (IWRM): software for choosing between sustainability options 1. A holistic view of water resources, which focuses on whole-of-catchment Following an exhaustive literature and total water cycle management survey, a draft cool was prepared and (TWCM). feedback sought from a sample of twenty utilities of varying sizes in coastal and 2. Acknowledgement of multiple and inland locations via workshops/meetings competing social and economic as well as held across Queensland in February 2003. environmental objectives, and the need

34

WATER AUGUST 2003

to balance th ese throug h syste m atic tradeoffs 3. Acknowledgement of externalities and transparen t internalization of these factors 4. Use of lease cost plan ning approaches (LCP). 5. Collaborati on between responsible agencies and w ith the community. 6. U se of adaptive and flexible solu tio ns to address complexity and uncertainty in plan ning environm ent. IWRM can then be applied co define a sustainable urban water utility by its goals or desired outcomes, and its objectives and strategies. It is argued that su ch an outcomes-focused or performance-based definition best represents a susta inability management framework for water utilities, with performance systematically measured agains t i ts goa ls and object ives. Sustainability indicators muse represent a thorough understanding of the urban water system so it is important to d evelop the right conceptual fram ework A draft definition was developed based on the above goals, objectives and strategies, and comm ent sought from the sample of water utilities. Following are the main points agreed to by the majority of participating water u tilicies/ councils: 1. There is interest by water u tilities in assessing and improving sustainability . .However, in most cases it has not yet progressed very far. Larger, betterresou rced utilities are more awa re and interested, however the political drivers co pursue sustainability are often absent. 2. A multi-disciplinary approach to sustainability for water utiliti es is largely supported. No additio ns were made to the main contributing fields of economics, engineering, environmental science, social sciences and sustainability. In a couple of cases, social sciences was seen as being a less important contributor. 3. T h e draft defin ition of a sustainable w ater utility is largely supported. The triple bottom line approach was agreed, with wording changes to some goals and objectives. It is in the Strategies employed by a sustainable water utility that most significant refinements occurred:


SUSTAINABILITY

• In some cases, demand-side (least-cost pl anning) approaches were n ot w ell known. P ricing and consu mptio n targets were seen as key by some and simplisti c by others. • Public participation in planning and decision- making is supported in most cases, but the mechanism for participation n eeds to ensure efficient and effective in pu t as it is perceived as a difficu lt area to m a n age . Part ic ipation was not s upport e d in a fe w c ases, with d isagreem ent that it forms an integral compo nent of sustainable water resource management. • T WCM is an important elem ent of sustainability, in principle, bu t difficult to achi eve fo r two reasons. Firstly, most water utilities in Q ueensland do not own or have a mandate to manage the majori ty of the sources with in th e water cycle (s urfa ce wat e r , grou n dw at er a n d st o r m wa t e r) . I t w as a r g u e d t h a t st o rm w at e r, t hou g h a s ignifi c ant component of the water cycle, should not be ignored; bu t also that it cann ot b e in co rporated easily w ithin the current institutional arrangements. Th is is because where stormwater enters council infrastru cture, it is usually th e respo nsibili ty of a separate roads and drain age section o f the co uncil. H o w ever, water sensitive urban design (o r rainwater tanks by th emselves) is supported for the wh ole of th e shire, or on a proj ect by project basis. A second difficulty arises in T WCM because water utility/co unci l bo undaries rarely coincide w ith catchment, and th erefo re water cycle, boundaries. T h ey therefore believe they do no t have the ability to m anage the entire water cycle even if it became a utility responsibility, unless a regional planning body (of some kind) ove rsaw a coordinated utility approach. • Externalities are not seen as th e responsibility of water utilities. Most w ater utilities are undertaking full- cost pricing, passing on fu lly the price charged by their bulk w ater supplier to th eir consumers. T he bulk water supp li er is viewed as the agency that needs to address unaccountedfor ecological services via catchment ma n agem e n t programs. Any pric e increases may need to be able to be transparently justified to the pricing regulato r.

the practicaliti es of total water cycle managem ent and th e fu ll recogni tion of u tility-related externalities re ma ini ng significant points of difficulty . It is important to gain suppo rt from r eg u la tors fo r an y s u sta inab i l i t y man agement approach developed for water utilities. Performance reporting is already re quired b y e n viro nm e ntal protection , natural resource managem ent, health and pLicing regulato rs and requested by other governm ent o r industry bodies such as the WSAA, AW A and in some cases voluntarily by the NP I. M ost req uire use of di fferent indicator sets. If a core set of sustainability indicators collated and improved these existin g indicato rs, this wo uld avoid duplication of effort bu t wo u ld need regulator support b efo re it wo uld be taken up by utilities. Assuming this could be achieved, the critica l requiremen t remains ensuri ng the agreed core indicator set m easures the goals and o bjectives of the definition.

Next steps In the next p hase of the research, two case study trials o f th e sustainability management tool are proposed - one with Go ld C o ast Wat e r in So uth-Ea st

The Author Vikki Uhlmann .is a P hD researcher at the Adva nced Wastewater Managem ent Centre, U niversity of Queensland . E mai l Vik ki .Uhlman n @ bigpond.co m . H er supervisors are Dr Jurg Keller, D r Paul Lant, an d Andrew Speers (CS IRO).

Selected References ASCE ( l 998). Sustainability criteria for water resource systems. R.esto n, Virginia, ASCE developme nt. " ~Valer llltel'llntio11nl 25 (1): 127- 138. Lund in , M. ( 1999). Assessment of the Environmental Sustainability of U rban Water Systems. D e p a r tment of Tec h nical Environmental Planning. Gotebo rg, Sweden, Chalmers University of T ech nology: 55. G leick, P. H . (2000). " The changing water paradigm: a look at twenty-first century water resources develo pment." l,f/nter Iutemntio11nl 25( 1): 127-138.

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Conclusions and Recommendations An opera t ional definition of a sustainable water u tility is an important fi rst step in assessing and improving sustainability. M any of the elements of th e definition drawn from multiple disciplines were approved by the water utilities, with

Queensland wh ere growth pressu res are greatest, and the seco nd w ith C itiwater Townsville in regional Q ueensland, where their needs are arguably qu ite di ffe rent. In parallel with the case stud ies, existing approaches to T WCM , both nation ally and intern ation ally, w ill be reviewed to identify options fo r ach ieving m ore effecti ve TWC M in Queensla nd .

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WATER AUGUST 2003

35


II

SUSTAINABILITY

URBAN DOMESTIC WATER TANKS: LIFE CYCLE ASSESSMENT T Grant, M Hallmann Abstract

Sinc e potable s u ppl y wa s not considered, first flush rejection was not necessa ry.

R egion, over 7 years to determine a m edian year. Data were not averaged across years, as the aim of the model was to maintain the sporadic nature of rainfall events, rather than smooth this ou t with yea rly averaging. Ideally a single weather station would have been better, however, un-avernged data was not readily available. Th e savi ngs for each tank were p lotted against the total roof co llection area using rainfall data from 1994 to year 2000. The results from this are shown in Figure I for the 600-litre tank and Figure 2 for the 2,250 L water tank. The graphs show substantial yearly variation in water savings from high in 1995 and very low water savings in 1997. From th ese grap hs, the year of 1998 was selected as a median year in terms of potential savi ngs for a given sec of rainfall data. A nominal roof area of 220m 2 was selected for th e study as no data was ava il abl e o n ave ra ge roof ar eas of M elbourne households. While n o fi rst flush system was assumed 0 .5mm of rai nwater was assu m ed to be lost to roof adsorption and wetting. This was purely an estimate as no data for this was found.

Water Supply

Water Demand

T he rainwater supply m odel looked at daily rain events averaged across fiv e weather stati ons in the Yarra Valley

T he water demand model from the households also aimed to represe nt the typical variation in water use by h o use-

Life cycle assessment and costing of a 600 L and a 2250 L domestic water tank in the M elbourne north-eastern suburbs has shown that sign ificant water savings are possible, that although the energy and materials impact are higher than for reticu lated supp ly they are insign ifica nt compared to other domestic impacts, but with current Melbourne water prices and electricity costs the payback period is longer than the 30 year life assumed. The discounted costs fo r th e 600 L tank are 13% higher and the 2250 L tank some 20% higher than reti culated water costs for garden and toilet usage .

Introduction Yan-a Valley Water, w hich supplies the north - eastern subu rbs of Melbourne, commissioned th e Centre fo r D esign at the Roya l M e lb o urn e Institute of Tech nology to research the fo llowing three questions: • H ow mu ch water is likely to b e saved by usi ng a water tank, given th e seasonality of Melbo urne rainfall and seasonality of water usage patterns? • What are the broader en vironmental implications of the water tank production, installation , use and eventual disposa l? • What are the lon g-term fina ncial implications for residents purchasing water tanks? This paper summarises the results of that study.

600-litre plastic tank used for garden watering only using gravity feed.

Savings for last 7 years with different roof areas (112) 6001 tank supplying garden only

35,c,

-

1994 1995 1996 1997 - 1 998 1999

Methods The two water tank scenarios tested in the study were: • A 600-litre plastic tank used for garden watering only using gravity feed (i.e., no pump installed); and • A 2,250-litre plastic tan k used for garden wa tering and toilet flushin g, with a pump installed with an automatic pressure switch. Mains water (via a backflow preventer) is connected to the tank via a float switch to maintain a minimum level of water in the tank for toilet flushing in times of low rainfall. 36

WATER AUGUST 2003

-

2000

0,C, +-- - - - ~ - - - ~ - - - - ~ -- - - ~ - - -- ~ - - -~ 100

200

300

400

500

600

Rool Sliz•

Figure 1 . Percentage of garden water demand supplied by 600-litre water tank over 7 years weather data showing selected "average" year for use in thi s study.


SUSTAINABILITY

ho lds. Beginning with total water use data from the Melbourne Water Strategy Directions R eport (Sinclair Knight Mertz 2002) of 208.9kl/year, th is total was distributed across the seaso ns (while maintaining the same total annual usage) based on data from the a Melbourne End User and Water Consump tion Influences Study (Institute for Sustainable Futures 2002) . W i nter demand Qune t o September) was assumed to represent the househo lds' usage with no garden wate ring. Garden water demand in each month was calculated by examining the difference between water dem and in each season and the winter water demand. Water use, however, was expected to vary fro m month co month within years so the average water use was then adj usted by climate data fo r each month based on an i n dex developed fro m t he mean max imum temperatures and the n umber of days over 30, 35, and 40 degrees. This was based on assumption that garden watering is frequent in hot weather conditions but is not used on days with above 1111111 of rainfall. T he results of chis process are shown in monthly water usage data in Figure 3 . Garde n water is th e only wa ter considered for the 600-licre tank, while the 2,250-licre tank incl udes water used by toilers. Toilet water usage was assumed to be stable all year rou nd and was estimated to be 19% of the tota l of 208. lkl/year per household (39.69k l per year per ho use ho ld) .

Life Cycle Assessment Life cycle assessment is the process of evaluating the potential effects chat a produ ct, process or service has on the environment over the entire period of its li fe cycle as has been defined by the I nternational Organ i zation for Standa rd ization (ISO, 1997). T h e "functiona l unit" for this assessment was defined as:

2 ,250-litre plastic tank used for garden watering and toilet flushing, with a pump installed with an automatic pressure switch.

with the remainder provided by reticulated water supply for garden demand, and all of the water for the coilec. Scenari o 2B: A 2,250-litre plastic tank, coll ecting water from a 2201112 roof, with all of its ava ilable wa ter being used for garden demand and for toilet fl ushing with the use of a water pump, with the remainder provided by reticulated water supply for garden demand and the toilet. While life cycle assessment atte mpts to look at the entire impacts of production and consumption o f the goods and services used to deliver the func tional unit, in reality this is difficult given the complexity of production systems. A system boundary for the study was established to determine what would be included in the study and what would be omitted. Included in the system bounda1y of the study was the production of the water

S avings for last 7 ye ars with d ifferen t roof a rea s (M2) 22501 ta n k s u pply ing toilet a nd garden

70%

The provision of total water for gardening and toilet ÂŁlushing co an average YVW-region household for a period of 1 year. (Currently equivalent co 113kl based on Melbourne Water average consumption of 208kl per household and with 35% being from garden and 19% being from toilet usage) .

Three scenarios were examined in the study for supplying the functiona l un it: Scenario 1: The total amount of water for garden watering and toilet flushing is provided by reticulated water supply. Scenario 2A: A 600-litre plastic tank, collecting wate r from a 2201112 roof, with all of ics available water being used for garden demand (using gravity feed),

tank and pump (if necessa1y) and all plumbing adjustment required to install the tan k. Data for the tank manufacture was collected from Australian Rotomoulding Industries which produce the tanks sold by Yarra Valley Water. For the materials used in the tank, pump and plumbing adj ustments, material production was traced back as far as the original material extraction processing and manufacture including main transport stages . D ata for th is material production was taken predominantly from Australian life cycle inventory data held by the Centre fo r Design and originally based on Gram er al (1999), however some minor materials suc h as comp lex polymers, copper and brass were taken from European data sources as no reasonable Austra lian data was available. The life cycle inventories for each of the materials consists of arou nd 100 individual items consisting of fossil fuel and mineral resources used, as well as emissions to the environment including greenhouse gases, organic substances, toxic emissions, smog contributors, acid gases, nitrogen and phosphorous nutrients. For reticu lated water supply pumping energy data was taken from Apelbaum Consulting Group (1997) and chemical treatment was included. In addition to this, avoided capital works were credi ted to the water tank scenarios, based on expected savings per household, based on information prepared by Sin clair K night Mertz (2002). For the 2,250-litre tank, 807,350 households were requi red to offset extra supplies w hich could be provided by the Upper Watts River Dive rsio n and the Blue R oc k Lake to Tarago Reservoir. The impactS of these works were estimated and divided by the number of households to determine the credit for each tank installations (Table 1).

-1994 -1995 1996 - 1997 -1998 -1999 -2000

60% 50% 40% 30% 20% 10%

0%

+------~---~----~----~----~---~ 100

200

300

400

500

600

Roof atze

Figure 2 . Percentage of toilet and garden water demand supplied by 2,250-litre water t ank over 7 years weather data showing selected " average " year for use in this study.

WATER AUGUST 2003

37


SUSTAINABILITY

Similarly for the 600-litre tank scenario 1,141,682 households w ere required to offset the Upper Watts R iver D iversion, so appropriate credits were calcu lated for each ho usehold installation (Table l) . W hile it is accepted that this level of tank uptake is unlikely, the infrastructure offset per tank is va.lid as an indicator of potential infrastructure savings, which w ill come about due to a large range of strategies, one of which may be water tank uptake. The material requirements for the avoided infrastructure were estimated from typical pipelin e co nstruction costs. No capital savings were assumed in water distribution infrastructure or storm water infrastructure as the small tanks were considered to have little influence on peak flows, w hi ch define much of the design and sizing of this infrastructure . T he data in T able 2 shows that, on average fo r the 600-litre tank, more than 94% of storm water flow is released by the tank in rain events above 20m m and more than 91 % for rain eve nts above 5mm. These numbers are reduced to an average of7 5%

700

â&#x20AC;˘Garden waler usage estimate 600

500

. ~.. ..

~

400

a.

~

300

200

100

Jan

Feb

Mar

Apr

May

Component

and 60% for the 2,250-litre tank. However fo r the 600 and 2,250-litre tanks there are 15 and 8 days respectively in a year w here no rainfall is diverted. On the w ater supply side, Figure 4 sho ws th e water supply by the tan k over

Scenario 2A 600-lltre tank

Scenario 2B 2,250-lltre tanks

Storage increase. scenario

Upper Watts River Diversion scenario

Upper Watts River Diversion scenario + the Blue Rock Lake to Tarago Reservoi r scenario

increase in water storage (ML)

20,000

50,000

1,141 ,682

Equivalence in households tanks (1 > Pipeline

Lengt h Mass of pi pe work (kg) Welding pipe seam (m)

Pumping Stations

Number copper (kg) roiled stee l (kg) Concrete (kg)

Reservoirs

Number Concrete

807,350

28 22,960,000 28,000 2 5,000 10 ,000 80,000 1 60,000

53 43,460,000 53,000 5 12,500 25,000 200,000 2 120,000

20.11 0.024 4.38 8.76 70.07 52.55

53.83 0.066 15.48 30.97 247 .72 148.63

Material Allocations per household 12> Pipeline

Mass of pipework (kg)

Pipeline

Welding pipe seam (m)

Pumping Stations

Copper (g)

Pumpi ng Stat ions

Rolled steel (g)

Pumping Stations

Concrete (g)

Reservoirs

Concrete (g)

Note: (1) Number of Households In Melbourn e required to adopt the specified water tank (600-lltre in scenario 2A and 2,250-1/tre in scenario 2B) to achieve complete avoidance of the storage increase scenario. (2) The diameters of the pipe for the upper Watts River Diversion and the Blue Rock to Lake Tarago Reservoir were calculated1 to be a diameter of 1 . 7m with a liner mass of 820 kg/ m.

