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Think Tank

16 April 2024

biik wurddha, Sunbury, Wurundjeri Woi Wurrung Country

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Acknowledgement of Country

Greater Western Water respectfully acknowledge the Traditional Owners of the lands and waters upon which we work, operate and rely, the people of the Kulin nations.

The Greater Western Water region covers Bunurong, Djaara, Taungurung, Wadawurrung and Wurundjeri/Woi Wurrung Country.

We pay our deepest respects to their Elders, past and present. We acknowledge the continued cultural, social and spiritual connections that First Nations people have with the lands and waters and recognise and value that the Traditional Owner groups have cared for and protected them for thousands of generations.

We will further develop our partnership with the Traditional Owner groups to ensure their contributions to the future of the water management landscape and to maintain their cultural and spiritual connections.

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Agenda

Acknowledgement of Country
The water industry context
GWW Context

Customer voice – What we have heard?

GWW Service Area – Our Entitlements
The Macedon Ranges
Garden Hut Reservoir
Return of entitlements to Traditional Owners and the environment.

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Our challenge as a sector

2070

Population: 12.7 Million

2030

Population: 6.3 Million

2050

Population: 9.5 Million

Increasing urbanisation will create more sewage and stormwater to be managed

Victoria will be warmer and drier

There will be less water in our rivers

There will be more extreme events that pose risk to our water supply

We are facing considerable water challenges over the next 50 years

We are going to need a lot more water – across Greater Melbourne we are already using more water than naturally flows into our water storages
Population is growing – more than double in next 50 years. Western region is the fastest growing region in Victoria.

Over the next 50 years the number of GWW customers will double from 1.4m to 3m people

This means increased urbanisation – creating more seage and stormwater our system must manage and safely reuse or return to the environment.
Our drying climate means less water is flowing in our rivers and captured in our storages.

We have already seen climate change impacts on our dam inflows from 1997 until the present.

Beyond consumptive water requirements, we also need to provide more water for the environment to protect the health of our already stressed waterways and the ecosystems that depend on them.
We are also committed to supporting the Victorian Government in returning water to Traditional Owners to support their cultural needs and values

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GWW Context

Key statistics for our service area

$3.7 billion infrastructure asset base
20 large dams
7 water filtration plants
10 recycled water plants
7,500km of water mains
6,400km of sewer mains
115,000ML/year of drinking water consumption
108,000ML/year of sewage managed
22,230 recycled water customers
6,377ML year of recycled water supplied

As a water corporation our role is to provide the Greater Western region with safe and secure access to water supply and sewerage services.

2023 FY	Drinking Water (Potable + local supply)		Recycled & Storm Water
2023 FY	Volume (ML)	Customer Numbers	Volume (ML)	Customer Numbers
Central (CWW)	112,214 (86%)	527,119 (86%)	2,256 (37%)	15,465 (73%)
Western (WW)	18,132 (14%)	88,500 (14%)	3,778 (63%)	5,725 (27%)
Total	130,346	615,619	6,034	21,190

Our region is across an area of 3,700 square kilometers, stretching from Melbourne’s central business district (CBD), inner and north-western suburbs through the Melton and Sunbury growth corridors to Bacchus Marsh and the Macedon Ranges.
We provide drinking water, recycled water, sewerage and trade waste services to

approximately 568,000 residential customers

and more than 47,000 non-residential customers.

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GWW Context

‘What we heard from customers’

Recent engagement through our pricing submission ensured we reached all areas of our diverse community. We heard that our customers and community want:

affordable and stable bills.
us to support the health of waterways and the environment.
everyone to have access to the same quality and consistency of water, wherever they live.
us to make sure unplanned disruptions don’t increase, and to better inform them when they do happen.
want us to increase our uses of alternative water, such as fit for purpose recycled water and stormwater.

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Our entitlements – ‘Rights to water’

Western Region:

Lancefield
Macedon and Mount Macedon
Maribyrnong
Myrniong
Riddells Creek
Romsey
Woodend
Gisborne
Werribee

Northern Victoria:

Goulburn
Murray

Greater Yarra Thomson System

Desalinated Water Entitlement

Bulk entitlements and environment entitlements are legal rights to water granted by the Minister for Water under the Water Act 1989.

They provide the right to take or store a volume of water subject to a range of conditions

Bulk entitlements are held by specified authorities, such as water corporations

Environmental entitlements are held by the Victorian Environmental Water Holder.

GWW hold entitlements from:

Greater Yarra Thomson System (greater Melb Pool) – (up to 171,047ML and based on % water available of a total of 615,104ML system entitlement share)

Desalinated Water (Vic Desal Plant) - (up to 39,595ML annually – and proportionally to the annual desal order)

9 systems in the western region – based historically we have taken water from local systems as it was based on townships.

Before Millenium drought really relied on local surface water and groundwater –

Since Millenium drought connected to Melbourne Syste

And with growth of region – progressing plans to bring more water in from outside catchment

connect to these townships to broader Melbourne system

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Romsey/Lancefield Context

Operating in flow stressed Maribyrnong/Mirrangbamurn catchment

Upper Deep Creek (Reach 1) environmental shortfall 6.2GL/yr

Water security challenge

Lancefield & Romsey potable water demand will increase from 700ML/yr to 1270ML/yr in the next 50 years

Lancefield - 210ML/yr to 400ML/yr
Romsey – 490ML/yr to 870ML/yr

Garden Hut�Vol: 46ML

Kerrie

Vol: 297ML

Forster�Vol: 18ML

Wright�Vol: 55ML

Upper Deep Creek

Lancefield

Romsey

Bore

120ML/yr

33ML/yr

63ML/yr

445ML/yr

0ML/yr

48ML/yr

Note – Reference Volumes in FY2023

Lancefield WFP

Romsey WFP

From Rosslynne System

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Garden Hut

Garden Hut Reservoir is a GWW asset.
Onstream storage with a capacity of 46 ML
Historic info
Current management

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Questions put Think Tank prepared:�

Are environmental values considered in reservoir management ? How?

