9.1 National Water Commission (NWC)9.2 Sydney Water: policies to water

reclamation9.3 Sydney Olympic Park (SOP)9.4 Wollongong Recycled Water Plant 9.5 Gold Coast Water: demand and

drought management 9.6 Pimpama Coomera (Gold Coast

Water)9.7 Brisbane Water’s recycling strategy9.8 Luggage Point Wastewater

Treatment Plant9.9 The Toowoomba experience with

public consultation9.10 New Farm Park water mining project9.11 Rocks Riverside Park water mining

project9.12 SA Water and United Water overview9.13 Australia’s National Guidelines for

Water Recycling9.14 Cooperative Research Centre (CRC)

for Water Quality and Treatment9.15 Water Proofing Adelaide9.16 Mawson Lakes water recycling and

dual reticulation scheme9.17 Bolivar/Virginia reuse scheme9.18 Melbourne, Victoria and SE Water 9.19 Inkerman Oasis residential

development9.20 The Urban Workshop9.21 Royal Park Wetlands Stormwater

Treatment and Reuse System

9.1 National Water Commission (NWC)

Each state in Australia is responsible formanagement of its natural resources eg landand water. State and local governments areboth involved in water supply. The federalGovernment is involved in co-ordination throughthe NWC. The overall objective is to have ‘anationally compatible market, regulatory and

planning based system of managing surfaceand groundwater resources for rural and urbanuse that optimises economic, social andenvironmental outcomes’.

The NWC is an independent statutory bodyformed by the Australian Government to drivethe national water reform agenda. Establishedunder the National Water Commission Act2004, it provides advice to the Council ofAustralian Governments (COAG) (ie the stategovernments) and the Australian Governmenton national water issues. The NWC has twooverarching roles:

• Advancing the National Water Initiative (NWI)• Advising on and administering the A$2 billion

(£800 million) Australian Government Water Fund

The latter funds two major programmes –Water Smart Australia and Raising NationalWater Standards.

The NWI is the Australian Government’s andstate and territory governments’ sharedcommitment to water reform in recognition of:

• The continuing national imperative toincrease the productivity and efficiency ofAustralia’s water use

• The need to service rural and urbancommunities

• Ensuring the health of river andgroundwater systems

Water Smart Australia aims to accelerate thedevelopment and uptake of smart technologiesand practices in water use across the country.The programme is targeted at large-scaleprojects and has A$1.6 billion (£640 million)available until 2010. The minimum level of

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9 AUSTRALIA SITE VISIT REPORTS

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funding for a project is A$1 million (£400,000),the maximum duration is four years. Anexample is Water Proofing Adelaide (seeSection 9.15). Raising National Water Standardsis designed to improve Australia’s nationalcapacity to measure, monitor and manage itswater resources. A total of A$200 million (£80million) over five years has been allocated.

9.2 Sydney Water: policies to water

reclamation

The severity of the ongoing multi-yeardrought has necessitated the fast-tracking ofnew water reuse initiatives, over and abovethe historic schemes, which were mainly forirrigators. The New South Wales Governmenthas developed the 2006 Metropolitan WaterPlan, which provides the framework and thefunds. Sydney Water, which operates over anarea of 12,620 km2, set up a dedicated teamto implement the plan.

Compared with 15 billion l of recycling as ofJune 2006, the Metropolitan Water Plan aimsfor 27 billion l/y of recycling by 2029, witheventual aspirations of 70 billion l/y, which

equates to 12% of potable demand (seeExhibit 9.1).

The proposed recycling schemes are for non-potable uses including residential, industrial,agricultural and environmental purposes. Theyconsist of a portfolio of projects including dualreticulation at new developments, constructionof a new pipeline dedicated to distributesecondary effluent with thoughts of a futurerecycled ‘water grid’, sewer mining and flowreplacement. IPR is not currently beingconsidered. The key urban schemes currentlyin progress are as follows:

Dual reticulation – domestic properties

The Metropolitan Water Plan gives acommitment to providing recycled water viadual reticulation to all new homes in Sydney’snorthwest and southwest growth centres. 70%of Sydney’s new growth will be ‘in-fill’. RouseHill was the 2002 showcase with recycledwater for outdoor use and toilet flushing. Thescheme is now expanding to 15,000 homeswith consideration of additional use for washingmachine cold taps. The original technology wasMF but this has subsequently been changed todeep-bed filtration followed by UV. The schemescomply with the New South Wales reclaimedwater guidance documents and requiresignificant operational resources, eg continuousmonitoring, cross-connection checking,community engagement, plumbing inspectionsand signage. The range of stakeholders that need consultation runs to more than 25 including residents, landscape gardeners, firebrigades, swimming pool operatives, doctors,chemists, estate agents etc.

Sewer mining

Sewer mining is used to provide effluent forSydney Olympic Village, where MF/ROprovides the treatment for the Olympic Parkdual reticulation scheme (see Section 9.3).Other smaller scale localised sewer miningprojects are also being considered.

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Exhibit 9.1 Recycled water use in Sydney (courtesySydney Water)

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Industrial use

Industrial use is seen as one of the bestopportunities for reclaimed water use. Thefirst scheme was in Wollongong, a coastaltown south of Sydney in which RO-treatedeffluent provides 20 Ml/d of reclaimed waterto BlueScope Steel (see Section 9.4).Following its success the Camellia RecycledWater Project is being progressed. This hasthe objective of providing 6 billion l/y ofrecycled water for a cluster of industrial usersvia private ownership, with the opportunityfor future expansion.

Replacement flows

One of the most interesting schemes is theHawkesbury-Neapean flow replacementproject. The aim is to build a 50 Ml/d ROadvanced water treatment plant to treateffluent to a higher standard and direct itfurther upstream to enhance the flows in theHawkesbury-Neapean river system. This willmean that the release of environmental flowsfrom the Warragamba dam can cease, savingmore supplies for water treatment purposes.It will also result in a significant qualityimprovement in the river system.

Some of the emerging issues Sydney Wateris finding with reclaimed water are:

• Third party access to the water• Private and decentralised systems• Sewer mining• Long-term liability for unknowns

9.3 Sydney Olympic Park (SOP)

The evolution of SOP, with the transformationof a polluted, industrial site into the iconichome of the 2000 Olympics and adevelopment master plan to 2025, is wellpublicised (www.sydneyolympicpark.com.au).The project included much communityinvolvement with the formation of lobbyinggroups such as ‘Green Games Watch 2000’.

Water recycling is one important element ofthe sustainable approach to the wholedevelopment of an ‘integrated urban watercycle’ concept, also driven by a need to findalternatives to potable water in response towater scarcity. Known as WRAMS (WaterReclamation and Management Scheme) theapproach includes land rehabilitation, floodalleviation, aquatic habit restoration, stormwater storage and reuse, pollution control andrecreation provision.

Landscape water features include 30 differentconstructed wetlands on the site and adisused brick pit which functions as a storagebasin. The main stadium has 3 Ml/d storagefor rainwater. This water passes through filtersto remove larger debris such as leaves and isused for irrigation eg turf watering at stadium.

As well as the sporting legacy, thedevelopment consists of mixed residentialand commercial buildings in sub-districts suchas Homebush and Newington. Recycledwater is mandatory with every buildingrequired to have a dual supply. Originally thereclaimed water was permitted only for a fewlimited uses such as irrigation of parklandsand toilet flushing, but as acceptance hasincreased this has expanded to over 11 enduses such as swimming pool filter backwashand ornamental fountains.

The reclaimed water quality goals for the parkare based on a combination of the NewSouth Wales reclaimed water guidelines, thedrinking water guidelines and guidelines fromNSW Health, the New South Wales healthdepartment. Analysis confirms that thereclaimed water quality consistently meetsthese stringent quality criteria. In parallel, andconsidered equally crucial, are the numerousoperational procedures such as crossconnection audit, new connection verification,testing and certification that are carried outand supported by extensive public education.Public perception and acceptance areconsidered a key issue.

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The source of the reclaimed water is a ‘sewermine’, supplemented by surface run-off fromthe brick pit when required. The treatmenttechnology is a high-visibility MF/RO plant (seeExhibit 9.2). This has been in operation for sixand a half years. Some membrane replacementhas taken place during this period.

