Integrated Water Cycle
Management Strategy
Summary Document
Laverton Stormwater Harvesting Project
Integrated Water Cycle Management Strategy Summary Document
Contents
Executive Summary
3
1. City West Water’s Changing Service District
4
2. City West Water’s Changing Infrastructure
5
3. Vision and Principles
6
4. Key Directions
8
5. Integrated Water Cycle Management
11
5.1 Future Demand and Growth
11
5.2 Water Supply–Demand Analysis
12
5.3
Infrastructure Portfolio Options Analysis
12
5.4 Infrastructure Requirements
12
5.5 Preferred Servicing Option – Urban Growth Area
14
5.6 14
5.7 Preferred Servicing Option – CBD and Existing Areas
17
5.8 Servicing Approach – CBD and Existing Areas
17
5.9Staged Implementation Plan of Major Infrastructure
18
6. Supporting the Strategy
19
6.1 Research and Development
19
6.2
Stakeholder Engagement
19
6.3
Greening the West
19
6.4
Victorian Planning Provisions
19
6.5
Land Acquisition Strategy
20
6.6
Regulatory Reform
20
6.7
Future Infrastructure Requirements
20
6.8
Capacity Building
20
Implementing the Strategy
20
7. 2
Infrastructure Plan – Urban Growth Area
Executive Summary
City West Water services one of the fastest
growing regions in Australia. The increase in
demand for water due to this rapid growth,
coupled with increasingly variable climate,
presents challenges to City West Water’s mission
of providing affordable and safe water and
sewerage services for today and tomorrow.
One of the ways City West Water is addressing these
challenges is through developing and implementing
sustainable integrated water solutions. By effectively utilising
all water resources available within its service district City
West Water can reduce its reliance on external potable water
supply sources, and eliminate the need to import more
potable water to meet this growth in demand.
This approach will not only help City West Water to secure
water supplies and improve liveability for its customers, but
will also help to minimise costly future investments in water
supply infrastructure augmentations.
The infrastructure solutions also aim to maximise sustainable
water supplies to establish and maintain green space which
in turn can contribute to improving the health and wellbeing
of the community which supports the vision of the Greening
the West Initiative. The solutions outlined in City West Water’s
Integrated Water Cycle Management Strategy have been
developed through analysis of the interactions between
the water cycle and urban landscape, and identification of
the infrastructure required to achieve water supply, sewage
conveyance, treatment and disposal, flood mitigation,
drainage and urban amenity in an integrated manner.
This integrated planning for infrastructure to achieve multiple
water cycle management outcomes is a new approach,
hoped to deliver significant efficiencies in designing, building
and operating water management systems.
This document provides an overview of our changing service
district. It outlines the preferred integrated water cycle
management options to provide a smart and resilient water
system for a liveable, sustainable and productive Melbourne.
City West Water’s Integrated Water Cycle Management
Strategy addresses City West Water’s customer growth
through the development of a suite of infrastructure solutions
that not only provide for water supply and sewerage
infrastructure, but aim to also improve the environmental
sustainability, resilience and economic performance of the
water management system.
Afton Street Wetlands Stormwater Project
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Integrated Water Cycle Management Strategy Summary Document
1. City West Water’s
Changing Service District
population
2.3
million
1
million
175
gigalitres
water
demand
potable water
supply
alternative
water supply
active open
space irrigated
by alternative
water
103
gigalitres
per year
152
gigalitres
102
gigalitres
per year
per year
23
gigalitres
per year
1.1
gigalitres
per year
64%
39%
2015
4
per year
2025
2035
2045
2055
2065
2. City West Water’s
Changing Infrastructure
6,000
kilometres
5,250
kilometres
potable water
pipeline length
4,500
kilometres
sewer pipeline
length
4,000
kilometres
1,800
kilometres
100
alternative
water pipeline
length
kilometres
storage through
aquifer storage
and recovery
0
gigalitres
recycled water
production
facilities
2
5
stormwater
harvesting
schemes
5
35
2015
5
gigalitres
2025
2035
2045
2055
2065
5
Integrated Water Cycle Management Strategy Summary Document
3. Vision and Principles
A smart and resilient water system for a liveable, sustainable and productive Melbourne
1.
Achieve Water Security
2.Support Economic
Prosperity
3.
4.
6
Environmental Protection
Collaborative Planning
•
Improve the security of potable supplies through the provision of
alternative water supplies including recycled water, and stormwater
sources, aiming to maximise potable water substitution.
