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Volume 32 No 3 May 2005 Journal of the Australian Water Assoc iation
Editorial Board F R Bishop, Chairman B N Anderson, G Finke, G Finlayson, GA Holder, B Labza, M Muntisov, F Roddick, G Ryan, S Gray, A Gibson, P Mosse, C Diaper
OPINION 2
17
Water is a refereed journal. This symbol indicates that a paper has been refereed.
Submissions Instructions for authors can be fo und on page 2 of this journal. Submissions accepted at: www.awa.asn.au/publications/
Managing Editor Peter Stirling
Technical Editor E A (Bob) Swinton 23 Blaxland Road, Wentworth Falls, NSW 2782 Tel +6 12 4757 1565 Email: bswinton@bigpond.net.au
News Editor Clare Porter Communications Manager Tel +612 9413 1288 Fax: +6 1 29413 1047 Email: cporcer@awa.asn.au
Final Farewell; Water Must Become an Equal Opportunity Industry; Future Urban Water Supplies, T Anderso n
ASSOCIATION ACTIVITIES 6
AWA Sexual Harassment Policy; Awards; Welcome to some new faces at AWA!
INTERNATIONAL 14 WaterAid Australia Update; IWA Australia PROFESSIONAL DEVELOPMENT 15 Details of courses, classes and other upcoming water events CROSSCURRENT 16 Industry news CONFERENCE REPORTS 26 RMIT-UCLA Conference on Water Recycling; Singapore TECHNOtour
WATER SUPPLY 30
Water Production
WATER TREATMENT ALLIANCE A self-help continuous improvement program P Mosse
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Graphic design: Mitzi Mann
INCIDENT MANAGEMENT IN PRACTICE A small town copes with a major spill B Ashworth
MEMBRANE TECHNOLOGY 36
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DESALINATION OF WASTEWATER EFFLUENT FOR REUSE
Water (ISSN 0310 - 0367)
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AWA
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President Rod Lehmann
Chief Executive Officer
AUSTRALIAN WATER ASSOCIATION
G All inson , A W att, D Gervasi, B M itchell
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TRAINING FOR WETLANDS IN NSW AND VICTORIA Professional design courses need follow-up at grass-roots level
Chris Davis Australian Water Association (AWA) assumes no responsibility for opinions or statements of facts expressed by contributors or advertisers. Editorials do not necessarily represent official AWA policy. Advertisements are included as an information service tO readers and are reviewed before publication t0 ensure relevance tO the water environment and objectives of A\Y/A. All material in Water is copyright and should not be reproduced wholly or in part without written permission.
Water is sent t0 all A\Y/A members eight times a year. Jc is also available via subscription.
RENOVATING A CONSTRUCTED WETLAND FOR INDUSTRIAL WASTEWATER TREATMENT
Design was good, but poor establishment caused failure
56
[iii RISK MANAGEMENT AND DUE DILIGENCE IN THE WATER INDUSTRY The legal responsibilities for water quality A D avison , D Deere
LEGAL AND COMMERCIAL ISSUES IN PRIVATE SECTOR DESALINATION PROJECTS Reviewing the ris~s in a public/private venture J Ricketts, K Jagger, M C ave
WATER BUSINESS NEW PRODUCTS AND BUSINESS INFORMATION SPECIAL FEATURES: INSTRUMENTATION AND ODOUR MANAGEMENT OUR COVER: Huge seawater desalination projects are scheduledfor WA and SA and are being investigated for some ofthe other states, but there are already numbers ofsmall plants operating all over the continent, including this 1.3 ML/d RO plant at Yulara, which has recently replaced the 17 year-old EDR plant. But there is more to membrane technology than desalination, as summarised in the feature which starts on page 36. Photo courtesy ofArup Water which managed the Yulara project on behalf ofNT Power and Water.
from the president
FINAL FAREWELL There is always a significant debate on how AWA sho uld involve itself in policy and media liaison. W e have tried a nu mber of ap proaches, and whilst there have been some successes we have still not achieved th e ou tcomes that we wan t. AWA does face a dilem ma in regard to form u lati ng policy how do we seek ou t the diverse views of members and get consensus and how do we p resent the diverse views of members to members, the p ublic and th e med ia in an impartial and balanced way. W e have travelled down the path of preparing position papers bu t these took a lo ng time to p repare and they lost the impact by time they reached the table. W e have tried to up the ante with the med ia in the past with sp asmod ic success but it is pleasing to note that over the last two years we have been much more successful with med ia coverage through the help of our media co nsultants Bay Streer M ed iaworks. C h ris Davis, our official spokesperso n, has ach ieved good exposure o n the rad io and in th e press as a resul t. Media exp osure is a two edged
initiatives with the state politicians and senio r bureaucrats. This will require a further investment in time and money if we are to be su ccessful. T h ese issues will be the subject of debate over the next few mon ths when the Board grapples with policy strategy and Bran ch programs and budgets .
there is a strong belief by many memb ers that we need to have a stronger presence with sen io r bureaucrats and poli ticians. Once again there have been mixed results in this area and performance has varied from state to state and issue to issue. Whilst Chris Davis h as achieved so me successes at Federal level, when advice is sought, we are often the o nes not so ught out. The National Pol icy C ommittee resolved at the last meeting that we n eed greater resource inpu ts if we are ro achieve some of the objectives of the Committee. T he Committee has also agreed
A WA needs to invest more in the policy and communications area if it is to become a genuine advocate of water policy. sword , however, and there may be rimes when a statement made in good fa ith has been misunderstood or slanted in a direction no t anticipated at the rime the statement was made, particularly in the case of live in terviews. T his n eed s to be accepted by members if we are to be part of the med ia scene. W hilst the old adage o f "there is n o such thing as bad p ublicity" might ap ply in theory, I can assu re you it do es not carry m uch weight when there is an angry mem ber on th e lin e. Apart fro m position papers, media releases and interviews
2 MAY 200s
water
that we need to be expand ing our presence over many fro n ts rather than with the media alon e. At a recent Branch M eeting a co mment was mad e that AW A was becoming a second t ier organisatio n because of the lack of im pact in the policy area. Whilst the statemen t may have been m ade euphemistically it is worth dwelling on. AWA need s to invest more in the policy and commu nicatio ns area if it is to become a genu ine advo cate of water policy. Recently some Branches have indicated an in terest in furth ering their own
Policy was o ne of the main issues that I wanted to address at the commencement of m y term. It was a h ot topic then and is still a hot top ic now, but this leads me to one of the mai n poin ts that I wanted to cover, that this wi ll be my last report. A new president will be elected at the next Board meeting at the Ozwarer Convention in Brisbane in May. I wish the new President well and I am sure that they wi ll get th e same support that I have been given. O ur team has ach ieved a lot over the last two years b ur in retrospect may nor have achieved all th e things that I wanted ro achieve at the ou tset. Nevertheless we have addressed some more pressing issues in relation to governance and established new financi al and management structures for the Associatio n. T h is will provid e a sound basis for fu ture growth.
water FUTURE MAJOR FEATURES JUNE - Ozwater Conference Report
AUGUST - Assets, Governance & Eco nomics, ASR , Pumping & Pipelines
SEPTEMBER - Fres h Wa ter Ecology , Environm e nta l Flo ws, International Water Supplies NOVEMBER GIS , Advanced Water Treatment DECEMBER - Liquid Waste Trea tment, Project Delivery, Activated Sludge Dynam ics , e-Water CRC
My thanks to the Board and Executive for their support and good humour over the last two years. My thanks also to AWAs officers, particularly Chris Davis, Ian Jarman and Susan W ilkins.
Rod Lehmann
water
Contributions Wanted
Water journal welcomes the submission of papers equivalent 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 journal. Topical stories of up to 2,000 words may also be accepted. All submissions of papers intended fo r the main body of the journal should be emailed to the Technical Editor, bswinton@bigpond.net.au. Shorter news items should be emailed to news@awa.asn.au. A submitted paper will be tabled at a monthly Journal Committee meeting where, if appropriate, it will be assigned to referees. Their comments will be passed back to the principal author. If accepted and after any comments have been dealt with, the final paper can be emailed with the text in MS Word but with high resolution graphics (300 dpi tiff, jpg or eps fi les - Zip disks or CD-ROMs can be accepted) as separate fi les, or hard copy photos and graphics suitable for scanning by the publisher can be mailed to 23 Blaxland Rd, Wentworth Falls, NSW 2782. Authors should be mindfu l that Water journal is published in a 3 column 'magazine' format rather than the full-page fo rmat of Word documents. Graphics should be sec up so rhar they will still be clearly legible when reduced co rwo-column size (about 12cm wide). Tables and figures need to be numbered with rhe appropriate reference in rhe text e.g. see Figure 1, not just placed in the text wirh a (see below) reference as rhey may end up anywhere on rhe page when typeset.
conferences were prepared co drink ic directly, and 16% prepared to drink ic indirectly. Although che research is supportive, at chis stage, only a small amoun t of water is accually pumped back into the reservoirs as planned indirect potabl e reuse. The amount is equal to less than I% of total daily wacer co nsumption, al though PUB hopes to increase chis co 2.5% by 201 I. More co mmonly, N EWater is of such a high quality chat its use is favoured fo r the processes involved with wafer fabrication plants. Considering chat 7% of co ral water consum ptio n is directly related co che 12 wafe r fa b plants in Singapore, the use of NEWacer in manufaccuring processes releases a large amount of potab le water for other purposes. After a fabulous lunch, with thanks to PUB, and a meeting with che PUB Chief Executive, Mr Khoo and his Directors, delegates had the opportunity of visiting one of the wa fe r fo b planes using N EWarer, including a tour of che site. The afternoon also involved a visit co PUB-One, che Woodleigh Control Centre Complex, with presentati ons on demand management, the call centre (utili sing telephone, e- mail , sms, fax, li ve web char and Voice over IP), leak detection and a tour of the meter workshop. Ensuring chat we all experienced some of what Singapore had co offer in ch e way of nightlife and entertainment, we piled on the bus and had a tour of the city. A fabul ous dinner on hoc rocks and a brief sto p at the night markers were a highlight and no crip would be com piece without che peanu ts on the floor and Singapore Slings at Raffles. The second day of the tour cook delegates co rhe Changi Water Reclamanon Plane (CWRP), th e cornerstone of the first phase of che Singapore Deep Tunnel Sewerage System (DTSS) project. T he DT SS was conceived as a long-term solution co meet th e needs for
The Australian TECHNOtour Delegates outside the PUB NEWater Visitor Centre.
used water collecti on, treatment and disposal. Implemented in phases, the entire construction will consist of two large, deep tunnels crisscross ing the island, two centralised water reclamation planes, deep sea outfalls and a link-sewer network. The 2 deep rnnnels will have a diameter of up co 6 metres and will be built at depths ranging from 20m to 50m metres below ground. Treated effluent from the CWRP will be conveyed through the omfalls and discharged through a se ries of diffuser heads to facilitate dilution and dispersion of the effluent in the receiving sea wa ter. After the immensity of the CWRP, delegates were treated co a lunchtime netwo rking fun ction with the newly fo rmed Singapore Water Association. Different co AWA, in the fac t chat they are interested in corporate members only, there were sti ll many synergies and opportunities fo r both of the Associations to work closely together. The Singapore Water Assoc1at1on was especially interested in th e T ECH N Ocours and caking delegates from Australia and Singapore together. T he final tour fo r Singapore was co che T uas Desalination
Plant with a session briefin g and tour. PUB is looking to secure 136,000 cubic metres of desalinated water per day by the year 2005. Designed as a Build Own-Operate (BOO) project, PUB awarded ch e tender in 2003 for commencement by che second half of 2005. Overall, all 16 delegates agreed chat th eir objectives were met and felt chat che ability to visit and talk with the people
Many thanks to the TECHNOtour Sponsor, CH2M Hill - their support ensured the TECHNOtour was a success for all involved. CH2M Hill, PO Box 5392, Chatswood NSW 15 15, Tel: 02-9950-0200, Fax: 02-99500600, Email: Stephen.Chapman@ch2m. com.au, Web: hccp://www.ch2m.com.au CH2M HILL Australia is a fu ll solution, service and project delive1y company. We are a market leader in managing water, wascewacer and environmental issues, maximising our clients' recurn on invesrmenc in sustainable infrastruccure projects. In Australia we are a recognised market leader in:
behind the scenes is a rea l advantage of the TECHNOcours formula. Further information for the s ite visits is available on ch e PUB website ac Imp://www.pu b.gov.sg. Otherwise, to ex press interest in the nex t Singapore T ECHNOcour, please contact C lare Porter directly on cporte r@awa.asn.au.
CH2MHILL • Advanced technology solu tions • Consulting programs • Project and construction management. Globally we work with clients in 75 countries and have built a reputatio n for leading the market in advanced technology solutions over the past 57 years. We achieve chis through a 16,000scrong team, who combine proven approaches with innovative thi nking. CH2M HILL will help you co imagine, design and build a better wo rid.
water
MAY 2005 29
water supply
WATER TREATMENT ALLIANCE P Mosse An Australian Partnership for the Optimisation of Water Treatment The latest ed ition of the Australian D rinking Water Guidelines (released in draft form sin ce 2002 and in its fi nal fo rm in Decem ber 2004) incorporates a Framework for the Management of D rin king Water Quality. This is a new development in chis country and one which rakes the emphasis in managing d rinking water q uali ty away from the traditional m onitoring o f p roduct water qual ity. Instead the new framework in troduces a catchment to rap philosophy char aim s ro identi fy all h azards char may be p resent in rhe system and may pose a risk to human health. T he strategy also iden tifies preventive measures char are in place to reduce or eli m inate the risks and puts in place monitoring at control points along the way, from catch m ent to tap, to ensure chat water quality is mainta ined within cri tical lim its. In chis way water providers can ensure that h igh quality water is produced cons istently, without having to rely principally on monitoring of the fi nal prod uct quality. In Victoria, the Safe Drinking Water Act (20 03) moves chis preventive managem ent approach into regulatio n with a requ irement fo r all V ictorian Water Authorities to p repare system specific Risk Managem ent Plans, consisten t with rhe ADWG Framework fo r The Management o f Drin king W ater Quality. This new approach, enshrined in these docum ents, has created a flu rry o f activity withi n the Australian Water Indust ry with a focus on all steps in the produ ct ion of d rinking water. T he water treatment p rocess is integral to the provision of safe d rinking water and therefore, water quality managers are considering ways to optim ise the operation o f Water Treatm ent Planes to ensure consistent h igh quality water is produced. Indeed che Water Treatment P lan t encompasses several key control steps in the sequence fro m catchment to rap. The Water Treatment Alliance (WTA) is a continuous improvement program for the management of Water T reatmen t Plan ts. The Alliance is based o n the Partnership for Safe Water administered by the American Water Works Association. T h e Water Services Associatio n of Australia, the Australia n Water Associatio n and the Cooperative R esearch Centre for Water
30 MAv 2005 water
Quality and T reatment jointly adm inister rhe program in Australia. The m ain aims of the W T A are to: • continually improve performance; • optim ise the operation of water fi ltration plants; • bench mark with international plan ts; and • com plement technology transfer mechanism s fo r C RC Research. T he program com menced in Australia in J uly 19 99. A p ilot study was conducted with th e objective being to establish a cost effective program based on the proven experience of the Am erican Partnersh ip and to adap t it to Austral ian conditio ns. A key objective was to determ ine whether the program should be adopted in Australia . To chis end five ucilicies trailed the program over a period of 6 m onths. A fi nal report recom mending the adoption of the program in Australia was submitted in May 2000 The full Water Treatment Alliance program comm enced in May 20 02. Ar present a total of 14 Authorit ies, widely distribu ted around Australia, are registered with the Alliance.
per iod with a m aximum turbid ity of <0.3 NTU for no longer than 15 min utes . T he initial phases of rhe W T A involve establishing a comm itment to rhe program (sounds a b it like Element One of The Framework, doesn't ir!!!} and fam il iarising both operational and management person nel with the process. T his is best achieved by establishing an "Al liance Optim isation Team". Every effort should b e made to include a senior managem ent representative on the ream to ensu re char the program is fully integrated with other management p ractices . O nce a commitment has b een made, and a team estab lished, the first step is to col lect and analyse 12 months turbidity data in derail. Historical data may be used if it is availab le in sufficient derail. Alternatively new data is collected for raw water turbidi ty, settled water turbidi ty and fi ltered water turbid ity for each individual fi lter. O n line turbidity mo nitoring is strongly recommended for each fi lter and preferred for raw and settled water, however if on line meters are nor available then measurements using a portable turbid ity meter are satisfactory. Ar
A partnership to improve water quali-ty regardless of the size of the town. So What Does the WTA Do? The WTA p rovides a structured way to assess rhe current operational characteristics of a Water Treat ment Plant and provides a mechanism whereby the deficiencies of a plant can be identified. Once identifi ed, the p rocess provides a mechanism to identify ways to overco me the deficiencies, prio ritise work necessary to improve the operation of the plant and to monitor that improvement. T he steps are exactly analogous to chose described in rhe Framework fo r the Management of Drinking Water Quality where hazards and p reventive measures are identifi ed and the preventive measu res assessed as to whether they are sufficient to red uce or eliminate the hazard. If they are nor, alternative m easures or mod ified measures are identified, prioritised and im plemented . The WTA also provides best p ractice rargers fo r WTP operation . For examp le, best p ractice operation of med ia fil ters should result in water with a turb idi ty of <0.1 NTU at all rimes except fo r a ripening
this early stage in participation the need fo r additional equipment, in particular tu rb idity m eters, may be identified ro allow the collection of rhe necessary data. The fi rst 12 mon ths data establish es a baseline to allow assessment o f the impact of the WTA program on the system. Subsequent annual reviews of current performance can then be compared to this baseline. Once the baseline d ata is collected, and co ncurrently with the collection if the Water Authority so chooses, a review of p lant operation is carried our using the "Self Assessment" m anual. The Self Assessment man ual is a well written and factually excellent book with a wealth of information to help optim ise treatment plant operation. The review aim s to identify areas limiting performance and to develop a sire specific plan to im prove the plan t. The review includes an assessment of each o f the major u nit processes in water crearmenc, fo r exam ple filtratio n and disinfection. I s the design of the plant com pat ible with best p ractice and current
water supply hydraulic loads? A self assessment report is then submitted co and reviewed by extern al specialists and feedback provided to the Au thority. Turbidity data is collected continually throughout the process and analysed at 12 monthly intervals against the baseline data origin ally coll ected. As the items identified in th e self assessment program are implemented there should be a progressive improvement in plane fun ction. T he WT A software uses curbidiry spike analysis as a useful measure co monitor performance. Indeed such a measure could easily be incorporated as one of rhe measures in the im plementati on of the ADWG Framework and would make an excellent measure co report progress with Water Treatment Plane opti misation co senior management. T he WTA relies heavily on curbidiry data and that might give the impression chat che program focuses primarily on fil ter fun ction. T his is defi nitely not the case. The program focuses on all th e seeps invol ved in the effective operation of a Water T reatment Plant incl uding for example, administrative and management limitations, coagulation and flocculation , sedimentation and disinfection ... a th oroughly well roun ded approach . By monitoring in detail, the incoming curbidiry as a surrogate measure of raw water quality, and then serried water and filtered water curbidiry, it enabl es the parti cipant co fully assess the effectiveness of the coral plane under all raw water conditions. The WTA strongly recommends that conti nuous on line moni tori ng is used for the raw water and for th e filtered water from each fil ter. This approach again is completely consisten t with the ADWG Framework where similar recommendations for the continuous monitoring of operational parameters is made.
