Managed Aquifer Recharge

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Mike Dudding mdudding@skm.com.au ph 9248 3375

Rob Molloy rmolloy@skm.com.au ph 9248 3467

Applications for MAR

> 1. Water storage

> 2. Reduce evaporation

> 3. Water treatment (mainly micro-biological contaminants)

> 4. Reduce stormwater runoff (WSUD)

> 5. Increase stream baseflow (WSUD)

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3

Injection wells (ASR)

-70

-60

-50

-40

-30

-20

-10

0

10

20

30

-500 -400 -300 -200 -100 0 100 200 300 400 500

Distance from middle injection bore normal to wellfield axis (m)

Dep

th (m

)

Initial groundwater pressure

Injection bore

Groundwater pressure at end of injection period

Shallow aquifer

Aquitard

Target aquifer system

Ground surface

Mixed injected water and native groundwater too salty for re-use

100% injected water

Decreasing potential for upward leakageInterface between native groundwater and the injected

water/native groundwater mixture

Mixed injected water and native groundwater OK

for re-use

MAR Systems(1)

MAR Systems (2)

MAR in urban water management

urban planning

water supplywastewater

management

Storm water management

MAR

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Gold Coast ASR

Upper Nepean ASRParamatta Rail Link AR

Yarram ASR

Broken Hill ASR

Alice Spring SAT

Beenyup ASR

Melb ASR MapRossdale ASRMernda ASRMelbourne Water ASRKoo Wee Rup Waste Injection

Neuarper - Apsley ASR

Barwon Downs ASRAnglesea ASRBlack Rock ASR

Warnambool ASR

Angas - Bremer ASRTorrens Linear Park ASRAdelaide Botanical GardensMcLaren Vale ASRCity of Salisbury ASR

SKM Australian MAR ProjectsGold Coast ASR

Three Principles for Successful MAR

> 1. Must have a demand for the water

> 2. Must have a water source

> 3. Must have a suitable aquifer

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Hydrogeological provinces

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Cross Section – Essendon to Western Port

Melbourne City

ASR Broad Scale Map – ASR potential

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Annual Usage

>200 ML

100 to 200 ML

20 to 100 ML

10 to 20 ML

ASR Broad Scale Map

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MAR for SE Water

> Best Region in Melb for MARo Good availability of source water (stormwater or treated)o Aquifers relatively shallow

> MAR Strategyo Multiple Small to Med scale schemes (<100 ML/year)o Limited capacity for large schemes

• Options include KWR area, and SETP/Frankston area

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Rossdale ASR

> Demonstration project

> Injection trials completed

> Currently operating under temporary licence

> 10 ML/year scheme

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ASR Investigations at Rossdale GC, Melbourne

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Rossdale Control Panel and Headworks

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MAR Project Stages

Stage 0 – Opportunity Assessment» Where is MAR needed (ie sites of supply and demand)?

Stage 1 - Feasibility Assessment» Desk top and/or limited field investigation

Stage 2 – Investigation» Aquifer Exploration, Hydraulic Testing, Sampling,

Environmental Assessment, Regulatory Issues

Stage 3 – Conceptual Design» Numerical Modelling (usually large scheme only)

Stage 4 – Functional Design» Injection and Recovery Trials

Stage 5 – Detailed Design

For small schemes there usually less stages

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Typical Investigation for Small Scale Scheme> Stage 1: Feasibility and nvestigation

• Identify water source and volumes (opportunity assessment)• Search for bore data from nearby bores (often not available)• Drill one investigation bore (suitable for injection trial)• Short flow test (24 hrs) and water quality sampling• Scope out and cost injection and recovery trial• Commence regulatory approvals• Preliminary design and cost estimate

> Stage 2: Design• Detailed design of connection to water source and demand• Connect site to source water and demand• Conduct injection and recovery trial (up to 1 week if possible)• Finalise design• Submit design for regulatory approval

> Stage 3: Commission Site

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Typical Costs for Small Schemes (<100 ML/y)

> Stage 1: Feasibility and Investigation• ~$150k

> Stage 2: Design• ~$150k for small scale schemes (<100 ML/year)

> Stage 3: Commission Site• $50k to $100k

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MAR Economics

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Cost for alternatives

> Water Cartageo $30 to $40/kL

> Underground Storage Tankso $20 to $40/kL

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Risk v Cost

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Ris

k

Cost

Underground storage tanks

Water cartage

MAR

Typical ASR bore layout

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Key Benefits

> MAR provides storage where land costs are high or is not available (ideal in urban setting)

> Meets challenge of climate change (ie need for urban storages)

> Compatible with Water Sensitive Urban Design

> Costs are comparable with current urban supply

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ASR Investigations on Gold Coast

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ASR Investigations on Gold Coast

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Guidelines

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Victorian technical guidelines for MARwww.smartwater.com.au

National Guidelines have just been released for commentwww.ephc.gov.au/ephc/water_recycling.html