•
Water consumption per capita is limited to 240 litres per person
per day (including residential, non-residential and non-revenue
consumption) and 160 litres per person per day for residential drinking
water use.
•
Promote the efficient use of all water resources.
•
Enhance project outcomes from a triple bottom line perspective
whilst maintaining long term business viability.
•
Plan for projects that support residential and business growth.
•
Manage the impact of activities on any waterway, aquifer or wetland
to minimise environmental impacts on, and risks to, the aquatic
ecosystem.
•
Assist to maintain and restore valuable natural assets to promote
biodiversity.
•
Minimise activities that impact on the broader environment (nexus
with other sustainability agendas such as energy consumption,
resource recovery, etc.).
•
Collaborate with Government agencies, Local Government, the Water
Industry and the public and private sectors to take into account
regional needs and optimise outcomes.
•
Engage with customers and broader stakeholders to better
understand their expectations; and support the vision outlined in the
Greening the West initiative to enable sustainable, liveable and healthy
communities through urban greening. This will be achieved through
exploring and implementing IWCM initiatives.
Kooringal Golf Course, supplied with recycled water from the Altona Recycled Treatment Plant
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Integrated Water Cycle Management Strategy Summary Document
4. Key Directions
These Key Directions have been developed for the City West Water Integrated Water Cycle Management
Strategy. They provide the framework for how City West Water will work internally and engage with its
stakeholders to achieve the vision.
1.
Managing Growth
• Optimising utilisation of recycled water through
construction of a recycled water supply network
throughout growth areas
• Optimising utilisation of stormwater through localised
harvesting for irrigation of public open space and
schools.
2.
Maintaining Water within the Landscape
• Mitigate the impact of the heat island effect by
maintaining healthy trees, parks and gardens
• Support Greening the West by identifying sustainable
water supplies to maximise urban greening.
8
3.Integrated Water Cycle Management
Infrastructure
• Planning infrastructure to achieve multiple benefits
• Designed to address:
- Water Supply
- Sewerage
- Drainage
- Flood Management
- Stormwater Quality
- Amenity
• Integrating water cycle infrastructure into the urban
landscape to improve the quality and functionality of
green space.
4.
Cost Effectiveness
• Analysing an array of options in the context of
deferring the costly augmentation of centralised
potable water supply systems
• Working toward capturing the values of the
environment, health and social well-being economic
values in the assessment of options.
5.Stakeholders
• Engaging with stakeholders to ensure collaborative
planning
• Creating partnerships to ensure the effective
continued operation of infrastructure, and
achievement of desired outcomes.
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Integrated Water Cycle Management Strategy Summary Document
Green Gully Stormwater Project storage pond under construction, 2013
Green Gully Stormwater Project storage pond, 2016
10
5. Integrated Water Cycle Management
As Melbourne continues to grow there is increased
demand on water supply infrastructure and
degradation of waterway ecological systems.
This, in addition to increasing climate variability,
is placing pressure on urban water systems.
Melbourne has several water cycle management systems
operating separately to typically achieve a single outcome.
Such systems include potable water supply, sewage
conveyance, treatment and disposal, stormwater drainage
and flood mitigation. These systems have been designed
and constructed independently of each other without the
exploration of how these systems may work together.
The planning and management of such systems may be
undertaken through an integrated approach to create an
optimal, synergistic suite of water management infrastructure
and systems in order to facilitate the development of
Melbourne as a Water Sensitive City.
This Integrated Water Cycle Management Strategy builds on
City West Water’s infrastructure planning processes. To enhance
this work and in turn develop new infrastructure solutions,
additional inputs have been considered including drainage,
stormwater, environmental protection, waterway health and
the amenity value of the urban landscape.
5.1 Future Demand and Growth
Demand for water resources will significantly change over the
next few decades. The primary variables that will determine
water demand will be the rate of population growth, climate,
water efficiency and community behaviour to water use. In
addition to this, the urban habitat and environment will also
become a more important water demand moving forward in
order to maintain our cities liveability and provide urban heat
island benefits.
Current projections indicate the total water demand (for
residential and non-residential uses) across City West Water’s
service district will increase by up to 70% over the coming 50
years, not including environmental demand for water. In order
to provide for future demand (while minimising the need for
increases in supply from the centralised system), City West
Water aims to continue to diversify supply through integrated
water cycle management opportunities and investment in
cost-effective water efficiency measures.