Ac the end of the second year a second annual report is submitted co nsisting of a furth er 12 months of data. T his allows the external reviewers co monitor progress and perhaps make additional suggestions. Dara collection th en continues throughout the period of self improvement and provides the measure of rhe success of th e program. O nce the optimisation period is over, the data collection and reporting component may still be used co demonstrate compliance with che targets and the production of consistent, excellent quality water. In the United Scares, the Partnership for Safe Water has an award scheme based on che continui ng abiliry co provide such water, however whether such a system will be adopted in Australia remains co be see n. T he WT A is largely a self help co ntinuous improvement program and as such is administered within the participati ng Authori ty. Support is provided by a Project Manager should it be required. Recently a wo rkshop was held in Sydney fo r participants and interested parties to clari fy issues and ensure that all parti cipants were using the cool in the way it was designed. Th ere are also plans co run workshops aimed at providing guidance in specific aspects of Water T reatment Plant op timisation. T he first of these is likely co be on fil ter monitori ng
and optimisation. T he aim is also co set up support netwo rks co allow more advanced Authorities co provide expertise and support co Authorities without specialist technical skills. The overall aim , as with th e ADWG Framework for the Management Of Drinking Water Quality, is co bri ng about actual improvement in water qualiry supplied co che peopl e of Australia wherever they may be and regardless of the size of the town where they live.
So Why Consider the WTA? T he design and implementation of the WT A is completely co mpatible with the ADWG Framework and HACCP programs. Alth ough all the seeps can be done independently, the WTA imposes rigor on the process by having firm requi rements fo r data collection and reporti ng, and offers the opportunity for special ist review. Too often programs are commenced and lose momentum because of workloads and ocher requirements. T he external component of the WTA aims to assist in achieving continuous improvemenr. So if you are interes ted why not fi nd out more ... contact Peter Mosse at peter.mosse@gippswacer. com.au or Peter Donlon at peter.donlon@wsaa.asn.au
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water
M AY 2005 31
water supply
m
INCIDENT MANAGEMENT IN PRACTICE B Ashworth Abstract This paper describes a major contamination incident affecting the water supply to a country town. T he fact rhar emergency plans had been prepared and filed on CDs enabled a rapid response from staff, even at a weekend.
Introduction Leongarha is a country town in Victoria, with a population of about 5000. Ir is supplied with water by South Gippsland Water, which is responsib le for water and wastewater services to over 20 towns and rural areas along the South Gippsland coast and ranges.
The Contamination Sometime during the night of Friday 23 November 2004 an irrigation pipe carryin g supernatant from a dairy shed effluent po nd burst. Th is resulted in approximately 2-300,000L of contaminated water being discharged to Reservoir No I ( I ? ML) the final storage before the treatment plant. See Figure 1.
Detection of Contamination T he contamination was initially detected by the chlorine residual monitor located a few metres downstream of the water treatment plane dosing point indicating rap id loss of residual. On checking the plant the operator noticed a significant increase in raw water rurbidity. Initial investigation at the reservoir revealed a noticeable smell and furth er investigation located the source of contamination.
Western Reservoir (No. .4 )
--
Hyland Reservoir (No. 3) No. 2 Reservoir No. 1 Reservoir
SOURCE: Ruby Creek
"'"'""
TREATMENT: Full treatment with alum, potassium permanganate, powdered activated carbon , soda ash, ch'4)r'ine (gas). coagulation . :sedimentation, filtration, chlorination aeration at all rese<Voirs POPULATION: Estimaled Leoogatha 4.600- sewered. Koonwarra '40 . not sewered.
rural
LEONGATHA
=¡.'==--~--''---- tf!',/71/-' users '
,~~-,. KOONWARRA
-tfttt
~ sers
chlorine gas
STORAGES:
No. 1 Reservoir . earthen, open, 19 ML No. 2 Reservoir . earthen, open, 84 ML Hyland Reservoir (No. 3 Res) - earthen, open, 671 ML Western Reservoir (No. 4' Res) - earthen, open, 1,137 Ml 3 Clear Water Storages - concrete, roofed, 5.6 Ml, 1.7 ML & 1.6 ML
Figure 1. The Leongatha water supply system.
valves on the raw water line berv,een the reservoir and plant. Th is was continued until the treated water sto rages had dropped to the level that required the plant to restart. When the plant ini tially restarted the treated water turbidity rose to l .9NTU. Conti nuing problems in maintaining a
chlorine residual lead to slug dosing of the treated water sto rages. During this time flushing of the reservoir continued by spilling flows. By mid afternoon of the following day the turbidity was back to < 0.2NTU with a constant residual. O nce the treated water sto rage were calculated to be filled with
Access to emergency plans on a CD meant no delay in response.
Actions to Minimise Contamination and Restore Water Quality The initial action was to stop the plant. Flushing of the affected reservoir then commenced by increasing the discharge rare from the upstream reservoir and openi ng T his paper is an edited version of a prescntarion by Brian Ash worth to the Workshop, held in April in Calgary, Canada, on the American \Y/WA Research Foundatio n Project: " Risk Analysis Strategies for More Credible and Defensible Urili ry Decisions" . South G ippsland Water is a partner in th is project.
32 MAY 200s water
Leongatha No l Reservoir.
refereed paper
water supply good quality water, flushing of the system commenced. Protecting the Public Following discussions with the Department of H uman Services a bo iled water alert was confi rmed as essential early on the Saturday morn ing. Conracc wirh radio stations was dealt with by the Department. The prin cipal aims were to ensure the public was warned and provide alternative water supplies befo re the concami narion reached the town system. fn order to achieve chis the Municipal Emergency Plan was acrivaced to provide additi onal resources. A boiled warer notice was printed from a standard fo rm. T he cou ncil then printed and organi sed volunteers to hand deliver to all properties by the lace afternoo n, T he council also provided staff ro man th e warer ranker sires fo r the first 24 hou rs. South Gip psland staff were occupied by: • Dealing with co ntamination • Notifyin g major customers, hospita ls and fo od premises • Organ ising water cankers • Dealing with phone queries
Municipal emergency incident room .
• O rga nising additional testing • Continui ng to operate th e remaining sys rems As schools serve areas outside rhe Leo ngarha area it was necessa ry to provide alternative dri nking water supplies ro schools by Monday morn ing. T his was achieved by installi ng small warer ranks ar all rhe schools.
Operational Manuals and Incident Management Plans Comprehensive emergency incident plans had been prepared following a risk evaluati on carried our in 2003. T hese were all contained in an O perations Manual CD so chat they were available to managers at home outside normal operating hours. Plans used incl uded:
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refereed paper
water
MAv 2005 33
water supply • T he South Gippsland Water Emergency Plan • Catchment Emergency Incident Management • Department of Human Services Liaison • Police Li aison • Acrivarion of Municipal Emergency Plans Alrernarive Water Supplies • Prepared leaflets on Boiled Water Alert
Microbiological Results Viab le Cryptosporidium and Giardia cells were identified in rhe reservoir on Saturday. Non viable Cryptosporidium and Giardia cells were identified in rhe rreared warer on the Sunday only. No £-Coli cells were detected in the created water or the reticulation system
Alternative water supply provision.
DIARY OF EVENTS
Media Coverage/Public Opinion Friday 23/11/04
Although the headl ines were dramatic the articles and public quotes were positive. • LEONGATHA WATER IS CONTAMINATED - South Gippsland
Plant running 60L/sec T urbidity: treated >0.2, raw 2.03 Chlorine residual 1.1mg/L
Sentinel Times
Saturday 24/ 11/ 04
• H EALTH ALERT AFTER ' GATHA WATER FOULED - Great Southern Star • "South Gippsland Water did all they could." - Owner of Koonwarra Store Cafe • "I would like to give credit to rhe Water Authority for rhe way they have handled ir, Grear Work!" - Primary School Principal • "South Gippsland Water brought us a container of fresh water, and looked after us very wel l. Ir's a nuisance, bur we' re lucky we don' t have to do ir all rhe rime." Child care centre coo rdinator
07.45 Plant Alarm Chlorine residual 0.7mg/L. Also Turbidity: raw 9.0, treated 0.2, 08.15 Storage quality checked. Plant switched off and management contacted 09.35 Confirmed that problem was due to irrigation system using dairy effi uent supernatant. 10.36 DHS confirm Boiled Water Alert 10.40 Activate Emergency Plan 11.00 Started Flushing reservoir 11.20 Send prepared Boiled Water alert to DHS 11.40 Activate Municipal Emergency Response Team. 13.00 Boiled Water notice issued to Municipal Emergency Response T eam for printing and distribution by door knock. Water rankers on sire in town. 18.00 Boiled water notices all distributed 22.30 Treatment plant starred to meet demand
Conclusion Early detection of rhe contamination and effective emergency procedures resu lted in all consumers being advised of rhe problem in advance of contaminated water entering rhe system. Although it is probable that so me contaminated water entered the system there was no presentations to the docto rs or rhe local hospital that could be attributed to the contamination. Although the incident occurred during the weekend the abil ity to access the emergency plans from a CD meant that there was no delay in response. Integration of the Municipal Emergency System into the Plan ensured adequate resources were available in a timely manner. T he effectiveness of the co ntingency plans resulted in minimal adverse publi city to Sourh Gippsland Water.
The Author Brian Ashworth is Operations Manager, South Gippsland Water, bashworrl1@sgwater.com. au.
34 MAY 2005
water
Sunday 25/11/04 00.01 T reatment plant performance srarrs to deteriorate with turbid ity rising almost to 2NT U and difficulty in keeping chlorine residual 08.00 Storages slug dosed with Sodium Hypochlorite to maintain residual to town. 14.10 Turbidity under control (below 0.2 NT U) and chlorine residual stable 14.30 Commence installatio n of drinking water ranks for schools
Monday 26/11/04 07 .00 T urbidity below 0.1 NTU stable chlorine residual. Suspect water will now have been replaced by normal quality water in storage. 10.00 Normal quality water estimated to be entering the system. Flushing system started 14.30 DHS Discussion about mechanism fo r removing boiled water notice 19.30 Flushing Completed.
Tuesday 27/11/04 07.00 16.50 17.00 17.30 19.00
T urbidity below 0.1 NTU, stable ch lorine residual. Monday C rypto results received, All Clear Boiled Water Notice Lifted ABC news reporrs boiled Water Notice lifted Distribu tion of Leaflets to pubs, restaurants etc
Wednesday 28/11/04 am
Leaflets being distribu ted to Town through Mail
refereed paper
Just add water
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MEMBRANE TECHNOLOGY Adelaide, March 2005 Reported by Bob Swinton This international conference was opened by Professor T ony Fane (UNSW) on the cheerful note char che cost of desalination of seawater by Reverse Osmosis could soon be down to 50 c/kL and membrane purification of wastewater to even less. ie 30c/kL. T he conference organisers had invited a number of keynote speakers from Europe and USA and combined with papers from Australians rhey gave a thorough review of membrane tech nology, both applications and research.
Reverse Osmosis Prof. Enrico Drioli, Director of rhe Italian IRMERC, a Division of the CNR (the national research institute), who is the Foundation President of rhe European Membrane Society, reviewed the currenr status of sea water desalinati on by Reverse Osmosis (SWRO), compared it to char of the thermal planrs, and followed this by his forecasts for the future. Capitalisi ng on the vase im provements in membrane technology chat have chat been accomplished in the past 25 years he foreshadowed even more cost reductions and reliability (see Table 1). There will undoubtedly be improvemen t in the membranes, coupled with improvement in the systems, the conractors, che reactors, and most of all, by integration of the processes of pre-treatment.
"even more cost reductions and reliability" Total costs have fallen from $US l. 5/kL in 1994 to $US0.55 kL for big plants(> 110 ML/d), $US 0.85 for 40 ML/d, bur are still over $US 1.00 for smaller planes. T his has been ach ieved by the fall in the price of commercial membranes from about $ 1000/ m 2 to about $80/m 2 , and bigger membrane mod ules which reduce rhe coses of pipi ng and civi l works. (Fo r small plants we need to redesign membrane modules to simplify civil works). T his has been accompanied by a huge red uction in energy consumption (typically 44% of cost) as better rejection characteristics of the membranes enable desalination by single pass, with 45-60% recovery now possible. The most recent large planes have energy
36 MAY 2005
water
Table 1. Progress of SWRO. History
1980s
1990s
2000
Recovery Energy Operoting press mPa Product quality, mg/L
25 12 6.9 500
40-50 5.5 8.2 300
55-65 4.6 9.7 200
consumptions as follows: Ashkelon < 4 kWh/kL; Spain, 3.1-4 kWh/kL; Cyprus, 3.4 kWh/kl. Key facto rs for furth er im provements are: water recovery, capital costs, water quality, brine disposal. Disadvantages of SWRO: • Seasonal variations in seawater quality • The need fo r frequent chemical clea ning • Sensitivity of the membranes to fo uling by colloids, hydroxides, bacteria • Damage by oxidisi ng compounds and bacteria • Scaling by calcium, magnesium , barium , even strontium compounds. Thorough pre-treatment of the feed water is essential, co nventionally a combination of fi ltration and chem ical pre-treatment. However, micro-filtration, ultra-filtration and nano-filtration are now being applied.
Currently there are seven MF/UF manufacturers and costs of membranes are competitive. MF/ UF systems for 8- 12 ML/d plan cs are typically US $120/kL of capacity, reducing to about half chat for large planes. Table 2 compares the characteristics of UF pre-treatmen t with conventional coagulation/ filt ration. Nanofi lcration has the ability co reduce hardness, removing 90% of the mulrivalenc sales rhus allowing mainly monovalent sales to pass through co the RO unit. Th is has enabled the recovery factor in RO to be increased, with less scaling. There are also investigations in ptogress at Long Beach on rhe use of rwo stages of NF alone, which have prod uced potable water with a total recovery of 37%, with lower energy costs and less pre-treatment problems than RO Brine disposal is a significant problem, even in coastal sires. In the furure there will be progress on recovery of chemicals from rhe brine, with potentially saleabl e products, and increased recovery of fresh water. This theme was expanded on by Yoram Cohen in a lacer presentation. Prof Drioli also introduced membrane processes other than SWRO, such as ceramic membranes, which are solvent proof, suitable for chemical manufacrure
Table 2. Comparison of pre-treatment systems.
Water quality
UF Pre-treatment
Conventional pre-treatment
SDI < 2.5, l 00% of the time, usually < l .5
SDI < 4 N90% of the time
Consistent, reliable quality
Fluctuating quality
Positive barrier to particles and pathogens . no breakthrough
Not a positive barrier to colloidal and suspended particles
Turbidity< 0. 1 NTU
Turbidity < l .0 NTU
Bacteria > 5 log removal Giardia > 4 log removal Vi rus > 4 log removal Typical lifetime
UF Membranes 5-10 years
Filter media 20-30 years
Cartridges often not needed
Cartridges 2-8 weeks
Average RO flu x
N
SWRO replacement rote SWRO cleaning frequency Pre-treatment foot-print
N
N
18 lmh
l 0% per year
1-2 times per year
N30-60% (of conventional)
N
N
14 lmh
14% per year
N4- l 2 times per year Nl00%
from P H Wolf and S Sievers, International conference on desalination costing, 6-8 December 2004
The future is and are able to tolerate high cemperacures. Micro-porous hydrophobic membranes for mem brane distillation may also become comperirive with SWRO. The concept of membrane disrillacion was described in more derail by Roger ben Aim, of LIPE/IN SA, Toulouse. le is a completely differe nt co ncept fro m RO. The membranes are microporous and highly hydrophobic and will only allow water vapour to pass ch rough to che low-pressure side. The brine side can be allowed to co ncentrate almost to supersacuracion although crystallisation muse nor be allowed to rake place on che membrane bur in a sepa rate vessel. Very high recovery can be achieved. T he process has been studied for som e years, and despite rhe difficulty in manu faccuring such membranes and the need for higher membrane area, the energy consum ption is much less rhan for RO, and ir may have a niche for desalination if operated ar a high cemperacure, coupled with solar energy. R& D on such membranes has rhe potential to vascly increase the flux. Yoram Cohen, Director of the Polymer and Separations Laboratory, UCLA, spoke on a possibl e solution to the prob lem of brin e disposal. For example, authorities are co nsidering a huge proj ect in Southern Californi a where it is proposed to blend 700 ML/d of agriculcural drainage water, 5000 mg/L T DS, of which 1200 mg/L was sulfate, with 1100 ML/cl of river water and desalinate for re-use. T his would produce 80- 120 ML/d of bri ne, and to dispose of rhis by drying beds would require huge areas. UCLA's R&D aim is to increase recovery to 95% which would mean char the brine would be co ncentrated by a facto r of 40. T his is obviously imposs ible by normal means since sca ling wou ld occur long before rh is degree was reached. T hey are operating an RO pilot plane on high-salinity Colorado River wa ter and have shown rhac the first srage co ncentrate co uld be treated by "Accelerated Seeded Precipitation " to rake our CaCO3 and other salts. Experiments in labo ratory-scale reactors indicate char rhi s could be accomplished in reasonable sized reactors. Following such cryscallisacion rhey ran a second stage RO but using rhe membranes in a plate and frame mem brane fo rmat so char rhe sca lin g could be observed. In three years of R&D they achieved (o n brackish water) 90-96% recovery wirh the possibility of98%. If ap plied co che project mentioned above, ir would mean char in stead of huge brine evaporation basins, with their environmental impacts, there wo uld be 70-80 truck loads of solids leavi ng the area per day, some of them with saleable product. Another keynote presentation was delivered by Nikolay Voutchkov, Vice Pres ident of Pose idon Resources Corporation of USA, a major contractor for SWRO. His ride was "From Research to Environmental Permitting, Construction, Starr-up and Operations... Managing rhe Project and che Process". C urrently there are 17,000 SWRO plants in 120 countries, supplying about I% of the world's drinking water supply and projected ro double by 20 15. He main tained chat the cost of SWRO is virtually rhe same as rhe production of potable water from wastewater particularly if the latter co ntains low MW pollu tants such as NOMA or perchlorate. His perspective on rhe advances in rhe past 20 years is rhar membranes have improved dramatically. Salt passage through rhe membranes is now down to only I 5%, char is, a single pass wi ll now produce fresh water, flux has doubled, and the useful life has also doubled from 2-3 co 5-7 years. Energy consumption is down co 20% due co energy recovery systems. That, together with economy of scale, larger membrane modules, less SS piping, larger RO pumps (now offthe-shelf) , BOOT delivery, co-location of in cake and outfalls with power planes and automation have all reduced coses. What of the fucure? Smart membranes, greater integrity, selective salt removal, improved cleani ng and restoration of fo uled membranes, nonmetallic materials fo r high pressure piping, reduced pre-treatment costs
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MAY 200s 37
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as MF becomes com modified . Energy recovery will advance from the Pelton wheel to ceramic pressure exchange, and perhaps NaCl can be taken out of the water rather than water our of the NaCl. There are prospects fo r commercial development of the concentrate scream for chemicals such as magnesium salts. H e estimared char costs will be lowered to the extent char by 2020, SWRO will be 1020% of every coastal water utility's portfolio. His thorough review of proj ect implementation covered facto rs such as water quality, both of the seawater intake (considering factors such as red-tides and sil t disturbance by shipping and dredging), the options o f deep water in takes, o r beach galleries, which in effect utilise a natural sand filter, or best to co-locate with the intake and outfall of cooling water for a power plant. The quality of the product should be tailored for its use, mentioning boron as a potential problem. Choice of sire wi ll incur the inevitable NIMBY (coastal zones are precious) and h is review consid ered all the environmental impacts of the plant itself and its necessary traffic together with consid eration of all the factors involved in the safe disposal of the brine and clea ning waste back to sea. One slide p ut the power requirement for SWRO into focus. Conventional water treatment uses 0.4 to 0.6 kWh/ kl, brackish RO 0.7 - 1.2, wastewater reclamation 0.8- 1.0, and SWRO 3-5 kWh/ kl. T har may be the highest bur to supp ly water to the typical (American) famil y would use the same amo unt of power as consumed by their refri gerator. Finally he reviewed the designs of the recent major SWRO installations. Altogether, his 70 slides were a mine of practical information. In a subsequent session Nikolay was persuaded to give us ' the low-down' on the troubles with the Tam pa Bay SWRO proj ect. These have been reported by D iane Wiesner in our March issue, and to summarise, the problems were caused by mismanagement, nor technology. Prof Rafael Semiat, Director of the Grand Water Research Institute, Israel, described the tremendous efforrs char Israel has applied over the years to supplying water by both seawater and b rackish warer desalination . Various d istillation systems were developed , bur rhe policy is now to concentrate o n RO . Eilat, situated at the head of the Red Sea, can exist solely because desalination plants supply 85% of its consumption: 35 M L/d fro m brackish water and 10 M L/d from the sea, and it houses the N ational Laboratory fo r D esalination, with a wide variety of p rojecrs bo th for SWRO and wastewater reclamatio n. O ne project focuses on boron, and va rious treatment trains have been investigated. It may be necessary to use a boro n-selective IEX resin to produce water sui table fo r irrigation. T here has been a strong attack on the p roblems of fo uling, and one project trials the dynamic addition o f anti-sealan ts and even recycling o f anti-sealan t. Taking ano ther direction, H arry Seah , Director of T ech nology fo r Singapore's NEW acer proj ects, b egan by stating that NEWacer, from wastewater, was o nly on e aspect o f Singapore's po rtfolio. They are installing a 50 ML/d seawater RO and converting a tidal estuary into a freshwater reservoir fed by stormwarer run-off from high ly urba nised area, which will have to be treated. The NEWarer plants consrirure a train of MF/UF and RO units, operating currenrly on secondary created wastewater and producing po table water. C urrenrly abo ut 10 M L/dis returned to the potable reservoirs but most of it is sup plied to industry, and the electro nics wafer industry has even more stringen t requirements than potable quality, so an Ul tra Pure Water P ilot Study was co mm en ced in
2001. The Public Utilities Board R & D program includes 3 pilot planes of 300 kl/d, and they have demonstrated that membrane bio reacrors are consisrenrly b etter than conventional secondary
38 MAv 200s water
acrivared sludge, so rhar rhey will be operating a 20ML/d demonsrrarion plant in 2006. O ne aspecr is co integrate anaerobic and aerobic creacmenr wirh membrane technology. T hough not ' international' in che sense char rhey were on home territory, che contri bution "A road map for the nexr generati on of water recycli ng planes", from Greg Leslie, Tony Fane and co-workers at che UNESCO Centre at UNSW merited keynote scacus. Prof Greg Leslie contrasted che mammalian kidney with the best of current technology. Despite the huge advances in the past 25 years, we are orders of magnicude less efficient than the kidney, which consists essentially of a microporous basement membrane which fi lters the blood cells fro m the serum, fo llowed by tubules which acr as a semi-permeable membrane, operating ar a typical rare, fo r humans, of l 40 Lid ro fo rm I Lid of urine. The power requirement is one-renrh of the best we can achieve so fa r. The besr synrheric hollow fibre membrane modules can pack so me 500020,000 fi bres inro a module about a metre long and, say, 0.3 m diameter. A kidney, roughly 0. 1 m long and 0.05 dia meter,
co nsists of a uniform pack of about 2.6 million tubules, each 2-3 mi crometres in diameter. Th e key difference fro m RO technology is char instead of retaini ng the sal ts and allowing water co pass through, the biochemistry of the cubules accually pumps the salts, urea, etc through to the uri nary tract. Of course, rhe tubules are living entities which are continually replaced rhroughour healrhy life. We may not yet be able ro mimic the biochemistry which achieves rh is, rhough there is work in progress, but we can at least aim to design better membranes and better membrane arrays with uniform pore size and distribution.