38

WATER AUGU ST 2 003

Jul

Aug

Sep

Oct

No v

Dec

Figure 3. Adjusted seasonal garden water usage data based on daily maximum temperat ures and number of days over 30, 35 and 40 degrees Celsius.

Table 1 . Assumptions on avoided Infrastructure Item

Jun

the year for the 2,250-litre tank, and it can be seen that in high summer, w hen peak demand for domestic water will be experienced , the tank is empty fo r days on end. The data that was included from sto rm water were estimates of reduced emissions of ni trogen ox ides fro m ligh tn in g, transport emissions and industrial processes whi ch chann el into sto rm water and end up in Port Phillip Bay. A major study of NOx emissio n co ntrib uti on to ni trogen load s in wate rways has been unde rtaken at C hesapeake Bay in the United States. NOx emissions were found to be responsible for anyw here from 10 to 40 percent of the Chesapeake Bay's nitrogen buildu p (Editorial 1996). Mi tchell (1997) estimates total nitrogen concentration in rainwater in M elbourn e to be betw een 0.22-7 .1 mg/ L. It could be expected the initial concentration of nitrogen, at the beginning of a rain eve nt, would be highest, with the concentratio n dropping as th e rain cleans th e air. T he rainwater tank is most likely to capture the early part of rain events before it is o verflowing, so it could be expected to captu re much of the nitrogen rich rainwater. In fact, of the 86 days in 1998 with rain above 1m m, the 2 ,250- litre w ater tank coll ected th e first 200 litres of rain o n 60 days. Water collected in tanks is either d ischarged to the garden, where nitrogen may be taken up by the plants and soil, or to the sewer via the to ilet, whereby nutrient loads are managed prior to discharge . Excluded from the study w ere second o rder effects, such as the building of th e factory that produces the tanks, pumps or water supply equipment.


SUSTAINABILITY

Environmental Indicators

to Scenario 1, the mains water only scenario. The 600-llt re 2 ,250-llt re two water tank scenarios The environmental (2A and 2B) have lower Average for events above 20mm 94% 75% indicators were reported on results for water use and Average for events above 10mm 93% 69% individually and not added nutrient emissions Average for events above 5mm 91% 60% into a single environmental (eutrophication) than the indicator, except when Number of days with 1 00% water tank overflow 8.00 15.00 reticulated water supply testing the sensitivity of the scenario. On all oche r results to different variants. Table 3. Capital and maintenance cost of tank over 30 years. indicators the water tank The individual indicators sc enar ios hav e higher Tank Capital 600-lltre Tank Capital 2 ,250-lltre were normal ised aga inst a impacts due co increased national per capita reference $370 +38.50 delivery $510 +38 .50 delivery Tan k energy and material use. (that is divided by the total $35 $70 Plumbing The net value for nu trient average impact in eac h Plumber $150 $200 emissions for the 2,250-litre category for each Australian). Pump $350 tank (scen ario 2B) are Life Cycle Costing $100 Electrician nega tive because the water $1,268.50 Total $593.50 tank is diverting more T o determine the n it rat e from rainwater $529 Pump Replacement economic benefits and costs emissions that is being of the water tank from the Note pump replacement is assumed after 1 5 years and price is released across all life cycle consu mers' perspective, a assumed to increase by 3% per year in line with CPI. stages of water tank life cycle costing was underproductio n and use. taken. T he costing was done Results Figure 6 shows the same data as in over an assumed 30-year life of the water Table 4 shows the resulting water Table 5 but d ivided by th e national per tank. A discount rate of 4% per annum savings achieved by the 600-litre and was used to adjust the value of future capita impact fo r each ca tegory. This 2,250-litre water tanks. The 600-litre tank results in norma lised data w hich give an expenditure and an annual inflation rate is used for 104 days and supplied 17 .Ski of 3% was assumed. indicati on of how significant the water of water. On the other days of the year supply via the three sce narios, is in Costs included in the assessment were it is either empty or not needed (assuming relatio n to overa ll impac ts in each the purchase of the water tank and pump no garden watering is needed in winter, environmental category. It shows clearly and installation costs. Water and electticiry or on days of significant rain events in that the costs over the life of the tanks was also water use indicator is by fa r the other seasons). The total saving for the included, however, additional capital m ost significant resu lt of all the indicators household water bill is around 8.4%. T he works were assumed to be built into th is examined. Solid waste from disposal of 2,250-litre tank saves around 62k1 of water water price and were not itemised the tan k at end o f life is the next most as it has greater holding capacity and is sepa rately. therefore empty less often, but also is used significant indicacor. fo r the toilet as well as garden applications, T he results for the life cycle costing Economic Aspects and can therefore be used to some extent w ere calculated as net present values for all year. water supply for the toilet and garden Table 6 shows the resul ts of the life cycle costing in net present va lues with water demand. Table 3 shows the main Environmental Impacts scenario 1 being the cheapest option, and cost data used in the tank purchase and scena rio 2B (the large tank installed with Table 5 shows the absolute results for installation while electricity and water a p ump) bei n g about 20% more the three models of the scenarios wh ile supply were costed at S0.1368/kwh and expensive. All options have net costs Figure 5 shows the same results relative S0.7523/kL respectively. Table 2. Percentage rai nfall overflow from rain events.

Table 4 . Mains Water Savings during t he 1-year use of t he tank. Scenario

Mains water saved Litres per year

Reticulated water required to top up garden and toilet total usage (Litres)

Mains water saving for garden/ toilet use

Proportion of total household water from tank

Number of days that tank supplies water

Comments

Scenario 2A

17518 L

95288

15.5%

8 .4%

104

600-litre tank for garden use only, no pump

Scenario 2B

Garden 32900 Toilet 29031 Total 61931

50875

54.9%

29.6%

272

2, 250-litre tank for garden use and toilet, with pump

Assumptions

Rainfall data from 1998 for Yarra Valley Water region. Available roof area: 220 m 2 â&#x20AC;˘ Rainwater lost to roof adsorption and wetting: 0.5 mm. No first flush system used. Tank overflow directed to the stormwater. Garden not watered in winter months, nor on days with rainfall above 1 mm.

WATER AUGUST 2003

39


SUSTAINABILITY

800

,,..."

700

J!::,

600

Q. Q.

...

:, ~

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. - ... · · usage

500

- - supply by tanks 400

0

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C

..

300 200 100

!

~

(100) C

,"

. ,. C

C

.,,

a,

,

N

,,

" ,;, u..

.,,

;"

. .

!

~

Q.

'!' a,

Q.

! N

..... ....

"',.:.

~

;;:;

.. .., C

,:,

C

:,

~

>

u

z

~

0

'"

"

Figure 4. Tot al water demand by garden and toilet and supply of water by tank for 2,250-litre tank being used for garden and t oilet applications.

associated with their implementation. The additional coses of the pump make the larger water tank less favourab le even though more water is saved .

Avoided water storage infrastructure is not insignificant in the context of water tank use, however it is not large enough to offset the impacts of the water tanks

conscrnccion and o peration (except potential ly in environm e ntal flow-related impacts which have not been included in chis study).

Discussion and Conclusions Water Savings

T he two water tan ks investigated in this study lead to significant reductions in water use from reticulated supply. This is in the order of 8% of total household dem and for the 600-licre water tank and 30% fo r the 2,250-litre water tank. For toilet and garden water demand, the areas where the tank is targeted for use, the sav ings are 15% for the 600-licre water tank and 59% for the 2,250-litre water tank.

Table 5. Characterisation of impact s from each scenario.

Environmental implications

Water Use

Using data supplied by M itchell (1997) ni trogen capture by the rain, which is diverted from sto rm water through water tank collection and use, leads co reductio ns in nutrient loads to local rivers and screams and Pore Phill ip Bay. The energy and material impacts of water tank manu facture and operation are substantially higher, in percentage terms, than the energy in equ iva lent reticulated water supply, especially w hen a pump is used with the water tank. T he scale ofche impacts needs co be kept in perspective. The overall additional annual impacts of having a water tank installed (for greenhouse impacts), are roughly equivalent to 20km and 60km per year o f car travel for the 600-litre and 2,250-licre tanks respectively. This suggests that the absolute impacts of the water tank are not large in proportion co ocher impacts. T his is reinforced by th e normalised resu lts for the three options, w hi ch show water use to be the most signifi cant envi ro nm ental indi cator in the study.

Solid Waste

40

WATER AUGUST 2003

Impact category

Unit equivalent

Scenario 1

Scenario 2A Ave waste

Scenario 28 Ave waste

Global Warming

kg CO2

g S04 g P0 4

11.9 56.2

14.2 66.1 3.25

33.6

Acid ification Eutrophication Heavy metals

mg Pb mg B(a)P

Carcinogens Photo Oxidant. Formation

g C2H4

Cumulative Energy Demand

MJ kl H20 kg

10.9 21.0 0.482 0.378 132 113 1.29

27.9 0.530 11.5 200 95.3 2.20

152 -13.1 45.5 1.08 22.1 435 51 4.64

8222% 4133%

332%

Cl S cenar io 2a 188%

208

264%

% • Scenario 2b

137%

155%

-214%

-~

-~

! Figure 5: Comparison of wat er tank scenarios with the baseline (reticul ated water supply) for each environmental indicator. Note: Scenario 2A 600-litre tank for garden, Scenario 2B 2,250-litre tank with pump for garden and toilet usage.


SUSTAINABILITY

Financial implications

Nei ther the 600-litre nor the 2,250litre tank pay back within the 30 years unde r current water prices and the assurn.ed 30 year life of the tanks and their components. If water p1ices were approximately 25% higher, th e 2,250-litre tank would pay back in 30 years. The discounted costs for the 600-litre tank are approximately 13% high er than reticulated water costs for garden and toilet usage . The discounted costs for the 2,250-litre tank are 20% higher than reticulated water costs for garden and toilet usage. Other issues

Table 6. Results of the life cycle costing in net present val ue with discount rate of 4%.

Scenario 1

Scenario 2A - 600-litre tank $2 135

$2 412

$2 568 PJn"p(r,t.aland repllcen-ent) , $74',29%

Tani< (capital), $609. 2S%

Water. $963, 38"

W ate r

,..,.

$2,135,

Tarik(c&l)Q~. $799,31%

The Authors

The smallest commercial water pumps currently being used for water tank applications can deliver around 50 litres per nunute. While fo r garden usage this may be needed, for toilet water a much slower rate of 5 litres per min ute could be tolerated , This suggests that currently used pumps may be o versized and inefficient given th e relatively small task requ ired and alternative solutions to supplying water into the toilet wo uld improve its impact substantially. There is a range of improvements and optimisations w hich ca n reduce th e overall impacts of the water tank and bring it closer in energy and green house terms, to the impacts of reticulated water supply. Further work compari ng the e n ergy efficiency of water tanks, as a water co nservatio n measure, comp ared with other strategies, would be of valu e.

Scenario 2B 2,250-litre tank

Dr Tim Grant is Assistant Director Manager of th e Centre for Design at RMIT Unjversity, Melbourne, email: tim.grant@rmit. edu.au. Mark Hallmann is cu rrently a Master candidate at University ofTwente , The N etherlands.

References Apelbaum C onsulting Group (1997). T he Australian transport task, energy consumed and green house gas emissions Volume 2. Barton , ACT, Dept. of Primary Industries and Energy. Edito,ial (1996) . "Cross-Media PoUution and the C hesapeake Bay." Reso11rces Fo r the F11t11re, Summer 1996, (124). Goedkoop M J (1995) . Eco-i11dicntor 95 - Fi11al report. Amersfoort (N L), NOH report 9523 and PRe Consultants. Grant T (I 999) . Life Cycle Assessmenc- Australian Data Inventory Project - Summary R eport. Melbo urne, Centre fo r Design at

RMIT and C R C for Waste Management and Pollution Control. In stitute for Susta in abl e Futures (200 2). M e l bourne E n d User and Water Consumption Influences Study. R edfern, Institute for Sustainable Fumres: Page 18. International O rganization for Standardization ( 1997) . !SO 14 0 40 Environme n ta l M a n age m ent Standa rd- Li fe Cyc le Assessment, Principles and Framework. Sydney., Australian Standards - Published as AS 14040: 1998. M itchell V G,. M cM ahon TA et al. (1997). Modelli11g the possible 11tilisatio11 efston11111ater a11d 111aste111a1er within a,1 11rba11 catcl1111e111. AWW A 17th Federal Conventi on, M elbourne, Clayton, Vic., C R C for Catchm ent H ydrology. Sinclair Knight Mertz (2002) Issues associated with accessing new water resources for greater M elbo urne. M elbou rne Water Strategy Directions R.eport.

Fraction of Australian, annual per capita impacts

Global Warming

.

No tank

Acidification

.

Heavy metals

Eutrophication

600litre tank

.

Carcinog ens

2250 litre tank

Photo Oxidant Pesticides Formation

Cumulative Energy Demand

Water Use

Solid waste

Figure 6. Comparison of water tank scenarios wit h against national per ca pita impacts for each indicator category (normalisation).

WATER AUGUST 2003

41


~

WATER

REUSE

THE HAWKESBURY WATER REUSE SCHEME CA Booth, R Attwater, C Derry, B Simmons Abstract Reuse of treated effluent and harvesting of stormwater are gaining broader recognitio n as m eans of conserving a valuable resource, while reducing impacts from poll utants and nutrient loads on our river systems. Th e Hawkesbmy Water R euse Scheme seeks to showcase an integrated approach to eilluent and stonnwater reuse and constructed wetland technologies, and provide a focus for community awareness of the potential benefits of water reuse.

Introduction The Hawk esbury Water Reu se Schem e (H WRS) is centred within the HawkesbL11y Campus of the University of W es tern Sydney (UWS) in Riclm1ond NSW, approximately 80 km northwest of Sydney. T he campus has a histo ry of agricultural and horticultural studies, and is developing a long-term focus on issues of sustainability, particularly as they relate to urban and rural landscap es . The Hawkesbury Water Reu se Scheme has been built upon partnerships between the University and Sydney Water Corporation (SWC), Richmond TAFE, H awkesbL11y City Council , and Clean Up Australia. T hrough these partnerships, and w ith its focus on issues of sustainabili ty, the Scheme is an important element of the developing UWS Water R esea rch Program. Experiences derived from t h e manageme nt, research, and outreach activities associated with the Scheme will be relevant to water reuse initiatives developing around the urban- rural peripheries of coastal cities and inland regional townships (Simmons et al. 2000). T he Scheme provides an opportunity for the partners to pursue the social and environmental benefits of water reuse, including: • Nutrient recycling, harvesti ng and beneficial use for agricul tural production; • Minimising the impacts of effiuen t discharges into the H awkesb my-Nepean River System; • Influencing reductions in Sydney's potable water demand; • Promoting practical, acceptable and safe management strategies and practices . UWS outreach programs associated with the Sc heme seek to promote

42

WATER AUGUST 2003

Figure 1 . The Hawkesbury Water Reuse Scheme and Richmond township.

awareness, education and changes in behaviou r towards greater community accep tance of water reuse. In doing so, challenges in monitoring behavioural changes will be researched and an integrated total water cycle management advocated and advanced. An Environmental Management Plan (EMP) has been prepared for the HWRS as the technical refe rence for the Agreement between UWS and SWC concerning the supply and use of treated effiuenc from the Richmond Sewage Treatment Plant (STP). In its preparation, consideration has also been given to the possibility for the EMP to be upgraded to an Environm ental Management System (EMS). T he structure of the EMP builds on the AS/NZS ISO 14000 series guidelines on p rinciples, systems and supporting techniques (Standards Australia 1996).

A general description of the Hawkesbury Water Reuse Scheme Wet wea t her flows from the Richmond STP, and urban and rural stormwater from Richmond township flo w through the HWRS area, into Rickabys Creek and then enter the H awkesbury River, just upstream of Windsor. An important element within the HWRS is the Ri chmond Water Reuse Project, a Clean Up Australia " Fix U p" project. Through a UWS partnership with Clean Up Australia and the UWSH

Founda ti o n , treated effl uent a n d stormwater harvesting infrastru cture has been built incorporating separate wetland systems for treated effluent and stormwater polishing. An aerial photo of the location is shown in Figure 1, and a general sc hematic in Figure 2. Effluent treatment and use

The Richmond STP currently uses trickling fil ter technology to ach ieve secondary level treatment of the effl uent, fo llowed by disinfection. An upgrade of the Richmond STP to an IDAL (interm ittent decanted aerobic lagoon) plant wh ich supports biol ogical ni trogen removal is planned fo r completion in lace 2004. The Richmond STP currently has a capacity of 14,000 EP (equ ivalen t persons) and an average daily flow of 2.SML, or average annu al production of 927ML (H ird 1998). It is feasible that in approximately 5 years, effluent from North R ichmond may be piped to the R ichmond STP, increasing average daily flows to 4 M L/day. Trea ted effiuent from Richmond STP is collected in a Receiving Pond, and then pumped up into the first University storage, the Effiuent Turkey Nest Dam (capacity 93 ML). Prior co the construction of the in-line Stormwater Detention Basin (capacity 60ML), wet weathe r di scharges fr o m the STP overflowed from the Receiving Pond down the stonnwater channel to Rickabys Creek.