5.1.1Waterway Health and Environmental Flows
Our rivers and creeks have natural patterns of high and low
flow consistent with the seasonal variation of rainfall and runoff.
Plants and animals rely on these flows for reproduction and
survival within the river systems. These patterns can be altered
by human intervention such as irrigation, damming of rivers,
land development which changes the imperviousness and
runoff patterns and groundwater extraction to name a few.
Climate change is also changing the amount of rainfall that
rivers receive either with lower rainfall or the more intense
storm surges. All of these factors can have detrimental effects
on our aquatic wildlife.
Maintaining water in the urban area plays an important role
in regulating the temperature and minimising the urban
heat island effect. As the built form of the urban environment
densifies to support higher density populations, green spaces
such as lawn and gardens are lost. Additionally imperviousness
increases, reducing the ability of water to infiltrate into soil and
provide base flows to waterways. These modifications to the
urban water cycle reduce waterway health and increase the
urban heat island effect.
As such, environmental flows are used to mimic the natural
flow regime of a river in order to support the rivers ecological
processes and wildlife. Environmental flow regimes is not just
about the amount of water provided but also the timing and
quality, i.e. environmental flow requirements are much higher
during winter and spring and lower in summer and autumn.
Water can be supplied by City West Water to ameliorate these
detrimental effects of urbanisation. Through building water
supply diversity and reducing dependence upon centralised
water supplies, City West Water aims to be in a position to
supply water to the environment, be it for additional irrigation,
release to waterways or even for urban cooling.
The Integrated Water Cycle Management Strategy aims to
create City West Water’s service district as an area abundant in
water resources such that water may be used in coming years
to improve the liveability of urban areas and improve the health
of the environment and the community.
There are five river systems that can receive environmental
water in the Central Region of Victoria including the Yarra and
Tarago systems in the east and the Werribee, Moorabool and
Barwon systems in the west. Melbourne Water manages the
water that is extracted from the rivers in the Yarra and Lower
Maribyrnong catchments. The other catchments in the Central
region are managed by Southern Rural Water.
5.1.2
Environmental Demand for Water
We understand that the environmental flows are likely to
be a considerable demand for water across our service area,
however, the volume and timing is not always clear. The
information available on the actual demand for environmental
flows is currently dependent on the size and understanding of
the waterway.
Moving forward we see this as an important demand that we
need to service, not only to provide water to the environment,
but also to provide the greater overall benefits of liveability and
urban cooling.
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Integrated Water Cycle Management Strategy Summary Document
As such, we will continue to work with key stakeholders
including Melbourne Water, the Environmental Water Holder
and Southern Rural Water to understand the likely demands for
environmental flows across our region.
5.1.3
Liveability and the Urban Habitat
Liveability reflects the wellbeing of a community and
represents the many characteristics that make a location a
place where people want to live now and in the future. In
terms of our integrated water cycle management strategy, we
need to understand the role of integrated water management
especially with regard to the water cycle in achieving positive
liveability outcomes.
Delivering much more than just aesthetics, green spaces
have proven benefits for the environment and for our health.
They filter and improve the air we breathe, keep cities cool
and provide shade for our houses and streets. They enhance
our satisfaction and wellbeing when we love, work or play
in them. They give us the opportunity to connect with each
other and nature.
Water Supply–Demand Analysis
The assessment of potential alternative water demand
locations across City West Water’s service district identifies there
is significant potential for use of alternative water to meet the
increasing demand across City West Water’s service district now
and into the future.
The geographic variation in alternative water demand illustrates
the fact that a ‘one size fits all’ approach is not appropriate. It
emphasizes the need to investigate all possible supply options
for any given area, including physical integration of supply
sources, to provide the optimal solution.
The water supply-demand balance involved an assessment of
future substitutable demands across City West Water’s service
area and the design of infrastructure portfolio options for each
of the water sources to supply the identified demand. An
example of the water supply–demand analysis (sewer mining
suitability criteria) is presented in Figure 1 (opposite).
5.3
Infrastructure Portfolio Options Analysis
In order to ensure we embrace the efficient use of water
throughout the next and any future droughts, we need to
recognise the urban habitat (including in the private realm) as
a demand for water and ensure we are placed to deliver this. As
such, our integrated water cycle management approach needs
to assist in delivering water to the urban habitat.