Wastewater Reclamation, the MBR story A shift from desalination to recovery of high quali ty water from wastewa ter was signalled by another international contribution fro m Roger ben Aim, from [NSA, Tou louse, who discussed rhe porenrial for hyb rid processes, where rhe characteristics of rhe membrane srage affecr rhe design and operation of rhe pre- and posr-trearmen t. Fo r example, rhe membrane bio-reactor increases rhe efficiency of rhe activa ted sludge stage by enabling a much
higher sludge residence time ro be main tained. At the same rime, the higher bio-degradarion efficiency reduces the colloids which woul d clog a subsequent membrane process. Of course, the membrane modules have had to be redes igned for this specific task, with opti misation of the bubbling system, and study of membrane fo uling. The largest MBR plant is currently 80 ML/d and the future fo r dece ntralised systems is bright, e.g. sewer mining and recycl ing within a commercial bu ild ing. Coupling anaerobic reacrors with membranes is one of the current challenges. Another area of research is the immersion of a membrane separaror within a coagulation unit, requiring a new optimisatio n of the flocculation dynamics. Similar coupling of activa ted carbon adsorption with membranes has been developed, and Vigneswaran of UT S gave examples from their own wo rk. Boris LeJean of Veolia Water reviewed 12 years of operati on of the BioSep process, one of the original M BR processes. He gave an impressive descripti on of many successful plants cackling ind ustrial effluents, fo r examp le the largest MB R plane on an abacro ir in France, deali ng with 1000 kL/d
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MAY 200s 39
containing 2000 mg/L COD, reducing it ro COD 25, BOD 3, TKN 5, Total P zero, and a seafood processor where the effluent is the same salinity as seawater. With th e advantage of actually operating the planes they installed, in rwelve yea rs since the first pi lot plane in Adelaide they have reaped a harvest of practica l knowledge with regard to aeration, maintenance and recovery cleani ng.. Current development projects include a thorough investigation of foul ing, finding by LC-OCD analysis chat MBR removes polysaccharides and proteins, but passes humics and low-molecular co mpounds, and there is a correlation between the polysaccharides and rhe degree of foulin g. He gave a useful cable of the removal efficiency of MBR fo r various pharmaceuticals, the low molecular weight ones being only parrly removed, however, there is excellent removal of oesrrol and ocher steroid hormones. Current developments are foc ussing on combining BNR with MBR, also discussed by Anja Drews of Berlin UT.
Costing Pierre Core, Zenon ln rernarional, presented an excellent cost co mparison between SWRO and reclamation of wastewater, produced either by conventional BNR activated sludge, followed by tertiary fil tration then RO , or by membrane bioreaccor. followed by RO. T he cost of the initial biological purification is not included si nce ch is would have been necessary anyway. In simple terms, for a 38 ML/d plant, capex for SWRO would be 944 US $/kL/d compared co 482 for the wastewater reclamation, and O&M is similarly hal f, so chat the life cycle cost in coral would be 0.62 c/kL for SWRO compared co 0.28 c/kL. He emphasised chat these figures are valid for relative compariso n purposes, bu r actual val ues could be Âą25%. His paper included sensitivity analyses and projections of future savings in SWRO, but the outcome was still clear, it is cheaper to scare with the lower salinity of wastewater. Another presentation from Zenon by Arnold Janson outlined the details of the 45 ML/d MBR installation on the Nordkanal, Germany, which receives effluent from 80,000 ep. The UF membrane modules (84500 111 2) are immersed direcrly in the bioreactor. As well as the better quality of effluent, the small footprint alone has saved the authority some 5% of rhe E.25M capital cost. 350-400 m-~ of sludge is wasted daily (25 days SRT) gravity serried to 27-30 g/L, centrifuged to 25-27%, rhen burnt in a nearby power station.
40 MAY 2005 water
They chose UF instead of MF because of rhe presence of emulsified oil, but Arnold main rained chat in practice an MF membrane exposed to the MLSS would have ' tightened up' sufficienrly to do the job.
Cleaning the Modules Olivier Lorain, from Polymem, Toulouse, described current developments in hollow fibre technology. Initial MBR technology used large diameter fibres through whi ch the MLSS was pumped at high velocity, bur apart from small domestic insrallarions they were superseded in the 1980s by the 'outside- in' submerged modules, agitated by the air bubbles. T hese are relatively low priced bur repair is impossible. T hey are developing a UF module which is fed from the activated sludge rank via an intermediate gravity seeder. Membrane flux is much higher and less air is used for scouring, so chat aeration of the activated sludge can be operated independenrly. Maintenance is much easier. To ny Fane (UNSW) reviewed the role of the air bubbles in MBR which, as well as supplying rhe oxygen required by the biochemistry, provide rhe shear and movement of th e fibres which co ntrol floe deposition and fouling. His ream at rhe UN ESCO Centre fo r Membrane Science and Technology have used Particle Image Yelocimerry, (using laser photography) to observe the shear right into the centre of a model bundle of fibres. T hey are studying intermittent versus co ntinuous air bubbling and optimising fibre geomerry,cycle rimes and flux rates. On the engineering side, the UNSW ream is looking at how membranes fail, and the efficiency of cleaning and poren rial damage, particularly during air scour, when rhe fibres sway about. The engineering design of the weakest link, i. e the joints berween rhe fibres and rhe potted ends is being studied in derail. Biofouling can exist at two levels in MBR plants and Prof, Grasmick and his team at rhe University of Montpelier are studying the co ntro l of 'clogging of rhe mod ules' by biomass floes as well as membrane surface fo uling. They compared a standard immersed module with a side-stream membrane module with an air-life to bring rhe MLSS in co ntact with the bundle. They have tried addition of FeC13 and PAC which modifies the floe scrucrure enabling chem to operate fas ter and longer. This paper elicited lots of discussion from rhe UNSW ream.
Some Australasian Projects Jaso n Colron, of CH2M Beca Led, New Zealand, gave details of the Waikato water
treatment plant expansion. The design incorporated UF treatment by Zeeweed immersed membranes, following screening and lime coagulation, rhe product being further created by GAC, NaOCI, fluoridation and srabilisario n. UF was chosen because of the potential for pathogens, high algal counts in summer, arsenic and DBPs and also of chemical sp ills because the river passes through agricultural and industrial areas. Reject and backwash, including GAC backwash, are recycled to head of plant and solids captured in the lime coagulation stage. Initial design was for 50 ML/d but some non-membrane items have been designed for upscale to 150 ML/d. An unusual fearure was char only one year on fro m commissioning Zenon offered a much improved membrane module, and Wacercare decided to purchase these and install them in the existing ranks. Zeno n cooperated by modifying dimensions to fie, but ancillary pipework and pumps had ro be upgraded. The whole project was completed without interrupting supply and was finished under budget and on time. Mal Peters, ofTenix Alliance, reported on the first UF plant in Australia to treat surface water, at Dainrree, north Queensland, to remove colour and Giardia, etc, from highly coloured rain forest water. The plant is unusual in rhac it operates on gravity head, but the steep terrain and unstable ground caused construction difficulties and they also had to overcome difficu lties with the effect of water hammer on the membranes. T he TOC turned out to be higher than anticipated, but chemicallyenhanced backwash of the Koch membranes is successful and rhe plant is reduci ng colour from 20 to 7 and UV disinfection is effective. Despite difficulties the plane came in well under budget. H elen Martyn of United Water Internacional, Adelaide, spoke on the project to partially desalinate the recycled water to be delivered to the North Adelaide Plains horticultural area. UWI, in conjunction with University of Adelaide, have compared a number of options. Desalination of the normal DAFF product water either by RO or EDR was compared to direct MF/RO or EDR treatment of the secondary effluent, prior to the stabilisation ponds. The estimates indicated that RO on the seco ndary effl uent was the cheapest and a pilot plant is bei ng commissioned along with trials of aquifer storage co balance winter/summer demand. Russell Taylor, of CSIRO, Melbourne, is exploring the option of using EDR for partially desalinating the effluent from Melbourne's Western Treatment Plane, from about 1000 mg/L to ca 500 mg/Lb.
EDR is a more robust process than RO, and th is may balance its slightly higher capex. Ir is nor so sensitive to silica bur colloidal marerials and heavy metal hydroxides can present problems. Laurence Pawlowski ar Deakin University, Geelong, is srndying the application of membrane processes to salt removal from dairy effluents. She has demo nstrated that Fe coagulation and centri fugation prior to MF pre-treatment, then RO , achieved ca 98% removal of solids and salts. However, the high suspended solids content of typical srreams required high energy consumption for the MF stage. T he possibili ty of using a desal ination plant as part of a novel water management scheme in Gippsland were outlined by Andrew Hodgki nson , and Ni ck Swain of Arup Water described three case srndies where RO is being applied in outback Australia, ie. the Yulara resort (where RO has just replaced an EDR plant which has operated smoothly for some 25 yea rs), Broken Hill and a small Aboriginal communi ty. The mai n problems are ensuring consistent power supply, main taining operator skills with tech nical support th rough releco m, disposal of cleaning chemicals, and in so me cases, disposal of the reject brine, though evaporation is no problem.
Health Aspects ln ano ther paper G reg Lesli e discussed the contrast between the strict guidelines covering re-use of treated wastewater and the lack of regulation of seawater desalination, which has assumed that seawater is safe... which is nor necessarily the case. However, an !DA committee has commenced reviewing this factor. For reclamation of wastewater for potable use it has become accepted that mul tiple barriers are viral, and th ey increasingly include the necessity to dea l with trace organics, such as foo d preserva tives and excreted pharmaceuticals, not to mention trade wastes. Santa Ana (CA) co mpared river water with secondary WWT and RO/ UV showing the last contained none of th e indicator organics cg NTA present in the others. However, modern analytical techn iques are capabl e of detecting nanogram concentrations. T o destroy these compounds advanced oxidation is necessary. UV by itself is not a barrier, bur when combined with peroxide may work, at a cost of an extra 3c/kL. However, the toxicology of the risk has not been ad equately demonstrated. Certai nly a cigarette, a beer and a hot dog exposes a hu man being to the equivalent of a lifeti me of drinking the product of a membran e trai n, such as N EWater. Regulations are necessa ry, bu t are always affected by public perception, so rhe education program installed at Singapore's NEWarer plant must be applied world-wide. Ian Law rook up this theme in his talk entitled "From Wind hoek to Singapore and Beyond ". O f necessity Wi ndhoek commenced direct recycling in 1968, using lime coagulation, ere. T hey now operate a 2 1ML/d MF plant recycli ng 25% of rhe supply. Th ere has been no increase in any chronic or acute disease in those 35 years. He discussed the stringent trials in Singapore, using both mice and fish and fo reshadowed on-line monitoring using biologically engineered fish , He concl uded wirh rhe ' Belagio Sraremenr on MBR rechnology' ... "Because membrane processes make sanitation, re-use and decentralisarion poss ible, water susrain abiliry can become an achi evable goal fo r the developed and developi ng worlds". Discussion following rhese papers focussed on ways of achieving berrer outreach to the public. Ken Ricketts of Freehills, Perth , gave an excellent review of the lega l and commercial issues to be deal t with when considering rhe insrallation of a desalination plant. (This paper is published separately in chis issue of Water) . The CD ROM ofthe conference contains the PowerPoint slides ofmost of the presentations, with all the technical details and graphics. It is available from bookshop@awa.asn.au
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water
MAY 200s 41
DESALINATION OPTIONS FOR SALINITY MANAGEMENT IN THE NORTHERN ADELAIDE PLAINS H Martyn, U Kaeding, C Heidenreich and Filtration (DAFF) plane, co produce recycled wastewater co an agreed standard for che VPS. Earl ier ch is year th e DAFF p lant also began to supply 3,400 homes at che nearby Mawson Lakes develop ment with recycled wastewater fo r toilet fl ush ing and garden irrigation.
Introduction One of Un ited Water l n ternational's (UWl ) priorities is co develop wastewater effl uent reuse schemes. However wastewater salinity is a major risk to the lo ngterm viab il ity of such schemes. T his project investigated che options fo r salinity reductio n and thei r economic im pacts on managing the effluent from the Bolivar Wastewater Treatment Plane (WWTP).
ASR trial site Bollvnr - --+-- - - - ''t-~ waatewater
Why the need for salinity management?
1-
b'ea tm e nt
Figure 2 shows the V PS demand fo r D AF F product fo r 20 01 co 2004, illustrating StV/ncont the wide variatio n in seasonal ADELAIDE demand. The monthly 0 5km T he Northern Adelaide Plains average fo r the past 4 years (NAP) contains the Virginia h as been increasi ng from 830 Triangle horticultural area, which Figure 1. Boliva r Wastewater Treatmen t Plant and Virg inia co I, 150 ML, however Pipeline . is an importa nt region for South seasonally chis can vary from Australia both agriculturally and a maxim um of nearly 2,00 0 economically. Over 6,000ha has ML/month (ca 66 ML/d) T he 150 MLD (550 GL/a) Bolivar been develo ped fo r irrigat ing crops, wh ich down to 130 ML/month (ca 4 ML/d). WWTP has been operated by UWI since total 12% of SA p rod uction. Before I 999, UWl are contracted co supply the VPS with I 996 and was upgraded in the lace 1990s to irrigation sup ply relied entirely upon effl uent not exceeding 1,5 00 mg/L Total meet the government's Environmental groundwater ext racted from two major Disso lved Solids (TDS) . With sewage I mptovement Programme (EIP) aquifers in che regio n. Over-extraction from sal inity ranging from 900 to 1,400 mg/L recommendations. Part of the programme these aquifers has led to a loweri ng of the TDS entering Bolivar and with evaporation involved the construction and groundwater level and infil tratio n of saline across 346ha of waste stabilisatio n ponds com missioning of a Dissolved Air Flo tat ion water. p la n t
Irrigation Water Resources in the Northern Adelaide Plains
RO treatment of secondary ejfiuent is the most cost effective of four scenarios. Maintain ing Virgin ia's high quality produ ce requires a reliable and low saline source of irrigation water fo r both the region's growth and survival. Therefore the SA Government initiated the Virginia Pipeline Scheme (VPS) to release pressure on NAP's natural water resources. The scheme was the first of its kind in SA and can su pply up to 20 GL/annum of reclaimed water to the irrigacors, th rough an extensive distribution network from the Bolivar WWTP (shown in Figure 1).
42 MAv 2005
water
1750
S° 1500
I
!. 1250
i
= ~
1000
0:
1
750
. ~
c!i 500
250
2001
2003
2002 a average
a max
2004
a min
Figure 2. Monthly Virginia Pipeline Scheme re-use volumes fo r 2001 - 2004.
(prior to the DAFF plant), this can be exceeded. Currently the only option available for managing the salinity levels is to dilute with potable water. In rhe summer months with the highest re-use demand chis ca n add an unwelcome demand on Adelaide's drinking water supply. A study of NAP soi ls by che PTRSA Rural Solu tion Focus Group identified salinity as a problem, which if left unmanaged would reduce crop yields. Kelly et al. (2001) scared che water supplied to the irrigato rs from Bolivar is moderately saline and may in crease soil sa lini ty. Figure 3 shows chat a majority of the crops grown at Virginia are already sensitive to the maximum salinity levels in the DAFF effluent. T his means char growers will use higher volumes of irrigation water to flush sales past the root zone with che consequence char high salinity water infilcraces the water cable. The use of higher than optimal salinity water will also reduce crop yields. Heidenreich (2005) calculated char salinity management has rhe porenrial ro reduce rhe sale load to the Virginia region by 50% at a rargec sal inity of 600mg/L, or 33% at a rargec salinity of 800 mg/L. Crop yields would increase, leadi ng to an estimated increase in fa rm gate value of $3 M and $2M pa for 600 and 800 mg/L sali nity irrigation water respectively.
produce a produce water of approximately 50 mg/L and 600 mg/ L TDS respectively and both technologies would require microfilcracion for pre-treatment. To obtain che req uired TDS concentration che desalted water wo uld be blended with the DAFF product. T he model was developed to ensure the desalted water concencracion was within 50 mg/L of the optimum T DS fo r 90% of the ri me.