WATER

Treated efflu ent is piped from the T urkey N est to the H o rticultu re D am (capacity 84 ML), Hillside D am (capacity 76 ML) and directly to the cropping area n orth of B lacktow n Rd. B etw een the Turkey N est and the Horticulture Dam, supply lines lin k the D eer Farm and Grazing U nit to the Schem e. Supply lines from t he H orticulture Dam include one line to the playing fields, and a pressurized lin e t o th e H o rse Un i t and th e Horticulture areas. Storages for th e H o rt i c u l tur al a r eas in c lu d e t h e H orticulture T ank (capacity 0.1 ML) and the Yarramundi D am (capacity 6.5 ML) . T h is system of infrastru ctu re supplies a n umber of water users, including th e irriga tion o f • Pasture for the UWS Daiiy, H orse Unit, and Grazing Unit; • A range o f ho rticultural crops and orcha rds; and • Un iversity p laying fi elds. T h e EMP recogn ises a pri n cipal challen ge o f water reuse schemes, w hich is optimising storage manage me nt, and endeavours to strategically address this key issue . T argets ha ve been identified o n the basis o f m odelli ng ava ilabl e storages and minimisin g risk o f dry weather discharges o f treated eillu ent to Ri ckabys C reek Uames 2000) . As sto rm wa cer supplies co me o n- line to supplem ent current treated eilluent supplies in Hillside Dam and H o rticulture Dam , and additional storages are incorpo rated in the Schem e, th ese targets w ill b e rec onsid ered . H o w ever, they do provid e relevant managem en t targets given the storage limitation fo r treated efflu ent and the need to have substantive storage capacity prior to the win ter pe riod o f lo w irriga ti o n dema nd. Foll owing the deve lop ment of the EM P, an initial risk assessm ent was undertaken . T he assessment identified the prelim.inaty risk manage ment needs of the broad ran ge of staff, contracto rs, students and general public who util.ise the campus facilities. Fu rth er strategies for risk co m munication and m anagement will be developed (D erry, B ooth and Attwa ter 2003) . C omplementary research regarding efflu en t treatment and use includes q ues tions o f soil sustain ability an d m o nitorin g (A iken 2003), ground water impacts, and th e es tablish m e n t of co nstructed wetlands.

REUSE

Richmond STP

....: ......... ··,!""' ""~i ::

,:.:::--

University of Western Sydney Hawkes bury Campus

Environmental Flows

UWS Dairy

Yarramundi Horticulture Area

c::::::::::> c::::::::::>

Treated Effluent Stormwater

Figure 2. A genera l schematic of effluent and sto rmwater infrastruct ure.

P ty Ltd. T hese wetlands, built as part o f the R ichm ond W ater R euse P roj ect, are capable of capturin g and storin g wet weather £lows from th e ST P for periods o f up to 5 days . A maximu m of 24 ML o f ST P we t weather £lows will be sco red in th ese wetla nds. These £lows will be stored fo r periods of at least 10 days and then progressively pump ed back to the Effluent T u rkey Nest Dam. O pportunities to link these captured wet-weather £lows back to th e !D AL plant for further treatment if required are under consideration by UWS and SWC. Op e ra t io n al proto co ls fo r th e management of treated effluent within the we tlands w ill b e developed with in th e EMP. T hese proto cols will assist in mi n imising th e n eed to discharge disinfected and treated efflu en t to R ickabys C reek and will optimise the integrated wa ter harvesting and sto rage capabili ties of the overall Scheme .

Effluent Wetlands

Stormwater treatment and use

An innovative, low cost system of Effluent W etlands has been designed, based on concepts collaboratively developed with the UWS School of Engineeri ng and Industrial D esign and Australian W etlands

T he H WRS uses a total wa ter cycle management approach to integrate the above use o f treated eilluent with treated storm wacer. As ou tlined previo usly, the R ichmond Water R euse Projec t has

provided key infrastructure for stormwater harvesting, p olishi ng and reuse. A 60ML Stormwa ter D etentio n Basin has been constructed at the junctio n of th e two mai n sto rm wa ter chan nels draining the upper catchment o f Rickabys C reek. A 90ML Storm water Turkey Nest D am has also been constru cted to store treated storm w ater. On co mp letion o f th e proj ect, captu red stormwater w ill pass through a series of constructed wetlands and be stored in a 25M L H old ing Pond fo r either p umping fo r storage in the Storm water Tu rkey Nest D am o r fo r release co R ickabys C ree k as environn1enta l £lows of improved wa ter quality . C u rrent stormwater m odelling by Stewart (2003) w ill suppo rt the integrated and equitabl e allo catio n of this val uabl e resource fo r both water users and environmental £lows. As part o f the Richmo nd W ater R euse P roj ect, considerable additional infrastru cture in the form of pipes and pu m ps h ave been provid ed as in-ki nd contributions by a range of industty and business partners. This additional infrastructure has been installed to link th e captu re, treatment and storage elemen ts w ith th e H illside D am and upgraded WATER AUGUST 2003

43


WATER

infrastructure at Richmond T AFE. A proposal w ithin the EMP stro ngly recommends linkage of the treated stormwater supply with Horticulture Dam. This would enable maximum flexibility of use of the two recycled water supplies. Stormwater Wetlands

Similar to the Efiluent W etlands, c ollaborative conc ept d ev elopme n t resulted in a se ri es of Stormwater Wetlands being designed to polish harvested stormwater. The four onehectare w etlands will deliver water to the 25 ML H olding Pond mentioned above. D etention times will be sufficient to produce a quality of storm water suitable for uses including the provision of supplies to Richmond T AFE and as a back- up supply for the treated effluent, particularly in summer periods of high irrigation demand and during drought. T he wetland design allows a multitude of wetland filling and holding (treatment) scenarios which are important for research and demonstration purposes. A developing research program, in partnership with Australian Wetlands Pty Ltd, w ill investigate the role of 'self-design' in the

REUSE

establishment of ecosystem function of stormwater treatment wetlands. The protocols fo r capturing and treating stormwater will be identified in the EMP for the Scheme. Also, the environmental flows will be released from the Settling Pond in accordance with protocols to be developed with the NSW Department of Infrastructure, Planning and Natural Resources and operationally enabled though their inclusion within the UWS Environmental Management Plan.

The role of the Hawkesbury Water Reuse Scheme in water research for Western Sydney The HWRS described above is an important element within an integrated suite of applied research and demonstration fucilities being developed by the UWS. Complementa1y initiatives are also being pu rsued and in clude an Onsite/Decentralised Wastewater R esearch and Training Centre. These, and other initiatives, fo rm part of the UWS "Water Futures R esearch Initiative" wh ich is a 'whole-of-univ ersity' transdisciplinary research program (Davey 2002) . This initiative seeks to utilise and build upon th e broad environmental, so cial and

economic research base of UWS to help address k ey water management issues of significance to Sydney and its water supply catchments. The "Water Futures R esearch Initiative" recognises the unprecedented challenges faced in managing the urban water cycle on a more sustainable basis.

The Authors All are members of the University of W estern Sydney, Hawkesbrny Campus. Adjunct Associate Professor Sandy Booth is the leader of the Integrated Ca t c hm e nt a nd En v i ro nm enta l Management (ICEM) R esearch Group, with over 25 years of experience in natural resou rce management issues in Australia and the Asia Pacific R egion. Email: s.booth @ u ws.e du .a u. Dr Roger Attwater has also worked on a range of catchment management issues and projects in NSW, WA, ACT, Thailand and now in China. Email: r.attwater@uws.edu.au. Chris Derry is an epidemiologist/risk analyst w ho has worked on a number of water consultancies locally and internationally. En1ail: c .derry@uw s.edu.au. Bruce Simmons is Senior Lecturer, En vironmental Management, currently su pervising four research programs in stormwater and wastewater harvesting and reuse. Emai l: b.si111n1ons@uws.edu .au.

References

Westwater Enterprises specialise in the design su pply and application of Disinfection Equipment for Water & WastewaterTreatment, including:-

Gas Chlorinators Liquid Chlorine Evaporators Sodium Hypochlorite Dosing Ultra Violet On Site Generation Total Integrated Packages

WestWater Enterprises are th e sole principal agents and distributors for the Portacel range of Chlorination and Ammoniation equipm ent throughout Australia, providing complete spares, service and mainte nan ce back-up. Equipment can be supplied as individual items, or as packaged systems custom designed to meet your specifications and application. Westwater Enterprises also supply a range of process monitoring and control instrumentation, including:Cylinder & Drum Weighing Systems Automatic Gas Shutdown Systems Chl01ine Residual Analysers Gas Leak Detection pH, c;onductivity, DO and other Momtors. Unit I I 36 Hillrose Drive, Malaga. WA. 6090 Tel: (08) 91481411 Fax: (08) 91481511

Note: No association with FluidquipAustralia Pty Ltd exists

44

WATER AUGUST 2003

Davey P (2002) f,Jlater ji1t11res research initiati11e, U11iversity of Westem Sydney, summary paper prepared fo r UWS Office of Research Services. Derry CW, Booth S, Attwater R (2003) "A risk management approach to sustainable water reuse ." E1111iro11111mtal Heal//, 3: 34-43. Hird C (1998) Audit of efflue11t re-use actillities Rid,mond Sel/lage Treatm e11t Pla11t, AGSOL Pcy Ltd. University ofWestem Sydney (2002) Ha111kesb11ry f-Varer Reuse Scheme: ÂŁ1111/romueutal i'vfmiagemwt Plan. Simmons B, Attwater R, Booth S (2000). "Water harvesting and reuse: a regio nal township model", in: Dillon, PJ (ed.) A11Stmlia11 Water Associatio11 vVater R ecycli11,~ Forum, Proceedi11,~s of tlie First Symposium, Water R ecycli11g Australia 2000, Adelaide 19-20 October 2000. Aiken J (2003) DNA based bacterial co111111u11ity analysis and ,vastewater soil rnstai11ability, Student presentation to AW A Waterscape Conference, 22-23rd May 2003, Sydney. James E (2000) Modelli11g Irrigatio11 Use ef FJJ111e11t ji-0111 R ic/1111011d STP (Seivage Treatmem Plmu). Technical report prepared for UWS, Sydney Water Corporation. Standards Australia/ Standards New Zealand (1996) AS/ NZS ISO 14004: E111,iro11111e11tal 11ia11age111e11t systems - gweml guideli11es 011 pri11ciples, systems and supporti11g tecf111iq11es, Standards Australia, Sydney. Stewart J (2003) Modelli11g ,if cliemical, a11d biological respo11ses i11 waters collected as n111<!f]'fro111 a r~~i,mal 1011111ship, PhD progress report, ARC Australian Postgraduate Award.


D

WATER

REUSE

ATTITUDES TO RECLAIMED WATER FOR DOMESTIC USE: PART 1. AGE J McKay, A Hurlimann Abstract This is th e first o f three articles explorin g responses of a section o f the Australian com_munity to having reclaimed wastewater and storm water plumbed into their house. The co mmu nity is loca ted in Ma wson Lakes, South Australia, in an innovative greenfields development which is a pub lic-p rivate partn e rship. Th e reclaimed water w ill be used insid e th e ho use fo r toilet flushing and also for outside use, for example for irrigation. Th e delivery of the reclaimed water is du e to commen ce at the end of 2003 . O ne predictabl e result was that the support fo r the use of reclaimed water decreased as the use became more personal, but this was slightly less evident for yo unger perso ns than for those over 50 years o ld. Key Words: Water recycling, reuse, urban, storm water, wastewater.

Introduction Th e acceptance o f water recycling proj ects depends largely upon the attitudes o f the communities involved . Without public acceptance, water recycling projects struggle to be success fully impl em.ented. In C ali fo rnia, ob taining finan ce and gaining public acce ptance were the tw o main obstacles id entified to overcom e when implementing reclaimed water use (Young 1989) . A number of reuse schem es in Am eri ca have been abando n ed after community acceptance was lacking (Okun 2002). Globally there has been limited res ear ch c ondu c ted on co mmunity attiwd es to the u se of re claim ed wastewater. Research in this field is notably lacking in Australia. Dillon (2001), identified the highest research priority for water research in Australia is to address publi c acceptance of reuse . This article presents aspects of the results of a survey w hich gauged a parti cular Austra lian community's attitudes to the proposed use o f reclaimed water for non p o t a bl e r es id e nti al purpo ses. Th e community is the gree nfi elds development at M awson Lakes, near Adelaide.

The results o f this survey can, however, be generali sed to the general Australian population.

Dual Water Supplies and the Importance of Wastewater Reuse W astewater reclamation and reuse is becoming increasingly required as an alternative supply o f water and in vestment in drought- proofing an area (Okun 2002). Presently, wastewa ter reuse applica tions through out the world are limited in applicati on to predominantly irri ga tion and industrial purp oses. The b enefits of wastewater reclamation are far reaching and include add itio nal wa ter supply, avoidance of tec hnology expansio n , reduced disposal of wastew ater to sensitive environments, reduced energy use and econo mi c savings (W olff and Gl eick 2002). Wastewater reclamatio n in United States o f Am erica has been led predominantly by the State of C alifornia, a water-scarce regio n. ln the C ity of Irvine, C alifornia, new develo pments must be built with dual water supply systems for land sca p e irrigati o n . Despi t e ini ti al investment in infrastructure for th e system, the dual reticulation has been economically beneficial for use rs. Sewer charges have been lowered by 36.5% o ver several yea rs and reclaimed water is sold at 90% of the price of do mestic potable water (Irvin e R anch W ater District 1994). A tiered water pricing system is predominantly used in California, imposing high er tari ffs for higher consumption. The price o f reclaimed wa ter is highly variable throu ghout California, ranging fro m 75% to 100% of the potable water price . R eclaimed wa ter infrastru cture costs are o ften met through government bonds and grants, lo w interest loans, tariffs, and property taxes (Byrnes 2000). Irvin e and oth er American examples are relevant to the development of Australian dual water supply systems, o f whi ch there are few examples. Globally there has been limited research conducted on conununity attitudes to the use of reclaimed wastewater. Of the studies

do ne, fruitful results have been obtain ed. An assessm ent of commun ity attitudes to the use o f reclaimed water condu cted in C alifornia found that th e m ore personal the proposed use of recycled water is, the less fa voured it becom es - eg. there is a grea ter acceptance fo r the use o f recycled water for irrigation o f golf courses then for potable use (Bruvold 1979). This study assessed peopl e's attitudes to a ra nge o f reclaim ed water uses including; drinki ng, bath ing, boa ting, irrigation of vegetable crops, and road construction. In England , research found there was broad conditional support for water recycling 0effrey and J efferso n 2001) . 86% of resp ondents agreed with the statem ent ' I have no objection to water recycling as lo ng as safety is guaranteed. ' This study also found that using recycled water from second party o r public sources was less acceptable. Th ese above-mentioned studies w ere h ypoth e ti cal situ atio n s, the p eo ple surveyed did not use reclaimed wastewater nor were there plans fo r this in the near future . Dual water supply systems making use of stom1 water and wastewater for internal household reuse are rare in the world, even current gree nfields developme nts in Australia rarely incorporate dual water su pply. Th ere are two w ell-kno wn Australian examples of reuse, Rouse H ill and N ewington , both suburbs o f Sydney, and a third being developed at Mawson Lakes n ear Adelaide . Rouse Hill is a new residential subdivision in northwest Sydney with a dual supply. Unlike Mawson Lakes, stonn water is not reused within this dual supply system. The first stage of this development incorporating 12,000 d we llings ha s recently been completed. Th e dual reti culation sys tem di stributes reclaim ed wastewater fo r non-potable uses including toilet flu shing, car washing, garden watering, fire fighting and park and open space irri ga tion. The system was installed to redu ce potable water consumption and reduce th e environmental impact o f the population on the major river system n earby which is used for recreational and WATER AUG UST 2003