The SOP Authority sees this development asan important step in building public confidencein reclaimed water and demonstrating abalance of social, environment and economicfactors in urban developments. However oneof the key issues going forward is the pricingof reclaimed water. It is currently priced atA$1.11/m3 (45 pence/m3), purposely cheaperthan potable which is A$1.20-1.48/m3 (48-60pence/m3), and the SOP Authority has not yetmanaged to recover the cost of the reclaimedwater under this pricing regime.

In summary, the water use at SOP is 48%recycled, 46% direct stormwater reuse and6% potable. Of the recycled water, 40% isused for toilet flushing, the rest for irrigationand washdown (see Exhibit 9.3).

9.4 Wollongong Recycled Water Plant

Wollongong is an industrial town on the coastapproximately 50 miles south of Sydney. Thewastewater treatment plant was expanded toreplace two works at other sites and nowreceives approximately 70 Ml/d. The waterreclamation plant has been developed on thesame site (see Exhibit 9.4).

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WATER RECYCLING AND REUSE IN SINGAPORE AND AUSTRALIA

Exhibit 9.2 Sydney Olympic Park membrane treatment plant

Exhibit 9.3 Water reuse by the Sydney Olympic Park(courtesy SOP Authority)

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One third of the total flow received is treatedin a conventional activated sludge plant fordirect discharge to sea. The remaining twothirds is treated in a Veolia Water designedbiological nutrient removal (BNR) plant. The tertiary effluent from this plant contains<1 mg/l P; this is only achieved after ferricchloride dosing. This provides the feed for thewater reclamation plant (WRP) (see Exhibit9.5). Any of the final effluent which does notgo to the water reclamation plant is dischargedto the sea via the 1 km long sea outfall.

The processes at the WRP are as follows:

• Pre-treatment is MF through 0.2 µm poresize membranes which treat 27.4 Ml/d,providing 23.5 Ml/d product water and 3.9 Ml/d retentate

• The 23.5 Ml/d product water is fed to afinal stage triple-pass RO in which recoveryis 85-87% producing 20 Ml/d

• Post RO, air stripping of carbon dioxidefollowed by sodium hydroxide addition wasused to raise the pH

• After chlorination, the water was pumpedto a reservoir for provision to the localsteelworks (Bluescope Steel)

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WATER RECYCLING AND REUSE IN SINGAPORE AND AUSTRALIA

Exhibit 9.4 The mission team and host at Wollongong Recycled Water Plant

Exhibit 9.5 Membrane hall at Wollongong RecycledWater Plant

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During the current drought low overnightflows, down from 50 to 40 Ml/d, were aconstraint on plant operation.

9.5 Gold Coast Water: demand and

drought management

Ongoing drought conditions in South EastQueensland, led Gold Coast City Council(GCCC) and the state government to produce astrategy to deal with the water demand ofresidential dwellings, commercial and industrialfacilities. A key goal of the strategy is tomanage this rising demand in order to defer theneed to expand infrastructure to cope with it.

Population is expected to grow from 450,000 to 1.2 million by 2056. Hence the key objective is to reduce water demand by 50 Ml/d by 2056. Considerable informationgaps exist, both nationally and regionally.Therefore, wherever feasible, researchpartnerships with other Australian utilities,academic agencies and other partners arebeing sought.

In December 2005, the GCCC endorsed theGold Coast Waterfuture Strategy (2006-2056).The policy is currently being costed andbenchmarks established.

Sector consumption is:

• Residential 64% • Commercial 22% • Unaccounted (leaks, etc) 12-14%• With a tourist population of 10.7 million/y,

water use in the hospitality sector is 9-11%

Water is often seen by the community as alimitless, low-cost resource. However, thepopulace, used to living with water restrictionscoupled with the ‘Watch Every Drop’campaign, display a high level of awareness ofthe need to limit their consumption.

The Waterfuture Strategy proposes thefollowing tactics, referred to as the 5Es:

• Economic – user pricing and financialincentives to save water

• Education – awareness-raising waterconserving programmes to bring aboutchanges in consumption behaviour

• Encouragement – incentive schemes andmarketing to increase uptake of watersaving products

• Engineering – new ways of planning andmanaging water and wastewaterinfrastructure including leakage control andpressure reduction

• Enforcement – regulatory mechanisms,restriction on use coupled with complianceand enforcement programme

Technologically, stormwater harvesting,recycling water, rainwater harvesting andgroundwater recharge are some of the optionsbeing considered, as well as constructing asouthern regional pipeline by 2007.

Following receipt of state funding of A$80 million (£32 million), the GCCCcommitted another A$20 million (£8 million) toinvestigating the feasibility of desalination asan emergency source. It is expected that theplant will be commissioned by 2008. ROtechnology will be used to produce 125 Ml/d.The plant is estimated to require 28 MW ofpower. A range of options to offset emissions,are being investigated eg biogas, biomass,solar. Studies are being conducted to assessthe ecological impact of brine dispersion.

In 2003 a major initiative was launched toprovide incentives for residential consumersto purchase and install water saving deviceseg water efficient shower rose, dual flushtoilets, garden products, rainwater tanks. It has been estimated that an efficientshower rose can save 18 kl/y. Rebatestotalling A$1 million (£400,000) wereprovided to 9,000 residents over a nine-month period and are estimated to havesaved 160,000 kl/y.

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All new builds are expected to providerainwater tanks and recycled water for toiletand garden irrigation use.

Industrial/commercial customers use recycledwater. Currently 59 units are being suppliedwith recycled water. It is also used for openspace irrigation eg golf courses, parks.Treated water is delivered to customers by apipeline network as well as a recycled watertruck supply system. The recycled waterstrategy runs in tandem with the demandmanagement strategy. The current target is tobeneficially reuse 14% of recycled waterreleased from treatment plants. The objectiveof the recycled water strategy is to ‘ensurethe sustainable use of recycled water withinthe framework of the total water cycle’.

In order for the Waterfuture Strategy tosucceed, user behavioural changes areessential. Countervailing social trends – eggreater interest in home gardening – couldcounteract the efforts. Furthermore,considering the voluntary nature of mostprojects in the scheme, social perceptions (egof recycled water safety, of the quality ofwater efficient showers) are key to success.Demand management marketing mustanticipate and proactively respond to suchconcerns and monitor compliance withsuitably equipped and trained officers (seeExhibit 9.6).

Water efficient technology is improving at adramatic rate. Demand managementprogrammes must be designed to capitaliseon these changes.

9.6 Pimpama Coomera (Gold Coast

Water)

Introduction

In response to South East Queensland’sworst drought on record, Gold Coast Water(GCW), a department of Gold Coast CityCouncil, has developed the Gold CoastWaterfuture Strategy (2005-2056), whichaims to be a diverse and sustainable long-term plan to provide a secure water supplyfor future generations across the region.

Pimpama Coomera Master Plan

At Pimpama Coomera, GCW is implementingthe water management Master Plan, whichcontains many of the elements identified inthe Waterfuture Strategy.

The Master Plan (see Exhibit 9.7) covers alargely undeveloped area of 7,000 ha in thenorthern Gold Coast, 40 km south ofBrisbane, and includes commercial,residential and industrial developments in sixsuburbs. It has a current population ofapproximately 15,000, but is expected togrow to 120,000 over the next 50 years.

Key elements of the plan include:

• All new homes to have three differentsources of water:

° Class A+ recycled water – for toiletflushing and external uses

° Rainwater – for cold water washingmachine taps and external uses, butultimately for all laundry and bathroomtaps and hot water

° Potable water – for kitchen use only

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Exhibit 9.6 Water patrol car for assisting withcustomer compliance

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• Stormwater management will be improved with:

° Implementation of Water SensitiveUrban Design (WSUD) similar to theUK’s SUDS programme

° Rainwater harvesting to capture cleanwater in the home

• The use of SMART (watertight) sewers toreduce the stormwater and groundwaterentering the wastewater system.

• Education and communication to ensure theentire community is informed and involvedin the Master Plan implementation.

It is estimated that after implementation ofthe plan, the consumption of high quality

drinking water in the home will be reduced by84%. Exhibit 9.8 highlights the anticipatedwater use by source.