How can UWI manage salinity?
The four scenarios for desalination
T he easy answer, if we wane to co ntinue the reuse of wastewater in the region, is desalination. T he difficult question is how to include desalination into rhe ex isting infras tructure at Boliva r fo r min imal cost, without co mpromising discharge co nsents and VPS demand. This was resolved by developing a model to answer a series of questions leading ro an optimum design scenario. ln the decision process UWI wished ro avoid: • Construction of an oversized new plant, meeti ng the VPS summer demand, bur being coo large for the winter demand; • Under utilisation of assets - both current assets and a furnre desalination planr; • Increased use of DAFF plant leading ro increased operational costs, on top of desalination operational costs; • Excessive volumes of desalination concen trace for disposal.
Two options for the feed water fo r desalination are availabl e at che Bolivar WWTP: • secondary effluent di rect from che activated sludge process, before the waste srab ilisacion ponds,
30.00 , - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2000
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25.00
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Figure 3. Virginia Ho rticultu re cro p production and tolerance to irrigation water salinity, at w hi ch no reduction in yield occ urs. • product from the DAFF plant. Figure 4 shows an overview of the Bolivar WWTP, showing che two options. Each of these cou ld be created by ei ther RO or EDR. T he use of either RO or EDR results in 15 to 25% (depending on che recovery rates) of the feed being wasted as conce ntrate to be di sposed of. Disposal of che co ncentrate can be a major cost issue co most desalinati on projects, bur forc unacely at che Bolivar sire a new seq uencing batch reactor, separate from the main plant, has just been commissioned to treat. high saline wastewater (approx imately 6,500 mg/ L TDS) from a separate Adelaide sewerage network. The RO concentrate for disposa l would be in che 5,500 ro 6,500 mg/L TDS
Rejec:110 Ocea11 0111/all ~ Dcsalinalion Oplion I or high .lll!i11it_r p/0111 ~-··············· ~ .......:
I
i
DAFF Plant
VPS Storage r---1~ Lagoon
Discharge to Gulfof St. Vincent Waste Stabilisation Ponds
Which TDS concentration?
T he impact of desalination on crop yield value was assessed and the conclusions gave two options fo r the optimum irrigation TDS concentrations as 600 and 800 mg/L (Heidenreich 2005). Reverse Osmosis (RO) and Eleccrodialysis Reversal (EDR) could
t
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Treatment Plant
Bolivar Sewerage Network
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Desalin at ion Option 2
1
't
Rejec/ lo Ocea11 0111/all or high sali11it_1· plwll
Figure 4. Bolivar WWTP.
water
MAY 200s 43
range and can therefore be disposed of to che SBR plant.
Blending with the DAFF product Figures 5 and 6 show the amount of DAFF product required to be blended with the either the RO or EDR scenarios to meet the present VPS demand, to attain T DS concentrations of 600 and 800 mg/L respectively. If DAFF product is used for both blending and desalination feed then the DAFF demand muse increase to compensate fo r the co ncentrate losses. This resul ts in increased costs in the operation of the DAFF plant th rough increased chemical dosi ng and power usage. Desalination of secondary effl uent would resul t in less use of DAFF product, with a subsequent decrease in operating coses. However, desalting secondary effluent by ED R would result in a product already at 600 mg/L so no DAFF product for a 600 mg/L VPS supply would be required and only a minimal amount for a 800 mg/L VPS supply, This would result in the DAFF plant, only commissioned in 1999, becoming obsolete, a factor that was not tenable.
l'ttsent
85
80
l)A f.'1-' f.DR 75
a DAPF
l>Cllall«I
80
8!i
• hll Ocn ltnl
2nd RO
85
80
2nd f,DR
"
80
.,
"
• DAPP Ulc11d
Figure 5. Volumes of DAFF product and seconda ry effluent required to meet VPS demand at 600 mg/L TDS.
16000
14000
.. 1,2000 ~
i ;
10000
DAFF Power costs
l
The nL1111ber of fil ters on line at the DAFF plant has a signi ficant impact on operating costs. At present the DAFF plant is operated in response to VPS demand , with some part of the day spent idle. The DAFF plant has 2 banks of 6 filters which can either operate independently or all together, dependent on the flow to the VPS , with any number of filters within a bank able to be operated at any one time. This results in a power usage graph as depicted in Figure 7. Increases in flow resul t in increased cost due to power usage, although chis may be offset somewhat if flow through che DAFF plant could be stabilised at a lower flow rather than peaki ng at extremely high flows to meet instantaneous demand. In order to obtain reasonable estimates of the power requirement, rhe data in Figure 7 was divided into three regimes: Demand < 20ML/d, 20ML/d < Demand < 45ML/d, and Demand > 45ML/d. Using linear regression within these three regimes resulted in rhe correlations shown. It has been assumed that the demand at which che second 6 filters are brought on-line is 45ML/d. These correlations were used to determine the power requirement for the DAFF plant as a function of DAFF demand. Given the variability in the daily DAFF demand for all scenarios investigated, the DAFF operating costs were calculated from che daily flow profiles.
1
44 MAY 200s water
J)AFF RO 75
;
8000
~
6000
~
:
4000
2000
Pres~ nl
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80
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80
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85
80
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"
.,
• DAFF OlcoJ
Figure 6. Vo lumes of DAFF product and secondary effluent required to meet VPS demand at 800 mg/L TDS.
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4000
2000
0 0
10
20
30
40
so
60
70
80
90
Plant Demand (MlJday)
Figure 7. Plot of the total power requirement as a function of dema nd for the DAFF plant for the period 1st July 2002 to 30th June 2003 . Also shown are the correlations to predict the total power requirement as a function of plant demand.
Membrane cost estimates Esti mates for rhe capital cost of integrated microfilrrarion (MF)/RO plan ts have been provided by Veolia Water Systems (VWS) while estimates of rhe cap ital and operating costs for EDR have been su pplied by Ionics Pry Ltd. Ir should be noted rhar rhe MF/RO data has been produced specifically for rhe feed water under consideration in this project an d does nor necessarily apply outside the scope of this project. T he mm-key cost for rhe project were broken down to include four major coses: core eq ui pment coses, add itional equipment coses, project delivery coses, and civi l construction. Power coses were calculated using the average power cost for the site of $0.0897/kW.h r. T he maintenance costs for an RO plant were based on data provided by VWS whi le chose for EDR were based on published literamre (U RS Australia 2002).
Ultimately, which is the most cost effective - RO versus EDR? The cost analysis results are shown in Table I. leading to the conclusio n that RO treatment of seco ndary effluen t is rhe most cost effective means of co ntrolling salinity on the NAP. These costs do not include overheads relating to project fi nanci ng and insurance. As a result of this analysis a research project has been established incorporating an M F/ RO pilot plant to investigate rhe treatment of rhe different wastewater treatment screams. This pilot plane data will allow furthe r optimisation of rhe model, by incorporating sitespecific data and memb rane fou ling tendencies. This work fo rms part of a 3year ARC-Linkage Project being undertaken by the University of Adelaide in collaboration with Uni ted Water Internacional, Veolia Water and RWE Thames Water. Another aspecr of rhe project involves a PhD student modelling rhe VPS distribution network to assess rhe operatio n and performance of the cu rrent pipeline infrastruccure and to determine the impact of desalced water on the network.
Table 1. Cost Ana lysis. Scenario 1 DAFF & RO
Scenario 2 DAFF & EDR
Scenario 3 2nd & RO
Scenario 4 2nd & EDR
23.86
36.58 4.09
26.03
39.60
3.93
3.31
3.33
0.35
0 .42
0.33
0.40
Capex ($M) Opex ($M) Unit Cast (c/kl)
References URS Austral ia (2002) Econom ic and Technical assessment of desalination technologies in Australia: With particular reference to National Action Plan Prioriry Regions.
Prepared for the Agriculture, Fisheries & Forestry - Australia.
.... '
Heidenreich, C. (2005) Desalination of Bolivar Wastewater Effiuent: Impact of desalination on irrigated crop yield value. lfl,'( lf Research
and Development Report. Kelly, J., van der Wielen, M. and Stevens, D. (200 I) Susrainable use of reclaimed water on the Northern Adelaide Plains. Grower Manual. PIRSA Rural Solutions.
o :: /
I '-
A World Leader in Desalination by Reverse Osmosis Australian Water Services can leverage Degremont's worldwide experience in brackish or sea water desalination. With more than thirty years experience and 250
developments in the construction and operation of large scale reverse osmosis and nanofiltration units, Degremont is the worldwide leader in Desalination. These processes are used on a wide range of water qualities and flows both for municipal and industrial clients. Australian Water Services also relies an proprietary technologies developed by Degremont to provide reuse of urban and industrial wastewater solutions. Clients can benefit from our extensive experience in providing wastewater reuse plants for various applications including: - agricultural and landscape irrigation - aquifer recharge - industrial and urban reuse Design, build, operate and maintain is our historical business.
The Authors Al l the authors work for United Water Internacional, Greenhill Road, Adelaide SA 5000. Helen Martyn is a Process Technical Adviser, Uwe Kaeding is Research and Development Manager and Craig Heidenreich is a Water Treatment Engineer. Email Helen.Marcyn@uwi.com.au
www.australianwaterservices.corn.au
water
MAY 2005
45
wetlands
Ill
RENOVATING A CONSTRUCTED WETLAND FOR INDUSTRIAL WASTEWATER TREATMENT G Allinson, A Watt, D Gervasi, B Mitchell Abstract
,,--.....
This paper repom the research leading to the re-establish ment of a wetland at MasrerFoods' facto ry in Ballarar, Victoria, designed to treat food processing effluen t but which had fa iled in the first two years of operation .
Introduction The MasrerFoods Australia/New Zealand Snackfood facto ry (hereafter, MasrerFoods) is siruared in rhe rural ciry of Ballarar, approximately 100 km west of Melbourne. MasrerFoods, like many regional enterprises, is a large consumer of potable water (averaging 165 ML per year ove r rh e last 7 years), and discharges nurrienr enriched, high salt wasrewarer to sewer, with further trearmenr carried o ur by Central Highlands Water. In an attempt to red uce costs (MasrerFoods is billed o n a simple formula incorporating volume, biological oxygen demand (BOD), and coral suspended solids (TSS) of rhe effl uent), and provide water for reuse o n their gardens and lawns, in 1998 a wetlands system was built, with water flowing through rhe wetlands before reuse or d ischarge to sewer. Functional wetlands will improve the quality of wastewater by significantly reducing BOD and TSS, thereby reducing cosr of treatment if disposed of to sewer, or providi ng irrigation if the discharged water is of suitabl e quality. The MasterFoods wetlands appeared to work well for the first year or so after being commissioned in 1998. H owever, by early 2000, there had been on-going problems with plant health leading to loss of emergent plants, and excessive algal blooms. Apart from creating an unpleasant smell o n occasions, impaired visual environment, and their impact on the general h ealth of the wetland, the algal blooms also increase the cost of wastewater disposal to sewer due to the increased TSS concentrations in the wastewater. Therefore, the company became concerned about the quantity and quality of water d ischarged into their wetland environment, the fa il ure of this con structed system to
46 MAY 200s
water
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~ Cell ~
~
SI
S2
Cell 4
C'ell 6
S3
S4
-
Cell 5 1
Discharge to sewer, or recycl ing
I
Figure 1. Schematic of MasterFoods wetlands. Shaded areas in Cell s 2,3 and 4 , represent the shallow sections of the wetlands. Those denoted B 1, B2 etc, represent the sections that we replanted in October 2003. S 1, S2, etc denotes the deeper sections of wetlands from w hich samples were taken for water quality analysis.
meet design criteria, and rhe medium rerm challenges of resto ring their fun ction. In mid 2000, M asterFoods approached Deaki n University to discuss ways to improve rhe condirion/healrh of rhe wetlands, and in 2001 two Honours
reductions respectively), bur there were notable increases in total n itrogen (TN) (38%), suspended solids (SS) (37%), pH (10%) and oxygen with retention time in rhe wetland' s cells. In effect, rhe algal blooms were making the water quality
The p roper functioning of a constructed wetland fo r water treatment relies on the interaction of three components: water quality, wetland design, and the wetland plants. projects were undertaken in an attempt to gath er more infor matio n about rhe chemical and biological interactions in the system. Broadly, we found chat the wetlands were only partially red ucing BOD and coral phosphorus (TP) (50% and 49%
worse. The system also contained high salt loads (up to 4000 mg/L, Archer 200 1, Sull ivan 2001). W ith this information in hand, we began rhe developmenr of renovation / red esign options for the wetlands.
refereed paper
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wetlands
Figure 2. Rehabilitation of Cell2. A before and after comparison of (a) the wetlands in September, 2002; and (b) in September 2004.
Study Approach The proper function ing of a constructed wetland, whether for water treatment or habit, relies on the interactio n of three components: water quality, wetland design, and the wetland plants. Our first step, therefore, was ro evaluate these three factors.
Water Quality An understanding o f current and historical water quality was needed ro assess the relationships between the rrearmenr plant operation, and the health and operational effectiveness of the wetlands p rior ro the commencement of this project. Historical water quality data was collared from a n umber of different sources, including consultants' and MasterFoods inhouse rep orts. Some of these sources reported only the water quality data without methodology, so there is limited information concerning how the samples were gathered and analysed. H owever, using these h istorical records, and our own analyses and in situ measurements, we can say that since 2000 the water quality in the MasterFoods wetlands has generally been quite poor. For instance, BOD concentrations have flu cmated over an extremely wide range, from a high of 1600 mg/L ro as low as 5 mg/L. Suspended solids concentrations have also fluctuated over a wide range, from less rhan 10 mg/L ro 285 mg/L. The pH levels in the wetlands sysrern have never been reco rded below 7.5. The higher pH levels may be part of rhe reason that submerged and fl oating macrophyte species have struggled ro grow in the MasterFoods wetlands, since at elevated pH the plants b ecome carbon limited because of the shift in the carbonate - bicarbonate carbon dioxide equilibria. An additional problem for the plants is shading caused by excessive biofilm/phytoplankron growth, which can redu ce photosynthesis ro such an
48 MAY 200s
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extent that the plants can not meet their biochemical needs. N utrient levels are not a major issue in rhe MasterFoods wetlands although char is not to suggest that MasterFoods does nor want to reduce nutrient inputs to the wetlands. The main ai m for MasrerFoods is to use the effluent from the wetlands ro irrigate rhe surrounding land, and the nu trient levels in the effl uent do nor inhibit the use of the efflu ent as irrigation water. T he high salt loading does, however. T otal dissolved solids concentrations have generally been around 2500 mg/L, although concentrations as high as 4250 mg/L have been recorded in the wetlands. T hese levels make use on mrf problematic. T he historical water quality data obta ined was based on infl uent and effluent water quality data only, and lacked information for the main treatment cells (Cells 2, 3 and 4), which limited our ability ro assess treatment performance. So, in Ap ril 2003 we collected our own data. In-situ measurements were taken from 4 different sires in cells 2 and 4 (Figure 1) using a Model 611 intelligent water quality analyser (YEO-KAL Electrical P ry. Ltd. Australia). The parameters measured were pH, dissolved oxygen (mg/L), dissolved oxygen (percent saturation), turbidity, temperature and salinity. Water samples were taken using a sampling stick and transferred inro sample containers supplied by the commercial laboratories that undertook the analysis. Unfortunately, when the samples were taken, it was apparent that no effluent had been flowing inro Cell 2 for a significant period of time. Afrer discussions with MasrerFoods staff, we concluded that the cell could have been 'off-line' for some months. In other words, in 2003 the water quality in Cell 4 was more the norm than Cell 2. In which case, it is fa ir to say that at that time these treatment cells were not
providing much treatment. For instance, whilst turbidity was reduced in Cell 4 (from 190 ro 19 NTU), and rhere was limited reduction of BOD (from >220 to 140 mg/L), there was no reduction in TSS, TN or TP (r 35, 4.5 and 0.2 mg/L, respectively). Of rhe orher parameters measured, there was some improvement in DO concentration (from 0.2 to r 2 mg/L), bur essen tially no change in pH (8.7), EC (r3900 ps/cm), salinity (r 2. 1 %0), sodium, potassium calcium or magnesium ion concentratio n (rl80, 70, 20 and 620 mg/L, respectively), rota! alkalinity (r 4750 mg/L) or carbo nate, bicarbonate, su lphate and chloride ions (r 650, 220, 65, and 230 mg/L, respectively).
Wetland Design The MasterFoods system has 6 cells (Figure 1). Cell 1 acts as a holding and distribution cell for wastewater disch arging from the factory's treatment plant. Cells 2, 3 and 4 are the main treatment cells, i. e. where nutrients are removed, organics converted ro inorganics etc. Cells 5 and 6 are hold ing ponds, where the effluent is held until it is reused or sent ro sewer. Qualitative analysis of the MasterFoods design involved comparing wetlands systems wi th similar characteristics ro rhose present ar MasterFoods i.e. similar co nfiguration, average flow rares, and areas in an attempt to determine whether the design is suited ro MasrerFoods Ballarat site. The MasterFoods wetlands system is a Free Water Surface (FWS) wetland of "pond and island" design. In orher words, the effluent flow is above ground, the treatment cells have alternating deep, open water "ponds," and shallow sections (the "islands") in which the plants are rooted in the sediment layer (Mitchell et al. 1998). Shallow planted sections as well as open water zones in the configuration have rhe ability to remove nutrients, especially n itrogen , from waste effluent better than
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wetlands surface flow werlands without the alternating shallow - deep sections (Hammer and Knight 1994). Inco rporation of deep zones in surface flow werlands can elimi nate the need for high aspect ratios by redistributing water at several points throughout a wetland cell ro red uce the possibility of short-circuiting char can occur in shallow flow systems. The deep zones effectively increase the ratio between actual and theoretical hydraulic residence time (HRT), which is more cost effective than construction of long, narrow werland cells (Hammer and Knight 1994) . Q uanti tative analysis was also used to check if the MasrerFoods werlands had been co rrecrly sized for the amo unt and quality of wastewater that it was expected to, and currenrly does, treat. Two methods were used: Kadlec and Knight's meth od (1996) and Reed's method (1995). Boch methods consider wetlands as attached growth biological reactors, and therefore use firstorder plug flow kinetic models as the basis for their performance equations. Fi rst order kinetics simply mea ns char the rate of removal of a pa rticular co mponent is direcrly proportional to the remaining co ncentration of the co mponent. The main difference between Reed's approach and chat of Kadlec and Knight is the basis fo r the rare co nstant. Reed's eq uations are volumetric and temperature dependent. l n simp ler terms, the calculations are based on the available volume of the werlands, and the average water temperature. Kadlec and Knight's equation is area dependent, so the rate consta nt is related on ly to the surface area of the werlands, and remperarure changes are considered significant only for nitrogen removal. Kadlec and Knight also include a mi nimum possible poll utant co ncentration in their equations, whereas Reed secs minimum poll utant concentrations to be used as checkpoints after calculations (M itchell et aL. 1998). Without going into great detail, the basic pa rameters used in both sizing methods were: average flow (Q) 300 1113 /d, werlands area 18,000 111 2 (total area of open water), and 11 ,800 111 2 (area of Cells 2, 3 and 4), average depth 0.6 m, porosity, i.e the space ava ilable for water to flow through the werlands, 0.75. We used the original design's influent and effluent targets fo r BOD, TSS, TN, T P and ammonia. We also used influent data representative of wastewater quality char had been discharged into the werlands system thro ughou t 2002/2003. For instance, we wanted a 96% reduction in current BOD (from 250 to I 0 mg/L), 95% reduction in TSS (from 200 ro l O mg/L), and co reduce TP from l 6 to 2 mg/L, TN from 33 to 2 mg/L.