45


WATER

REUSE

this, the MFP concept proved to industrial purposes (Law 1996). Rouse Hill's dual reticulation be a catalyst for a series of environmental projects in South system has gained international Australia, including the Barker recognition for the larger size of Inlet wetlands, and the Virginia the reclaimed water lines which Pipeline Scheme. enables them to cope w ith fire fighting, permitting potable water Mawson Lakes is located 12km 10 pipes to be reduced in size to aid from the Adelaide central business the maintenance of drinking water district and in March 2003 there quality (Okun 2002). were 570 occupied dwellings with a population of approximately The 2000 O lympic Village in 1,500 residents. In 20 10, the Newington Sydney has a dual Mawson Lakes population is water supply. Wastewater and expected to total 10,000 residents, storm water from the suburb is 10,000 workers and 5 ,000 tertiary- treated prior to distristudents. The Mawson Lakes bution to residential allotments, development has a mandate to commercial buildings and develop and incorporate a number parklands through the lilac dual Figure 1. Factors contributing to t he respondent's choice of ben chma rking innovati ons reticulation system (Taylor 2003). including water cyc l e This recycled water is used for to live at Mawson Lakes. management and an ene rgy toilet flus hing, garden watering, • The nature and degree of education conservation system. An encumbrance on and washing cars. At Newington the provided title requires the population at Mawson recycled water currently costs 77 .5 cents Lakes to install a dual water supply system • T hreat of dams, river disposal or ocean per 1000 litres, this is 15 cents cheaper than in their house at the time of construction. the potable water supply (New South outfall The installation of this dual water supply Wales Government 2003). • The 'Not in My Back Yard' Syndrome system must conform to South Australia's • Credibility and degree of cohesion of the Economics and Education R eclaimed W ater Guidelines. Authorities on recycling, and Dual water supply systems have the The dual water supply encumbrance • Demographics (Nexus Australia 1999) potential to reduce potable water demand requires homes at Mawson Lakes to be by 50% (Anderson 1996; Marks 2000). Mawson Lakes connected to a non-potable reclairned However, dual water systems require high water system with lilac pipes and taps in Mawson Lakes is a greenfields develup-front capital to establish the second addition to the normal potable mains. opment in South Australia, a joint venture reticulation system and second household Reclaimed water will be sourced from between the South Australian government plumbing system. At current Australian storm water and wastewater generated by and private industry (Delfin Lend Lease prices this averages an extra $1400-$17 50 the Mawson Lakes development . Consortium) . It derived from a more per allotment at Mawson Lakes. Currently, extensive Commonwealth Government Wastewater from the development will be a 600sqm block at Mawson Lakes costs on transported to Bolivar (8km away) and project called the Multi Function Polis, a average $100,000 with a conventional treated in a wastewater reclamation plant concept originating in the 1970's initiated home costing an average of between to Class A standard. The reclaimed water by the Japanese Governm ent. MFP $170,000 and $200,000 to construct. will then be transported back to the develAdelaide was seen as opportunity to T hus the extra is a small addition for the opment for reuse on the residential demonstrate environmental challenges at individual, but the community saves allotments and for the irrigation of p ublic this site and others could be overcome with much more in the avoidance of capital open spaces. Storm water will be harvested new environmen t al management costs, community opposition to dam from the development and following techniques (H amnet 1998). building, and costs to the environment. primary screening will be renovated The N ational Capital Plann ing The high up-front cost of dual water through a series of engineered wetlands, Authority was commissioned to develop supplies can thus be off-set by long term this renovated storm water will be mixed urban design principles for the MFP; their savings, which include avoidance of work triggered debate about the future of with the reclaimed wastewater prior to technology expansion, reduction in waste being distributed through the dual water Australian cities and urban consolidation. disposal treatment costs and benefits to the supply syste m. Aquifer Storage and The Authority suggested a linear plan, with environment. Public knowledge and Recovery (ASR) will be used to balance high density, the promotion of walking, acceptance of these benefits w ill ease the supply and demand. Reclaimed water will cycling and public transport use, and the path of future development to install dual be used for toilet flushing, garden watering, development of water features and an systems to reuse water . and car washing. The Mawson Lakes Joint urban forest. The MFP unfortunately failed A background report on education venture is currently reviewing options for to gain public acceptance in South needs prepared for the Queensland Water storm water renovation. At present mains Australia because of weakening federal and Recycling Strategy identified that there are water is being delivered through the international support and fears by the local a number of determinants of public recycled water taps until construction of community relating to the creation of a acceptance and support of water recycling. the reclaimed water system is complete. Japanese enclave (Parker 1998). The These include; The reclaimed water is proposed to be purpose of the MFP was never well • The history of the area cheaper th an the potable supp ly. defined. Its failing damaged Australia's • Terminology used Information has been provided by the reputation internationally as not being able developer to potential buyers, which to deal with major projects - except for • Degree of public involvement m the informed them that the dual water supply development of options sporting ones (Hamnet 1998). H aving said

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WATER will have a cost benefit for chem. The developer published information seating chat while there will be additional building costs associated with the system installation, but they anticipate the residents will benefit from on-going cost savings through the availability of recycled water at a lower cost. The actual cost of the reclaimed water has not yet been fi nalised or disclosed. It is expected the potable supply will attract the supply charge, but in order to keep the total bill lower the reclaimed supply w ill not have a supply surcharge. T he bill for water from this meter will then actually reflect water use in the toilets and external use very clearly. However, this assumes that people wilJ use the sam e volu me of water. T he cheaper price and assured availability of the reclaimed water may indeed encourage wasteful water use on lawns etc. It may also encourage some people to use the reclaimed water for clothes washing or other applications. The rest of the study will address these issues and the characteristics of the people who adopt these differing behaviours.

Methods A benchmark survey o f the Mawson Lakes popu lation was conducted in September 2002, prior to the commencem ent of reclaimed water use. Ac chat stage there were 347 occupied households at Mawson Lakes. Members from 136 of th ese households were surveyed. Surveys were in a telephone interview by a professional research company. The survey included openended questions regarding proposed use of recla imed water and a series of 21 attitude and perception statements as well as broader questions abou t their reasons for moving co Mawson Lakes, their attitude co environmental protection, and communi ty issues of most concern co chem.

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live at Mawson Lakes. This indicates the dual water supply system was a very low priority in the residents' decision. Figure 1 displays the percentage of respondents who raced each of the 12 factors as their number one choice to live at Mawson Lakes. General attitudes

It was interesting to note the high level of support for water recycling in general. When asked "What are your feelings about water recycling in general," many respondents expressed belief in the importance of water recycling w ith co mments including: • ' it is a necessity' • ' important in futu re years to save water' • 'excellent idea, we need to do more of it,' and • 've1y important, I am looking forward co the water recycling getting up and running' However, the support for reclaimed water use decreased as the proposed use became increasingly personal. Participants were asked what th ey th ought about the use of recycled water in general, for use on the lawn, fo r clothes washing and

drinking. A significant decrease in support for water recycling was found as the hypothetical use for water recycling became increasingly personal eg from the irrigation of lawns to drinking. These results are shown in Figure 2. Additionally, as the proposed use for recycled water became increasingly personal, respondents became increasingly conditional in their resp onse, wanting quality to be assured and expressing co n cern for safe ty. The follow in g comments are examples of th e differing remarks made by respondents w hen questioned about using recycled water for cloches washing: • 'Not clothes washing, I would need more information,' • 'Don't like that idea, some water can affect the washing eg smell,' and • 'Not entirely suitable particularly for people with babies' and • ' It might be nicer than river water' For drinking, the fo llowing responses are examples of comments made; • 'it depends on the treatment and controls in place,' • ' I don't know enough about the quality, a bit iffy,' and

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Results Population sample

When compared with Australian Bureau of statistics data, results indicated the Mawson Lakes population was representative of the gene ral Australian population, that is, they are the same with regard co their attitudes co w ater conserva ti o n and ge n e ral issues and are representative of middle class Australian income and education. When questioned about their choice co live at Mawson Lakes, close location co wetlands and parks was found to be the biggest contributing factor. The dual water supply system ranked 11 ch of 12 facto rs contributing to the respondents choice co

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• 'I'm worried about the health risks.' Results also indicated strong trends between diffe rent age groups which has significant implications in terms of policy. The Age Attribute

Drlnkl g

Each respondent was grouped into one of the fo llowing categories by age; 18-30, 31-50, and 51+. There were a number of strong trends observed between different age groups with som e significant Figure 2. Support for water reuse - decreases as differences. T h ese t rend s for proposed use becomes increasingly personal. different age groups have implications for and give indications to so than the older respondents. This water policy developers. The trends indicates that younger people will be more observed between age groups are discussed willing to live in suburbs with ESD in the following paragraphs, and inferences fea tures. Housing developers may find this abou t implications for water policy develinformation useful for the marketing of opment are made. their housing developments. They may As mentioned above, support for water also consider installing ESD features, to attract younger custom ers and first home recycling immediately felJ as a particular use was specified . This fall in support is buyers. displayed in Figure 3. This graph displays • Younger respondents more strongly the mean sco res of responses for each age disagreed w ith the statement 'there is no group when asked abo ut their attitudes to reason to save water.' This indi cates younger respondents had a greater undervarious proposed uses fo r reclaimed water. sta nding of the need to conserve water. In this graph, 1 = excelJent, 2 = ve1y good, This alerts water policy developers to target 3 = good , 4 = ok, 5 = not sure, 6 = don't water conservation edu cation campaigns like it, and 7 = defi nitely not. Th e to older age groups. difference in the mean response fo r each • Youn ge r respo n dents were mor e proposed use is statistically significant. This supportive of the use of recycled water for graph also displays the slight difference potable purposes in future , providing found between the responses of differing appropriate quality is guaranteed. This age groups. indicates yo unger people will be more • Younger respondents agreed more receptive of potable reclaimed water use, strongly that environmental benefits of the perhaps having a greater trust in dual water supply are more important than technology. This is important for water financial benefits. T here was a statistically policy developers to note, as potable reuse significant difference between the responses or partial potable reuse (ie the topping up of each age group to this question. This of potable reservoirs with reclaimed indicates younger people may be more water, as commencing in Singapore) may wilJing to pay for reclaimed water. This is particularly importan t when assessing the feasibility of a proposed dual water system, for which the initial infrastructure costs are often ve1y expensive. Recla imed water for dua l suppli es has been delivered at 80% to 100% of the cost of potable water in most examples throughout the world. These results may indicate the likely willingness of different m embers of the community to pay 80% to 100% of the cost of potable water - for water that is of a lesser quality. • T he potential to do som ething positive for the environment m otivated younger respo ndents to live at Mawson Lakes, more 48

WATER AUGUST 2003

become an increasingly necessa ry development. •Younger respondents were more concerned with environmental problems . This may indicate younger people will be more willing to accept new technologies 0.7% and developments if they are in aid of producing a better environmental outcome. This may also indicate to policy developers that exp lain ing the environmen tal necessity/ b en efit of reuse is necessary when introducing dual water supply systems to new areas. • A higher number of respondents in the 50+ category rated health as the most important issue facing society, this decreased with age. This demonstrates the differing prioritisation of issues between age groups. • Respondents in the 18-30 age group rated the Mawson Lakes Development's foc us on environmental sustainability 6th, energy efficiency 4th , and the dual water system 9th, as factors contributing to their choice to live at Mawson Lakes. These rankings were h igher than older age groups.

Conclusion

Results indicate the greatest opposition to water reuse schemes wilJ come from those over the age of 50, indicating this age group should be targeted fo r education and information campaigns in the case where water reuse schemes are being introduced. Results indicate those under the age of 30 are more receptive to reclaimed water use, are more supportive of reclaimed water use for drinking purposes in the futu re, are more concerned about environmental problems, see a greater importance for water conservation, and have a greater un derstanding of wate r reuse schemes. 7 Support for reclaimed water 6 use significantly decreased as the proposed use became increas5 ingly personal, with 99% of ::, respondent supporting the use of "'C:> 4 reclaimed water fo r lawn "'Q) 3 E irrigation, 49% supporting the 2 use o f reclaimed water for clothes was hing, and 0.7% 1 supporting the use of reclaimed 0 water for drinking purposes. ·-§:-~ ~<::-~~ 18-30 ~ R esults suggest that the Mawson ,:,.'l> ~ ",,; .if ~'Ii ~ 31-50 ~ Lakes population is positive <o ~'l, about the immanent reclaimed 51+ ~ water use for non-po table uses. R esu lts suggest that the Figure 3. Attitude to use of recla imed water for various population is not yet prepared to proposed uses - comparison of age groups. accept reclaimed water use for Va lues range: 1 = excellent to 7 = definitely not. Q)


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potable purposes. Responses to attitudinal statem ents suggest that you nger respondents vvould be more willi ng to accept reclaimed water use for drinking purposes. The results of th is benchmark survey provide interesting information for water policy developers. The second part of this study w ill involve th e monitoring of reclaimed water use and fu rth er survey of the population once the reclaimed water su pply commences d istribu tion. The results o f this study will provide further valuable inform ation fo r water policy developers and industry professionals.

Acknowledgements T he au thors thank the following people an d organisations for their assistance and in terest in our resea rch; C hris M ari es, Dr Stan Salagaras, Delfin Lend Lease Li mited, the C ity of Salisb ury, Professor Phil H owlett, D r J ohn Boland, and the Marketing Science Centre.

The Authors Jennifer McKay 1s a Professor of Business Law , and Director of the Water Poli cy and Law Group, University of South Aust r a lia (E mai l : jennifer.mckay@un isa.ed u. au ). Anna

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Hurlimann is a PhD ca ndidate and a m ember of the Water Policy and Law Group (h ttp:/ /b usiness. unisa .edu.au/ wa terp o li cy law) at the School of International B usiness, University of South Australia, North T ee, Adelaide, SA, 5000 (Ema il : hurac00l@s tu dents. unisa.edu.au).

References Anderson, J. M. (1996) . "Current Water Recycling Initiatives in AustraLia: Scenarios for the 21st Cencu1y." Water Scie11ce a11d Tech11ology 33 (10-11) : 37-43. Bru vold, W. H. (1979). P11blic Attit11des To111ards Co1111111111ity Wastewater Recla111atio11 a11d Rmse Optio11s. California, Uni versity of California . Byrnes, P. (2000). Re11se i11 Cal!foniia - n11 A11stmlia11 Perspective. Water R.ecycling Australia, Adelaide, CS IRO & AWA. Dillon, P. (2001). "Water R euse in Australia: Curren t, Futu re and R esearch." vVater: 28, 3 Hamnet, S. (1998). The Adelaide M11lti-F1111crio11 Polis: from Sere11dipity Cit)' to Medi11111 De11sit)' S11b11rb. 8th Internacional Planning Hisco,y Conference, Sydney. Irvine Ranch Water District (1994) . Water R eclamation and R euse: An Exemplary Program . Irvine, Irvine 11..anch Water District: -1-. Jeffrey, P. and B. Jefferson (2001). "Water R ecycling: How Feasible Is It?" Filtmticm a11d Sepamtio11.

Law, I. B. (1996) . "Rouse Hill - Australia's First Full Scale Domestic Non-Potable Reuse Application." Water Scie11ce and Tec/1110/ogy 33 (10-11) : 71-78 . Marks, R. (2000). In n ovation in Water R ecycling. Water Se11sitive Urba11 Desig11 I,ifor111atio11 S011rce CD ROM. M . Water. Melbourne, Melbourne Water. New South Wales Government (2003). Recycled Water at H ome . Newi n gton, Wa ter R ecla mati on and Management Scheme Project Office: 3. Nexus Australia (1999). Education Needs Background R eport. Brisbane, Queensland Water R ecycling Strategy, Queensland Government. Okun, D. A. (2002). "Water reuse introduces the need ro integrate both water supply and was tewate r management at local and regulatory levels." ltVater Scie11re mid Ted111ology 46 (6-7): 273-280. Parker, P. (1998). The M1tlti-F1111ctio11 Polis 19871997: a11 l11tematicmal Fnil11re or l1111011ative Local Project? Waterloo, Austra lian-Japanese Research Centre. Taylor, E. (2003) . http://www.abc.nct.au/ science/slab/ olympics/default.hem. 2003. Wolff, G . and P. H. Gleick (2002) . T he Soft Path for Water. Tl,e World's Water 2002-2003: Tl,e Bie1mial R eport 011 Fresh Water Reso11rces. P. H. Gleick. Covelo, Califo rnia, Island Press: 1-32 . Young, R. E. (1989) . Irvine R anch Water R eclamation Expands. Irvine, Irvine R.anch Water D istrict: 8.