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WATER RECYCLING AND REUSE IN SINGAPORE AND AUSTRALIA

Exhibit 9.7 Pimpama Coomera Master Plan region (courtesy Gold Coast Water)

Exhibit 9.8 Pimpama Coomera anticipated water usefrom different sources (courtesy Gold Coast Water)

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Construction phases

Construction of the infrastructure necessaryto implement the plan has been divided intofour different ‘packages’ of works. Theconstruction packages will be implementedprogressively over the next three years. Eachpackage consists of the following:

Package A – Pimpama wastewater andrecycled water treatment plantsThe Pimpama water treatment facility,comprising a wastewater treatment plant anda recycled water treatment plant will beconstructed. Stage 1 of the wastewatertreatment plant will be completed andoperational by November 2007.

Conventional treatment processes are beingused to treat the wastewater to a 3 mg/l Nand 1 mg/l P standard. The effluent is thenprocessed through the recycled water plantusing a sand filter, followed by MFmembranes, UV disinfection and chlorination.

Stage 1 of the recycled water treatment plantwill be delivering up to 9 million l of Class A+recycled water per day to dual reticulatedhomes (see below) and businesses in thePimpama Coomera region by late 2008 fortoilet flushing and external uses.

Package B – Wastewater trunk mainA new wastewater trunk main will be built tocarry the region’s wastewater to the newtreatment plant.

Package C – Pimpama to Coombabahrecycled water pipeline A recycled water pipeline will be constructedfrom the new treatment plant site to an existingtreatment plant at Coombabah to allow forrecycled water not used within the communityto be released via the Coombabah system.

Construction commenced in December 2006and will be completed by November 2007.

Package D – Water network mains,pumping stations and reservoirsAdditional potable water, wastewater andrecycled water network mains will be built tocater for the increased demand of water andwastewater requirements of the rapidlygrowing Pimpama Coomera region. Potablewater and recycled water reservoirs mustalso be built as part of the entire waternetwork. A small number of pumping stationswill be constructed to distribute potable waterand Class A+ recycled water and to pumpwastewater to the new treatment plant.

Dual reticulation

All homes in the region approved after 29 August 2005 have been plumbed withseparate purple pipes to provide the Class A+recycled water. Homes connected to bothpotable and recycled water are known as‘dual reticulated’ with a clear colour codingfor the two types of water (see Exhibit 9.9).

Until Class A+ water is available towards theend of 2008, potable water will flow throughthe recycled water network.

Dual reticulated homes will be fitted with oneor more external recycled water taps whichare also purple in colour and fitted with aremovable handle and warning sign to avoidconfusion or misuse (see Cover).

Rainwater harvesting

As for the rest of the Gold Coast, all newhomes built in the Pimpama Coomera regionare required to install a rainwater tank (seeExhibit 9.10). The tanks need to be a minimumof 3,000 l for those homes connected to Class A+ recycled water. Homes approvedafter 10 June 2005 but not connected torecycled water need to have a rainwater tankwith a minimum 5,000 l capacity.

As part of the state government’s drive toencourage uptake of water saving devicesacross the state, rebates are available to

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residents on the purchase of rainwater tanks.The rebate for tanks greater than 2,000 lcapacity is A$200 (£80) and for tanks greaterthan 7,000 l capacity it is A$500 (£200). Thedemand for rainwater tanks has outstrippedsupply, resulting in a six-month delivery onthem.

9.7 Brisbane Water’s recycling strategy

Brisbane Water is one of Australia’s largestwater utilities supplying water to 975,000people in Brisbane and 1.7 million peopleregionally. The utility is a business unit ofBrisbane City Council: the council owns theasset base and Brisbane Water operates afranchise to maintain and operate the waterand wastewater network.

Brisbane’s network consists of 6,300 km ofwater mains, 3,000 km of water connections

and 6,800 km of sewer mains. Its clean waterassets supply 700,000 m3 of potable water toBrisbane and six other regional councils perday and serves 420,000 properties. The assetsconsist of four potable water treatment plants,

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WATER RECYCLING AND REUSE IN SINGAPORE AND AUSTRALIA

Exhibit 9.9 Meter covers – green for potable water, purple for recycled water

Exhibit 9.10 Completed house showing plumbing for arainwater tank

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three dams, 43 reservoirs, 20 pump stationsand 71 water boosters. Its wastewater assetstransport and treat over 300 Ml/d of sewageand serve 411,000 properties. The regioncurrently recycles/reuses 15 Ml/d of itswastewater outputs. The assets consist of 10wastewater treatment plants, two recycledwater plants and 204 pumping stations.

As of 1 November 2006, Level 4 waterrestrictions apply throughout the region. Thedrivers for Brisbane Water are very similar toneighbouring Gold Coast Water. Population isforecast to grow with regional water demandcontinuing to rise as a result, the forecastincreases coming at a time when the regionis in the midst of a severe drought. Exhibit9.11 depicts the comparison of water needsand availability in South East Queensland. Theregion’s demand is forecast to outstrip supplyby between 2012 and 2025 depending on thelevel of water saving and reuse measuresthat achieve successful implementation.

Understandably, there is a view that a newparadigm is required that moves away fromthe traditional ‘end of pipe’ type urban watercycle to a more integrated water supplymanagement involving an array of solutionsincluding recycled water and dual reticulation,indirect potable reuse, sewer mining,desalination, water sensitive urban designsand rainwater harvesting and reuse.

Consumption figures show that almost 75%of the region’s water is allocated to urbanuse. As for many Australian urban centres theper capita consumption is high whencompared to UK figures. In Brisbane the percapita consumption is approximately 330 l/dcompared with an average of approximately160 l/d in the UK. In the urban environment62% of the demand is from residentialconsumption with 46% of residentialconsumption going to garden use. A breakdown of the total residentialconsumption is shown in Exhibit 9.12.

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WATER RECYCLING AND REUSE IN SINGAPORE AND AUSTRALIA

Exhibit 9.11 Water needs and availability in South East Queensland (courtesy Brisbane Water)

Volu

me

(Gl/y

)

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The water recycling strategy

Mr Bruce Hutton, the manager responsible forrecycled water treatment planning, presentedBrisbane Water’s plan to the mission team on28 November 2006. It identified water supplysecurity and efficient resource use as corestrands (see Exhibit 9.13).

Exhibit 9.14 highlights the more specificstrategies in place to achieve a targeted 18%per capita reduction of South EastQueensland dam supply over the period 2001-2010.

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WATER RECYCLING AND REUSE IN SINGAPORE AND AUSTRALIA

Exhibit 9.14 Detailed water saving strategies (courtesy Brisbane Water)

Exhibit 9.12 Distribution of domestic water use(courtesy Brisbane Water)

Exhibit 9.13 Brisbane’s water recycling strategy(courtesy Brisbane Water)

Strategy Initiative % saving Water savedMl/y

Wat

er e

ffic

ien

cy

Non revenue water • Leakage management4% 7,400• Metred standpipes

• Illegal water use

Tariffs and billing • Demand (block) tariff• Separate water advice 5% 9,600

Community education • Industrial customer efficiency• Community education• Schools programme• Blue van• Existing sprinkler restrictions

1% 1,900

Sustainable development

Water efficient design

• New development plans/Rochedale/Oxley Lakes/AustraliaTrade Coast/local areas

1% 1,700• Commercial/residential building codes• Regulation AAAAA appliances

• Efficiency incentives existing development• Rainwater tank rebates• Sustainable housing rebate

Su

bst

itutio

n

Effluent reuse • Industrial use• Sporting and recreational• Commercial reuse• Residential reuse• Agricultural reuse

6.5% 12,400

Other • Rainwater/stormwater• Aquifer/BCC dams 0.5% 600

Total 18% 33,600

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An 11% reduction is targeted at water efficiencymeasures that are regulatory driven and can beenforced. The remaining 7% is targeted atsubstitution measures principally involving reuseof effluent. Brisbane Water has also carried outan exercise on indicative costing for each of thewater balance options being considered andimplemented. Exhibit 9.15 presents abreakdown of these costs together with therisks and benefits associated with each option.It should be noted that these costs have beenprepared on the basis of retrofitting in therelatively dense urban setting of Brisbane.