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Table 1. Species planted in 1998. Common reed Marsh clubrush River clubrush Common spike rush Toil spike rush Tall sedge Finger rush Gentle rush Swamp stonecrop Water plantain Tall cutty grass Water ribbon
Phragmites australis Bolboschaenus medianus Schoenoplectus validus Eleocharis ocu/o Eleocharis sphacelata Carex appressa )uncus subsecundus )uncus amabilis Crassula helmsii Alisma plantago-aqualica Cyperus lucidus Triglochin procerum
Table 2. Species planted in 2000. Jointed twig rush Tall spike rush Gia nt rush Water plantain Tussock sedge Tassel sedge Water buttons Swamp stonecrop Common spike rush Pole rush Purple loosestrife Common nardoo
Our calculations show that the wetlands were, and are, correcrly sized, both when using the original design parameters and current water quality. T he theo retical retention rime (17.7 days) for each treatment cell is very close to the I 6 days estimated by MasterFoods based on the ri me it cakes to fi ll the cells co mpletely using normal operating fl ows, and well above the tim e required to remove BOD from the efflue nt. T he calculated areas req uired for denicrification and ammonia removal (5,7 17 and 15,667 111 2 respectively) are both well below the actual size of the MasterFoods system. T he total achi evable effluent concentrations for TP and SS are slighrly higher than the target values, bur this should not be problem as nutrients are not a major issue with the effluent, and if the SS co ncentrations co uld be lowered ro 23 mg/L, then satisfactory removal will have been achieved.
Wetlands Plants Twelve indigenous species of aquatic macrophytes were originally chosen for planting in and around the MasterFoods werlands (WATER ECOscience and AWT, I 998). These are shown in Table l. The 12 species were apparenrly chosen because they were native to Ballarac area (i.e. indigenous), known to have a role in wastewater treatment, relatively easy to propagate and, therefore, reasonably priced, relatively hardy, and relatively non-invasive. However, we have been unable to locate documentation concerning the original planting scheme, and establ ishment period. Plant establish ment is an integral part of successful constructed wetland functioning, and poor establishment may have been a factor in the deterioration of the wetlands plant health. For instance, we do not know how rhe water levels in the werlands were managed during establishment. In 2000, approximately 4000 additional plants were planted into the system (Table 2). Again, we do nor know how the water
Upright milfoil Blunt pondweed Shiny swamp-mat Streaked arrow grass Running marsh flower
Baumea articulata - 25% Eleocharis sphacelata - 12% )uncus ingens - 10% Alisma plantago ¡ aquatica Carex appressa Carex fasicularis Carex tereticaulis Cotula coronopifolia Crassula helmsii Eleocharis acuta )uncus pallidus Lythrum salicaria Marselia drummondi Myriophyllum crispatum Potamogeton ochrealus Se/Iorio radicans Triglochin stria/um Vallarsia reniformis
levels in rhe werlands were managed during establishment. However, in April 200 I , the water levels on the planting beds were approximately 500 mm , and by late 2002, there was on ly a very spa rse covering of macroph ytes in rhe werlan ds system (Figure 2(a)).
Masterfoods Wetlands Rehabilitation The first stage of our work concluded char rhe werlands design was, indeed, appropriate for the site, both for the anticipated and actual water quality. However, the aquatic macrophytes planted in rhe system have all struggled to survive, perhaps because of poor establishment practices, poor water quality and poor water level management. The next stage of rh is project was to determi ne appropriate aquatic plant species fo r the wetlands, present a renovation plan to Masterfoods, and then ground truth the plan by replanti ng Cell 2 of rhe system. After careful consi deration of the costbenefi ts of reconfig uring the werlands, we deci ded co keep the original design and confi guration , but reduce water levels in rhe shallow sections of the treatment cells sign ificanrly, and introduce plants able to rolerate rhe salinity levels of the effluent. The method used to select plant species was quire simple. First, a literature search was undertaken for native plants rhat would be able to tolerate the salini ty levels found in the werlands, i. e around 2.5%. T hen, the search was further refi ned by choosing only species that will also survive if water quality improves, and have performed well in constructed wetlands elsewhere. In chis way, we selected the species shown in Table 3. So me of these species had earlier been
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wetlands planted in the wetlands, but not thrived. One of our tasks, therefore, was to discuss with suppliers the conditions under which the stock had been grown, and then to select stock (phenotypes) that had been grown under less than ideal condi tions, and which might therefore be somewhat preconditioned to the water quali ty experienced in the MasrerFoods wetlands. In October 2003, we stopped the water entering Cell 2, and a draw down was carried out to reveal the planting beds. Our aim was to do chis just in time to begin planting as soon as our planes arrived, partly to maintain moistu re levels in the shallow sections of the wetlands (the planting beds), but also to minimise the impact of our work on rhe factory. Unfortunately, what we quickly discovered was char there was little soi l or organic matter present in beds 2 and 3. T opso il for these beds had to be purchased quickly, with some risk of importing disease or weeds, but without which the 11 ,000 plants (purchased from Planrwize Nursery, Mernda, Victoria} were not going to thri ve. The delay caused by our need to source topsoil did allow us to assess the beds further, and we decided char beds l and 4 did nor need to be replanted. We fo und chat bed 1 had a good coverage of Phragmites australis along each side, and a number of healthy Bolboschoenus fluviatilis througho ut the middle section of rhe bed. Bed 4 was lightly covered with a monoculture stand of Phragmites australis. Essentially, we thought that the macrophyres present on these two beds would regenerate into healthy stands if the beds were given a short period to dry out and then, when re-wetted, water levels were managed correctly. Having added topsoil to beds 2 and 3, levelled and watered the soil, we planted out the beds. Broadly, we planted Schoenoplectus validus, Baumea articulata, and Phragmites australis in strips across the beds, generally in that order relative to the direction of water flow. Bolboschoenus fluviatilis bulbs were planted irregularly in che beds, as th is particular plant species has the ability to spread very well. Plant Establishment Initially, our plan was to water the newly planted beds with freshwate r fo r a period of 6 - 8 months to allow establishment of the plants, before introducing Master Foods effluent. However, at the time of planting the Ballarat region was on Stage 3 water restrictions, so we used grey water imported from Central Highlands Water (pH 8.4, TDS 640 mg/L) for the fi rst few weeks, until the cost of carting the water became too much. At chis point (lace November
so
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Table 3. Salinity tolerant species selected. Jointed twig-rush
Baumeo articulata
Bolboschoenus fluviotilis Marsh club-rush Common spike rush Eleochoris acuto Phrogmites oustrolis River club-rush Schoenoplectus validus (now known as Schoenoplectus tobernaemontoni) Sharp club-rush Schoenaplectus pungens Water ribbon Triglochin procerum Common reed
2003), MasterFoods effluent was mixed with the grey water in an attempt to slowly acclimatise the plants to the increased salt levels in the trade waste effluent. When it was apparent that the MasterFoods effluent was not having an adverse effect on plant establishment, the effluen t was used to water the plant on a more regular basis with occasional add ition of grey water from Central Highlands Water. The MascerFoods effluent was the only source of water for irrigation from mid January 2004. In mid- January 2004, the water levels over the planting beds were sec at I 00-200 mm , and broadly remained at that level until September 2004, when levels were lowered to 50-1 00 mm to promote new growth. Monitoring Growth T he growth and survival of the newly planted plants had to be moni tored, to co nfirm that the species selected were adapting to the effluent quality and the beds were filling out to an appropriate plant density. Non-destructive monito ri ng methods, including monitoring plant shoot nu mbers and maximum plant heights, were adopted to monitor the growth and survival of the newly re-planted plants in the wetlands system, as destructive methods would have interfered with restoration of wetlands fu nction. A total of IO quad rats (1 m x I 111) were haphazardly placed in the beds, and shoot numbers of each plant located within the quadrats cou nted by hand, each week from Nov 11ch 2003 to Feb 20th 2004. T he maximum shoot height for each plant located within each quadrar was measured from the substrate to the tip of the stem from Nov 11th to April 8th 2004, i.e. the highest shoot for each plant usi ng a tape measure. Growth data from the quadrats were combined and averaged to produce graphs highlighting the increase of shoot numbers and maximum shoot height over the sampling period. Growth comparisons between planting beds 2 and 3 were made using a two tailed t-test, with significance determined to the P = 0.05 level (Fowler et a/2001) .
Between April and November 2004 the wetland planes experienced three diffe rent seasons (autumn , winter and spring) and associated climates. Water levels in cell 2 were kept at a depth between I 00 and 200 mm across the planti ng beds during autumn to optim ise growth cond itio ns for the plants. However, during winter the depths across the planting beds were increased to between 200 and 350 111111 . In early April 2004, when the sampling/monitoring concluded, the growth of Bolboschoenus fluviatilis, Schoenoplectus validus and Phragmites australis had scarred to slow, wh ile Baumea articulata still displayed a constant growth. By mid-April, 2004, the fi rst signs that the plants in cell 2 were starting to 'die back' were observed as the first hints of brown appeared. In early May 2004, the majority of plants in planting beds 1 and 4 had started to turn brown, and larger sections in planting beds 2 and 3 were beginning to brown as well. By mid-May, planting beds 1 and 4 were completely brown, while in planting beds 2 and 3 Baumea articulata appeared to be the only species not experiencing some for m of 'die back'. Indeed, this plant remained green th roughout winter, albeit with little apparent growth. Resul ts from the quantitative monitoring period co nfirmed visual imp ressions chat the replanting was successful, with good growth displayed by all species chat we planted, with few deaths in their first year of growth. Schoenoplectus validus displayed the best growth in terms of increasing shoot numbers, while Phragmites australis and Bolboschoenus fluviatilis displayed the best growth in terms of increased plant height. The statistical rests showed that there was no significant difference between the average maximum height increase per plant or average number of shoots in beds 2 and 3. Therefore, the fact that bed 3 seemed to be drier than bed 2 for much of the rime has not had an impact on plant growth. During sp ring 2004, the plants in cell 2 displayed good re-growth, with the majority of plants producing new shoots (Figure 2(6)). A rapid survey of water quali ty in each of the deeper sections in each treatment cell was conducted on September 25th 2004, using a Model 61 1 intell igent water quality analyser (YEO KAL Electrical Pry. Ltd. Australia) . T he survey showed that Cell 2 now has significantly higher dissolved oxygen (percent saturation) than cells 3 and 4 (~200% cf. 16-23% saturation at the outlet). That dissolved oxygen levels increase along cell 2 is suggestive of a better functio ning wetlands, with the macrophyre
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wetlands stands (and associated biolfilms) beginning w undertake treatment fun ctions not available in the macrophyte deprived cells 3 and 4.
Summary The proper functioning of a constructed wetland for water treatment relies on the interaction of rhree components: water qualiry, wetland design, and the wetland plants. Our evaluation of the MasterFoods wetlands suggested chat there was nothing wro ng with the design, but that current water quality exceeds many of the original design parameters. Plant estab lishment is an integral pa rt of successful wetland fun ctioning, and poor establishment may have been a facto r in the deterioration of th e original plants' health. Based on the success of our replanting efforts in Cell 2, we have now replanted the remaining treatment cells with species ch ar should be tolerant of Masterfoods' wastewater, but rhar should also thrive as Master Foods adopt policies and processes designed ro reduce the sali nity of their effluent. Finally, although our renovation has been slow by ind ustrial standards (~ 2.5 years), rh e stepwise process (assessment, options, renovations) has provided ample opportunity co educate MasrerFoods staff on the needs of their piece of ecological engineering, i.e. the wetlands, and such understanding and ownership of rh e system can only bode well for the future.
Acknowledgments This work is rhe result of a partnersh ip between MasterFoods and Deakin University, in which MasterFoods has provided fina ncial and on-ground support, and Deakin University technical expertise. The authors gracefu lly acknowledge the financial support provided by Masrerfoods, and in particular co AW in the form of a scho larship, and co-operation in publication of the results. We thank Mr Bruno Bomitali, Mr Lawrie Rieniets, and Mr N ick Rosendale for their help and assistance on sire. We also acknowledge that, in part, the project was supported by the Australian Research Council (Linkage Grant #LP0347630).
The Authors Graeme Allinson, Adam Watt, Dion Gervasi, Bradley Mitchell are all wirh rhe School of Ecology and Environment, Deakin University, PO Box 423, Warrnambool Vic 3280, graeme.all inson@deakin.edu.au.
References Archer R (200 1). The growth and survival of lemna minor, Azolla filiculoides and Wolffia
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ARTIFICIAL SUBSTRATES (AQUAMAT™) AND BIOFILM TREATMENT OF INDUSTRIAL WASTE WATERS IN CONSTRUCTED WETLANDS - THE MASTERFOODS EXAMPLE Dion Gervasi, Graeme Allin.son, Bradley Mitchell, Paul Jones, School ofEcology & Environment, D eakin University, Warrnam bool, Vic 3280
Constructed wetlands, such as the MasrerFoods wetlands, are being increasingly used for rhe secondary and tertiary treatment of industrial effluents high in organic carbon (BOD), TP, TN and T SS. A sign ificant advantage of constructed wetlands is their ability ro absorb and process pollu ta nt spikes. However, the typical response of constructed wetlands to sustained nutrient enrichment is algal blooms, poo r water quality and a loss of macrophytes. T he major fu nction of macrophyces in treatment wetlands is as substrate for the growth of the biofilms responsible for the major treatment processes in wetland systems. Once macrophytes have been lost from a wetland system the efficiency of the system has been compromised, and intervention is essential. The theory of alternative stable states says that at low nutrient levels (<0.05 mg/I P) shallow water bodies will be dominated by macrophytes and at high nutrient levels (>0 .15 mg/I P) the system will be dominated by algae, but at intermediate nutrient levels the system may exist in either state. Therefore, at intermediate nutrient levels it should be desirable ro develop management techniques which would induce a shift from an algal dominated wetland ro a clear water macrophyte dominated system. One way ro rhis may be ro introduce artificial structures covered with biofilm into the wetland, in essence compensati ng for the lost macrophyres, and hence lost biofilm. · AquamatTM is used in the aquaculture industry as substrates for biofilm production ro improve srock growth and yield, although secondary benefits fo r water quality improvement have been australiana in rhe consrrucred wetland of Mars Confecrionary, Ballarar. Deakin Universi ry School of Ecology & Environment Honours Thesis. Fowler J, Cohen L, Jarvis P (200 1) 'Practical Srarisrics fo r Field Biology' 2nd Edition Oohn Wiley and So ns: West Sussex) Hammer DA, Knight RL ( 1994) Designing consrrucred wetlands for nitrogen removal. Warer Science and T echnology 29, 15-27. Kadlec RH, Knight RL ( I 996). Trearmenr Wetlands. C RC Press, Inc.: Boca Raron. Mitchell C, Wiese R, Young R (1998). Design of Wastewarer Wetlands. In 'The
achieved. However, until now, the use of biofilm covered Aquamat™ for water quality improvement in an industrial treatment wetland has not been explored. Part of our research in the MasrerFoods wetlands is whether the use of Aquamat™ as artificial biofilm substrates will: 1) Support significant biomasses of biofilms and provide short-term water quality imp rovement. 2) Provide sufficient fo rce to induce a shift from an algal dominated wetland back to a clear water macrophyte dominated wetland as srated by the rheory of alternative stable states. A pilot study in a series of replicated flow-through rank systems built between cells 4 and 5 of the masterFoods wetlands, determined that Aquamats could support the development of biofilms in MasterFoods effluent, but did not reduce phyroplankro n levels. However, ro uti ne monitoring ind icated rhat DO levels in the influent water were low, and may have been limiting biofi lm growth. A further trial was cond ucted with added aeration to improve DO levels. Preliminary results indicate that under the current MasterFoods conditions, the use of Aquamar™ and aeration has a beneficial impact on water quality by reducing phytoplankton development, at least in the short term. Research is ongoing and we intend to explore the relationships and interactions of the higher trophic levels, e.g zooplankron, in tl1e application of chis technology within the bounds of the theory of alternative stable states. T his aspect of our project is supported by MasrerFoods d1rough the Australian Research Council Linkage Grant Scheme (LP0347630). C onstructed Wetlands Manual'. Eds R Young, G White, M Brown , J Burton and B Arkins. Depamnent of Land and Warer Conservation. N.S.W: Sydney. Reed SC, C rires RW, Middlebrooks EJ ( 1995) 'Natural Sysrems for Waste Managemen t and Trearmcnr 2nd Edition . (McGraw H ill) . Sullivan C (200 I) Management of Algal bloo ms in wetlands used for industrial wastewater trearme nr. Deakin University School of Ecology & Environment H onours Thesis. WATER ECOscicnce Pry Lrd and Australian Warer Technology Pry Led (1998). Mars Confectionary Constructed Wetland, Draft.
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TRAINING FOR WETLANDS IN NSW AND VICTORIA N Ashford, J Horsfield Abstract T his paper summarises a research project funded by ANT A (Australian National Training Authority), sponsored chrough the Board of Vocational Education and Train ing, to investigate skilleco syscems of constructed wetlands technology, the use of constructed wetlands for sustainable water management and the potential role ofTAFE as an "innovation agen t" to promote and p rovide training in constructed wetlands technology. A variety of research methodologies were used to canvas views from a spectrum of stakeholders. Four reports were prepared. This paper outlines some findings of the reports wich a focus on stormwaterconscrucced wetlands.
The investigation of constructed wetlands was undertaken through a variety of mechanisms: • Review of the Ii terature, texts and reports • Internet searches • Online discussions within a N ews Group of industry proponents • Personal interviews
Why TAFE Involvement in the Constructed Wetlands Industry? T he National Environment Centre, NSW TAFE Riverina Institute, Thurgoona Cam pus, was part of a National Traini ng Authority (ANTA) project investigating changes in work and skills as key compon ents of eco no mic and regional d evelopment ini tiatives. T he NSW Department of Education and Training fu nded several projects to investigate skillecosystems as a new and d ynamic fram ework for responding to these changes. In the case of the National Environ ment Centre Project, the Sustainable Water Management Project, Constructed Wetlands was designed to identify and develop the role of Vocational Education and Training (VET) providers withi n the skill ecosystems relating to const ructed wetlands.
Skill ecosystems are interdependent clusters ofskills located within regions and industries which are shaped by factors such as the nature and configuration offirms, the characteristics ofproducts and services, market dynamics and regulations and key institutional and policy settings (ANTA, 2004)
Research Methodology The aim of th e research was to investigate: • What was happening with constructed wetlands?
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wetlands for stormwater have been a requirement imposed as part of development approval (eg Wagga Wagga and Melbourne).
Traditional Cost Benefit Analysis Interviews and discussions with a wide spectrum of contribu tors to the Project indicate that formal Cost Benefit Analysis (CBA) is generally not undertaken in the d ecisio n-maki ng process when considering a constructed wetland fo r a particular site. R esponses from various professionals
The availability for training for the on-ground labour force is limited, as is general information sessions for community groups. • Field trips to local constructed wetlands
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52 MAY 200s
• What opportun ities exist for developmen t of training by TAFE in constructed wetland technology?