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MANAGEMENT PROGRAM HELPS BUSINESSES SAVE WATER IN WA M Viskovich, S Moulder Abstract

The Water Corporation wan ted to facilitate sustainable To address sustainable water impr oveme nt s in water conse r vatio n the Water Conduct Water Audit Time for Another Audit managem ent with their industrial Corporation of Western Australia +5 and commercial customers. Max is rolling out an innovative water Viskovich , M anager Business managem ent program with its 0 R elati onsh ips at th e W ate r comme r ci al a n d industrial Corporation , identified that "a custom ers, based on a successful -5 good water efficiency program -::f!. pilot program. This article details 0 Water Management involved educating and involving Cll Program Falter s Back the drivers for water conservation -10 employees, locating all waterto 'Business as Usual' Cll in W es tern Australia, the tradiC using sources and identifyi ng (J tion al approa c h to water -15 and impl em enting sustainable c onse rvat i on, the W ate r water management systems." The Corporation's pilot program , th e Wa ter Corporation was seeking -20 findings and solution. an approach that addressed fou r specifi c objectives: Background -25 years 0 1 2 3 4 5 6 7 8 9 1 0 r,• Driving sustainable improveT he W.A.State Water Strategy m ents in water conserva tio n (February 2003) stated that Figure 1. Traditional business approach to water • Partnering with customers o n "Prooramsfiocusino on water e_[ftcie11cy 6 <> cons ervation. water conservation in the commercial and industrial sectors • Developing and maintaining are not well established in Weste rn increase. The audit uncovers cost-saving strong relations with business customers Australia" (page 24). It calls fo r strong opportunities, some of which are imple• Adding value to business custom ers community, government and industry mented. T he Australian fi rm Energetics partnerships to ensure a sustainable water Pty Ltd has identified that a number of The Water Corporation's future for Western Australia. opp ortunities are missed w hen audits are Proposed Solution The Water Corporation recognises th e not supported by other managem ent In addition to the market research importance of water efficiency and sets a pra ctices. After a few years the focus above, the W ater Corporation discussed key focus on wa ter conservation . It has usually m oves from water onto another identified a water management diagnostic set a high priority on encouraging water business issue (e.g. quality, waste), water tool, W ater Achiever®, developed by use effic ie ncy as part of its drive to build costs rise again, m anagement requests E nergetics Pty Ltd, that has already been robust relationships w ith its key business another audit and the cycle continues (see market-tested and adopted by Sydney Figure 1). customers. To reach this objective the Water. W ater Corpo ration conducted broad Some of the reasons for limited impleresearch. During this research more than Pilot Program mentation fro m audits conducted by 40 water-related web sites were located themselves include: In February this year th e W ater and considered. One of the best was • Audit is a "snap shot". There is no onCorporation conducted a pilot program presented by the N orth Carolina going responsibility fo r water or driving using the water management diagnostic D epartment of Environment and Natural fo rce for improving water management approach w ith five n1ajor custom ers fr om R esources in the U S. This included a 49different industry sectors; hospitality, • Lack of water conservation awareness point water conservation checklist fo r health, food and beverage, retail and amongst employees offices and buildings including immediate government. T he pilot program w as • Limited management awareness and co nservati on options and long-term designed to assess the value of th e water therefore commitment to implement the actions. management diagnostic approac h, gain audit findings business customer feedback and identify Traditional Approach to Water • Audit solely focuses on cost drivers. specific areas where customers needed Conservation Other business drivers such as producsupport. It involved conducting water ti vity, su stainability, an d co rporate The traditional approach to water management diagnostics at customer citizenship drivers are not given adequate premises w ith the customer's se ni or management w ithin businesses has been weight in the decision-making process. to co nduct an audit when water costs management teams . Traditional Approach to Managing Water

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Methodology The managem ent diagnostic approach addresses water management as a business management issue, rather than as a technical engineering issue . It is applied th rou gh a dynam ic self-assessment workshop with the customer 's senior management team, ryp ically the business manager, operations manager, fi nance manager, m aintenance and engineering manager. A diagn ostic session involves asking a structured series ofYes/No statements that the managem ent team uses to eva lua t e th e ir cu r rent water m anage m ent p ra ctices . It is based on a proven m ethod o logy that exam ines k ey a r eas of a n e ffec t ive water management system . O nc e the m anagem en t team has completed th e diagnostic, the software prov ide s th em with an immed iate management report at the end of a onehou r session, w hich includes: • Complete assessment o f their cu rrent status of water m anagem ent

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• I de ntifi cation of st re n gt hs and weaknesses in t heir curre nt water managem ent practices • Prioritise d actio ns for imm ediate improvem ent Importantly, the actions are achievable steps that can be implem ented withi n a short-term timeframe and direct the business to integrate water into their existing management systems. The tool includes a plan ning module to gain con1.mitment to actions, respons i bi lit i es a nd ti m e fram es fo r implem entation.

Pilot Program Results All customers in the pi lot program wa nted to continue to work w ith the W ater Corporation using th e water managem ent diagnostic approach to add val ue to their business. Additionally all custom ers recommended the process to others b usinesses in their industry. A su mmary of customer fee dba c k is provided in Figure 3. O th er specifi c feedback and requests from customers inclu ded:

• Contin uing the partnership w ith the Water Corporation and provision of fo rmation/strategies to improve water consumption • Ideas to improve water usage at the sa m e ti me as " d o good" for the environment • Easy to understand system with clear, easy to follow instructio ns • R aised awareness of issues that had not been considered prior • Exposed gaps in work to date and opportu nities to enhance & increase efforts Findings of th e pilot program also indicated th at customers needed m ost support in th e areas of awa reness and trai ning, leadership, accountabi lities and innovation.

Roll-Out Program Following the successful pilot program, th e Water Corp oration has design ed a water managem ent program to facili tate sustainable water use within industrial and com mercial customers. The program is designed to help the customers integrate

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water into their existing business systems such as quality and environmental systems, drive continuous improvement and achieve sustainable reductions in water usage. It incorporates responses to the areas identified in the pilot program where customers most need support. T he roll-out program is based around three key components: • A partnering agreem ent with a clear and transparent understanding of actions and timeframes that both the Water Corporation and the business agree to take • A water managemen t diagnostic (Water Achiever®) facilitated by Water Corporation staff to identify and address m anage m e n t b arr i e r s t o water man ageme n t. Th e management diagnostic identifies priority specific actions and links the actions to the Water Corporation's support services • A range o f support services that are tailored to individual customer needs, as identified through the managem ent diagnostic, such as water man agement guidelines, case studies and implementation tools. One of the key factors in selecting the management diagnostic approach was that it w as easy to use by the W ater C orporation's Business R elatio nship Managers, who didn't need assistance by external consultants to introdu ce th e p rogram to their customers , thu s redu cing the cost of implementation.

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Figure 2. Water management diagnostic methodology.

The Water Corporation's program is building pro-active partnerships with c ustomers t h at work towards achieveme nt of commo n goals. It is achieving thi s through strong relatio nshi ps wit h its c us t o m e r' s senior m anagement teams.

management and allow the Water Corporation to work with and add value to their business custom ers on an ongoing basis (see Figure 2).

Conclusion The Water Corporation is now rolling out a water management program with its commerc ial and industrial customers. T he program is stru ctured around a managen1ent diagnostic that assesses a customer' s current water managem ent practi ces and identifies priority actions for improvement. The diagnostic links the customer's priority actions to the Water Corporation's services. The program provides the customer with manageable steps for improving water efficiency and pathway to continuous improvement.

Continuous Improvement The process is designed to be repeated on a 12 -monthly basis t o dri ve continuous improvement in water

The Authors Max Viskovich is Manager, Business Re l at i onships for t h e Wate r Corporation, (08) 9420 3881, email max. viskovich@watercorporation.com. au. Stuart Moulder is Business Manager, New Products for E nergetics P ty Ltd, (02) 9929 3911, email moulders@energetics.com.au

Wa ter Acliie11e1® is a registered trademark of Energetics Pty Ltd.

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expected to be up to 30% cheaper than one installed with the technology available in 1994 w hen Australia's first major m embrane reuse plant at Eraring Powe r Station opened. Th e latest in a number of municipal wastewater reuse plants to be built in Aus tr al ia , the Kwinan a Water R eclamation Plant (KWRP) w ill be located in the industrial belt so uth of Perth, WA. Veolia Water Systems secured the project for the W ater Corporation of WA in a joint ve nture with John Holland. The plant will use th e dual membran e technology of microfiltration and R everse Osm os is to recycle water from the nearby Woodman Point Wastewater T reatment Plan t (WWTP) and provide

high quality water for large industria l custom ers such as Rio T in to, Ediso n Mission Power and petroleum giant BP. These represent the largest single users of Perth's public water supply, helping th e WA Government achi eve its goal to reuse 20% of treated wastewater by 2012 (T able 1 and Fi gure 1).

R e using sewage effluent isn't a new concept, but never has it been more comm.ercially viable than it is today. For years recycling has been mooted as an impo rtant element in th e quest for water co nservation, particularly for drought-prone Australia. In fact, reuse The Kwinana WRP Process oppo rtunities are now in vestigated as a matter of course for medium to large Submerged Microfiltration wastewate r treatment plant upgrade Efflu en t from Woodman P o int projects . Not surprising w hen you WWTP is pumped to a 280 1113 contact consider the recent developments in tank on the KWRP site. Th e efflu ent is microfiltration/Reverse Osmosis (R O), pre-screened to a level of 2mm, then the industry standard for water recladosed with sodium hypochlorite to form mation from treated effluent (partic ularly a chloramine residual to control biological fo r industrial custo mers) which was fouling on the microfiltration and R everse developed by Memtec Ltd (now Memcor Osmosis (RO) membranes. A Australia, a division of the small quanti ty of su lphuri c acid Ve o l i a Envi r o nnement is also dosed to the feedwa ter to Table 1. Kwinana WRP at a glance. grou p). sli ghtl y reduce pH for more Advancements 111 Parameter Value favourable conditions for the m e mbr a n e technology, downstream R everse Osmosis KWRP Feed Flow 22.2 ML/day coupled with the lessons learnt system. from the past 20 years of Feed water quality 850 mg/L TDS average Screened , dose d e fflu ent applying m embranes to the No CMF-S Cell s 4 x 33% (288 membrane modules) flo ws under gravity to four treatment of mun i cip al Microfilter Recovery 90% id e nti ca l Submerged was tewater, has crea ted a SDI <3 Microfilter Filtrate quality Continuous Microfiltration cells m ore sop h is ti cat ed and Tot Coliforms <1/100mL (C MF -S) whic h al low s chea per process. A du al No RO Units 6 x 20% (210 membranes per t rain) continuous filtration of th e membrane reuse plant RO Recovery 80% effluent to 0.2 micron. The installed today, such as the sys t em uses ho llow fibre K winana Water R eclamation RO Permeate flow 16.7 ML/day m embranes to produce high Plant (KWRP ) curr en tl y RO Permeate quality <50 mg/L under co n str u ct i on, i s quality treated wate r, and WATER AUGUST 2003

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Conce ntrate waste fr om the concentrates removed particles Table 2. Eraring WRP at a glance. R O trains is coll ected and for disposal. returned to th e o utfall line. Value Parameter Mi crofiltration provides a T he co n c en tr a t i on of co nsi ste n tly hi gh feed wat er WRP Feed Flow 3.75 Ml / day dissolved salts inc reases across quality for the dow nstrea m Feed water quality 721 mg/l TDS the RO membranes. W ithou t R everse O sm osis m embrane 2 x 90 module units No CMF Units proper chemical conditioning, treatment . In fac t, th e use of 90% Microfilter Recovery some o f these salts w ill become mic rofi ltrat io n en ables t h e supersaturated and precipitate on Microfilte r Filt rate quality SDI <3 R everse O smosis m embrane to th e membrane surface . T he s u p p l i ers t o p r ovid e a n Tot Coliforms < 1/ 100ml feedwater is condi tioned by additio nal two years on top of Reverse Osmosis Units 2 x 50% 63 membranes per t rain dosing a ch emi cal antiscalan t their no rmal three year pro-rata RO Recovery 80% which prevents the precipiwarranty, significantly redu cing RO Permeate flow 2 .50 Ml / day of these sparingly soluble tation co sts in me mb rane replaceRO Permeate quality <61 mg/ l salts. m ents . Each C MF-S cell houses Permeate Treatment Table 3. Eraring cost compari son. 288 membrane submodules mounted RO m embranes remove the in racks with each rack containing majority of dissolved salts from Eraring at 1994 Eraring If Built Today 36 m embrane submodules suspended a solution , but they are not able to A$3 .3 M * A$2 .5 M (est)* in feedwater. Each submodule in r e m ove di ss ol ve d gases . turn houses a bu ndle of 0.2 micron Consequen tly, R O permeate has a * Not including civil costs at 2003 prices hollow fibre m embranes. W ater is relatively high concentration of drawn through the walls of the C O 2 . A degassing tower removes the approximately three hours to complete . hollow fibres under vacuum by a filtration C O 2 to raise the pH w itho ut the need fo r T he membran es are cleaned by re-circupu mp. ch em ical dosing. Water is fed to the top lati on with a heated weak acid or of the degasser where it is distributed over Filt rate fr o m th e fil trate p u mps caustic/ detergent soluti on. a bed of d ump-fill pl astic packing. As combi nes in a common header and is water percolates downwards th rough directed to the 6501113 reverse osmosis feed Reverse Osmosis the degasse r tower packing it contacts an tank. Each R everse Osmosis (RO) train upward flow of air (the pac king is comprises two stages of R O m embranes. T he drivin g pressure increases as designed to enhance the contact betw een Feedwater is pumped at high pressure into parti cles build up on the m emb rane air and water). T he air strips CO2 from the fi rst stage and flows along the tub es surface during fi ltration. T o m aintain the the water, raising its pH. T he degassed and across the su rface o f the R O required flow-rate, these particles must be water flows under gravity to storage from m embranes. Approximately 55% of the remo ved. T he backwash cycle forces air w here it is chlorinated and distributed to feedwater is recovered in the first stage aro und the walls of the membranes from vario us Kw inana WRP customers. inside each bundle to dislodge the buildas permeate . up. Filtrate flows backwards through the m odules to help carry the dislodged particles from the membrane elem ents. E ach C M F-S cell requires regular cleani ng every fo rtn ight to ensure longterm stable operatio n. C lean In Place (C IP) is an au tomated process taki ng

T he concentrated waste stream fro m the first stage flows to a small er, second stage w here a fur ther 25% o f the feedwater is recovered. Permeate fro m each RO train is coll ected in a single header and runs via a degasser and hypoc hlorite dosing to sto rage .

Nett Installed MF Capacity

1994

1995

1996

1997

1998 Year

Figure 2. Net installed capacity of microfiltration.

54

WATER AUGUST 2003

1999

2000

2001

2002

Eraring Power Station, NSW Water Reclamation Plant design nine years on The major advances in dual membrane W ater R eclamation Plant (WRP) design are evident w hen comparing Kwinana to the reuse plant at Eraring Power Station, built in 1994. T he 2.8 million litre p er day WRP at E raring Power Station, located on NSW's Central C oast, pio neered the use of m embrane tech nology on an industrial scale fo r wastew ater recycling (T able 2) . Eraring identified the p otential fo r reuse in the early 1990s when a new sewage trea tment plant at nearby Dora C reek was op ened by the H unter W ater Corporation. The installation o f a dual m embrane system enabled secondary sewage from D o ra C reek to be trea ted and recycled into high q uality feed water. Th e dual m em b rane sys tem w as commissioned in October 1994 and, as of December 2000, had produced almost 3, 100 ML of reclain,ed effl uent fo r the power stati on.


WATER If the Eraring WRP was built today, it would be cheape r to construct and operate. Based on tec hnological advan cements since 1994, it is Veolia Water System Australia's estimate that the Eraring WRP would be a full one quarter less expensive in terms of capital costs (T able 3).

REUSE

Du e to mi crofi ltrati on plants in creasing in size, there is now greater foc us on minimising the cost Pressurised CMF Submerged CMF of the non-membrane component of the MF system, in particular ancilA$1. 78M (est) A$1 .35M (est) laries such as membrane manifolds and housings. Submerged membrane Table 5. Cost comparison between pressurised systems enable a large m embrane and submerged CMF. inven tory to be housed in a very small space. These systems have also Pressurised CMF Submerged CMF Microfiltration Advances achieved a redu ction of around A$0.124/ kl (est ) A$0.092/ kl (est) Mi crofiltration tec hno logy has 80% in valves and seals. Initially grown exponentia lly in the last env isage d for la rge r syste m s, decade . When Eraring was com missubmerged microfiltration is proving systems compnsmg skid mounted unit sio ned in 1994 th ere were approximately to be m ore economical even in small-scale con figu rations of aro u nd 90 - 100 2 50 plants in th e world w ith an average installations. A submerged microfiltration membranes per unit. T h e m embranes capacity of0.2 ML/day . T o day, the re are were supplie d in a pressure vessel, all of plant of E raring's size would be approxmore than 1000 rnicrofi.ltration plants w ith imately 25% less expensive in terms of which were conn ected in an array. an average capacity of more than 3 Driving pressure was supplied to the arrays c apita l c o st s (n o t i n cludi n g c ivil M L/ da y (Figure 2). There are m o re than usually fro m feed pumps and in some cases constru ction) if built today (T ables 4 and 60 plan ts worldw ide w ith a capac ity by gravity. 5). greater than 10 M L/d. The largest, at 325 M L/d, is Table 6. Operating pressure advantages of TFC membranes. unde r c ur r ent l y co nstruc tio n. Project Design Conditions Membrane Op. Pressure U ntil recen tly, m an y 3. 75M L/ day Eraring Power Station 720mg/ L TDS @ 80% recovery CA 30 bar m icrofiltration m em branes 850mg/ L TDS @ 80% recovery 1 6.7 ML/ day Kwinana TFC 13 bar w ere supplied as pressurised Table 4. Cost comparison between pressurised and submerged CMF.

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WATER

REUSE

The submerged microflltration plant at Kranji, Singapore.

The following fac tors have helped reduce the cost of microfiltration systems: • Increased membrane life (reduced life cycle costs). • Manufacturer cost savings due to increased production volumes. • Lower ancillaty costs as larger membrane quantities are fitted into single filte r units. • Increased competition . O perating costs has also fallen by moving to submerged microfiltration due to lower pump operating pressures, and r ed u cing cleaning chemical consumption. Developments in RO Membrane Technology

Although Reverse Osmosis is a more mature technology than microfiltration (the fi rst plants were installed 30 years ago), it has grown significa ntly in the past decade. C apital and operating costs have dropped while system reliability and performance have improved. Low Fouling Composi te Membranes

Film Composite (TFC) membranes, including: • Lower operating pressures. • Improved Salt Rejection. • W ide operating pH range. • Lower costs. The extent of the operating pressure advantages of T FC membranes is clear from Table 6. Im proveme n ts are ongoing as membrane manufacturers work to differentiate their products in a competitive market. Two major changes over the past 10 years include: • A 20% increase in surface area per membrane (Up from 365 ft 2 to 400 ft2). • The advent of automation in membrane assembly, leading co higher quality and cheaper manu factu re. Control of Membrane Fouling

One of the greatest concerns in using membranes in wastewater application is membrane fouling - biological fouling and also fo uling fro m the precipitation of phosphate salts. Biological fouling at reuse applications is overcome with the use of chloramines.