A range of infrastructure options are available to City West
Water to service its service district. These options range in
scale from localised stormwater harvesting options, through
to centralised recycled water supply from Western Treatment
Plant. Other options also include integration of water supply
projects external to City West Water’s service district.
5.1.4
The timeframe over which these projects may be implemented
vary, for some, implementation is short term otherwise the
opportunity will be lost, for others, due to the long term nature
of the planning (capturing the potential implications
of climate change), incremental implementation, and flexibility
of the option, these opportunities can be considered only
when, and if, the need arises. The costs and benefits of each of
these options are assessed and prioritised using an Evaluation
Framework to determine the preferred servicing option.
Climate Change
We observe climate change due to natural and manmade
causes. This is a challenge for City West Water in terms of
protecting our existing assets and providing a consistent and
high quality service to our customers with the likely increase in
frequency and magnitude of climatic conditions.
We have already had to adapt to extreme climatic and weather
events in Victoria as seen with the millennium drought, floods,
power outages and other disruptions. In order to be prepared
to respond to any future climate related risks in a timely manner
we need to ensure that we plan appropriately for it. One of
the biggest challenges however, is that we do not know what
we need to plan for which is why we need to consider
adaptive planning.
Adaptive planning refers to the need for us to consider varying
climate scenarios in our integrated water management
planning. The Victorian government in collaboration with
the water industry has set up a working group to agree on the
climate scenarios to be adopted for water resource planning.
It is likely that we will run with two scenarios including a
“Worst Case Scenario” and “Most Likely Scenario”. These will
be agreed across the industry to ensure a consistent approach
and will ensure that our integrated water cycle management
plans consider varying climate scenarios. This is not only
relevant to the access to water resources but also demand
for water and implications of flooding and sea level rise across
our service area.
12
5.2 The preferred servicing option for the future servicing of
City West Water’s service district incorporates a centralised
alternative water network which utilises recycled water,
stormwater and aquifer storage and recovery. Further detail
of the preferred servicing option is provided in Section 5.5.
5.4 Infrastructure Requirements
City West Water’s future water security will be delivered through
continued utilisation of the conventional potable water supply
system and a balance of investment in alternative water
services and water efficiency.
Through assuming a likely scenario for climate variation,
population growth and water efficiency, a range of
infrastructure servicing options have the potential to achieve:
•
up to 23 gigalitres per annum of alternative water supply
across City West Water’s service district by 2065
Sewer Mining Suitability
Spatial Criteria
Sewer Mining Suitability
The suitability of a location for sewer mining. This is
the combined score of all sewer mining suitability
criteria layers, weighted by City West Water
Water.
Demand Volume
Locations with greater demand are more suitable.
Distance to Source
Demand that is closer to a source is more suitable (there
are multiple combinations of distance to sewers with
different suitability ratings; therefore this criterion is
optimised to select the combination with the best score).
Supply Potential (Sewer Diameter)
Sewers with larger diameters are more suitable (sewer
diameter is used a proxy for available volume).
Sewer Depth
Sewers with shallower depth are more suitable
Wastewater Salinity
Sewers containing wastewater with lower
lower salinity are more
suitable.
Land Availability for Treatment Plant
Demand that is closer to an area of open space that may
suitable.
be suitable to locate a treatment plant, is more suitable
Site Conditions
Construction is more difficult or expensive
expensive in more
developed location.
Ground Conditions
Ground conditions encountered during construction impact
the suitability of a location (e.g. clay
clay is more suitable than
rock).
Figure 1: Water Supply–Demand Analysis Example – Sewer Mining Suitability Criteria
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Integrated Water Cycle Management Strategy Summary Document
•
deferral of the need for large scale potable water supply
investment; and
•
significant potable water substitution.
The opportunity presented across the Urban Growth Area is
attractive due to the benefits of implementing these systems
in association with new urban development. The Strategy
provides emphasis on the Urban Growth Area to ensure build
out does not precede the necessary planning and design for
integrated water servicing infrastructure.
There are also significant opportunities across the CBD and
Existing Urban Areas. The diversity of the opportunities within
these areas require more detailed investigation and City West
Water will work with its key stakeholders in order to develop
the right mix of infrastructure in order to service these areas in
the future.
5.5 Preferred Servicing Option –
Urban Growth Area
The Urban Growth Area provides a unique once only
opportunity to provide a dual supply system on a large scale.