• Telephone discussions. T he research focused on southern NSW and Northern Victoria. The 'News Gro up' was established comp rising personnel in research, private industry, local government, education and service instrumentalities. In-put was also sought fro m major water and environmental authorities in Sydney and Melbourn e. The membership was largely focused within the stormwater sector, as they are the most visible and commonly installed wetlands in southeast Australia. T he fi ndings of the project were presented within four reports: • Cost Benefit Analysis • Market Place Evolution • Markee Place Awareness • Skills Demand for Training.
Cost Benefit Analysis Report Findings Why Construct a Wetland? Generally builders of constructed wetlands want a wetland for a number of specific reasons. Historically, the impetus fo r wetland choice has been based on a desire for more nacural solutio ns to control pollution, nutrient and sediment loads, the perceived long term low maintenance costs, altruism by some and potential for increased land values by others. Recently stormwater has b een viewed as an asset rather than a liability and const ructed
convey the dilemma that in carrying out cost-benefits analysis of constructed wetlands and any alternatives it was difficult to include social and environm en tal/ ecological costs an d benefits. T he actual work that a constructed wetland performs in che manner of retarding, storing and treating water can be compared in relation to land, fi nance, ap provals and time required for construction. When the additional "benefits" that are attributed to constructed wetlands are to be valued, C BA beco mes very subjective and relates to the environmental ethos held by the assessor. CBA also fai ls to include p ublic participation. At an informal level listing the perceived benefits and functio ns of constructed wetlands is a useful 'selling poin t' cool with the community. The recognition char fi nancial, ecological and social dimensions need to be inco rporated in d evelopment proposal assessment has led to the use of more comp rehensive costing tech niques viz: Life Cycle Costing (LCC) and T riple Bottom Line Assessment (TBLA).
Life Cycle Costing and Triple Bottom Line Assessment Life Cycle Costing is a management cool or process char examines the whole life of a system; from the rime the resources are removed from the gcound to the time they are returned to the ground at rhe end of the systems' life. This process is commonly known as "from the cradle co
wetlands rhe grave" analysis. T he CRC fo r Carchmenr Hydrology has developed darareco rd ing sheers ro assist storm water managem enc agencies with LCA. (Taylor, 2003) . The Triple Bottom Line focuses corporations not jusr on rhe eco nomic value chey add, but also rhe environmental and social value they conrribure and /or destroy (Taylor & Fletcher, 2004). Ir places an onus on companies ro consider ch e moral and ethical consequences of rheir decisions. T he C RC for Carchment Hydrology is currently developing guidelines ro enab le use of T BL assessment fo r proposed urban srormwarer measures. T he guidelines will facilitate decision-making based on fi nancial, social and ecological co nsiderations (Taylor & Fletcher, 2004). The guidelines have been developed fo r rhe Australian urban srormwacer management context, where historically a few technical experts made decisions, wirh limited refe rence ro rhe co ncepts of rocal quality management. The new guidelines are supported by the inclusion of a lifecycle costing component in MUSIC (Model for Urban Stormwacer Improvement Conceptualisation - th e C RC's Modelling program fo r srormwacer managers). MUSIC is a design rool char estimates both srormwarer poll utant generation and the perfo rmance of sro rmwa rer rrearment measures. Jr supports decision-making and enab les users to evaluate co nceptual designs and ro demonstrate the perfo rmance of particular des igns. Melbourn e Water uses MUSIC to assess the impacts of proposed developm ent against perfo rmance rargers (Lloyd, Wong & C hesterfield, 2002). Ocher modelling rools are also available.
Market Place Evolution And Market Place Awareness Report Findings While there has always been a maverick element in society char championed rhe cause of th e environment, ir was not un til rhe I % O's and 1970's char the negative impacts of human development on the enviro nment were considered as significa nt
enough ro warrant changes in development practices. In recent years, changing weather patterns and altered flow regim es have fo rced our communi ty ro consider and adopt water management practices rhar are sustainable and conservative. National Context
Policy The role of che Federal Government wirh irs overarching policy directions has acknowledged che need fo r adoption of sustainable water management practices wirh the development of such documents as the Brun rland Report, 'Our Co mm on Future 1987', 'National Strategy fo r Ecologically Susta inable Development' (NSED, 1992) and 'Sustainable Develop ment in Austral ia' (August 2002). Chapter 28 of 'Agenda 2 1' calls fo r local government aurhoricies (LGA's) ro develop and implement their own 'Local Age nda 2 1' (LA2 l) plans. (These are generally supported by smaller LGAs bur are completed by larger, berrer resourced LGAs). 'COAG', ' Environmental Task G roups', and various incernarional agreements such as T he 1992 Rio Earth Summits Agenda 21' and ' Kyoro', guide the Nation's policy making. Funding ro che States, while politically linked, can also encourage compliance with Federal policy. The cu rrent Australian Water Industry Road-mapping Project is co provid e advice and sup port ro the environmental sector in implementing rhe Federal Government's enviro nmental initiatives. Th is Project seeks ro establish an industry vision supported by strategies with clearly identified tasks, rimeframes and recommended responsibilities ro address technological, institutional supply and social challenges. le encompasses che breadth of warer issues incl uding delivery, security, trading supply and rreacmenr across Australia. Comments on D raft 1 were concl uded in September 2004 and the final report was due in February 2005.
Research and Technology Histo rically, the Federal Gove rnment has played a majo r role in providing
funding for scientific research across a broad range of areas. During che lace eighties and nineties conscrucred wetl ands were seen as a viable ' natural' solution co some warer industry problems. Cooperative Research Centres (C RC's) were responsibl e for much research and participated in confe rences char co nsidered che role of constructed wetlands within the sro rmwacer and wastewater contexts. The then C RC for Wastewater and Pollution Co ntrol focused on constructed weclands and developed modelling softwa re (SWAM P) ro aid design and sizing of constructed wecl ands. The C RC's fo r Fresh Water Ecology and Catchment Hyd rology (CRC-CH) currencly run programs ro increase understanding of wecland processes. C RC-C H's foc us on srormwacer weclands and water sensitive urban design (WSUD) occurs within a catchment contex t. During 2006-7 fundi ng cycles these C RC's will operate as eWacer C RC. A number of university's engineering and environmental departments include urban storm water, wecl ands, constructed weclands, and wasrewarer invesrigacions as part of rheir resea rch focus and some of these are linked co C RC's. fndu scry associations and bodi es may also administer funds and grants co furth er knowledge in rhese areas by parciciparion in con fe rences, traini ng evencs, reports and special projects. Research within rhe pri vate sector provides rhe opportunity ro expl ore new ides, adapt existing technology and refine or imp rove previously trialled ideas. State Context
Policy Ac a Scace level many Aces of Parl iamenc can affect rhe assessment of constructed wetlands developments. Generally, local office rs administer rhese aces ac a regional level. Regulatory aurhoriries and agencies develop and administer policy and/or legislarion, while devolving implementation ro local government. They sec a framework and direction in which
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wetlands local agen cies operate and develop . The authorities rend ro manage rhe growth , acceptance and pro motion of new ideas and technologies coo. ldeas and changes are often presented as "best management practice", included in draft guidelines and lacer included in legislatio n (eg nutrient load targets co waterways, op en space percentages within new develop ments) or as policies (eg reduce erosion and sedimentation, public co nsultation p ractices) . For example, durin g the lace 1990s- early 200 0s in New South Wales and Vicroria ir became a requirement fo r Local Government Authorities (LG As) ro develop Sro rmwarer Ma nagement Plans with some fu nd ing being p rovided and specifi c requiremen ts ident ified u nder special program s such as the Coun try T owns Water Supply and Sewerage P rogram.
Colla boration Co llaboration between scare agencies, lead ing stare water authorities and municipal associatio ns, has resulted in partnerships fo r rhe development of ideas that faci litate local government co mpliance wirh Srare legislation and policy. Conscruccecl wetlands are recognised as multi-ap plication technology and their evolu tion has occu rred within a number of contexts ar rhe Stare level. T he goal of enhan ci ng water-way values has resulted in a fo cus ro improve the quality of rhe drainage water en tering receiving waters. T he EPA in NSW is currently undertaking a review of rhe Srormwarer Management Guidelines originally released in 1994. The new documents will add ress issues arising from 20 years o f experience and include up-ro-dare info rmatio n on srormwarer technologies, including const ructed wetlands.
Constructed W e tlands and the W ater Sens itive Urban Desig n Perspective Water Sensitive U rban Design (WSUD), a methodology for the integration of urban water cycle managemen t within urban planni ng is rhe forma lisation and upgrading of new and old tech nologies. Constructed wetlands have b ecome a recognised component of WS UD rather than a single foc us technology withi n the srormwarer industry. Both NSW and Vic released CDs in 2004, ro encourage best managem ent practice and a consistent and standard approach ro the design of WS UD elements. The production and dissemi nation o f CD's allows this information co be readily available ro local government authorities and developers.
54 MAY 200s water
T here is in fo rmation exchange co regional areas through professional association capacity build ing, sho re courses, sem inars, workshops, rou rs and printed materials and chis h as been limited in ma ny cases co pro fess io nals in larger local and state government authorit ies . I nformation does nor always reach practi tioners in small and isolated councils and enterprises particularly in ru ral and regional areas. Merro-cen rriciry of fu nd s, perceived concen tration of departm ental interest in metro centres and parochial attitudes in regional areas m ay further exacerbate the difficul t ci rcu mstances for in for m ation transfer (research suggests rhar there is a rime lag of 3-5 years fo r in celleccual transfer and practice fro m m etropo litan ro rural areas) . P rofessional associations and conferences assist ro alleviate these di fficult ies co a d egree bu t tra nsfer of knowledge co non-attend ing colleagues becomes critical. D isinterest, co nservatism and lack of enthusiasm withi n an organisation can erode the drive ro im plement change and the status q uo therefore remai ns. Regional and Local Context
T he local offices of State Au th orities su ch as E PA, DIPNR (NSW), ONRE (Vic) as well as Catchmen t Management Au thorities (CMAs) play a vi cal role in che implementatio n of both Federal Government di rections and Stare legislation. The CMAs assist in fac ilitating a consistent catchm ent-based approach ro develop men t, and encourage di ffe rent local governmen t areas w ithin catch ments ro adop t a bro ad catchment view when determini ng development approvals. I n Victoria, new developm ent applicatio ns are frequently referred ro CMAs for co m m ent as part of the approvals process . Policies within part icu lar catchm ents may influence the num ber of wetlands developed. Local Govern ment is responsible fo r tran slating Stare legislation ro fir the local context by development of council policy docu ments and plan ning schemes Local government is co nstrained by a rare based budget and burdened by aging in frastructure which may delay immediate implementation of 'new' regulations. Individ ual Cou ncil officers interpret and apply bylaws, guideli nes, policies and legislation. T his can be a subjective process. Local government authorities embrace new policy d irections as requ ired bu t they do nor always have the necessary exper tise and experience ro ensure successful outcomes. So me o f th e early constructed wetlands testify ro chis. Local office rs and Councils are at tim es wary of
accepting respo nsibility fo r technology without evidence of potential success. Cautio n is justifi ed given the inherent variabil ity of con scrucced wetlands, constraint of funds fo r main tenance and operatio n and rh e long term , un kn own legacy.
Findings From Skills Demand for Training Report Within rhe limits of ch is research no professional fu ll-time, long-term specific constructed wetland course was identified . H owever, there are many opportunities available fo r im proving skills with in the water industry: short courses, seminars, professional train ing days, short tours, workshops, ta ilored training by consul rants, in-h ouse staff training, conferences, in fo rmation sessions ere have been run in rhe past and conti nue ro be offered by educatio nal inscicucions, professional associations, p rivate consultants, government departments, . . com mumry groups, quasi-government insrrumencali cies and local governmen t authori ties . For example: Greening Austral ia, in V icroria, has run a 5 day wo rkshop on Wetlands. Over time ir increased its content o n con structed wetlands. Shorr cou rses and sem inars are run by che Shorclands Wetland Centre at and by the Sydney Olymp ic Park Wetland Educational and Traini ng unit. T he CS lRO has also extended its train ing online train ing prog ram beyo nd AUSRJVAS assessment procedure, ro include ocher facets o f water ecology and m anagement. I n m ost cases the target group for training is graduate professionals interested in extension of their existing skills base.
The availability for training for the on-ground labour force is limited, as is general information sessions for community groups. T he areas suggested as potential trai ning opportunities for TAFE depended largely o n experience and area o f interest of the interviewee. These are sum marised below: â&#x20AC;˘ Developers: Some property developers need assistance with development design . â&#x20AC;˘ Commu nity Residents living in developments with water fea tures need help with understanding che environmental impact of their actio ns, (eg fertilising the lawn may result in run-off rhar causes water po llution) and wetland ecology and functio n (eg 'We cannot see rhe water, pull our che planes', 'algae grows').
wetlands • Developments with grey water recycli ng systems. Residents with grey water recycling systems require training to maximise the potential and live within the limitations of their recycl ing systems. • Landscape Architects. An understa nding of wetland ecology and plant requirements co uld assist landscape architects to produce '.andscape designs where fun ctionality and aesthetic pri nci ples were co mbi ned. • Local Govern ment Maintenance staff in new housing developments may "inherit" a wetland as part of their job. An understanding of co nstructed wetland fu nction and eco logy co uld improve performance and reduce problems such as mosq uitos, alga blooms and poorly perfo rming Gross Pollutant T raps (G PT s) • Farm Dams: Many farmers with dams have approached consul tants at trai ning sess ions seeking additional wetland information. • Co nstruction Contractors. Often the construction crews did not understand what they were doing or why and the resulting co nstructed wetland reflected this. An understanding and appreciation of the need for "soft" machinery work, for th e accurate fo llowing of designs and precision work would increase a werland's potential fo r effective water qualiry improvement. • The trai ning of local government health officers or accredited/licensed professionals to inspect and/or advise on and/or maintain alternative grey water systems, reed beds, on site waste systems, third pipe systems and d ry toilets would help maintain alternative technologies in working order. In Victoria th e Pl umbers "Reused Water" Green Card program addresses some of
these issues, bu t such skilled plumbers are rare in most rural and regional areas. • Inclusion within the Waste Water Ind ustry Certificate streams of new competencies chat focus on co nstructed wetlands ecology, maintenance and monitoring as pare of Sewerage Treatment Plan c operations cou ld assist operato rs assimilate new technologies successfully.
Conclusion Constructed wetlands are increasingly feam red in new and upgraded water management systems. T he outcomes fo r all stakeholders could be improved through the development of accred ited train ing. The chall enge is fo r all trainers to work together for the common good of sustainable environmental management. The mandate fo r TAFE is accred ited training, as it implements Federal Government policy to up-ski ll the Austral ian Workforce. Pose-graduate professional training is freq uently managed th rough universities bur training needs identified at rhe certificate and diploma level offer an opportunity fo r the development of training by TAFE.
Acknowledgments The Project ream ack nowledges the inpu t and generosity of the many practitioners involved with co nstructed wetland technologies who gave their rime and shared experiences.
The Authors Narelle Ashford is Project Manage r and Janice Horsfield is a Principal Researcher at the National Environment Centre, NSW
TAFE Riverina lnscimce, PO Box 827, Albury NSW 2640, narelle.ashford@TAFENSW.ed u.au
References ANTA (2004), ANTA Nat ional Skillecosystem Proj ect. The Role of VET Providers in Delivering Improved Outcomes Across Ski ll Networks. NSW Depamnenr of Education and Training and ANTA. Unpublished Progress Report. D epartment of Land and Water Conservat ion New South Wales (1998). The Constructed Wetlands Manual Volumes I and 2 (H0/61/97) Hunter, G. & Fisher, P. (undated paper) Li fe Cycle Assessment vs Cost Benefit Analysis "Fu nding Pollution Concrols For Environ mental benefits" (copy supplied by Hunter) Lloyd, S., Wong, T ., Chesterfield, C., (2002) Water Sensitive Urban Design - A Srormwater Management Perspective. Cooperative Research Centre for Catchment Hydrology. Industry Report 02/ 10 Melbourne Water (2004) Water Sensitive Urban D esign WSUD Engineering Procedures Srormwater. C learwater Inform ation Exchange & Melbourne Water. Draft CD Taylor A and Fletcher, T., (2004), T riple Bonom-Line Assessment of Proposed Urban Srorrnwater Measures co I mp rove Waterway H ealth (personal communication/u npublished paper) Taylor A (2003), An lnrroducrion to Life Cycle Costing Involving Structu ral srorm water quality Management Measures, CRC Catch m ent H ydrology !available from ,vww. toolki t. net.au products > music> publications] Water Sensitive Urban Design in the Sydney Region (2004). NSW Partners Sydney Coastal Cou ncils, Advocat ing for the People of Western Sydney, Upper Parramarra River Catchment Trust, S rormwater Trust. CD
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RISK MANAGEMENT AND DUE DILIGENCE IN THE WATER INDUSTRY A Davison, D Deere Common Law
Abstract Utilities run businesses supplying products and services includi ng drinking water, sewage services and stormwater services. Managing these businesses requires a knowledge of and co mpliance with the jurisdiction in which the utilities operate. In this paper, we consider how having comprehensive and defensible risk management systems in p lace can help demonstrate chat a utility is conducting its business in a duly diligent fashion.
Introduction For utilities to be run as viable businesses, they need to be cognisant of their obligations under the legal framewo rk in which they operate. Understanding a utility's obligat ions forms part of its d ue d iligence and consequently, there is a general obligation to identify, assess and manage its risks in a wider operational context. In this paper, we will outline the legal framewo rk, discuss due diligence and show how established management systems can facilitate demonstration of due diligence.
The Legal Framework in Australia In Australia, the legal framework is derived from English common law. Common law primarily relies on case history, which is known as precedent. Common law jurisdictions are also increasingly developing a body of statute law or codified law. An overview of the types of law and legal and health liabilities associated with the types of water products that utilities m ight provide is given in Table 1. It is important to understand the differences between the bodies of law as terms such as "duty of care" as applied to water utilities and managers will be different depending on whether they are captured in precedent or in statute. This paper was presented in its initial form ar the AWA's Victoria n Bran ch 2004 Regional Conference in Beechwonh, and expands on the concepts put forward by Davison et al (2004).
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Co mmon law is: • D er ived from precedent established by court judgements; • Traditionally associated with private property righ ts; and • Has arisen as a result of civil (as opposed to crim inal) actions. Justice in these actions is generally sought in the form of damages e.g. a monetary redress. Common law has historically had two main fu nctions: • To enforce the right to exclude others from the benefit or use of private property; and • To prevent the use of private property by one owner from having a detrimental impact on the ability of neighbouring private property owners to use their property. To protect these rights, the courts developed the laws of trespass, nuisance and negligence. Each of these elements forms part of the law of tons ("wro ngs").
Statutory Law
community consu ltation processes to help set the parameters of some of the riskier aspects of water utility busi ness (H url imann and Mackay, 20 04). This ap proach to developing gu idelin es and regulatio ns could also b e applied to the internal management systems of ucilicies.
Due Diligence Depending on the jurisdiction, due diligence can be an important defen ce for persons charged with an offence. H owever, in Australia, due diligence is only available where expressly provided for under srarnte. A defence of honest and reasonable mistake of face is available at common law. T he difference between the cwo defences being described as follows: • 'Due diligence' - requires proof of an absen ce of negligence or fault; and • 'Honest and reasonable mistake of face' involves an absence of a guilty m ind but not necessa rily an absence of faul t o r negligence.5 In law, d ue dil igence can be further described as:
• Often includes a codification of common law.