Municipal wastewater reuse has been the largest growth area for RO. To be successful in this application, membranes need to contend with the feed water's fo uling nature. Cellulose Acetate (CA) membranes have been traditionally used in this application (as they are at Eraring) due to a high chlorine tolerance. H owever, extensive research into the types and causes of bio-fouling has seen the development of fo uling resistant composite membranes which ex hibit stable and reliable performance . Systems now enj oy the advantages of T hin RO installation at Bedok, Singapore. 56

WATER AUGUST 2003

Monochloramine (NH2CJ) is used extensively as disinfection instead of chlorine in many mu nicipal drinking water applications. In secondaty effluent, there is often ammonia present which , upon contact with chlorine, will form chloramines . Chloramine is an effective disinfectant which significa ntly decreases the frequency of chemical cleaning of microfiltratio n and RO memb ranes without causing any damage that disinfection with chlorine alone may cause to MF and RO membrane materials. Chloramination also helps to prevent mineral scaling. In some cases w here biological fou ling has upset the flow balance of a mem brane array, low concentrate flows in some membrane casings create conditions that result in scaling precipitates. By p reventing the biological fouling, chloramination avoids this problem. At Kwinana WRP, particular attention was paid to selecting an antiscalant for its ability to prevent calcium phosphate scaling. This was of particular concern as the Woodman Point WWTP does not remove ph ospho ru s to avoid scal e formation at the sewage plant. Based on experience fro m wo rk done by Veolia Water at membrane plants in Singapore, and in technical discussion with chemical suppliers, an antiscalant in combination with pH correction was selected to allow concentrations of phosphate up to 13. 0 mg/ L (as P ) to contact the membranes without resulting in scale formation.

Conclusion Effluent recycling using microfiltration and R everse Osmosis (R O) has made significant strides up the learning curve, w hile coming down substantially in costs since Eraring opened almost 10 years' ago. As membranes have become cheaper to install and to operate, reuse applications which were once considered marginal, today signify a responsible commitment to sustainable development as well as good commercial sense. Kwinana W R P is j ust the latest in what Veolia Water Systems Australia expects will be a long list of future reuse plants.

Author Troy Walker is Process D esign Coordinator, Veolia Water Systems Australia, email tw alk er@vivendiwa ter.com. au.


a

WASTEWATER

BIOSOLIDS TO LAND: INTERNATIONAL REGULATIONS PART II: PATHOGENS

-

H Reid, A Savage Abstract This paper is the second of a two part series exploring the b iosolids regulatory frameworks in th e United States and Europe and contrasting these frameworks with the Australian approaches. As previously described, land application of biosolids (loosely defined here as appropriately treated sewage sludge) has demonstrated beneficial outcomes and has been a long established and widely adopted acti vity. However, to e nsu re appropriate management of any associated risks, it is a practice that is almost uni versa lly subject to regulatory oversight. The focus of th is paper is the management of risks from pathogenic o rganisms, complimen ti ng the previous paper that focused on inorganic and organi c contaminants. W ith in recent years there have been significant initiatives w ithin the United States, European and Australian biosolids regulato1y frameworks. Understanding the potential significa n ce of these changes is of obvious importance to Australian biosolids management programs. In 2002, the National Research Council in the United States (US) finalised their 18month review of the scientifi c basis for the regu latory requirements for biosolids in the United States. Although this review did not find evidence that the US regulato1y framework was inappropriate, it did make a number of recom m endations for updating the scientific basis for the regulations and the need for greater US E n vironment P rotection Agency (U S EPA) oversight of biosolids management. Si multaneously with th is ac ti vity in the US, the European Comm.ission (EC) began redrafting their sl ud ge management directive (86/278/EEC) and have progressed to a third worki ng draft. In Australia, the draft of the Natio nal guideline Draft Guidelines

for Sewerage Ma11age111e11/ - Biosolids Ma11age111en1 was released for pu blic consultation under the National Water Quality M anagem ent Strategy, in May 2002.

Although there are some similarities in the regulatory approaches that are taken for managing pathogen 1isks, there are also important differences. T here is general consistency in the treatment processes that are used fo r classifyi ng treatment grades and consiste ncy in the organisms that are used for process monitoring. However, there are sign ificant differences in the quantitative microbiological criteria that are applied and in the criteria used to verify technologies.

Overview of regulatory programs and land application As with the previous paper ( Water, D ecember 2002), a loose definition of biosolids is used - sewage sludge that has been treated and has su fficiently low levels of pathogens and chemi cal contaminants, such that it can be safely used for land appli cation. Sewage sludge with inadequ a t e treatment or excessive contam ination is not considered suitabl e for land appl ication and hence is not included within the definition ofbiosolids. A ' loose' defi nition is used, because the actual definiti ons of qualitative statements such as 'inadequate treatment' vary amongst regu latory approaches. United States In the United States, the overarching regulato1y fra m ework fo r land application is under the Code of Federal Regulations 40 Part 503. This is the so-called 'Part 503 rule', a regul atory framework that was promulgated in 1993. The key sections of the regulations specify requirements fo r contaminants, pathogens and m easures to avoid attracting vectors (such as insects and rodents) to land application sites. The 503 rule manages potential pathogen risks by combini ng prescribed treatment t ec hnol og ies and mic r obiologica l standards to de ri ve two treatment grades (Class A and B) (Vesili nd and Spi nosa, 2001) . Class A biosolids are considered suitable for unrestri cted use from a mi crobiological perspective, w hile Class B biosolids ha ve restrictions on land use post appl ication.

Annu al sewage sludge production in the United States is approx imately 5.6 million dry tonnes, with around 60% of this productio n used as soil amendments and/or fert ilizers (NRC, 2002). Europe

At the Eu ropean Commission level, the key direc ti ve for biosol id s management is 86/278/EE C 'for the protection of the environment and in particular soil' from the use of sewage sludge. T his directive includes quantitati ve lim its on con taminant levels in biosoli ds and soils. However it doesn 't provide definitive direction on the management of pa thogens through t reatment, providing only qua li tative gui dance that sludge needs to be treated " ... to redu ce its fermentab ilit y and the h ea lth hazards ... " . The directive includes defined restrictions on biosolids use, but there is no provision for an ' unrestricted use' of biosolids (this presumably reflects the lack of a defined highl y treated bi osolids grade). Th e directive is currently being redrafted and the third working redraft of the directive describes prescribed treatments and mi crob iological criteria. Although member states are required to implemen t EC directives into their regulatory programs, the lack of defi nitive EC treatment requirements has resu lted in signifi can t differences in the requirements imposed at a state level. As described in the previous paper, there are also significant differences in the philosophies and acceptan ce of biosolids la nd appli catio n between m ember sta tes. Extremes of this are illustrated by the apparent broad support for land applicat i on 111 the UK, and the recommendations agni11st biosolids use from the Swedish Federation of Farmers (EC, 200 1). The 15 European Member States are estimated to have an annual sewage sludge producti on of 7 million dry tonnes. Germany is the leading produ cer w ith approximately 2.2 million dry tonnes, fo llowed by the UK, France, Italy and Spain (EC, 2001). WATER AUG UST 2003

57


WASTEWATER

Australia

Within Australia, regulatory oversight of biosolids management is primarily the responsibility of individual states and territories. However, a draft national guideline (National Water Q uality Management Strategy (NWQMS): Draft Cuidelinesfor Sewerage Ma11age111rnt - Bio so lids Ma11age111e11t) was distributed for public comment in May of last year. The draft guideline defines three pathogen grades (Pl, P2 and P3), which are based on prescribed treatment processes and microbiological standards. It also details vector attraction reduction measures. Grade Pl biosolids are considered suitable for unrestricted use, and grades P2 and P3 have increasing degrees of enduse restriction. In lieu of the national guideline, the most widely referenced guidance appears to be the New South Wales EPA guideline, which exhibits some differences to the draft national guideline (NSW EPA, 1997) . The Tasmanian (DPIWE, 1999) and Sou th Australian guidelines (SA EPA, 1996) most closely align with the NSW approach, while the recent Western Australian guideline (DEP, 2002) and the consultation draft of Victoria's guideline (EPA Victoria, 2002) are aligned with the draft national guidance. As illustrated in WSAAfacts (2001), the proportion of sewage sludge production that is beneficially used as biosolids varies between States and the individual water businesses. Amongst the major water businesses, ACTEW Corporation and Sydney Water reported close to 100% biosolids reuse in 2000/2001, SA Water Corporation reported 152% reuse (due to use of existing stockpiles), while the Western Australian Water Corporation and Me lbourne Wa ter Corporation reported 70% and 8% reuse respectively.

Regulatory approaches to pathogen management Given the significant differences that exist in the international regulation of inorganic and organic contaminants in biosolids (Reid, 2002), it cou ld be considered a surprise that there is a reasonable level of consistency in the approaches to microbiological classification of biosolids . The majority of regulatory approaches (but not all) currently have the following areas of consistency: J. classification is based on a philosophy of combining prescriptive treatment processes with microbiological criteria, for example E. coli per gram biosolids; 2. simila r treatme n t processes are described, for exampl e mesophili c 58

WATER AUGUST 2003

anaerobic digestion and composting; and 3. classification involves a two level system with a 'high quality' and often unrestricted use grade biosolids based on intensive treatment, and a 'base' or restricted grade of biosolids based on relatively standard approaches such as anaerobic mesophilic digestion. Material that is raw or inadequately treated fo r the above classification is typically considered unsuitable for land application. These similarities possibly refl ect the der ivation o f the microo r gan ism management approaches, which appear to have evolved from a reliance on historical practice, available technologies and professional judgement. It is only relatively recently that quantitative risk assessment m ethods have begun to be appli ed. However, while there are some important similarities, there are also signifi cant differences in the way regulatory approaches address microbiological issues.

'Intensive treatment' grades The terminology 'intensive treatment' grade is used in this paper to describe the highest classifi cation grades described by the different regulatory authorities. This descriptor is used because each regulatory authority adopts different nomenclatu re (for example 'Class A' in the US, 'enhanced treatment' in the UK, 'P1' in the draft national Australian guideline), and so the specific nomenclature is reserved for discussions of the relevant regulatory authority. In addition to the follow ing text, the requ irements of the different jurisdictions for achieving an 'intensive treatment' grade biosolids produ ct are summarised in table 1.

United States The pathogen standards for the US 503 rule were based on operational experience and professional judgement, rather than a fo rmal risk assessment process (Hay, 1996) . The regulatory approach to classification is predominantly based on the previously described combination of va l idated tech n ologies, ongo i ng monitoring of process control parameters and compliance with bacterial limits. The valid treatment processes include processes that conform to generic temperature-time curves, specific pH-temperature-time criteria, processes that are listed in the regulations as Processes to Further Reduce Pathogens (PFRPs), or processes that have been mor e recently assessed and considered as 'equivalent' to PFRPs. The PFRP equivalent processes tend to be strongly focused on proprieta1y processes rather than generic descriptors. A recent addition includes a proprietary two-

stage Autothermal Thermophilic Aerobic Digestion p rocess (US EPA, 1999; NRC, 2002) . To be classified as Class A biosolids, the treatment process must operate within defi ned specifications and achieve a bacteriological standard of< 1000 faecal coliforn1s per gram dry weight (dw) or < 3 Sali11onella per 4 grams dw. The bacteriological standard applies immediately after the treatment process is con, plctcd and also after periods of storage (NRC, 2002). One impo rtant exception to the requirement for biosolids products to be prod uced from defi n ed treatment processes is that the US EPA allows classifica tion based on microbiological batch testin g of products. Biosolids from an unlisted process can be classified as Class A if the product ach ieves the bacteriological limit (i.e. < 1000 faecal coliforms per gram dw or < 3 Salmo11ella per 4 grams dw), < 1 viable helminth ova per 4 grams dw and an enteric virus density of < 1 PFU per 4 grams dw. T he defin ed treatment processes have been assessed on the basis that they can routi nely achi eve these helminth and virus levels. In addition to the above requ irements, meeting the C lass A criteria also requires vec t or attraction red uction (VAR ) measures to be undertaken by either biological degradati on of putresc ible organics, inhibition of biological activity prior to application (e.g. by drying or increasing pH), or through the use of physical barriers (e.g. injection or soil incorporation) (US EPA, 1999; Vesilind and Spinosa, 200 1). Produces chat comply w ith the Class A criteria and the VAR measures are available fo r unrestricted use from a microbiological perspective.

European requirements As noted earlier, the Sludge Directive (86/278/EEC) currently provides the overarching legislative basis for sewage sludge treatment and reuse in Europe. Unfortunately, despite the significance of this document, it provides only qualitative criteria rather than quantitative standards for treatment . Th e definition of treated sludge is "sludge which has undergone biological, chemical or heat treatment, long term storage or any other appropriate process so as significantly to reduce its fermentabilicy and the health hazards resulting from its use" (EC, 1986). Not surprisingly, given the lack of definitive treatment criteria, the current directive is restrictive on acceptable uses of biosolids. In contrast to the approach in the U S of an 'unrestricted' microbiological grade, there are restrictio ns on all


WASTEWATER

Table 1. The key international and national criteria for achieving an 'intensive treatment' grade biosolids product. Defined Treatment Process1

Framework

:§'

C: 0

Q)

.0 ....__

VJ C:

0

:;:;

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CT Q) Q)

E

tE

...,

ro

C: Q)

sro i

Q)

C:

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0.

0

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...,

C:

...,

ro

Q)

0

ro '6

Q)

ro

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~

B VJ

~

0. C:

0

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0

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e

.s::::

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Q)

:0

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M icrobiological criteria

...,

0

VJ

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C:

:;:;

CT

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...,Q)

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~ ...,~ VJ

~

C:

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0

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Q)

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.0

ci

0 ::, "Cl

f-

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(.)

I

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US Part 503 rule (Class A) (US EPA, 1999)

+

+

+

+

+

+

+

European Directive 86/ 278/ EEC

Qualitative statement of treatment to "significantly to reduce its fermentability and the health hazards resulting from its use". Restrictions on end use imposed.

Q)

ro Q)

+

VJ

ro

+

Q)

-~

f- "Cl

+

~ Q) .c -~

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E Q)

0

...J

+

0

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+

+

C:

+

+

+

+

+

+

< 1000 faecal coliforms/ g dw or < 3 Salmonella/ 4 g dw

< 500 E. coli/ g No Salmonella 50g (wet weight)2

+

Qualitative statement of treatment to "significantly to reduce its fermentability and the health hazards resulting from its use ". However, recent validation of microbiological criteria was based on prescribed treatment processes.

Draft Austra lian national guideline (Grade P1) (NWQMS, 2002) NSW gu ideline (Grade A) (NSWEPA, 1997)3

0

+

EC working redraft (Advanced grade) (EC , 2000) UK proposed legislation (Enhanced grade) (DEFRA, 2002)

E

+

< 1000 E. coli/ g dw No Salmonella / 2g dw

< 100 E. coli/ g dw < 1 Salmonella/ 50 g dw

+

+

< 100 E. coli/ g dw < 1000 faecal coliforms/ g dw No Salmonella/ 50g dw

Table notes

1. The specific criteria listed for each treatment process may vary between frameworks. For example, heat drying in the US and in the EC draft directive requires heating to 9096 solids content (1096 moisture) at temperature > BOOC, but the EC also proposes a requirement that the water activity is maintained above 0.9 for the first hour of treatment. 2. The EC Directive redraft lists Sa lmonella units as per gram wet weight, however, the E.coli units are not explicitly describ ed. The majority of j urisdictions express biosolids microbiological limits on a dry weight basis and therefore testing would requ ire a sub-sample to be assessed for dry weight quantification. 3. The NSW guideline describes generic temperature time equations for different biosolids moisture contents, but not prescriptive criteria for individual treatments such as heat drying.

sludge use. T his includes a ten- month post-application withholding period for the use of sludge on land used for fruit and vegetable crops, and a prohibition of the use of sludge on growing fru it and vegetable crops, with the exception of fru it trees. H owever, it is interesting to note that the directive in cludes the potential fo r use of raw sludge by mem ber states and that until recently, this practice was accepted in some jurisdictions. Draft EC directive

Although the current EC directive does not provide detailed criteria on b iosolids treatment, working redrafts of the directive do include quantitative standards. The redraft describes an 'advanced' treatme n t grade that is proposed for unrestricted use. As per the US, th is classification is based on a combination of prescribed treatment processes and microbiological standards. Examples

of treatment processes are described in Table 1. While the EC commissioned a report to examine treatm ent standards (E11aliwtio11 of S/11dge Treatme11ts for Pathoge11 Red11ctio11) (EC, 200 1b), they ultimately proposed a nu mber of process criteria significantly more stringent than suggested in the re p ort. It is also in teresting that composting, although listed in earlier drafts, is not included in the third working draft of the directive. T h is latter point is believed to be due to the development of a E u ropean composti ng directive, rather than a lack of confide nce in the process. The required microbiological standards for confirmation as 'advanced grade' are i) an initial validation of the processes through a 6 log reduction of a test organ.ism such as Sal/l/011ella se1ifie11be1g W775 and ii) no Sal/l/011ella spp. per 50 grams (wet weight) and a 6 log reduction in E. coli to less than 500 CFU per gram (EC, 2000).