2. Are creek flows measured? How?

3. Are there minimum reservoir levels to be met?

4. Can a passing flows and minimum level for Garden Hut Creek be introduced?

5. What are the future plans for the reservoirs and creeks in the catchment?

Are environmental values considered in reservoir management ? How?

Creek will have periods of drying out and wet

Passing flow requirements are not on the reservoir but on the creek but not the creek feeding Garden Hut

Downstream of Garden Hut at Monument Creek – noting we haven’t taken water from this creek as due to operating arrangements and climate

2. Are creek flows measured? How?

Gauged – we have a Bulk Entitlement monitoring and reporting process with DEECA

3. Are there minimum reservoir levels to be met?

GWW have an Annual Operating Plan

4. Can a passing flows and minimum level for Garden Hut Creek be introduced?

Bulk entitlement are issued by the Minister for Water under the Water Act.

5. What are the future plans for the reservoirs and creeks in the catchment?

Long term integrated water cycle mass balance project investigating future of water cycle in our region

Next section talks to the return of water to TOs and the environment

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Returning Bulk Entitlements to Traditional Owners and the environment

Central and Gippsland Region Sustainable Water Strategy (CGRSWS) and Water is Life, Traditional Owner Access to Water Roadmap

biik wurddha, Sunbury,

Wurundjeri Woi Wurrung Country

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Returning water to Traditional Owners and the environment

GWW is committed to partnering with Traditional Owners and the environment to deliver on commitments in:

Central and Gippsland Region Sustainable Water Strategy
Water is Life – Traditional Owner Access to Water Roadmap
Greater Melbourne Urban Water & System Strategy
GWW’s Reconciliation Action Plan and GWW 2030 Strategy.

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Commitment to consider how river entitlements can be reduced via water efficiency, IWM and substitution with manufactured water sources

“

- CGRSWS Action 4.2

”

Lower reaches of Wirribi Yaluk, Bunurong and Wadawurrung Country

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2023 Proposal Options

We have four options that could result in the return of approximately 3.7GL of river entitlements (Rosslynne, Lancefield, Romsey, Barringo Creek and Werribee) in total.
All four options require further investigation through feasibility assessment.
Options 1 and 2 could require additional water from the Greater Yarra System Thomson River Pool to service demand.
Options 3 and 4 would not have water security impacts but may have operational risks.
GWW will continue to investigate water return opportunities in our other systems.

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Djerriwarrh Reservoir, Wurrundjeri Woi Wurrung Country

We are working closely w MW, Wurundjeri Woi Wurrung, CGRSWS Traditional Owner Partnership and DEECA to progress these investigations.
GWW will also be closely involved in the update of MW's Flow Recommendations project throughout 2024 and the findings/recommendations from this work will support our feasibility assessment.

GWW will be conducting a feasibility assessment and technical investigations to ensure these returns do not impact our water security and to understand the risks and impacts to our existing operatoins.

Investigations into:

Infrastructure works required.

Risks/impacts to existing GWW operations.

Updated modelling and data on catchment yields and water security position.

Catchment behaviour and water quality.

Assessment of:

CGRSWS quadruple bottom line approach and cultural benefits framework.

Risks to GWW water security and greater Melbourne region.

Potential impacts to other water users (e.g downstream users).

Potential impacts to the environment.

Next steps

This is only the internal analysis.

Engagement is to come and that is the crucial part to return water in a way that is meaningful and self-determined.

Volume 3.7GL is entitlement volume

Yield – not certain due to climate, how system operates

Option 1 Rosslyne, Option 2 - Lancefield & Romsey together (974ML entitlement return which is approx. half), Option 3 - Barringo (unused entitlement 585ML), Option 4 - Werribee Entitlement

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Questions?

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Legend

Pipeline

Waterway

Channel

Flow direction

Not in use

Metering and compliance point schematic

WSE000115 – Consolidated Bulk Entitlement (Lancefield) Conversion Order 2001 as at 8 Sept 2022

Not to scale

Storage

Weir

Stream flow gauge

Depth gauge

Flow meter

Pump station

Water treatment plant

Population centre

Specified point

Compliance point

Site telemetry

Garden Hut

Lancefield Basin

Garden Hut Creek

Monument Creek

Bore Supply

SP-LA-01

CP-LA-02

SP-LA-03

SP-LA-02

Lancefield

Service By Agreement

Lancefield WTP

Tank

CP-LA-01

File: Bulk Entitlement Schematics.ppt

Last modified: 09/11/2023

By: Mairead McMillan

Version: 1

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GWW Context

‘How we will deliver on customer outcomes’

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Context

Custome Affordability
GMUWSS/SWS Expectations/committments around:

Water security (GMUWSS levels of service) and price sub same levels of service

Quantity
Water quality

TO returns, Water is Life
Reducing impact on waterways and Coutnry
Benefiical use of recycled water
IWM and IWWMB
Population growth – Housing Statement.
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