" ... rhe converse of negligence and negligence connotes a reprehensible state of mind - lack of care for the consequences of his physical aces on the pare of a person doing chem ."6
When supplying goods and services, it is the responsibility of a water utility to make sure that it complies with the relevant
There is a paucity of legal guidance on what constitutes due diligence. However, the focussi ng issue appears co be whether
Statute law is: • Law made by governments; and
"Due diligence ... depends on the circumstances of the case, but contemplates a mind concentrated on the likely risks [emphasis added]. " legislation and accompanying regulations. Uti lities also have a responsibility to customers in understanding the good or service being provided (i.e. treated effluent, potable water) and what it can be used for. Within the legal profession in Australia there are also calls for measures that build knowledge and trust in water utilities. Ir is argued that community trust in water authorities can be fostered by having
the defendant has taken all d ue care to ensure compliance with the legislation and che reasonableness test i.e. if a reasonable person would have taken precautions which the defen dant fa iled to take, then the defendant cannot claim to have been duly diligent (Lipman, 20 02). W hat constitutes the standard of care that a 'reasonab le man' would exercise is guided by:
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business Table 1. Example overview of legal and health liabilities associated w ith water products (presented in Davison et al, 2004 and developed from Moore, 2003 and Davison, Davis and Deere, 1999). Area
Sub-component
Specifics
Common low liobility in tort
Negligence
Negligent liability could be incurred in relation ta harm caused to: • Human health; • Property; or • Livestock health as a result of a utility supplying reclaimed water. Each of the elements of common law negligence still has to be proved (on the balance of probabilities). Duty of care is a key aspect of negligence. Far instance, a utility may hove a duty of care not o nly to those it supplies reclaimed water to but olso o wider group which could include: • Neighbouring landowners; ond • Those who hove access to land irrigated w ith recla imed water o r even those who hove gained access to the land without permission. Duty of care w ill be determined on a case by case basis but for the utility, the standard of that duty is likely to involve a risk-based approach including: • Understanding the system it is operating; • Understanding the inherent risks in that system; a nd • The ta king of reasonable steps to manage those risks.
Nuisance
Nuisance liability may arise where a neighbouring landowner' s land is affected by: • Pollution of sa il from the application of reclaimed water; and/or • Pollution of water from the application of reclaimed water. In general, liability rests with the person fr om which the nuisance emanates although liability may also be incurred by a party on land under the occupation and control of another.
Trespass
Trespass involves the interference with a property owner' s right to exclusive use of thei r property. A utility may face claims of trespass in relation to sewer overflows, odour issues and other impacts on neighbours (Slaughter and Farlegih, 2003) .
Misfeasance in public office
Utilities are often public bodies. Where public officers intentionally misuse their powers, an action of tartious misfeasance in public office can be bought. Public officers need to ensure the required power to exercise thei r authority and that they undertake thei r duties diligently.
Contractual terms
Utilities enter into contracts w ith customers. Breach of contractual terms relating to the quality and quanti ty of a water product is likely to constitute an area of liabil ity for the utility. It is important to expressly state what is and is not covered in any contractual agreement w ith the user of the water subject to lair trad ing provisions (Telford , 1999).
Contract liabi lity
False A utility must be aware that it is an offence under fair trading provisions to falsely represent that goods are of a representation of particular standard, quality o r composition 1• It is possible that the user of a water product will ask for a guarantee of goods or services quality from the utility as part of its ow n quality assurance program. In Australia, simi la r elements apply to " fit for purpose" requi rements under the defective goods provision of the TPA whic h is a form of statutory protection of Defective goods customer contracts 2 . Statutory liability
Breach of statutory obligations
The uti lity and user of the water will have to ensure cognisance of and co mpliance with obligatio ns in relation to health and the env iro nment and their associated regulations and guidelines . O ften, statutes provide persons with standing 3 that they would not otherwise be entitled to under common law, and hence can widen the circumstances under which a uti lity may face legal proceedings.
Statutory incorporation of guidelines
Many of the metropolitan water utilities in Australian, including Sydney, Melbourne and Perth, have licences that tie them to guidelines (subsequently NHMRC/ ARMCANZ, 1996 and now NHMRC/ NRMMC, 2004) that were designed to be of a voluntary non-legal nature (McKay and Moller, 2000). In this case, failure to meet these guidelines may bring with i t statutory liabilities.
Statuto ry immunity
Legislation under which water authorities ore constituted a nd their functions defin ed may also provide for circumstances in which the authority has been granted an exclusion of liability. However, the Australian High Court4 has narrowly read these provisions such that they do not extend to the normal commercial functions of the Authority, but only to the exerc ise of the specific functions or powers authorised by the legislation (Bartley, undated). Government utilities subject to corporatisation and privatisation are increasingly being treated by Australian courts as like private entities, especia lly w here they co nduct business activities also conducted by the private sector.
" .. . rhe sra ndard that is consistent w it h the diligence of a reasonable profess io na l wit h rhe expertise relevant to t he acti viry in q uestio n. " (Lipma n, 200 2, p203)
I t is perha ps a ppropriate co in fe r then that in the water industry, d emonstrating d ue diligen ce can includ e the fo llowing elements (D avison , D avis and Deere,
1999):
• Evidence of a culture o f co mpliance (that the system is being adhered to); • A rolling revision pcocess to actively seek ou t and incorporate new knowledge; and • Appropriate contingency plann ing.
Can Compliance with Industry Standards Constitute Due Diligence?
• An assessment of the foreseeable risks to the consumer from source to d elivery point;
In Canadian courts, a two phase ' industry standards tesr' has em erged for the d eterminatio n of reasona ble care i.e.:
• An app ropriate system fo r managing those risks (in the ap propriate regulatory and statu cory co ntext);
1. The standard generally required by that type of business/industry and whether the defend ant took reasonable care; and
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2. W heth er there are particular circumstances that require the defendan t to adop t a higher standard .7 T he test of due diligence in Australia appea rs to rest on th e ' fo reseeabili ty' of th e risk and the practical m easures taken to avoid ic. 8 T hus, a utility would have to co nsid er not only what was available to it in terms of industry best practice, but also an y other issues it needed to take into account to show an appropriate standard of duty. Similarly, relying on g uidel ines m ay not necessarily pro tect a utility if it knows o r has evidence to sh ow that the guidelin es ar e
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business Table 2. Understand ing and managing liabilities: the advantages of a HACC P-based system (Davison el al, 2004) . Relevance to Utility
HACCP Requirement & Implications Explicit understanding and documentation of:
Risks to your intended customers
Involves understanding the types of customers that the utility has, including the environment in some cases.
Risks from product misuse by all
Understanding that customers can misuse water products.
Product specifications Statutory obligations relating to product quality
Understanding the quality that the water product must meet dependi ng on the end use of that water including discharge to a receiving environment or in beneficial reuse such as irrigation of a golf course.
Processes taking place in your system
Understanding the utility's system of operation, not only in its own sphere of influence but where it might be impacted on by neighbouring activities.
Key Point 1: HACCP implicitly requires you to consider the existence of legal duties of care, identify your likely standard of duty and the risks related to the breaching of that duty Requ ires record keeping relating to:
Control of critical processes
Demonstrates that the uti lity is keeping control of processes that are critical to the q uality of its waler products.
Validation of the critical lim its
Recorded evidence to show that limits chosen for controlling water quali ty hazards ore appropriate.
Veri fication that the process is working
Additional evidence that the HACCP Plan is controlling the identified water quality hazards.
Demonstrating that corrective actions have been undertaken
Shows that the utility hos responded appropriately (and in a manner in which it stated it would) lo events that have arisen in relation to water quality.
Key Point 2: HACCP requires you to build a body of evidence to substantiate compliance with good and safe practice Requires independent audit and review:
Second and third party external audit Extra evidence, by provision of outside challenges and peer review, that the of your system system is working to control the identifi ed hazards. Assurance of the quality of raw materials from suppliers
Supply of appropriate standard of materials will facilitate asset longevity and help to reduce costs from breakages and asset replacement etc.
Key Point 3: HACCP requires you to obtain independent review of both your system and your suppliers' systems Requires the development of corrective action plans:
Enables rapid response to contamination events or incidents
Demonstrates that a utility has appropriate systems in place to deal with a waler quality event when it arises.
Requires a traceability and recall procedure
Ensures that the utility understands its system and where its water product is being delivered to.
Key Point 4: HACCP requires you to be prepared for foreseeable contamination events and incidents Key Point 5: HACCP enables you to bring customers into the risk-decision framework
not of an adequate stringency. Risk assessmen t is strongly associated with the demonstration of due diligence: "Due diligence .. .depends on the circumstances of the case, but contemplates a mind concentrated on the likely risks [emphasis added]. "9
However, simply having the system in place will not solely protect the utility and is nor sufficient in and of itself to demonstrate due diligence. In NSW, Grear Southern Energy 10 used consultants to construct an ISO 1400 I system at a cost of more than $ I million but did not provide adequate training to its staff in terms of implementing the plan. Even with the certified system in place, Grear Southern Energy still sustained an oil spill into a creek because of the absence of appropriate
bunding. T he NSW EPA prosecuted and the court awarded damages and a fi ne. However, because of the firm's diligent approach in seeking ISO I 400 I certification, that only limited environmental damage ensued and chat the corrective action procedures in place mitigated further environmental damages, only a$ I 5,000 fine compared to a $125,000 fine was awarded. The importance of established risk management systems was underpinned in chis case as the court found chat the defendant, in the face of using an established system, should be considered as a responsible operator in relation to the environmen t. Similarly, the HACCP principles were used by Pavese Citrus Pry Led to create nor
only food safe bur also work safe pracrices. 11 Even though the risk management system was in place, a person was killed on site by a car parking practice that was judged to have been reasonably foreseeable and that should have been included in the first iteration of the system. Further, the probabil ity of employees disobeying the Employee Procedure Manual or the oral instructions given by Mr Pavese was also identified as a risk by rhe court and one char was not adequately addressed - chus leadi ng to the eventual death of an employee. In sum mary, the risk was identifiable and already known to the defendant, a practice could have been instituted to eliminate chat risk and it was reasonably practicable fo r the defendant co comp ly with the provisions of the Occupational Health and Safety Act 2000
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business (NSW) through ensuring supervision and safe work practices. Therefore again, simply having a system in place was not sufficient to protect the co mpan y, it is the content and demonstrated training and surveillance of the control measures rhar is important. T here is an attempt in som e jurisdictions to clarify the position of industry practices in terms of due diligence (Lipman, 2002), for instance in Queensland, s 436(3)(a) of the Environmental Protection Act 1994 (QLD) explicitly scares rhar co mpliance with rhe relevant code of practice is a defence to a charge of causing unlawfu l environm ental harm. Further, the administering authori ty of that Act is to keep a register of all approved codes of practice. Given that the Q ueensland EPA has recently released its publ'i c consul tation draft 'Guidel ines for the Safe Use of Recycled Water' (2004) which outline the use of Recycled Water Safety Plans (incorporatin g HACCP), it is feasible that HACC P cou ld be incl uded in such a register of approved codes of practice (Environmental Protection Act 1994 (QLD) s 540(m)). However, the recently introduced Safe Drinking Water Act 2003 (Vic) in Victoria, which mandates risk management plans for utilities, bu lk water suppliers and water storage managers, does not specifically mention industry practices such as HACCP or mention due diligence as a defence. It is possible, however, that the due diligence defence could be invoked under other relevan t legislation such as the Food Act 1984 (Vic) 12 â&#x20AC;˘ Further, utilities also need to be awa re of their obligations to staff under occupa tional health and safety legislation, much of which is also now ri sk-based and wh ich also includes a defence of due diligence. U Utili ties also need to be aware that: "The inadvertence or disobedience of insrrucrions by cmployees is nor a defence." 14 T herefore di ligent identification of potential risks (what is reasonably foreseeable) and mitigation of those risks to prevent actua l incidents, co nstitutes an absolute duty on rhe employer. T here is even some suggestion that 'reasonableness' may not necessarily protect an employer: "The duty cast on an employer is both preventive and remed ial in nature and is nor necessarily satisfied by carrying our what ought to be done by a reasonable or prudent person in the circumstances." 15 The onus is therefore doubly on the employer to ensure that it has done as much as it can in identifying and ma naging the risks and in co mmunicating and training its employees as well as ensuring that surveillance is carried out through audits and exam inatio ns to ensu re that employees are complying with work practices.
Risk-Based Systems T here are many risk-based systems available to water utilities including the ISO series of standards (particularly the Environmental Managemenr System standard ISO 1400 1), the AS/NZS Risk Management Standard 4360:2004 and on a more contemporary basis, HACCP (in the fo rm of the broader water safety plan approach) fo r the water cycle (e.g. the World Health Organization's Water Safety Plan guidance for drinking water (Davison et al, 2002). The advantage of using systems such as HACCP and ISO standards, is that a utility can be certified to these systems showing that the system has undergone peer review and deemed to have reached an appropriate representation of that standard. An example of how HACCP can help demonstrate due diligence is given in Table 2.
Conclusions Water utilities need to be aware of their operations as a business and accordingly, acquit their businesses in a duly diligent manner according to the relevant legal framework of their jurisdiction.
refereed paper
Understanding and managi ng risk is a vital component of any business's management and perhaps more so fo r water milities who carry out a range of potentially risky operations such as sewage disposal, sto rmwater management and effl uent recycling. Having a systematic and certified risk management system in place and ensuring that it is implemented and that staff are trained, may faci li tate demonstration of due di ligence fo r utili ties as well as demonstrate that an appropriate standard of duty has been followed. However, utilities should not sol ely rely on industry standards but ensure that th ey keep abreast of the prevailing knowledge in their industri es such that emerging risks ca n be assessed and managed accordingly.
The Authors Dr Daniel Deere and Dr Annette Davison fo rmed ' Water Futu res' in late 2003, and Dan Deere has been a Program Leader with the C RC WQT since 200 I. T heir speciality is water quali ty risk assessmen t. (see Deere and Davison, Water, March 2005), Warer Futures Pry Led, 32 Sirius Sr, Dundas Valley, NSW 21 l 7, Australia, Email annerred@bigpond.ner. au , 04 11 049 544. References Bartley, M. Liabiliry for Water Supply: Lessons from rhe High Court in Puntoriero. Parmer, Phi llips Fox, Solicitors. Unpublished. Davison, A. D., Davis, S. & Deere, D.A. ( 1999) Qualiry assurance and due diligence for water: can HACCP deliver? Presented at Cleaner Production in the Food and Beverage Industry. AWWA Conference, Hobarr 1-3 September 1999.
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business Davison, A.O., Howard, G ., Stevens, M. , Callan , P., Ki rby, R., Deere, D. & Bartram, J. (2002) Water Safety Plans (Draft) . World Health Organization Sustainable Development and H ealthy Environments. Geneva 2002. WHO/SDE/WSI-I/02 .09. Davison, A.O., Pryor, E.L. , H oward, G . and Deere, D.A. (2004) Duly diligent utilities. !WA World Water Congress & Exhibition, 19-24 September 2004, Marrakech. Hurlimann, A. and McKay, J. (2004) G overnance that Builds Knowledge and T rust in Water A uthorities and Positive Impacts on Commun ity Use of Recycled Water. Enviro04 Confere nce, Sydney, 28 March - l Apri l 2004. Lipman, Z. (2002) Corporate and d irectors' liability and due di ligence. In: Pollutio n Law in Australia Lipman, Z and Bares, G (Eds) (2002) LexisNexis Butterworths, Australia, Chapter 5, pp 180-2 11. McKay, J. and Moller, A. (2000). ls it time for a new model of water quality laws/ Environ. Plan. Law}. 17(3), 165-175. Moore, L. (2003) Reclaimed water: managing the legal risks. Water December, 70-74. NHMRC/ARMCANZ (National H ealth and Medical Research Council/Agriculture and Resource Management Council of Australia and New Zealand) (1 996) Australian Drinking ~\1/ater Guidelines.
N HMRC/N RMMC (National H ealth and Medical Research Co uncil/ Natural Resource M anagement Ministerial Council) (2004) Aust ralian Drinking Water G uidelines National W ater Quality Management Strategy. ISBN Online: 186496 1244 Pentony, B., Graw, S., Lennard, J. and Parker, D. (1999) Understanding Business Law. Second Edition. Butterworrhs. Slaughter, J. and Farlegih, A. (2003) Citizens v. utilities: litigation tre nds nu isance and trespass claims against wastewater treatment facilities. AMSA 2003 law seminar, Beverage & D iamond. Telford , P. (1999) A Case Note: Puntoriero v Water Administration M inisterial Corporation. Gadens Lawyers.
Law Citations I. Trade Practices Act 1974 (Cth) s 75AZC, False or misleading representations, ss (]) . 2. Trade Practices Act 1974 (Cth) PART VA
3. Trade Practices Act 1974 (Cth), s 80. 4. Water Administration A ct 1986 (NSW), wh ich was recen tly repealed by the Water Management Act 2000 (NSW) and hence a different sec of imm un ity provisions, was the subject of inrerpretation in Puntoriero and A nor v The Water Administration Ministerial Corporation (1999 Australian Torts Reports, 8 I , 520). Al th ough rhe particular legislat ion
is not in fo rce, the principles established can generally be appl ied. 5. He Kaw Teh vs R (1985] 157 CLR 523. 6 . Lord O iplock in Tesco Supermarkets ltd vs Nattrms (1 972] AC 153 at 199 . 7. R vs Gonder (1981 ] 62 CCC (2d) 326 (Yuk Terr Ct).
8. EPA vs Ampol [ 1995] NSWLEC I 6 as d iscussed in Lipman (2002).
9. State Polfution Control Commission vs Kelly [199 I ] 5 ACSR 607, H emmings J. 10. EPA vs Great Southern Energy, NSWLEC 192 (3 1 August 1999) 11. Inspecto r Templeton v Pavese Citrus Pty ltd [20041 NSWIRComm 322 (29 October 2004) 12. Food Act 1984 - Seer l 7e, Defence of due d iligence. 13. E.g. Occupational Health And Safety A ct 2000 (NSW) - s26. 14. E.g. Rileyv Austmlian Grader 103 IR 143; \ÂĽlorkCover Authority of New South Wales v Blacktoum City Council 124 IR 59 . I 5. Hungerford J in WorkCover Authority of New South Wales (Inspector Keelty) v Crown in Right of the State of New South Wales (Police Service of New South Wales) (No 2) (200 1) 104 IR 268 .
LEGAL AND COMMERCIAL ISSUES IN PRIVATE SECTOR DESALINATION PROJECTS J Ricketts, K Jagger, M Cave Introduction For legal and political reasons, water se rvices have traditionally been provided by government agencies or quasi-government agencies. Risk lies wi th the government agencies, who are accountab le fo r providing the water services. T he legislative regime supports the model by placing restrictions on priva te participation in th e water industry, without being licensed. However, the pressure is on government to find new and innovati ve sources of water. Implementation of new water sources is expensive. It involves investment in new technologies and, usually, significant upfront capital investment. In an attempt to defray the cost of implementation, government agencies loo k to involve the private sector in the development and management of projects. For desalination the tech nology, typically, is with rhe private sector. The private sector ca n also be involved in many desalination proj ects around the globe, whereas government parries are geograph ically restricted and can therefore be restri cted in their experience. Access to technology and experience has also encou raged government sponso rs to turn to the pri vate sector to design, build, finan ce and operate desalination facilities and solve, at least partially, the pressure on governments to provide new sources of water. This paper will examine some of the legal and co mm ercial issues involved in the implementation of desalination projects by the government with the private sector. A thorough appreciation of the issues involved in the desalination project is essential to structu ring the mosr appropriate model for the project. This paper looks at 6 issues (although the last three will be touched on only briefl y): • inputs and outputs of the process; • land issues; T his article is d rawn from the talk of rhe same title del ivered at the AW A Specialty Confe rence in Adelaide o n 23 February 2005.