Primarily this is due to the potentially prohibitive cost of
retrofitting a third pipe system in existing urban areas and
residential dwellings/commercial and industrial buildings rather
than the comparatively cheap cost of installing during the
construction of a the new urban developments and buildings.
5.5.1Water
The preferred water servicing option for the Urban Growth
Area is built upon large centralised potable and alternative
water supply systems which are complemented by localised
stormwater capture and reuse, as outlined in Figure 2. These
systems provide a resilient and sustainable infrastructure mix to
ensure future water security.
Drinking water will be supplied from Melbourne’s drinking
water supply network. Recycled water will be sourced from
two separate treatment plants at Western Treatment Plant and
the planned Ravenhall Alternative Water Production Facility.
Stormwater will be sourced from local catchments.
The preferred option also includes the potential to integrate
stormwater harvesting with dual reticulated recycled water and
aquifer storage and recovery. Where conditions suit, stormwater
may be treated further to an Class A equivalent standard and
injected into the recycled water network. Aquifer storage and
recovery may also be utilised to store this water for use when
needed.
5.5.4Stormwater Drainage and Flood Mitigation
City West Water has no direct responsibility for managing
stormwater, either through the retaining of water to mitigate
flooding, or through its disposal through drainage. However,
to ensure the Strategic Vision is realised City West Water will
work with the relevant authorities to ensure the design of
these systems follows the principles of Integrated Water Cycle
Management and synergies with City West Water’s infrastructure
are explored and implemented.
City West Water has developed close relationships with
municipal authorities and Melbourne Water and is collaborating
with these organisations to ensure the installation of any
stormwater drainage or flood mitigation infrastructure aligns
with this Strategy.
5.5.5
Aquifer Storage and Recovery
There is typically a higher demand for alternative water during
the summer months than at other times of the year due to
irrigation demands, and building an alternative water treatment
plant to meet the summer peak is undesirable. One means
through which this over investment can be avoided, without
the need to utilise potable water, is through storing excess
alternative water produced during low demand winter months
and utilising both production and stored water during the high
demand summer months.
The challenge associated with this concept lies in the
construction of suitably sized storages to store the alternative
water required. Under the Strategy the preferred option
involves the use of aquifer storage and recovery to achieve
the storage requirements, particularly in the Urban Growth
Area. City West Water is undertaking several investigations
into the hydrogeology of Melbourne’s west, with the initial
results promising.
5.5.2Sewerage
Sewerage services will also be provided through established
means with sewerage collected primarily through gravity
based systems and transported to Western Treatment Plant and
the proposed Ravenhall Alternative Water Production Facility.
5.5.3
Stormwater Treatment and Harvesting
The preferred option includes distributed stormwater treatment
systems throughout the many stormwater catchments across
the Urban Growth Area. Where possible these systems should
also provide flow retardation for flood management, and
storage of water for use on nearby public open space for
irrigation. The land area and capital cost of such systems may
be kept to a minimum through designing the infrastructure to
meet all three of these outcomes within a single installation.
14
5.6 Infrastructure Plan – Urban Growth Area
In order to meet future demands in the Urban Growth Area
City West Water will incrementally augment the major servicing
infrastructure. The flexibility provided in the infrastructure
rollout plan allows for timely staging of new major assets while
the use of existing assets are optimised in order to provide the
most cost effective servicing strategy.
5.6.1
West Werribee Dual Supply Area
The West Werribee Dual Supply Project (Area D) will provide
potable water and alternative water services to over 34,000
homes in the Wyndham West area.
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Integrated Water Cycle Management Strategy Summary Document
The project will comprise potable water supply from the
centralised system with a storage tank at the Ballan Rd Tank
Site. Recycled water will be supplied via the recycled water
treatment plant at the Western Treatment Plant and an
alternative water storage at the Ballan Rd tank site. The supply
sources are being optimised for alternative water through the
implementation of aquifer storage and recovery at Western
Treatment Plant with investigation underway to explore
aquifer storage and recovery at the Ballan Rd tanks site. Further
benefit to the water supply systems may be provided by the
implementation of localised stormwater harvesting schemes.
The increased storage capacity offered through the operation
of aquifer storage and recovery at Western Treatment Plant
and Ballan Rd Tank Site will allow the peak summer demands
to be met while delaying the need to augment the treatment
plant at Western Treatment Plant. The capture and reuse of
stormwater will provide an additional supply of alternative
water, either locally for active open space or on a larger scale
for re-injection into the third pipe system or aquifer storage and
recovery, again potentially delaying the augmentation of the
treatment plant at Western Treatment Plant.