Under the recycling strategy there are sixopportunities for effluent reuse which include:

Dual reticulation – 20-30% reuse forecast ata cost of A$3.4 billion (£1.4 billion)Agricultural irrigation – 250 km2 ofagricultural land at a cost of A$800 million(£320 million)Municipal irrigation – up to 30% reuse withall municipal parks utilisedIndustrial reuse – 25% of all recycledeffluent can be sold to industrial customers

Aquifer recharge – some opportunities exist Recreation ponding – limited opportunities

There is a range of reuse schemes beingplanned in Brisbane (see Exhibit 9.16). Keycomponents include the Australia Trade Coast(ATC) scheme that aims to provide 189 Ml/dof recycled water for industrial andcommercial reuse at a cost of A$60 million(£24 million). The ATC involved the upgrade oftwo existing wastewater treatment plants atLuggage Point and Wynnum. Further detailson Luggage Point Wastewater TreatmentPlant can be found in Section 9.8.

Rochdale is a greenfield development of 500 ha with a forecast population of 15,000.Dual reticulation and water sensitive urbandesign are key components of the schemewith maximum use of rainwater harvesting forall indoor non-drinking uses (except kitchenand bathroom basin cold water taps). It isexpected that a 74% reduction in potablewater use compared with normal usage will be achieved.

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WATER RECYCLING AND REUSE IN SINGAPORE AND AUSTRALIA

Option Triple bottom line risk/benefit Indicative costA$/kl (£/kl)

Demand management Community uptake – communication subsidy/low cost A$0.20 (£0.08)

Interconnect supplysources

Distance/volume dependent. Water quality deterioration. No new water supply

A$0.20-0.80 (£0.08-0.32)

System lossesmanagement

Good community example A$0.40 (£0.16)

Indirect potablerecycling

Greater public understanding/acceptance needed. Large constant source, minimum risk

A$0.40-1.50 (£0.16-0.60)

Suburb recycling Good quality control. Cross connection/ongoing compliance cA$0.60 (£0.24)

Aquiferrecharge/extraction

Over extraction, environmental impacts. Potable water quality/unlimited end use

cA$0.60-1.50 (£0.24-0.60)

Reuse to industry Big single users/price sensitive. Proximity to treatment plants critical cA$0.90-1.50 (£0.36-0.60)

Stormwaterharvesting/lakes ASR

Offset capital upgrades. Offset waterway discharge A$1.00-1.50 (£0.40-0.60)

Desalination High energy. Brine discharge/reliable source A$1.10-2.30 (£0.44-0.92)

New dams Environmental concerns. Reduced yields/increased safety costs A$1.20-1.40 (£0.48-0.56)

Rainwater tanks Offset capital upgrades. Water quality not drinking A$2-6 (£0.80-2.40)

Household recycling Long-term soil risks. Low energy A$2-6 (£0.80-2.40)

Water mining Offset capital upgrades. Offset waterway discharge. Lack of technology proofing/supply at demand point

A$3-5 (£1.20-2.00)

Exhibit 9.15 Water balance options and economics (courtesy Brisbane Water)

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The Western Scheme is a A$1.7 billion (£680 million) project aiming to provide 200 Ml/d of demineralised water forindustrial residential and agricultural use.

There are a number of other local reuseschemes, two of which – New Farm Park(see Section 9.10) and Rocks Riverside Park(see Section 9.11) – involve sewer mining.

Clearly the Brisbane Recycled Water Strategyprovides for an ambitious programme ofworks principally driven by the need forsecurity of supply. The combination ofdrought and population increase perhapsmakes the challenges more acute than someother regions of Australia. The traditionalapproach to catchment management hasbeen revised to provide for what is hoped tobe a more sustainable, secure supply throughthe recycling of wastewater and wider reuseof rainwater. In the long term desalination andindirect potable reuse are also likely to gainfurther public acceptance in the face of acontinuing drought.

9.8 Luggage Point Wastewater

Treatment Plant

Brisbane Water’s Luggage Point WastewaterTreatment Plant is a large municipal worksfrom which a significant proportion of theflow is recycled to provide high specindustrial water supply. It is a conventionalactivated sludge system with the followingcharacteristics:

• Treatment capacity 870,000 populationequivalents (PE)

• Consent (50 percentile)

° 20 mg/l BOD

° 30 mg/l SS

° 10 mg/l TN changing to 5 mg/l early 2007

° No P consent

• 10 Ml/d are fed to the water recycling plant

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Exhibit 9.16 Distribution of recycling schemes in Brisbane (courtesy Brisbane Water)

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Water recycling plant

The Luggage Point recycling (reclamation)scheme involves the further treatment oftreated sewage effluent using dual membranetreatment prior to supplying it for industrialuse. The key driver for the investment in thissystem was the upgrade of an existing BP oilrefinery works – which was already acustomer of Brisbane Water and using potablewater – to produce low sulphur fuels. Theupgrade was going to further increase thepressure on the potable supply andinfrastructure which was struggling to matchdemand from its existing resources.

A supply agreement between Brisbane CityCouncil and BP Ltd led to the development of the recycling system. The agreementdetails are:

• 20 years with a 10-year extension• Maximum 14 Ml/d expandable to 17 Ml/d• Take or pay price for the minimum demand• Lower price for excess demand• Guaranteed quality and quantity

The water is to be used for cooling tower,boiler feed and fire fighting. The qualityparameters are set at:

• Conductivity 60-120 µS/cm• pH 6.5-7.2• Turbidity <0.1 NTU• Free chlorine 0.3-0.5 mg/l

Process sequence is as follows (see Exhibit9.17):

• Prefiltration through Amiad 400 µm filter• MF through Pall (Microza) 6 x 66 elements

= 50 m2 at 0.1 µm with chlorinated backpulse and air scour

• MS filtrate tank• RO system is single pass, three stage:

° Stage 1 has 18 vessels (six elementsper vessel)

° Stage 2 has eight vessels

° Stage 3 has five vessels• Permeate storage consists of 2 x 6 Ml

covered storage ponds• Conditioning• To BP Ltd

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Exhibit 9.17 Process sequence at Luggage Point Wastewater Treatment Plant (courtesy Brisbane Water)

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The scheme in terms of the contract and thesupply has been a success but its operationhas led to the following observations:

• Location of valves and critical equipmenton the RO racks was not optimum withregards to access and height

• Chemical storage in relation to fumes andsunlight needs to be considered

• Pipe work failure on large section meantsignificant downtime during failures

• RO permeate is very aggressive soconsider materials carefully

• Free chlorine damages membranes• Variation of feed can overload the

pre-filtration so be conservative with thedesign, taking into account scum fromclarifiers, storm events, etc

• The design of the control system requirescareful thought to minimise effect of failures

• Scaling, design recovery of 85% notachieved

• Precipitation of calcium phosphate was a problem

• Trial plant needed to consider

° Scaling problems

° Bio-fouling

° Feedwater effect on product water• Need to add a lot of chlorine to reach

breakpoint chlorination if mono-chloramines are present

9.9 The Toowoomba experience with

public consultation

Toowoomba is a textbook example of howproposed IPR schemes become politicised.Toowoomba is an elevated, inland town inQueensland that does not have a local watersource. Supplies are pumped a great distancefrom dams to the east. Continuing droughthas depleted the levels in these dams,reducing available yields and promptingconsideration of alternative sources.

Toowoomba City Council(www.toowoomba.qld.gov.au) thereforeapplied for funding from the new ‘Water

Smart Australia‘ programme managed by theNWC, to implement an IPR scheme. Thescheme was to incorporate state-of-the-arttechnology, using MF/ultrafiltration, ROmembranes and UV advanced oxidation totreat high quality sewage effluent whichwould then be returned to the Cooby Dam via a chain of ponds, wetlands, boresand aquifers. The NWC endorsed theapplication and recommended approval to the Prime Minister.

Initially local politicians were supportive withpositive press briefings. From 1 July 2005 theproject was fully supported by all councillors,local state and federal MPs. However, withintwo months, following lobbying andopposition from local irrigators and propertydevelopers fearing negative publicity for thearea as well as the hastily formed ‘CitizensAgainst Drinking Sewage’ (CADS) group, thepolitical mood had changed and the fundingapproval stalled.

Significant funding – A$23 million (£9 million)in Commonwealth funding and a matching amount in state subsidy – was at stake. As away forward the NWC proposed areferendum, setting a new precedent inproject approval processes. Toowoomba CityCouncil opposed this approach as anabrogation of political leadership and usurpingthe democratically elected council’s mandatefor making decisions relating to itscommunity. It also felt that the alternativesthat were being proposed by politicalopponents (eg coal seam gas water) wereunfeasible and not correctly presented.