Although the basis for these provisions is not described, the approac h being proposed has some ve1y strong similarities with proposed changes in legislative requirem ents within the United Kingdom (UK) (discussed furt her below) . It should be noted that while it is always temp ti ng to accept drafts of regulatory documents as indications of fu ture directions, some caution is needed with th e draft directive, since the redrafting has not yet been through fo1111aJ member state consultation. United Kingdom

The biosolids management framework in the UK is currently of great significance. Recent redrafting of the legislation has been underpinned by a major research initiative commissioned by the UK Water Industry Research Ltd (UKWIR) with the Department fo r E nvironment, Food and R ural Affairs (DE FRA) and the Environment Agency. The research has WATER AUG UST 2003

59


WASTEWATER

involved three compo nents: 1) development o f methods for pathogen analysis and q uanti fica tion, 2) assessment o f pathogen redu ctions through key treatments, and 3) quan titative assessment of the resultant food safety risks. Importantly, the research has not only supported the requirements in an existing code of practice 'The Safe Sludge Matrix', but the code has broad support from organizations such as the British Retail Consortium, which represen t major supermarkets and consumers. In the UK, the key legislatio n is the UK Sludge (Use in Agricult11re) R egulations 1989, and proposed amendments to the legislation involve the fo llowing definition of Enhanced treated sludge: (DEFRA, 2002) : "sludge or septic tank sludge which has undergone a biological, chemical o r heat treatment process, long term storage or any other appropriate process so as sign ificantly to reduce its fermcntabi lity and the health hazards resulting from its use, being a process of such a character that it causes Sa/11u111ella spp. to be absent and ensures a 99 .9999% (6 log) reduction of the indicator pathogen E. coli, with a maximum all owa bl e concentr atio n (MAC) of E. coli of 103 per gram dw" (DEFRA, 2002).

It should be noted that a defin ition of 'Sal111011ella spp. absen t' is not provided. T esting for Sal111011ella is based on 2 grams dw of sludge, and hence it is assumed that the criteria is 'not detectable' Salmonella per 2 grams dw. One potential difference between the US legislation and the proposed UK changes is that there isn't a prescriptive linkage in the legislatio n between listed treatment processes and the microbiological criteri a. However, this linkage appears likely to occur in practice, since the underpinning report, UKW IR (2002), recommended that only thermal treatment processes (for example, thermophilic d igestion, composting, and thermal drying) or autothermic processes (such as lime treatm ent) shou ld be used for uses requiring en hanced treated sludges. Further, the UK water industry has historically followed presctiptive treatment criteria such as sludge pasteurization being defin ed as~ 30 minutes at 70°C or ~ 4 hours at 55°C (or appropriate interm ediate conditions), fo llowed in all cases by primaty mesophilic anaerobic digestion (DoE, 1989). An additi onal difference in the UK approach compared to the U S is that the proposed legislation includes some restrictio ns on use, for example a ten-month w ith holding period before harvesting of 60

WATER AUGUST 2003

food crops co nsumed raw, such as vege tables. H owever, this appears to be drive n by the legislative req uirem ent to adopt the current restrictions w ithin the EC directive, rather than being an important control step identified in the risk assessm ent process. N evertheless the w ithh o lding period has been supported within the 'Safe Sludge M atrix' and therefore app ears likely to be applied, wh ether dri ven from a statu tory or voluntary basis. France

With regards to the range of microbiological standards that are applied, it is useful to note the EC (2001) description of ' hygienised' sludge in France, which is based on: < 8 Salmonella MPN per 10 grams dw, < 3 MPCN enteroviruses per 10 grams dw, < 3 H elminth eggs p er 10 grams dw . T he document is not clear on the acceptable uses for 'hygienised' sludge.

National Australian guideline The draft of the national guideline for biosolids management Guideli11es for Seu1erage Syste111s - Biosolids l\!Janage111ent under the NWQMS makes an important stru ctural distinction from the US and Europ ean approach, effectively dividing th e 'intensive treatment' grade classification into two ca tegories. However, the philosophy of linking the treatm en t process with microbiological criteria remains unchanged. Th e unrestricted grade (grade Pl) includes microbiological criteria of < 1 Salmonella p er 50 grams d w (i .e. undetected) and < 100 E. coli (or thermotolerant coliforms) per gram dw. These mi crobiological standards are linked to treatments that are comparable to the 503 rul e (Table l ) . A sl ig htl y redu ced treatment grade, but still comparable to the requirements in the U S and draft European directive is defined as grade P2. This grade involves some restrictions on enduse, for example it is not permitted for u se in recrea ti onal or r es id e ntial landscaping. The microbiological standards for grade P2 are < 10 Salmonella per 50 grams dw and < 1000 E. coli (or thermotolerant coliforms) per gram dw. A number of the prescribed processes are comparable to the Pl requirements, i. e. the composting temperature-time profile is identi cal, meaning th e main practical application is likely to be for producers targeting P1 but who occasionally do not make the relatively stringent P l microbiological criteria. However, there are also described P2 processes that are no t

included with in the P l processes.

trea tmen t

New South Wales The most widely recognised gu idelines in Aus trali a are the E1/.lliro111nental Gu ideli11es: Use and Disposal of Biosolids Products (NSW EPA, 1997) . They specify similar treatment processes to the draft national guideline (albeit the presentation is altered). The microbiological standards for the unrestricted grade product are also comparable, listing < 100 E. coli per gram dw, < 1,000 faecal coliforms per gram dw and no detectable Sal111011ella per 50 grams dw.

'Class B' requirements An area of relative consistency in international regulation of biosolids is in the definition of the 'base' grade of biosolids treatment: • The US part 503 describes a 'Class B' product w hich is derived fro m Processes to Sign ifican tly R ed u ce Patho ge ns (PSRPs), such as m esophili c anaerobic digestio n for 15 days at 35°C, coupled to a microbiological limit o f < 2x106 faecal coliforms per gram dw; • While the current EC sludge directive only includes a qualitative description of sludge treatment, the current redraft is more closely align ed with the US approach. The redraft describes a range of 'conventi onal' treatment processes, which include mesophil.ic anaerobic digestion for 15 days at 35°C. However, this is coupled to microbiological crite ria of a 2 log reduction in E. coli. While the US and EC align on processes such as mesophilic ana erobic digestion, there are some differences in listed processes; • The prop osed UK legislative changes include a definition of 'conve ntionally treated sludge' w hich is based on a qualitative description of treatment, coupled to a 99% (2 log) reduction of the indicator organism E. coli, w ith a m aximum allowable concentration (M AC) of E. coli of 10 5 per gram dw; and • T he draft Australian national gu ideline includes comparable treatment processes and microbial criteria to the US 503 rule, however the Australian approach is based on the m onitorin g of E . coli rather than faecal coliforms, as in the US . It is interesting to note that the N SW guideline also lists the treatment processes, but relies on more qualitative process descriptors cou pled to stabili zation cr ite r ia . Microbiological standards are not imposed. Although the juri sdictions are in practice roughly aligned on the generics of treatment class ifi ca tion, the end use


WASTEWATER

Table 2. Key management controls for land application of restricted grade biosolids in different j urisdictions. Framework

Livestock grazing

Food crops

Landscaping

US Part 503 rule (Class A) (US EPA, 1999)

30 day withhold.

Where month Where month month

For areas with high potential for public access - 1 year access restrictions. For areas with low potential for public access - 30 days.

Third worki ng draft of EC directive (Conventionally treated) (EC, 200 0 )

6 week with hold post deep inject ion.

Not permitted for food crops that contact the soil, but lists 1 2 month withhold for fru it and veget ables and 30 month with hold where t he produce is consumed raw. Permitted for crops that don 't contact the soil, with 10 month public access withhold.

UK proposed legislation (Conventionally treated) (DEFRA, 2002).

Three weeks withhold, but Code of Practice more stringent.

Vegetable crops, 12 month withhold . Salad crops, 30 month withhold.

Draft Australian national gu ideline (P3) (NWQMS, 200 2)

Incorporation and suitable withholdi ng pe riod .

Permitted with incorporation and suitable withholding period for crops consumed cooked or processed. Not permitted for salad plants and root crops.

Not pe rmitted for institut iona l landscaping, incorporation for land rehabilitation.

NSW guideline (Grade BJ (NSW EPA, 1997)

No grazing within 30 days of applicat ion. No pig or poultry grazing. Lactat ing and new-born animals - 90 day withhold.

Where harvested product may touch soil - 18 month withhold. Where harvested parts be low ground - 5 year withhold. Where harvest parts don 't contact biosolids 30 day withhold.

Areas with high potential for public access - 1 year access restrictions . For areas with low potential for public access - 30 days.

contro ls are a source o f signifi can t di fferences.

Future directions and key activity areas T here is ge ne ral consistency in the internati onal approac h es w ith regard to the man agement of biosoli ds m icrobiological qua lity . T herefo re, there appears to be li mited po te ntial fo r significant c h an ges in th e c urre n tl y accep ted treatme nt processes or in o rga nisms that are currently used fo r process mo nitoring. T he key areas of futur e activity would appear to be in th e areas o f: â&#x20AC;˘ quantitative risk assessme nts to de mo nstrate th e safety o f land appl ication , particularly for biosolids w here restri ctions are applied to their use (fo r exam ple, a produc t from mesophili c digestio n); â&#x20AC;˘ refi nement o f criteria for th e validation and assessm ent of e merging tec hno logies that are no t cu rrently presc ribed in legislative fra m eworks; and â&#x20AC;˘ the m ic robiolo gical c riteria that apply fo r process monitoring o f an unrestri cted grade p roduct, fo r example < 1 Sa/111011ella p er 5 grams dw ve rsus < 1 Sa/111011ella per 50 grams dw. Quantitative risk assessment processes

As noted earl ier in this pap er, existing microbi ological controls fo r biosolids have evolved from a reliance o n historical prac t ic e, co upl e d w it h av ail a ble tech n ologies, analytica l m ethods an d professio nal judgement, to develop what

harvested product may touch soil - 14 withhold. harvested product below soil - 20 withhold for surface applicat ion, 38 withhold for incorporation.

has bee n co n sid e red a co nse rvative fram ework. It is on ly rece ntl y that fo rmal ised quantitative risk assessm en t tools have begun to be appli ed to b iosolids m an age m e nt, su c h as t he techn iqu es used to support the proposed UK legislative changes. H oweve r, it appears that there wilJ need to be an increased emp hasis on suc h tec hniques so as to demonstrate th e safety of biosoJids land appli catio n to th e co mmunity . In so me parts of the US, th ere ha ve been sign ifi cant co mmunity con cerns rega rding C lass B la n d ap p lica ti o n p rograms. While aesthetic issues appear to have dri ve n the con cerns, publi c health concerns have been pro mine nt in the com m unity. T his is despite the p ro tectiveness o f current biosolids controls being supported by rece nt reviews, with the NRC (2002) concluding that b iosolids land applicatio n has not bee n asso ciated with scienti fically docum ented outbreaks or excess illnesses, and the EC (2000) concl uding that in the limited cases w he re an inc ide nt ha s bee n do c u m e n te d , practices did not comply with the relevant guidelines. Th e p ro tectiveness of th e current controls is also supported by a key study (D orn et al.1 1985; Ottole nghi and H am parian , 1987) w here the health of fa rm families and cattle o n fa rms using biosolids were compared with control farm groups over one year periods. T he researc hers repo rted no significant differe n ces in sy m pro m s o r serol ogic al param eters be tween the groups.

Not permitted for public access areas , e.g. parks. For land reclamat ion , 10 month wit hhold.

O ne specific area o f control that may be subj ec t to future atte ntio n with updated risk assessmen t app roac hes is the current U S 30-day withholding period for cattl e grazing on C lass B am e nded pastures. Th e US EPA is co nsidering th e need for reviewing the standard based on j oint research on manure management and the developm e nt o f a m icrobi al ri sk assessme n t m odel (NRC, 2002). Verification of emerging technologies

A key challe nge facin g Australian and in tern ati o nal regulators is th e evaluation of novel technologies, pa rticularly fo r ' unrestricted ' grade products. The US EPA has a relative ly transpare nt pro cess, with novel tech nologies able to produ ce a C lass A product through two contrasting options. Th e fi rst optio n is to obtain an equi valency as a P FRP , through dem onstrating the process ca n achi eve the bacteri ological standards described earlier and also reliably ac hieve at lease a 3 log re moval of viruses and a 2 log reductio n in helm inth ova. The al ternative option is to u ndertake batch testing of th e final produ ct and show that the bacteriological standards have been ac hie ved and the product has less than < 1 viabl e helminch o va pe r 4 grams dw, and an ente ric virus de nsity o f< l P FU per 4 grams dw. Whil e t h e rela ti ve resista n ce o f h elmi nth ova m eans these approaches have a logical basis, th ere are some pra ctica l d iffi culti es in implem e nti ng within Australia, as co mpared to many parts o f the world, the majori ty of WATER AUGUST 2 0 03

61


WASTEWATER

Australian population centres have low incidences of key helminth infections. Gibbs and Ho (1993) cited a reported incidence rate of Ascaris and Trichuris of 0.001 and 0.01 percent, respectively, in the Perth population in the early 1990s. T his was predominantly due to travellers and recent immigrants, rather than the resident population. In contrast, Barbier et al (1990) examined sludge from a French STP and estimated a helminth infection rate in the local population of 1. 5 to 2.7 percent, a figure considered to be similar to the national average. T he low incidence rate in Australia means chat it is difficult to demonstrate a 2 log reduction as per the US approach (without seeding studies) and further, an absence of helminth ova in a batch product test may provide no assurance that other pathogenic organisms have been removed (i.e. an absence of helminth may be due co no helminths in the raw sludge rather than removal by the treatment process) . Therefore, in Australia, greater emphasis may need to be on batch testing for viruses, bacteria and ocher organisms such as protozoa. The emerging approach within Europe for validating new technologies appears to be focused on demonstrating 6 log reductions of Salmonella seriftenberg or E. coli. However, it is not clear whether this is intended to apply o nly to already prescribed treatments, or whether it is an approach that can be automatically applied to new technologies. The former appears the most likely scenario, since the UK proposed legislative changes were underpinned by the demonstration that specified technologies achieved high log reductions against a wide range of key pathogen organisms, for example Campylobacter, Giardia and enteric viruses. If this is indeed the approach , it presents the challenge chat emerging technologies will have no fo rmal criteria against which to be assessed. It is interesting to note that for the previous treatment requirements in the UK, process efficiency is believed to have been based on evidence of90% reduction in Salmonella and Taenia saginata egg infectivity (although these biosolids had restricted uses) (UKWIR, 2002). In the proposed national Australian guideline, some specific direction is provided, with emerging technologies required to demonstrate 100% egg inactivation using a Taenia or Ascarid parasite egg- seeding assay and demonstrate < 1 enteric virus per 100 grams of final product. T he key challenge will be in ensuring the testing laborato ries are equipped to undertake these tests to the relevant standards. It therefore appears to be critical that some provision for batch

62

WATER AUG UST 2003

testing of products is included in state guidance. T he difficulty, as highlighted with the low incidence rates for helminths, will be in selecting indicator organisms that provide assurance of broad pathogen removal. Process monitoring of an 'unrestricted ' grade product - Salmonella

As noted earlier, there are some significant differences in the international approaches to how Salmonella testing is used for assessing an 'unrestricted' grade biosolids product. T he US 503 rule includes an option of Salmonella testing, however, the testing is not recommended as a treatment verification tool (NRC, 2002). The draft EC requirements require treatment verification through a demonstrated 6 log reduction in Salmonella senftenberg W775, while a demonstration of non-detectable Salmonella is required in the draft UK (not detectable in 2 grams dw) and Australian (not detectable in 50 grams dw) approaches. A detailed examination of the basis for the Salmonella provisions is beyond the scope of this paper, other than to note the limits reflect con cerns regarding the importance of Salmonella as a pathogen (Carrington et al., 1991), its potential fo r regrowth and the difficulties some treatment processes have had in ac hieving adequate removals (Yanko, 1988; H ay, 1996; Gibbs et al., 1997) . While these reasons are clear, the justification for a highly sttingent Salmonella limit such as no detectable organisms per 50 grams dw, compared to the criteria proposed in the EC, is less clear.