5.6.2
The Greek Hill Dual Supply Project (Area B & C) will supply up to
42,000 homes with potable and alternative water in the Greek
Hill area, and provide a link between the West Werribee Dual
Supply Project (Area D) and the Holden Dual Supply Project
(Area A). The link between the projects will provide flexibility in
servicing options and allow the most cost effective timing of
infrastructure options.
It is planned the potable water supply will be sourced from
the centralised system through a distribution tank at Greek Hill.
Recycled water will be sourced from the Western Treatment
Plant and the proposed Ravenhall Alternative Water Production
Facility. There is also opportunity to optimise the supply
from Ravenhall Alternative Water Production Facility through
integration with the Ballan Rd aquifer storage and recovery
system. Again, further benefit to the water supply systems may
be provided by the implementation of localised stormwater
harvesting schemes.
Figure 2: Key Alternative Water Infrastructure Options for the Urban Growth Area
16
Greek Hill Dual Supply Area
5.6.3
Holden Dual Supply Area
The Holden Dual Supply Project (Area A) will supply up to
20,000 homes with potable and alternative water in the Holden
supply area. Potable water supply will be sourced from the
centralised system with a distribution tank at Holden. Recycled
water will be sourced from the proposed Ravenhall Alternative
Water Production Facility and there is also opportunity to
optimise the supply sources for alternative water through the
implementation of stormwater harvesting.
The capture and reuse of stormwater will provide an additional
supply of alternative water, either locally for playing fields or on
a larger scale for re-injection into the third pipe system and/or
aquifer storage and recovery.
5.7 Preferred Servicing Option –
CBD and Existing Areas
For the CBD and Existing Urban Areas a range of options
were explored for servicing through integrated water cycle
management. The areas presented in this Strategy focus on
the preferred servicing option for the future redevelopment
proposed at Arden Macaulay, E-Gate, Docklands and
Maribyrnong Defence Site. These areas are identified as being
attractive for alternative water supply due to the opportunity
for the installation of dual reticulation while these areas are
being redeveloped. There is also consideration of opportunistic
projects like the Stony Creek Stormwater Harvesting Project
which looks to address multiple water cycle benefits associated
with reductions in stormwater volumes and associated nutrient
loads to the receiving waters.
The preferred water servicing option for the CBD and Existing
Urban Areas is built upon the existing centralised potable
water system and is complemented by opportunistic regional
or localised alternative water supply systems. There is also the
opportunity to develop an alternative water supply network
to service parts of these areas i.e. linking Arden Macaulay and
E-Gate.
Sewerage services will also be provided through established
means with sewerage collected primarily through gravity
based systems and transported to Western Treatment Plant and
the Altona Treatment Plant. Opportunities for localised sewer
mining will be considered for future urban redevelopment
areas.
In order to meet future demands in the CBD and Existing Urban
Areas City West Water will incrementally augment the major
water and sewerage servicing infrastructure, while developing
opportunistic solutions for the provision of alternative water.
The flexibility provided in the infrastructure rollout plan allows
for timely staging of new major assets while the use of existing
assets are optimised in order to provide the most cost effective
servicing strategy.
5.8 Servicing Approach – CBD and
Existing Areas
5.8.1Arden Macaulay, E-Gate, Docklands Redevelopment
The redevelopment of the Arden Macaulay, E-Gate and
Docklands areas are planned to continue over the next 30 years
with up to 2 gigalitres per year of alternative water demand
identified in the area. The analysis conducted illustrates that
there are sufficient suitable local supply sources within the
redevelopment area to supply alternative water to meet the
expected demands.
Based upon the analysis undertaken, the preferred option is to
provide a supply of recycled water for non-potable demands
either from a local sewer mining plant or a regional treatment
plant. While this option does not receive the benefits of the
stormwater harvesting, the option delivers the high levels of
alternative water supply required to meet the holistic water
supply objectives. Further work must be undertaken to
determine the optimal supply arrangement for recycled water
supply and harvested stormwater to supplement the recycled
water system and in doing so achieve environmental benefits.
5.8.2
Maribyrnong Defence Site Redevelopment
The Maribyrnong Defence Site is planned to be redeveloped
over the next 30 years with up to 0.35 gigalitres per year of
alternative water demand identified at the site. The options
assessment process analysed a mix of infrastructure options,
including recycled water, stormwater, rainwater and aquifer
storage and recovery. Analysis conducted to date illustrates
that there is a significant resource of alternative water available
to service non-potable water demands.