The run-up to the 29 July 2006 referendumwas a time of much activity, with a vocalnegative campaign and sensationalism in thetabloid press eg ‘Pull plug on poo water’ GoldCoast Sun, 5 October 2005 (see Exhibit 9.18).

The scheme supporters had difficulty ingetting the scientific arguments across. Waterutilities the world over watched with interest.

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The results of the referendum were 62%against and 38% for. Toowoomba City Councilis now facing a very uncertain future withrespect to water resources. If the droughtcontinues there is a real risk that water willbe unavailable. Level 5 restrictions currentlyapply, banning most outdoor water use.

Interestingly the Toowoomba experience didnot daunt other water providers fromfollowing the same path. A plebiscite hadbeen planned in South East Queensland for17 March 2007 to find out whether residentswere prepared to have recycled water in theirdrinking supply via the Wivenhoe Dam.However, on 29 January 2007 QueenslandPremier Peter Beattie said he had scrappedthe plebiscite, because due to the worseningdrought situation there was no longer achoice. He said that falling water levels hadleft his state administration with no optionbut to introduce recycled water in South EastQueensland, starting from next year.Although Australian PM John Howardsupported Mr Beattie’s comments, thepremiers of both South Australia and NewSouth Wales rejected the Queensland plan,prompting Malcolm Turnbull, the newenvironment and water resources minister, tocall for more open-mindedness on the issue.

As a result of the current drought situationand the interest in reuse, the Water ServicesAssociation of Australia (WSAA)(www.wsaa.asn.au) has recently published aposition paper on reuse, which is supportiveof IPR if appropriate decision-making andoperation criteria are followed.

NB The presentation to the mission wasgiven by Brisbane Water on behalf ofToowoomba City Council.

9.10 New Park Farm water mining

project

A three way owned plant between COPA,Brisbane Water and Brisbane City Council hasseen the development of a number of watermining projects (note the phrase ‘sewermining’ has been dropped to help with publicperception), including New Park Farm. Thesmall package plant and storage tank arelocated between established trees and so areunobtrusive (see Exhibit 9.19). However, thereare public information boards describing theprocess, the water quality, and how andwhen it is used.

Producing a Class A effluent (see Chapter 5)that is used to water a cricket field and park,the project was sited due to the proximity ofa large municipal (pressurised) main. Thisprovides the feed to the ReAqua MBR

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Exhibit 9.18 Examples of sensational press headlines(courtesy Brisbane Water)

Exhibit 9.19 New Farm Park water mining treatmentplant

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product. The MBR plant produces 25,000 l ofpermeate per day which is UV treated andchlorine dosed before storage from where itis collected by a tanker for irrigation.

There are a number of restrictions aboutwhen watering can be carried out, for healthand safety reasons and to optimise the returnon the water applied to vegetation.

9.11 Rocks Riverside Park water mining

project

Rocks Riverside Park water mining project is a large-footprint low-tech water reuse scheme– again ‘sewer mining’ has been replaced with ‘water mining’ to encourage publicacceptance of the process. The actual sitewas installed with a high degree of monitoringand telemetry as it is the first of its kind in theBrisbane region (see Exhibit 9.20).

The process is as follows (see Exhibit 9.21):

• Large septic tanks remove debris andlarger solids

• The septic tanks have a physical cartridgefilter on the outlet

• A pump regulates the flow to the first reedbed (horizontal)

• The effluent passes to a collectionchamber with the option to recirculate orpass on

• It then passes to the second reed bed (vertical)

• The system has a recirculation pump afterboth beds so if required (turbiditycontrolled) the effluent can be passed backto the head of the works

• The effluent is UV disinfected and passedinto a 300 kl storage tank

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Exhibit 9.20 Positioning of treatment plant and irrigated park at Rocks Riverside Park (courtesy Brisbane Water)

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The product water is used in the irrigation ofthe park and a tanker draw-off point isavailable. Tankers draw the water for irrigationand dust suppression.

9.12 SA Water and United Water

overview

SA Water, the South Australian watercorporation, is state owned and is required todeliver a dividend (95% of its surplus) to thestate on water/wastewater operations (seeExhibit 9.22). SA Water has awarded UnitedWater the operating contract for waterresource management, water treatment anddelivery and wastewater collection, treatmentand discharge in the Adelaide region.

United Water is now a partnership betweenVeolia Water (95%) and KBR (5%) and as well

as having responsibility for water andwastewater services in Adelaide is active inother parts of Australia and in New Zealand(see Exhibit 9.23).

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Exhibit 9.21 Rocks Riverside Park process (courtesy Brisbane Water)

Exhibit 9.22 A review of SA Water activities (courtesySA Water)

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South Australia is in the vanguard fordeveloping national water guidelines andregulations in Australia. SA Water leads thedevelopment of the National Guidelines forWater Recycling (see Section 9.13) and hasproduced use of rainwater guidelines. Thesehave been produced in co-operation with theEnvironmental Health Service of the SouthAustralia Department of Health.

The use of rainwater is strongly promoted inSouth Australia. The provision for collectionand use of rainwater has been compulsoryfor all new developments since July 2006.Rainwater must be used for at least one ofthe following: toilet flushing, laundry, the hotwater system.

There are differences of opinion on the use ofrainwater, especially whether or not it shouldbe used for drinking. Epidemiological studieshave concluded that it is safe and so can beused for consumption. This is a recognitionthat many people in rural areas havedepended satisfactorily on rainwater for theirwater supply as their only source of water formany years. They generally prefer to drinkrainwater rather than water from themunicipal supply.

The South Australian Health Authority isclosely involved in regulating water reuse and

rainwater schemes which have to beapproved, inspected and given permits.Incidents are monitored using prescriptiveincident criteria, and it is a requirement that20% of houses in recycling/rainwater useschemes have to be audited each year, ieeach house is required to be audited everyfive years.

The use of rainwater is clearly separated fromthe use of reclaimed water – grey, black orstormwater. It is difficult to justify that thereuse of greywater is economically viable.Stormwater run off from highways requiresspecific filter technology to ensure that it toocan be considered for reuse. The use oftreated stormwater for aquifer recharge andstorage is being evaluated.

There are tensions between the differentwater users in the region, especially withregard to historic abstractions for agriculture,including wineries, for which licences werenot required. Also, the newer garden suppliesbusinesses which provide plants for urbangardens provide a significant GDP for theregion. Evaporation from the Murray/Darlingbasin, from reservoirs and from the use ofpoor irrigation methods is a significant issueof concern. Other concerns include theallocation of water from the Murray/Darlingbasin – especially in drought situations,methods used for irrigation and the lack ofcontrol of discharges from septic tanks.

Politics, as much as water resource concerns,is driving the debate, with different issuesbeing promoted in different states. The WaterProofing Adelaide strategy (see Section 9.15)was made as an election promise.Consequently there are many opportunitiesfor the development and application ofdifferent water-related technologies to provide solutions for priority issues in thedifferent states.

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Exhibit 9.23 United Water activities (courtesy UnitedWater)

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In particular there are opportunities fortechnologies in:

• Secondary effluent polishing• Pipe identification for the prevention of

cross connections• Biomarkers• Cheap but quality monitors• Permeate treatment eg electrodialysis• Chlorine dosing control• Software for implementation and control of

recycled water schemes

The Cooperative Research Centre for WaterQuality and Health (see Section 9.14) is basedat and supported by SA Water.

9.13 Australia’s National Guidelines for

Water Recycling

A discussion with Dr David Cunliffe, PrincipalWater Quality Adviser, Department of Health,South Australia.

The first Australia-wide drought for 50 years hasstimulated moves to develop a National WaterManagement Strategy for both quality andquantity, with quantity (resources) being theprime and immediate concern. The AustralianNational Water Guidelines for municipal suppliesdo not include recycling or aquifer storage andrecovery guidance. Guidelines for rainwater usehave been developed following an A$1.2 million(£480,000) study on health issues around usingrainwater for drinking. It was noted that 90% ofrural properties have rainwater tanks and in80% of these properties the water is used fordrinking – legionella is not considered to be asignificant risk.