Conclusions T here is a generi c level of consistency in the pathogen management approaches taken in the U S, E urop ean Commission (proposed approach) and the draft national Australian guideline, particularly with regard to the types of treatment processes required and the organisms that are used for process monitoring. There are also some important similarities in the end-use restrictions that apply to the specified products . From this perspective, there appear to be relatively stable framewo rks fo r the future management of biosolids application co land. Although the current management controls are believed to be appropriately conservative, there are some issues around the community acceptance of 'Class B' application programs. Therefore, there will need to be an increased focus on quanticati ve risk assessment approac hes to demonstrate the safety of the practice. There are co nsistencies and some issues around the regulatory limits established for

p rocess monitoring of defined treatments and the approaches used to ve1ify emerging technologies. It appears that future regulatory activities w ill need to focus on these latter areas.

The Authors Dr Hamish Reid (hamish.reid@ epa.vic.gov.au) is employed by the Victorian EPA as W ater Industry Program Leader, with an involvement in programs including biosolids and reclaimed water ma n agement. Amelia Savage is employed by the Victorian Department of H uman Servi ces and is involved in assessing the public health impacts of biosolids and reclaimed water management policy. References Barbier D, Perrine D,.Duhamel C, Doublet R, and Georges P (1990). Parasitic hazard with sewage sludge applied to land. Appl. E11viro11. Microbial. 56(5):1420-1422. Carrington E G, Pike EB, Auty D. and Morris R (1991) Destrnction of Faecal bacteria, enteroviruses and ova of parasites in wastewater sludge by aerobic thermophilic and anaerobic mesophilic digestion. Wat. Sci. Tech. 24(2): 377- 380. DEFRA (2002) Consultation paper - Proposals to amend the statuto,y controls for the agiicultu ral use of sludge. De partment for Environment, Food and Rural Affairs, Welsh Assembly Government. October, 2002. DEP (2002) West Australian guidelines for direct land application of biosolids and biosolids products. Department of Environmental Protection, Water and Rivers Commission, Department of Health. February 2002. DoE (1989) Code of Practice for Agriculture Use of Sewage Sludge. D epartment of Environment, United Kingdom. Dorn C R, Reddy C S, Lamphere D N, . Gaeuman G V and Lanese R (1985) Municipal sewage sludge application on Ohio farms: health effects. Ellviro11 . Res. 38(2): 332-359. DPIWE (1999) Tasmanian biosolids reuse guidelines. Department of Primary Industries, Water and Environment. EC (2000) Working Document on Sludge. 3rd Draft. Brussels, 27 April 2000. EC, (2001) Evaluation of Sludge T reatments for pathogen reduction. Report Number CO 5026/ 1. European Commission, DirectorateGeneral Environment. EPA Victoria (2002) Draft Guidelines for Environmental Management: Sustainable reuse of biosolids - land application. November 2002. G ibbs RA and GE Ho(l 993) Health risks from pathogens in uncreated ¡wastewater sludge implications for Australian Sludge Management Guidelines. Water 20 . February: 17-22. Gibbs R A, H u CJ, Ho G E and Unkovich I (1997) Regrowth of faecal colifonns and salmonella in stored biosolids and soil amended with biosolids. Water Sci Tech 35(11 / 12) 269275.

Continued over page


AWA CRUCIAL ROLE FOR MEMBERS AW A relies almost entirely on the active support and involvemenc of its members to achieve what it does. As for any membership organisation, ours stands or falls o n the fac t that members are willing to pay to belong, then take part in the association's activities. Membership with AWA is fantastic value, particularly when compared to subscriptions for similar o rganisations. AWA continues to present the most up to date, balanced and considered perspective on a broad range of water related issues. To maintain and improve this industry leadership role we rely upon continued member involvement - if you know other people in the water industry who are not members, why not encourage them to join today!

Categories and Costs Membership of AWA is open to students, individuals, retirees and organisations. Any queries can be directed ro o ur national, local-call number 1300 361 426, or visit our web sire ar http:// www.awa.asn.au.

Collaboration Apart fro m its own membership, AW A's direction is to collaborate with sister associations as far as possible, to achieve common goals and co minimise overlaps. Internationally that is being achieved with !WA, the International Water Association. T he 2003 Australian Water Directory which includes corporate members of the Australian National Committee on Irrigation and Drainage (ANC ID) and the Water Services Association (Vl,/SAA) is now available online and in prim, making it the most comprehensive and up to date wate r industry reference.

CONTACT US For more in fonn atio n or contributions to this membership page, contact the AW A National

MEMBERSHIP

Office on 1300 361 426 o r membership@awa.asn.au

NEW CORPORATE MEMBERS New M embers Since the last issue of Water the following new members have joined and we welcome them all into the AW A family: N SW Corporate Platinum Henry Walker Eltin Group Ltd/ Simon Engineering PO Box 364 North R.yde NSW 1670 T el: 02-9887-6320 Utility Gold State Water PO Box 717 Dubbo NSW 2830 T el: 02-6841-751 8 Corporate Silver Barclay Mowlem Construction Limited Locked Bag 1008 Pymblc NSW 2073 Tel: 02-9855-1600 Utility Bronz e Young Shire Council Locked Bag 5 Young NSW 259-1 Tel: 02- 6382-5088 QLD Corporate Gold Golder Associates Pty Ltd PO Box 173-1 Milton QLD -106-1 Tel: 07-372 1-5-100 Utili ty Bronze Port of T ownsville PO Box I03 I T ownsville QLD 4080 Tel: 07- 4781-16 19 SA Corporate Bronze Wonder Treat Australia Pty Ltd Etas Building Ground Floor I Anzac Highway, Keswick SA 5035 Tel: 08-8404-50 15

Abigroup Asset Services PO Box 901 Sunshine VIC 3020 T el: 03-9361-7222 VIC Corporate Gold Leeder Consulting Unit 5, 18 R edland D rive, Mitcham VIC 3132 T e l: 03-9874- 1988 Corporate Silver Dept Sustainability & Environment, Catchment & Water PO Box 500 East Melbourne VIC 3002 Tel: 03-9412-4020 WA Corporate Gold Leigh ton Contractors Pty Ltd PO Box 1070 West Perth WA 6872 T el: 08-9324- 1166 Corporate B ronze Western Radiation Services PO Box -11 8 C loverdale WA 6985 Tel: 08-9470-3000 Environmental Health D irectorate D e partmen t of Health (\VA) Grace Vonghan House 227 Stubbs T errace Shen ton Park WA 6008 Tel: 08-9388-4953

NEW INDIVIDUAL MEMBERS Overseas M. Paschke, R. Wagner ACT I. Bergman

NSW R . Hatley, N. Austin, A. Bradshaw, K. Byrnes, B. Edgerton, D. Gaskell, F. Langley, A. Murdoch, A. Owen, S. Pandey, R . Prsa, R. Quinn , H . Terry, D. Tho mpson, L. Wakefi eld, R.. Young, M. J avdan- Mowlaei, A. Panikkar NT

Con ti1wed from previous page Hay J C (1996) Pathogen destruction and biosolids composting. Biocyde]une: 67 - 76. NRC (2002) Biosolids applied to la nd: advancing standards and practices. National Research Council. Prepublication copy. National Academy Press. Washington D C. NSW EPA (1997) Environmental Guidelines: Use and disposal ofbiosolids products. New South Wales E nvironm ent Protecti on Authority. NWQMS (2002) Dreft C 11ideli1ws for Sewerage Ma11age111e11t - Biosolids Ma11ageme111 May 2002 public consultation under the National Water Quality Management Strategy. Ottolenghi AC and H amparian V V (1987) Multiyear study of sludge application to farmland: prevalence of bacterial enteric pathogens and antibody status of farm families. Applied E11viro11111e111a/ Microbiology 53 (5): 1118- 1124. SA EPA (1996) South Ausrralian biosolids guidelines for the safe handling. reuse or disposal ofbiosolids. South Australian Environment P rotection Authority, D epartment of Environment and Natural R esources.

N . McCarthy, J. Pudncy, J. Sage, M. Wiltshire Yanko W A, Walker A S, Jackson J L, Libao L L and Garcia A L (1995) Enumerating Salmonella in biosolids for compliance with pathogen regulations. Water Enviro11111e11t Research 67(3): 36-1- 70. UKWIR (2002) Pathogens in biosolids - the fate of pathogens in sewage treatment. Report R ef. No. 02/SL/06/6. UK Water Industry Research. US EPA, (1999) Control of pathogens and vecto r attraction in sewage sludge. Environmental R egulations and Technology Victoria n EPA (2 002) Guid e line for Environmental Management: Biosolids land application (October Draft). Victorian Environm ent Protection Authority. Vesilind P A. and Spinosa L. (2001) Production and regulations. I,, Sludge into Biosolids: Processing, Disposal and Utilization. Chapter 1 (Eds Spinosa L. and Vesilind P A.) IWA Publishing, London pp 3-18. WSAA (2001) WSAAfacts -T he Australian Urban Water Industry. Water Services Association of Australia.

QLD A. Boasc, A. Bond, A. Bruto n, R . Caswell, R .

Fearon, D. Hains, C. Lemckert, T. Morris, P. M ountney, L. Opray, G. Peril, P. Sherman SA A. Howes, A. Bowman, N. Dastoor, S. D uffett, R. Fabris, J. Gregson, K. Kang, S. Kotz, W. M oore, E. Munro, N. Taylor, K. Ward TAS D. Dettrick VIC A. Gartner, B. M cilrath, C. Arabarzoudis, J. Bartley, R. Bruerton, T. Dalgleish, B. D ynes, D. Friend, F. Gauci, S. Hawthorne, M. Hill, A. Jayaratne, N . Langridge, R.. Marguccio, J. M cCallum, R. Millen, R . Nixey, W. Osborne, C. Piccinin, I. Posenjak, N . Ri ntoul, A. Savage, A. Slocombe, P. Solomon, J. Stokes, A. Szann, M. T omkins, S. Torre, S. T ucker, M. Veness, J. W ebb, T . Wood, C . Wootton, N . Douglas, D. M cDonald, H . Alford, R . Beeck, B. Agarwalla, J. Law, D. Murphy, M. Russo, A. W yber

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MEETINGS For iiifor111atio11 about the e11e11ts listed, co11tact A WA Natio11al Office. Tel {02) 941 3- 1288, Fax: (02) 94 13- 1047, Email: i1ifo@a111a.asn.a11 or visit 011r website: w111111.a111a.as11.a11 AUSTRALIA 2003 14 August, Melbourne, VIC - AWA CORPORATE MEMBERS Executive Briefing - Smart Water. 1.30-6.00pm.Grand Ballroom, Sofitel Hotel. Contact: Clare Porter, T el 02 9-11 3, 1288 Fax: 02 9413 10-17, Email: events@awa.asn.au 14 August, Melbourne, VIC VIC A WA Branch ACM and Dinner. Grand Ballroom, Sofitcl Hotel. C ontact: Joe Owzinsky, VIC Branch, Tel 03 9509 2748 , Fax: 03 9509 8243 Email: awwa@i.net.au 19 August, Sydney, NSW C ommunity Consultation in the Australian Water Industry. J oint C onference IAP2/ AWA. Contact: C lare Porter, Tel 02 941 3 1288, Fax: 02 941 3 1047. Email: cporter@awa.asn.au. 28-29 August, Sydney NSW 2003 Heads of Water (HOW 2003). ANA Hotel Sydney. Contact: Rob Craig. T el: 02 9495 9914, Fax: 02 941 3 1047. Email: rcraig@awa .asn.au 1-3 September, Brisbane, QLD 2nd National C onference on W ater R ecycling in Australia. C ontact: Kathy Bourbon, AWA Q LD Branch on 07 3397 564-1, Fax: 07 3397 5283 or email: awaq@powerup.com.au 3-4 September, Brisbane QLD Workshop on Quantifying the Health Risks from W ater R.ecycl ing Schem es. Contact: Ted Gardner by email ted.gardner@nrm.qld.gov.au 2-5 September. Brisbane QLD Ri versymposium 2003 - Urban Rivers, Balancing the expectations. Sixth International R iver Management Symposium. Contact: Mr Stephen Nelson. T el: + 61 (0) 7 3846-7444. Fax: +61 (0) 7 3846-7660. Email: symposium@riverfestival.com.au . W ebsite: www.riverfestival.com.au/symposium. 16-17 September, Penrith NSW NSW Operators Conference 2003. Penrith Panthers. Contact: R.ob Craig. T el: 02 9495 991-1, Fax: 02 941 3 10-17. Email: rcraig@awa.asn.au 30 Sept to 2 Oct. Armidale, NSW O n-Site '03 - Urban Rivers, Balancing the expectations. Sixth Internatio nal l'tiver Management Symposium. C ontact M r Stephen N elson, T el: 07 3846 7444, Fax: 07 3846 7660. Email: symposium@ riverfestival.com.au . Website: www .1iverfescival.c0m .au/ symposiu111 21-23 October. Wagga Wagga, NSW Pipes W agga Wagga 2003: Back to Basics. Venue: CSU Wagga Wagga. C ontact: Penny Lamont. Tel 02 6924 63 11 Fax: 02 6924 6411. Email: pipes.wagga@bigpond.com. Website: www.pipeswagga .com.au 27 October. Newcastle NSW AW A NSW R.egional C onference 2003. Contact: R ob Craig. Tel: 02 9495 991 4, Fax: 02 9-11 3 1047. Email: rcraig@awa.asn.au 10-13 November, W ollongong NSW The Institution of Engineers, Australia. 28th International Hydrology and Water Resources Symposium - Abo ut Water. Novotel N orthbeach, Wollongong. C ontact: James Ball . Email: HWRS2003@webbmckeown.com .au. Website: www.hwrs2003.org.au 14- 16 November, Caloundra, QLD AW A Queensland Conference. C ontact: Kathy Bourbon, AW A Q LD Branch on 07 3397 56-1-1, Fax: 07 3397 5283 or email: awaq@po werup.com.au 1-5 December, Warrnambool, VIC Australian Society for Linrnology - 42nd Annual ASL C ongress. W armambool Campus of D eakin University. Contact Belinda R obson via email : brobson@deakin .edu.au

OVERSEAS 2003 18-20 August, City of Kalmar, Sweden Transboundary Waters - Issues and Options for the Future. Contact: Elisabet Idermark- Kalmar University. T el: +46 480 497 01 4. Email: clisabet.idermark@hik.se 20- 23 August, Tampere, Finland D ry T oilet 2003. The fi rst international Dry T oile t conference. University of T ampere, Finland. Organised by the Global Sanitet C lub of Finland & the Ecological Informatio n Association. Contact: TAVI

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WATER AUGUST 200 3

Congress Bureau . Fax: + 358 3 233 04-14 Email secretary@drytoilct.org W eb: www.drytoilet.org 25-29 August, Mexico City, Mexico 6th IRCSA Confe rence (International R ainwater Catchment Systems Assoc). Contact: Dr Manuel Anaya- Garduno. I RENA T. T el. + 52 (595) 95 I 03 23 Fax: +52 (595) 952 02 38. Email: ircsa@colpos.mx/irsca/ 1-4 September, Prague, Czech Republic 9th IW A Specialised Confere nce: Design, Operation and Economics of Large Wastewater Treatment Plants. !CARIS Conference Management. T el: + 420 284 828 48 I Fax: + 420 266 3 12 I 13. Email: icaris@icaris.cz. Website: www.ace-cr.cz 13-14 September, Mumbai, India 8th IWWA Internatio nal Co nference, W ater Co nservation & R.euse of W astewater. Contact I WWA Email: iwwa@rediffi11ail.co111, T el: +9 1 (22) 2 6 14 0926 Fax: + 9 1 (22) 2 6 18 61"13. W eb: www.iwwainternatio nal.com 11-15 October, Los Angeles, California, USA WEFTEC 2003 - The Water Quality Event. 76ch Annual Technical Exhibition and Conference. Los Angeles Conventio n Centre. Contact T el: 1800 666 0206 or + I 703 684 2452 (globally) . Fax: 1703 684 2471 Email: confinfo@wef. org. W ebsite: www.weftec.o rg 13-18 October, Cebu City, Philippines 13th IWA-ASPAC - W ater Philippines 2003 - M eeting the present challenges with the vision for global concerns. Contact Water Philippines organizing Committee. Tel: +63 2 920 7 1-15. Fax: +60 2 920 71-13 Email: pwwa@info.com.ph. Webiste: www.pwwa-iwaaspac.org.ph

ADVERTISERS INDEX Haestad Methods Wallace & Tiernan Merck VEGA Australi a International Protective Coatings Mox Products Wallingford Software JWP Aquatec Fluid System s Australian Pollution Engineering Q uitz Event Manageme n t Fabtech S.A. Centrilift Environmental Tech nologies Earth Tech AGAL T hompsons Kelly & Lewis Pro-Bae Industries P si-Delta Ecotox Services Australasia Veolia Water James C umming & Sons Water Corporation Flexible Pipe C leaning Tools G rundfos River Sands WestWater Enterprises Clean Water Diving U nit Process Consulting Pryde Measure1nent Iplex Pipelines Hepworth Australia U ltraviolet Technolo gy of Australasia Mox Products

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Water Journal August 2003  

Water Journal August 2003