• regulatory issues; • the ultimate transfer of assets to the government partner; • issues likely to be raised by fin anciers; an d • tax iss ues.
The Models Because of the capital costs involved, many desalination projects have been implemented th rough a BOOT (Bui ld, Own, Operate, Transfer), BOO (Build, O wn, Operate) or similar models. This means th at the desali nati on facility is built, owned and operated by the private sector partner and so metimes, although not always, transferred to the government partner at the end of the project. T he priva te secto r muse fi nance the cos ts of construction up-front, an d recovers the costs and profit through a long term tariff for the provision of water payable during the operation phase. The tariff is usually constructed in two parts, one related to the fi xed costs of the project and the other based on th e variable coses of the project, calculated on th e basis of rh roughput.
This paper focuses on the BOO (T ) model.
The Players The players in desali nation projects are as fo llows: • rhe government sponso r - this may be a govern ment or quas i-government agency; • the concession co mpany - this is usually a special purpose vehicl e, incorporated fo r the specific purpose of undertaking the implementation of the desali nation project; • th e shareholders - th ese are the shareholders in the concession co mpany; the parties wh ich provide the equity contributi ons, th e expertise and the guarantee of the concess ion co mpany's obligations. These are the parties that th e govern ment sponsor is really interested in when it selects its partner fo r the project; • the fina ncier - needs to be incorporated into the contractual model if a BOO (T ) model is chosen to implement the project. If there is proj ect finance, the financier's interest must be kept in the forefront of the minds of the other parties, in order to ensure that the proj ect is "bankable" and fin ance will be provided;
... the appreciation of the commercial and legal risks in a desalination project with a private sector partner must be thoroughly understood. Desalination projects have also been implemented using a DBO (Des ign, Build, Operate) model. In chis model, the governm ent partner retains ownership of the desalination facility at all times, bur contracts with the private sector partner to design, construct and operate the desalination facility. Payment is then for the provision of co nstruction and operation services. lt can be on a lump sum, turn-key basis, or a direct cost reimbursement with corporate overhead and profit, or a hybrid of many different payment elements. However, fo r this model, the private sector partner is not requ ired to finance the project.
• the EPC Contractor - the concess ion co mpany will usually subcontract the actual engineering, procurement and co nstruction obligations to a specialist co mpany, which may or may not be related to the concess ion company; and • the O& M Contracto r - similarly, the operations and maintenance obligations may be subcontracted by the concession co mpany;
Inputs and Outputs Energy Desalination techn ologies can be very energy intensive. It is usual for the
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business con cession company to be respo nsible for procuring sufficient energy for the purpose of operating the desalination fac ility. The risks are: • the contract for rhe supply of electricity will usually be much shorter than the operation phase of the contract, meaning there is no guarantee as to the supply of electricity; • in particular, price of electricity is not guaranteed th rough th e term of the water supply agreement, which affects the assumptions informing the payment model. The price of electricity can be critical co the cost of the project. Risk in the price of electrici ty ca n be dealt with in several ways: • the risk is assigned to the co ncession company - the element of the tariff attributable to electricity remains static (subject to indexation). This is not always acceptab le to the finan ciers, as an increase in the cost of electricity will decrease the revenue stream and , th erefo re, the ability of the co ncession company co repay its debt. • the risk is assigned co the governm ent sponso r - the cost of electricity becomes a pass th rough expense chat varies the tariff accordingly. I n this case, the government sponsor may want to take over the
electricity sup ply arrangements itself, in order to negotiate the best possible price for electricity. This is particularly the case if the government sponso r has favourab le relationships with electricity providers. • the risk is assigned to the sharehold ers or shared between the parties - the parent company or parent compan ies of the co ncess ion company must guaran tee the electricity prices. T he cost of electricity up to the guaranteed level will be paid by the government spo nsor. If the guaranteed price of electricity is exceed ed , the parent co mpany pays the excess . Seawater Quality
D epend ing on the techno logy used, the ability of the desalination plane to deli ver water to the requi red standards is p robably dependent o n assumptio ns as to the quality of seawater being taken into the d esalination p lant. This is because the desalination plane will have bee n designed
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• the ri sk is assigned to the concessio n co m pany - in that case, the co ncessio n company will have to design the desalination plant to take into account a shift in seawater qual ity. If this increases the co st of des ign, constructio n or operation, the cost will b e passed on to the govern ment sponsor in the tariff for the whole of the term of th e contract. • the risk is assigned to the government sponsor - once seawater q uality m oves o utside agreed thresholds, the government sponsor and the concession company will agree on design and operatio n mod ifi cations to be m ade to the d esalination plant and any co nseq uential adjustment to the tariff co rake in to account cap ital expenditure or increased operation costs. The occurrence of this issue may also trigger force majeure provisions in the contract.
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A movement in seawater quality standards may affect the ability of the desali nation plan t to m eet the water quali ty standards. Dependi ng on the paym ent mechanism, chis is likely to reduce the co ncess ion co m pany's payment, by way of disincentives for failure to meet perfo rman ce param eters. T he risk can be dealt with as fo llows:
T he contract will state the required quality o f water that is to be produced as a result of the desalination process. T he q uality parameters will be set to ens ure the qual ity of water being d elivered into the water transmission system , and therefore, to the gen eral public.
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to take into account the existing quality of the seawater, within certain tolerance levels. T his is why pre-testing quality is very important. If a plant is constructed based on fau lty quality informatio n, then it can be very expensive to retro-fit pre-treatment p rocesses .
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Emissions T he con tract will usually state levels of em issions at the d esalination plant, that must not be exceeded during the operation of the desalination plant. The levels will be set in conjun ction with the relevant environ mental authority. Compliance with the set levels must be continuo usly m onitored. Breaches may lead to a reduction in the tariff and to environ m en tal prosecu tion. Depending on the statutory model, each party may be at risk of environmental p rosecution .
Land One of the essential elements of the d esalination project is securing the most appropriate sire. The sire must be ab le to con nect to all of the n ecessary inputs includi ng, of course, seawater. Land may become the responsibility of either party . In some cases, the government sponsor has preferential arrangements with respect to land. In those cases, it may be appropriate for the government sponso r to
Water Resources
acquire the land (either freehold or leasehold) and lease the land to the concession co mpany. In other cases, the govern ment spo nsor may nor wane to be involved in rhe selection of rhe site. In rhose cases, the concession company wi ll be asked to provide rhe derails of a proposed sire as parr of its tender. [ssues chat arise with respect to land are as follows.
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T he length of the tenu re is importa nt, given that the operations phase of the co ntract is likely to be berwee n 20-30 yea rs long. Native Title and Aboriginal Heritage Actual an d potential native ti tle and Abo riginal heritage claims muse be identified as early in the project as possible. Reso lution of the enciti emenc to access the lan d can be a lengthy process and is fu ndamental to the projecr proceeding. Therefore, it is important rhac any potential issues are identified and the resolution of those issues is incl uded in the project ma nagement plan. l e is importan t to obtai n specialist advice in respect of these issues.
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Transferability
The land musr be able to be transferred to the gove rnment sponsor at the end of the term (if the desalination facility is being transferred to rhe government sponso r) or upon early termination of the co ntract (if rhe govern ment sponsor is en ci ti ed or obliged to purchase the desalination fac il iry) .
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Access
The govern ment sponso r will usually have access rights to the desali nation facili ty under the co ntract. Access will be fo r rh e purpose of monitoring and also the exercise of step-in rights in the event of a breach by the concession company rhar puts the desalinarion facility or the delivery of water ar risk. The arrangements wi rh respect to land muse rake into account rhe exercise of the government sponso r's rights to access the desalination facility in the manner co ntemplated under the contract.
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Interconnections
The desali nation facility will connect to the govern ment sponso r's or private off-takers transmission system. T he interco nnection may also be rhe point at which the quantity of water is metered, in order to calculate the tariff T he operability and accuracy of the interconnections is important. T herefore, it muse be considered: • Who owns rhe intercon nections ? • Who has to construct rhe incerconnecrions? • Who operates, maintains and manages rh e interconnections?
Regulatory Issues T he above issues rhar we have discussed also have additional regulatory issues. For example, environmental approvals will be required to operate the desalination plane, and planning approvals will be required to construct the desalination plant. This is part of a broader issue that is inherent in all public private partnerships. In a pub lic private partnership or BOO(T) contract model, the government partner rakes on a dual role. [c is a com mercial parry co an agreement fo r the provision of services. However, it also has a regulatory role, in rhar it may be required to grant licences to the co ncession company to treat water or ro have access to land owned by third parties. T he governm ent sponsor
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business may also be responsible for regulating the co ncession company's activities under legislation. For example, there may be barriers to private sector involvement in the wate r industry, witho uc concessions granted by the government partner.
usual for the govern m en t sponsor to enter into an agreement with the co ncession company and fo r the fi nanciers to endeavour to limit the exercise of con tractual step-in rights in certain circumstances.
arrangements with respect to the land (e.g. rent) are fixed co a known formula.
T he reason that this is an issue is that a contract is drafted to create a co mmercial balance between the parties, governing th e exercise of their rights and obligations, and is intended to be all-encompassing. If the government partner the party to the contract also has statutory powers, the commercial balance created under the con tract becomes uncertain , to the exte nt that it can be d istu rbed by the exercise of those srarntory powers.
Application of Insurance Proceeds
Fi nally, there may be security interests over the project, in favou r of rhe financ iers or other trade debtors, which must be discharged before the p roject is transferred.
For example, the contract may scare that it is a requirement that the concess ion company obtain a licence to operate the desalination plan t. Assume chat the government partner is the party respo nsible for granting the licence. If the government partner does not grant the licence, the concession company is in breach of the contract. The same issue applies co the renewal of licences, to ch anges in the terms of a licen ce an d even co a change in the way that a government partner administers policy. This is an issue that fina nciers are very in terested in.
If the government partner has th e power to exemp t the concession company from licensing requi rements or regulatory reporting requirements, the issue is less important. T he governmen t partner is able to fulfil those functions that would otherwise form part of its regulatory role by exercising carefully drafted rights under the contract. However, if the government partner cannot or will nor fe tter the exercise of its statutory righ ts, there is a conflict that has co be carefully managed by rhe govern ment partner, in co njunction with the concession company and the financiers.
Financiers' Issues The financiers will review the contract documentation to determine the level of control char a governm ent sponsor has of the p roject and , therefore, rhe effe ct on the security of the fi nancier's interest in the project. We will just briefly couch on some of the commercial issues that financiers of a desalination project will consider when reviewing the contract documentation.
Step-in Rights
If the government sponsor has extensive step-in rights, that makes the project more risky from a finance perspective. It is quite 64
MAY 2005
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If the desalination plane is partially or totally destroyed, and a claim is made on the insurance, the financiers may nor, in all circumstances, wane the proceeds of the insurance claim co be paid to rectify the damage to the desalination plant. Instead, the fi nanciers may wane the right to consider whether repairing the desalination plant will guarantee the op eration of th e plant to its previous sta ndards, therefore ensuring the continued revenue stream co rhe concession company to repay debt.
If the revenue scream can not be guaranteed, the financiers are likely co require the insurance proceeds co be paid directly towards satisfying debt. Calculation of the Purchase Price Upon Termination of the Agreement The financiers will look at whether there is an op tion for the government spo nsor to purchase the plant if the contract is terminated early. If the contract is terminated as a result of a d efault of the government sponsor, that option may be an obligation on the government sponso r. The financi ers will look at how the purchase price of the plane is calculated, to ensure that, in all circumstances, its debt can b e repaid.
Transfer of Assets An essential element of a BOOT m odel is chat the assets comprising the project are transferred at rhe end of the term of the contract, or u po n early termination of the p roject. The reason for the transfer is because there is value left in the assets and, usually, the infrastructure is required by the governm ent partner co continue providing services. There are two issues: • how will the transfer be given effect to; and • what w ill the governm ent partner pay for the assets.
How will the Tran sfer be Effected? We mentioned earlier that the arrangements with respect to land must allow for the transfer of tenure co the government partner. The tenure must also be renewable, to ensure chat the government partner is able to continue co use the desalination facility. For the same reason, it is important that the pricing
In addition co land, all permits and authorisations in respect of the desalination project muse be able co transferred to the go vernment partner.
One way of making the transfer easy is to transfer ownership of the concession company to the government partner. Then , the arrangemen ts with respect to ownership and operation of the desalination fac il ity remain in place . T his will depend on rhe ability of the government party to take ownership of a proprietary li mited company.
Purchase Price Ir is usual for the purchase price to vary, depending on th e circumstances of termination . If the governm ent partner breaches the contract, che pu rchase price may encompass lost profit, or be for market value. If the contract is terminated for breach of the concession company, the purchase price may be calculated by reference to outstanding deb t. The determ ination of the purchase price must take into account: • guaranteeing the repayment of debt fi nancing in o rder that rhe financiers do not deem the project to be "unbankable"; • the structure of any other financing arrangements and the effect that termination has on rhose arrangements, including any security that may be held over the assets of the project; and • section 5 1AD and Division 16 of the
Income Tax Assessment Act, which are affected by arrangements with respect to the purchase of infrastrncture at the end of a public private partnership p roject and which, if adversely applied, may affect the rax deductions which a concession company may claim during the operation phase of the p roject.
Tax issues Previo usly, we mentioned char the difference between a BOO(T ) project and a DBO project is that the BOO(T) project is owned and finan ced by the p rivate sector. Section 5 lAD and Division 16 of the Income Tax Assessment Act are directed towards preventing arrangements b eing put in place that allow private companies to rake advantage of a government sponsor's tax exemp t status. Thar is, the ATO looks at an agreement between a government sponsor and a private party to
determi ne whether, in fact, rhe project is being fi nanced by rhe government sponsor on a long term basis. T he reaso n to be aware of these provisions is rhar they prevent rhe concession company from being able to claim certain rax ded uctions. T hese provisions apply if it can be established rhar the government sponso r has control of the project. H owever, there is no defi nition of contro l. T herefo re, ir is usual fo r private parries to obtai n a tax ru ling from rhe ATO to determi ne whether rhe particular sections apply. Key indicia of control are as fo llows: • the government sponsor has the right to step-in to rhe project in circumstances other than emergency circumsta nces; • the concess ion co mpany is prevented from providing water to any parry ocher than rh e government sponso r; • the co ncession company's rernrn for rhe project is guaranteed by the govern ment spo nsor; and • rhe calculation of the purchase price payable by the governm ent sponso r upon termi nation of rhe project indicates a fi nancing arrangement. However, note rhar each case is interpreted on irs ind ivid ua l circumstances, considering the justifications for rhe government sponso r placing restrictions on rhe private parry. l t is also worth noting that there are reforms on fo ot in respect of these sections that may rake effect from as early as Ju ly 2005. The reforms are ai med at making rhe tax provisions more " PP P fr iendly" .
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Conclusion As we stated in the introductio n to this pa per, the appreciation of th e commercial and lega l risks in a desalination project with a private sector partn er, must be thoroughly understood in order to ensure rhe success of the project. T he parries must determine which risks are most appropriately allocated to which party - that is, which parry is best able to manage the risk. Given that rhe contracts are normally lengthy - 20-30 years - there are many factors that can change the environment in which the co ntracto r is operating. Jn order to min imise bui lding in conti ngencies (which will ultimately be paid for by th e govern ment sponso r) the government sponsor will usually cake on some of the risks. In that case, upon occurrence of the risk, rhe commercial terms of rhe co n tract can be renegotiated or subj ected to a predeterm ined adj ustment process.
In other circumstances, given the natu re of rhe risk, the risk is more appropriately borne by the private partner, due to level of experience and ability to co ntrol the conseq uences of rhe risk occurring. Most importantly, the interests of all of the parties involved in the proj ect, co ncession co mpany, shareholders, government sponso r and fi nanciers, muse be kept in mind to ensure an outcome that satisfies each of chose interest.
The Authors Jason Ricketts and Ken Jagger are Partners and Melanie Cave is a Senior Associate with Freehills, G PO Box Ul 942, Perth, WA, 6845. Phone 08 9211 7777. Email jason.rickerrs@freehills.com
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Water Business aims to keep readers alert to business news and new product releases w ithin the water sector. Media re leases shou ld be e m a i led to Bri an Rau lt , brault@halledit.com.au , or Tel (03) 8534 5014. seminars. It provides a p ractical introductio n co the world of pumps and their applications. T he two companion seminars to ' Pump Fundamentals' deal with higher level pumping equ ipment and system issues. KASA Solutions is an ind ependen t organisation withou t ties to any manufacturer or supplier and can therefo re offer an unbiased training or consulting solution.
Contact KASA Solutions on (02) 4753 7647 for more information on this series of seminars as well as others on offer. Alternatively, visit the KASA Solutions website: www.kasa.com.au. (Please note that more detailed seminar information and a registration form will appear in the Ju ne edition ofthis j ournal.
WATER TREATMENT SOLUTIONS EIM CO Water Technologies offers a diverse range of water treatment equipm en t o f medium to large sizes to carer for the drinking water, sewage and industrial wastewater treatment markets. P rocesses covered include virtually all stages of treatmen t from screening and grit collectio n to clarification, biological treatment, nutrient removal, filtratio n, and fina lly d igestion and sludge handling.
The EIMCO Reactor-Clarifier™ solids contact unit is designed and built co provide che most economical solution to
precipitation and clarification requirements. The basic machine design provides for coagulation, flocculat ion, solids recirculation, clarificatio n and positive sludge removal in a single basin, eliminating the need fo r multiple ran ks and associated piping . Typical ap plications include che removal of turbid ity, algae, colour, iron and ocher metals from drinking water; tertiary wastewater treatment for phosphorus and solids removal; effluent treatment; water softeni ng; and brine clari fication. T h e EIM CO Reactor-Clarifi er unit combines slow speed turbine flocculation and high volume internal recirculation to promote mixing, fl occulation and solids-co ntact. The recirculation system is d esigned to promote particle growth and improve the removal of suspended sol ids and can b e operated to give recycle rares of up to 15 times the maximum influent rare. Infl uent immediately contacts a large volume of dense fl oe from previously precip itated so lids in the recirculation drum and is pumped upward by a large diameter slow-speed turbine. The heaviest particles settle to the floor where they are raked to the centre for recirculation or discharge. The EIMCO Reactor Clarifier™ solids contact unit can be manufactured in sizes up to 80m in diameter.
For more information, contact (02) 4320 4700.
SOUTH AUSTRALIAN WATER CORPORATION NOMINATED FOR AWARD The South Australian Water Corporation, a public corporation which delivers water and wastewater services to almost 1.4 million people across the scace, has been nominated for a 200 5 BE Award for its Copper Coast Water Supply Master Plan project in Yo rke Pen insula, Sou th Australia. The BE Awards of Excellence are presented at the ann ual BE Conference (www.be.org), an annual gathering of Bentley users and their managers who wane to sharpen their skills and expand their knowledge at over 300 training, best practice, new technology, and keynote sessions . T he BE Conference 2005 is being held May 8-12 in Baltimore, Md.
SewerGEMS MULTI-PLATFORM SEWER MODELLING SewerGEMS from Bentley's Haestad Methods product line is a comprehensive multi-platform (stand-alone, CAD and GIS) and fully dynamic modelling and management solution for the design, analysis, and planning of sanitary and combined sewer system infrastructure. For more information about this innovative software, see the inside front cover of the May issue of Water Journal, visit www.bentley.com/sewergems/AWA, or e-mail sales.haestad@bentley.com. 66 MAY 200s water