The Australian National Guidelines for WaterRecycling (Phase 1) were released on 27November 2006, following final approval by theMinisters of the Environment Protection andHeritage Council, and can be downloaded fromwww.ephc.gov.au/ephc/water_recycling.html.The development of the guidelines involvedthe Natural Resource Management Ministerial

Council, the Australian Health MinistersConference, a public comment phase and aninternational peer review.

The Phase 1 guidelines (subtitled ‘ManagingHealth and Environmental Risks’) focus on:

• Large-scale treated sewage and greywater for:

° Residential garden watering, car washing,toilet flushing and clothes washing

° Irrigation for urban recreational and openspace, and agriculture and horticulture

° Fire protection and fire fighting systems

° Industrial uses, including cooling water

• Greywater treated on-site (including inhigh-rise apartments and office blocks) foruse for garden watering, car washing,toilet flushing and clothes washing

Development of Phase 2 is under way and itsrelease for consultation is expected in mid-2007. This phase addresses:

• Use of recycled water for direct or indirectaugmentation of drinking water supplies

• Managed aquifer recharge for end usesincluding drinking water supply, non-drinkingpurposes and ecosystem protection

• Urban stormwater reuse

The 12-element risk management frameworkused to develop the Australian DrinkingWater Guidelines (2004) has been adapted tomanage risks to human health and theenvironment through the use of recycledwater. Safety is of paramount importance, sothe definition and public acceptance of ‘safe’is crucial to the acceptability, and hence use,of recycled water. The technical issues areaddressed as well as corporate commitment(especially employee training andawareness), communication, training andrelationships with other stakeholders andwith consumers. The comprehensive riskanalysis, planning and implementation of risk

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management measures, setting of criticaland operational limits, and appropriatemonitoring are all emphasised.

Human health risks from recycled water arisemainly from the presence of microbialpathogens but risks due to chemicals alsoneeded to be evaluated. The levels of a broadrange of pathogens must be reduced so thatexposure to recycled water does not pose anunacceptable health risk. Human health risksfrom chemicals in recycled water intended fornon-potable end uses are low, provided thatcontaminant management processes areeffective to minimise chemical input to thewastewater to be treated.

The guidelines have used quantitativemicrobial risk assessment (QMRA) to sethealth-based targets for pathogens in recycledwater treatment. This involves four steps:

• Hazard identification – including theselection of reference pathogens for eachmajor pathogen group – bacteria, protozoaand viruses

• Dose-response – the use of appropriatedose-response models for the referencepathogens

• Exposure assessment – estimates ofincidental ingestion during use for variousnon-drinking purposes, an allowance foraccidental cross-connections was factoredinto the calculations, but deliberate misuseof recycled water was not considered

• Risk characterisation – finally informationfor each reference pathogen was collatedand integrated to calculate the degree ofpathogen reduction required to meetspecific health-based target values

The QMRA values were set using themeasurement of health impacts in terms ofDisability Adjusted Life Years (DALYs) – theapproach used by the World HealthOrganization (WHO). This approach has theadvantages of taking into account theconsequences of infection as well as the

probability of infection. The average DALY foreach reference pathogen is averaged over thepopulation taking into account the frequency ofeach health outcome and considering all agegroups, but excluding specifically vulnerablegroups for which additional risk reduction maybe required and applied as needed.

The level of tolerable risk adopted is 10-6

DALYs per person per year which isconsistent with the values in the currentWHO Guidelines for Drinking-water Quality.The level equates to an annual risk of onecase of diarrhoeal illness among 1,000 usersof recycled water; the background risk is 800-900 cases per year from all sources.Using this, along with data on occurrence ofpathogens in raw sewage and humanexposure rates, the degree of pathogenremoval necessary to produce recycled waterof suitable quality can be calculated. Virusesrequire a larger degree of reduction thanother classes of pathogens.

The development of DALYs for microbialproblems is more straightforward than forchemicals. The modification of individualbehaviours and choice of household productsvia education is important. The chemical risksare not dissimilar to those for drinking water,although EDRs, pharmaceuticals andcomplex mixtures do need to be factored into the assessments.

The highest exposure category considered inthe guidelines is firefighting, with domesticnon-potable uses involving a slightly lowerlevel of exposure. Health risks from use ofrecycled water in non-domestic situations canalso be managed and minimised by theimplementation of preventive measures atthe point of use.

Public perception is that greywater has a lowlevel of risk, but microbiological quality ofgreywater is highly variable and levels offaecal indicator organisms can approachthose in sewage. Due to the small scale of

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most greywater recycling schemes pathogentesting is limited to monitoring for E. coli toassess the amount of faecal contamination.Continuing education of residents is neededto minimise contamination levels and for on-site greywater systems serving singledomestic dwellings less stringentmanagement processes are appropriate,especially the avoidance of cross-connectionsto public drinking water supplies.

There was general public acceptability of theuse of recycled water complying with Phase 1guidelines as shown by the number ofdevelopments under construction incorporatingthe delivery and use of recycled water.Invariably there were stringent monitoringprogrammes being conducted to evaluate theeffectiveness of the guidelines in ensuring thesafe delivery and use of recycled water.

The Australian National Guidelines for WaterRecycling (Phase 1) can be downloaded from:www.ephc.gov.au/ephc/water_recycling.html

9.14 Cooperative Research Centre (CRC)

for Water Quality and Treatment

The CRC for Water Quality and Treatment isAustralia’s national drinking water researchcentre, linking public health research withwater quality expertise. It was established in1995, with funding until 2008, and providesintegrated ‘from catchment to tap’ researchand knowledge management programmes tosupport the Australian water industry.

The CRC is an unincorporated joint venture of29 full members including CSIRO, universities,research users and associates (mostly SMEs).It involves 90% of the Australian waterindustry. Some 230 researchers have beeninvolved with a total of A$153.1 million (£62 million) cash and in-kind to June 2008. A full spectrum of disciplines has beenstudied, including epidemiology, engineering,microbiology, toxicology and water treatmenttechnology. The three major programmes have

covered health and aesthetics, ‘catchment tocustomer’ and policy, regulation andstakeholder involvement.

Broad achievements include gaining a stronginternational reputation for public watersupply research – with a leadership positionin some areas. Major revisions to theAustralian Drinking Water Guidelines wereimplemented and the framework wasadopted by the WHO and the EuropeanCommunity. Substantial knowledge gains incatchment management, source waterprotection, management of storages,treatment technologies and distributionsystem management were achieved. A review of the CRC stated that outcomesare saving the Australian water industry A$26 million (£10 million) per year intreatment and management costs.

To follow on from the CRC, ‘Water QualityAustralia’ (WQA) has been proposed. Aninitial proposal was developed jointly by theWater Services Association of Australia(WSAA) and the CRC in Water Quality andTreatment seeking initial commitment frompotential participants. Core participants willbe Australian water utilities, researchorganisations (eg CSIRO and universities),private sector companies, consultants, state and territory health regulators andwater resources managers. There will also be an option for smaller operators,private companies, consultants and other organisations to participate asassociate members with restrictedparticipation in the centre management butwith full access to research outcomes fromthe core programmes.

Industry participants will pay annual cashcontributions and in-kind support for projectssuch as access to facilities, provision of dataand technology transfer. Research providerswill be required to provide agreed amounts ofin-kind support through the provision offacilities, and the time of staff administering,

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supervising and undertaking research. Topicsto be covered include:

• Public health – pathogens, epidemiology,toxicology

• Water harvesting – catchments, reservoirs• Water delivery – water treatment,

distribution systems, monitoring, riskassessment

• Water recycling – water reuse, wastewater

Social science research will be outsourced,especially that related to the acceptance ofrecycled water.

The WQA will continue the successfuleducation and training programme from theCRC. The focus will be on supporting andtraining PhD students, with directinvolvement by industry encouraged,including joint supervision and provision ofwork experience. It is proposed that WQAwill become fully operational in July 2008 totake over from the CRC.

9.15 Water Proofing Adelaide

The Water Proofing Adelaide initiative wasstarted in October 2003 to produce a strategyfor management, conservation anddevelopment of the city’s water resources upto 2025 (www.waterproofingadelaide.sa.gov.au/main/). The strategy has been developed withthe South Australian state government seekingto engage the community in making decisions.SA Water is the government company thatserves the whole state. The company has1,300 employees with A$6 billion (£2.4 billion)of assets, including 20 water and 23wastewater treatment plants. Water utilitiesservices in Adelaide are delivered throughUnited Water, which is 95% owned by Veolia.

Current mains water supply in Adelaide isapproximately 200 Gl/y and is anticipated to rise to 240 Gl/y by 2025. On top of this 100 Gl/y is extracted and used for irrigation.Residential usage (58% of total) accounts for

the majority of the latter. Typical suburbanhouseholds use 284 kl/y of mains water(2002/03 figures) with 40% used outdoorsand on the garden: this is obviouslydependent on the weather (see Exhibit 9.24).

The Water Proofing Adelaide strategy is three-pronged in approach:

• Managing existing resources• Responsible water use• Additional water supplies

Management of existing resources includedbetter management of Murray River supplies,the introduction of planning controls in theMount Lofty Ranges, which surroundAdelaide, and control of septic tankdischarges in this region. Groundwatersources in the northern Adelaide plains willalso be exploited.

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Exhibit 9.24 Average household water use in Adelaide(courtesy SA Water)

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For responsible water use, there were threekey ‘education’ planks:

• Information about Water Proofing Adelaidein general and specific strategies (egrecycled water, pricing decisions)

• Community engagement to ensure quickacceptance of strategies such as SmartWater Mark

• Long-term behaviour change strategies tobring about a lasting shift in how thecommunity manages water use

In the home, major savings from initiativesalready in place include using low-flowshower heads, replacing twin-tub washingmachines with low water usage front-loadingmachines and dual-flush toilets. In addition tothese three measures, further savings arepredicted from the proposed educationprogramme that also includes shower timersand flow limiters on taps.

Further water saving initiatives include:

• Water Efficiency Labelling scheme fordomestic appliances and fittings

• Smart Water Mark for water-efficientgardens

• Eco-Smart plumbers• Partnership with the Nursery and Garden

Industry Association

• Water efficiency audits for commercial,industrial and community areas

• Partnership with Business SA for seminarsand workshops on water efficiency and conservation

• Turf industry group and code of practice forirrigation of open spaces

• Education programme

SA Water currently recycles 20% of theavailable treated effluent through two majorschemes. The Virginia Pipeline Scheme to thenorth of the city is one of the largestwastewater reuse schemes in the SouthernHemisphere and supplies >20,000 Ml/y tomarket gardens (See Section 9.17). It isproposed to increase the amount of treatedeffluent reuse to between 40 and 57%.

Additional water supplies are to be providedfrom mandatory rainwater tanks (arequirement on all new properties) in additionto the reuse schemes and stormwatercollection. From SA Water’s analysis, dualreticulation (third pipe) is more economic thanrainwater collection (see Exhibit 9.25).

A seawater desalination policy is beingdeveloped but there are no immediate plansfor its introduction. Other policy changes beinginvestigated are aquifer storage and recharge.

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Issue Third pipe (Mawson Lakes) Rainwater tank

Per property comparison

Capex cost On property A$1,000 (£400) A$2,000 (£800)

Subdivision A$2,000 (£800)

Treatment/transfer A$2,000 (£800)

Total capex per property A$5,000 (£2,000) A$2,000 (£800)

Re-use potential (kl/y) 200 20

Capex (A$/kl) 23 (£9/kl) 100 (£40/kl)

Saving SA Water infrastructure Yes No

Saving River Murray resource Yes Yes

Saving RM licence (drought year) Yes? Part

Exhibit 9.25 Cost of household rainwater collection compared with dual reticulation (courtesy SA Water)

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It is worthy of note that from Water ProofingAdelaide’s analysis, water provision from theMurray-Darling Basin for irrigation is worthmore in A$ earned per Ml used comparedwith other parts of south eastern Australia.When assessing a range of options for newwater, the least-cost option was to purchasefurther River Murray licences; it also providedthe highest water volumes. However, this wasreckoned to be the least sustainable option.

9.16 Mawson Lakes water recycling

and dual reticulation scheme

Mawson Lakes is a new development nearAdelaide which has a dual reticulation system.The system is a joint development by SA Water(see Section 9.12) and the City of Salisbury(www.mawsonlakes.com.au). SA Water nowowns and operates the system through thecontracted operating company United Water. Theproject had an estimated capital cost of A$16million (£6.4 million). When completed in 2010 itwill have 4,300 dwellings accommodating11,000 residents with a commercial centre andschools. The reclaimed water is used for toiletflushing, domestic and public irrigation and carwashing (see Exhibit 9.26).

The initiative took some time to come tofruition, the original concept of completelydecentralised reclaimed water provision beingrevised when reclaimed water became availablefrom the large sewage treatment works nearbyat Bolivar. Ownership and operation also tooksome time to agree upon. The system also usesstormwater, which has the benefit of beinglower in salinity than the reclaimed effluent. Thesystem follows Australian convention withpurple pipes and fittings for the reclaimed waternetwork to minimise the risk of crossconnection (see Exhibit 9.28).

The treatment process to provide thereclaimed water reflects the same approach torisk mitigation. Bolivar Sewage TreatmentWorks has conventional activated sludge plus avery large tertiary lagoon system. The tertiary

effluent then undergoes DAFF treatment andis chlorinated to achieve a minimum Ct of 60 mg.min/l, providing a five-log removal ofprotozoa and six-log removal of virus. Thestormwater source undergoes treatment in an extensive, award-winning urban reed-bedsystem and is chlorinated (see Exhibit 9.27). Asophisticated control system ensures anappropriate TDS (<900) from the effluent andstormwater, blending with potable water ifnecessary. The system automatically shutsdown if predetermined quality criteria for thesources are not met (for reclaimed wastewaterif Ct<60 mg.min/l for 60 minutes and forreclaimed stormwater if free Cl2<0.2 mg/l for30 minutes).

Management of the system involvedattention to similar risk issues as other dualreticulation schemes, both in Australia andelsewhere. Detailed risk assessments wereundertaken and a multi-barrier approach torisk treatment was adopted. Operationalregimes included standby power provision,lower recycled water operating pressures andrecycled and potable meters being different inlength, thread and colour. Extensivecommunity consultation was undertaken.

When the system operation was transferredto United Water, problems with the integrityof the network were identified, such asinstances where the internal plumbing hadbeen connected to the reclaimed system in error. This highlighted the necessity for pre-commissioning audits on all propertiesfrom main to meter and including internalplumbing. This took three months. It alsoresulted in the development of a new five-stage, pre-commissioning audit process forfuture developments.

United Water pointed out that the cost ofpolicing and monitoring a dual reticulationscheme should not be underestimated. Forexample, separate 99-year contracts had tobe agreed with every home owner. Specialtraining for personnel was undertaken,

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detailed contingency plans developed and adetailed plumbers’ guide prepared. A waterquality monitoring programme was developedand incident reporting protocols agreed. Theview was that recycled water systems arehigh risk (albeit that the risk can bemanaged), and that risk management is anongoing responsibility, ie it does not end oncea system has been commissioned.

9.17 Bolivar/Virginia reuse scheme

The Bolivar Sewage Treatment Works is hometo a large effluent reuse scheme. Sewageeffluent is treated to Class A standard andpassed to agricultural customers for irrigation.

The sewage treatment plant

The sewage treatment plant is theamalgamation of two treatment works:

• A new sequencing batch reactor was built to receive high salinity flows, but thehigh salinity effluent is not passed on to be recycled

• A conventional activated sludge systemfeeds the recycling works

The AS system is approximately one millionPE in size. The effluent is fed into a series of

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Exhibit 9.26 Mawson Lakes water systems (courtesy SA Water and United Water)

Exhibit 9.27 Covered reedbed for stormwaterreclamation

Exhibit 9.28 Standard pipe colour coding in BolivarSewage Treatment Works

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lagoons which provide a barrier forcryptosporidium – 16 days retention arerequired to satisfy the regulatoryrequirement. However, 50% of the lagoonsare currently not in operation as there arepersistent mosquito problems.

The recycling plant

The lagoons, while reducing suspendedsolids and deactivating cryptosporidium, cancause problems with algal blooms;consequently the effluent is fed to adissolved air filtration system combiningflotation and depth filtration. Alum andpolyelectrolyte are dosed in a standardcoagulation/flocculation arrangement. Theplant uses 10-15% of inlet flow in wash waterwhich is then passed to the head of thesewage treatment system. The plantproduces 70-100 Ml/d and has 200 Mlstorage. The recycled effluent is required tomeet the following standards:

• Cryptosporidium – 0• Turbidity – 10 NTU• E. coli < 10 cfu/100 ml• 2 mg/l free chlorine

9.18 Melbourne,Victoria and SE Water

The discussions covered sustainable waterand supply demand strategy, water recycling,centralised greywater recycling, stormwaterreuse and environmental and health riskmanagement.

A 33% population growth is expected by2056. The area is also susceptible to bushfires. Declining aquifers (23% over the lastfew years), degradation of river systems,increasing land use and housing growth haveprovided the impetus to formulatingsustainable water policies. The first WaterPlan (1995) is currently being updated.

Reducing the amount of water use (savingwater) is one way to protect the state’s water

supplies; another is through collecting andrecycling alternative water sources such asrainwater, stormwater, greywater andsewage. Increasingly people are interested in,or are already using, alternatives such asrainwater tanks and reusing laundry water onthe garden.

The White Paper Our Water Our Futurecharged EPA Victoria and the Department ofHuman Services with the task of reviewingthe public health and environmentalframework for the use of alternative urbanwater supplies.

The state government has released adiscussion paper, A Framework for AlternativeUrban Water Supplies, which presents theresults of the review. The paper looks at howalternative water supplies can be used, safelyand sustainably.

In March and April 2006, public consultationsessions were held in Melbourne andregional centres across Victoria, as part of thefeedback process. The result is now informingthe regulatory framework supporting the safeand sustainable use of rainwater, stormwater,greywater and recycled sewage effluent. Therisk (water safety) approach is being adoptedand there is a five-year economic plan agreedwith the economic regulator.

Greywater (all non-toilet householdwastewater) can be a good water resourceduring times of drought and waterrestrictions, but its reuse can carry health andenvironmental risks. The EPA believes thatgreywater can be reused effectively andsafely in domestic situations. It was notedthat before supply commences that theHealth and Environmental Management Plan(HEMP) based on HACCP must be agreedwith the user.

There is also significant interest in using tankersto supply reclaimed water (water from sewagetreatment plants), reflecting the increasing

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restrictions on water resource. Reclaimed waterprovides a defined quantity and quality of waterthat, with controls, is suitable for a wide rangeof uses. The majority of reclaimed water useincludes dust suppression, watering councilparks, gardens and agricultural irrigation such asfor cattle grazing.

Incentives for using recycled water include:

• Rising block tariff structure• Pegging recycled water at the price of the

lowest of a three-tier charging system

Incentives for households to economise onmains water use include:

• Exchange of shower heads• Changing top loading washing machines• Purchasing and installing a rainwater tank

(up to A$1,000 (£400) for a 5,000 l tankconnected to toilet and laundry)

It is assumed that rainwater tanks can saveup to 40,000 l/y per household. However, SEWater has some concerns regarding thecollection and use of rainwater as it reducesits market for recycling water. Interestinglyestate agents are not keen on rainwater tanksbecause they look ugly and take up space!

All new builds are expected to have dualreticulation as well as rainwater tanks. As inother states there is a star rating system fornew builds to encourage uptake of energyand water-efficient designs and equipment –having solar heating, recycling or a rainwatertank qualifies for a 5* rating and having twoqualifies for a 6* rating.

It has been estimated that the cost ofretrofitting is four times that of a ‘new build’,while use of reclaimed water costs 15 timesand stormwater six times as much as potablewater. Hence there is a considerable subsidy,which is justified as it does encourage thesustainable and efficient use of water.

9.19 Inkerman Oasis residential

development

Inkerman Oasis is the result of a projectfunded from the CommonwealthGovernment’s Living Cities Urban StormwaterInitiative. It incorporates the development of amulti-story residential apartment block in oneof Melbourne’s outer suburbs. It is apioneering venture for Victoria as it is the firstgreywater recycling system of its type to beinstalled in a high-rise residential setting. Thecurrent development consists of 100apartments, but will ultimately increase to236 apartments.

The recycling process

The greywater treatment site is installedwithin the centre of the development and hasbeen made a feature within the general WaterSensitive Urban Design (WSUD). Exhibits9.29 and 9.30 show the location of the plantwith respect to the development highlightingits close proximity to the central footpath.

Treatment train

Pipework diverts greywater from bathroomwashbasins, baths and showers to a commonholding tank. The roof rainwater is collected

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Exhibit 9.29 Siting of the recycling plant withinInkerman Oasis residential development

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and passes by sub-surface flow through aconstructed wetland (see Exhibit 9.31) withinthe development, it is blended with thegreywater before entering a membranebioreactor using MF membranes. After bio-filtration the treated water is fed to a secondunderground holding tank which provides bufferstorage and further treatment through UV disinfection. Exhibit 9.32 depicts the processschematic for the recycled water system.

9.20 The Urban Workshop

The Urban Workshop is a 33-storey modernmunicipal building which contains agreywater/blackwater recycling plant. Thepipework and structures were incorporatedduring construction of the building and theplant itself was installed in a small dedicatedsection of the underground car park (seeExhibit 9.33).

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Exhibit 9.30 External design features of the recyclingplant at Inkerman Oasis

Exhibit 9.31 Constructed wetland across the path fromthe treatment plant

Exhibit 9.32 Process schematic for the Inkerman Oasis treatment plant (courtesy South East Water)

UVdisinfect

Establish targetconcentrationswith end-useexposures andpathogeninfectivity

Microfiltrationmembranebioreactor

Storagetank

95%ile ofpathogenconcentrations

Log removal target

Inkerman Oasis• Approximately 3.5 log virus reduction• Approximately 1 log protozoan reduction

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The plant is a standard inbuilt MBR systemwhich recycles greywater and blackwater fortoilet flushing. It operates as a closed loopuntil the salinity reaches a set point at whichthe contents are flushed away to themunicipal sewer and the cycle starts again.

The process consists of a 2 mm screen, abalance tank and an aeration tank with asidestream MBR unit. The product water isdisinfected using chlorine and UV.

The contractor, Walter J Pratt, received theAnnual Plumbing IndustryCommercial/Industrial Project of the YearAward 2006 for the project, based onmeasured water use reductions over currentplumbing systems using new technology andinnovation. The project was the firstblackwater treatment plant commissioned inAustralia in a multi-storey building.

9.21 Royal Park Wetlands Stormwater

Treatment and Reuse System

In 1998 a development plan was produced forthe Royal Park in Melbourne which, althoughinitially it did not contain a stormwaterrecycling scheme, was modified to include apark wetlands system for stormwaterrecycling. The main driver for this late insertionwas the Commonwealth Games of 2006.

The wetlands scheme

Launched officially in June 2006, the urbanwetland has been designed to treatstormwater runoff from roads, rooftops andgutters from surrounding suburbs to provide ahabitat for wildlife and to deliver recycledwater for use in the park.

The wetland consists of two linked ponds. The‘treatment wetland’ (see Exhibit 9.34) acts asa natural filter with banks densely covered bynative Australian plants that treat and cleanstormwater through natural biologicalprocesses. The processed water then goes tothe ‘storage wetland’ before being disinfectedand used to irrigate the park in summer.Excess flows are fed directly to Port PhilipBay. Exhibit 9.35 highlights the features of the treatment system with associated flow volume.

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Exhibit 9.33 Plant position in a dedicated section ofthe car park at the Urban Workshop

Exhibit 9.34 Royal Park wetland treatment pond

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Exhibit 9.35 Royal Park Wetlands Stormwater Treatment and Reuse System process schematic (courtesy City of Melbourne)

WATERSOURCES

TREATMENTAND STORAGESYSTEMS

DISTRIBUTIONSYSTEMS

IrrigationEND USE

Stormwaterrunoff

Rainwater

UVdisinfection

Constructed surfaceflow wetland

Storagepond

Sedimentationbasin and diversion

PumpingBuffertanks

200 m3

(two tanks of 100 m3)

187 ha438 Ml/y

Main drain55 Ml/y

Main drain365 Ml/y

Up to 1 m3/ssubmergedinlet

8,000 m2

surface area0.5 mextendeddetention3,000 m3

permanentpool

1.2 ha pondmin volume6Ml; maxvolume 18Ml

10 l/s fromstorage pond

383 Ml/y

74 Ml/y being suppliedby 24 l/s pump

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