Based upon the analysis undertaken the preferred option is
sewer mining with water sensitive urban design. This provides
a high quality and reliable recycled water supply to the
development, while the water sensitive urban design provides
the environmental benefits. Further work must be undertaken
to explore whether these elements may be integrated, and
whether any stormwater harvesting may take place.
5.8.3
Stony Creek Restoration Project
The Greening the West initiative has brought together a
partnership between Melbourne Water, City West Water,
Brimbank City Council, Places Victoria and Greenfleet to restore
a section of concrete channel in Sunshine known as Stony
Creek. The project aims to restore the creek into a natural
waterway and incorporate walking paths, trees and vegetation
as well as converting the existing retarding basin to a natural
wetland.
The project offers a unique opportunity to rehabilitate Stony
Creek and establish wetlands at the Gilmour Road site allowing
for effective integration of water and vegetation into the
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Integrated Water Cycle Management Strategy Summary Document
landscape to improve the community’s access to quality open
space for walking, socialising and improving the liveability of
the suburb. In addition, the project will manage urban water
flow and the opportunity to store and harvest stormwater for
irrigation use.
5.9Staged Implementation Plan of Major
Infrastructure
The preferred servicing options require significant investment
in water supply infrastructure throughout City West Water’s
service district. The rollout plan below (Figure 3) illustrates
the scheduling of infrastructure required to achieve
benefits associated with deferring centralised water supply
infrastructure upgrades, and environmental benefits to
waterways and the Bay.
Water Plan 3
Water Plan 4
Future Infrastructure Plans
WWDSP
WTP ASR
Greek Hill Dual Supply Project
Ballan Rd ASR
ARWP II
Holden Dual Supply Project
Ravenhall TP
Ravenhall ASR
Tarniet WM
Holden OS
WNOS
Greek Hill ASR
Ravenhall Stage II
WWDSP II
Continued investment in decentralised stormwater harvesting projects and decentralised recycled water projects
2015
2020
Key:
Figure 3: Infrastructure Rollout Plan
18
2025
Water Projects
2030
Sewer Projects
... 2060
Alternative Water Projects
Altona Recycled Water Treatment Plant infrastructure
6. Supporting the Strategy
6.1 Research and Development
City West Water’s Integrated Water Management Strategy
outlines a servicing strategy for City West Water for the next 50
years. Over this time technology will continue to improve and
the integration of new technology into the Strategy can have
significant benefit. Improvement and development of existing
and new technology is encouraged to provide ongoing
support to City West Water’s Integrated Water Management
Strategy.
6.2
Stakeholder Engagement
Stakeholder engagement undertaken as part of the
development of the Strategy indicated stakeholder
perceptions in regards to the drivers for mainstreaming
integrated water cycle management are closely aligned with
City West Water’s drivers.
City West Water cannot achieve the opportunities without
significant involvement from key partners, including the
community, Department of Environment, Land, Water and
Planning, Metropolitan Planning Authority, Essential Services
Commission, Environment Protection Agency (Victoria),
Local Government, Melbourne Water and industry. City West
Water’s Integrated Water Management Strategy commits to
building relationships through a consistent and transparent
engagement process.
6.3
Greening the West is a regional initiative that is enriching
communities in Melbourne’s west through the development of
green spaces. The initiative is aiming to deliver positive health
and social outcomes and enhance liveability for communities in
the western suburbs of Melbourne. It seeks to do this by taking
a regional approach to urban greening to reduce the impact
of the heat island effect; fostering projects and activities that
deliver increased vegetation and access to, and use of quality
green space. City West Water’s Integrated Water Management
Strategy aims to provide water resources to enable Greening
the West projects and initiatives to achieve their outcomes.
Greening the West
6.4
Victorian Planning Provisions
The planning requirements for residential subdivision are
set out in Clause 56 of all planning schemes. Clause 56.07 –
integrated water management, provides a basis for managing
water in residential subdivisions by conserving potable
(drinking) water, providing opportunities for reusing and
recycling water for non-drinking purposes and managing the
quality as well as quantity of urban run-off.
Further investigations by City West Water will be undertaken to
determine an effective way to utilise these Planning Provisions
to facilitate the delivery of the Strategy. For example City West
Water currently utilise the Planning Permit process for new
subdivisions to require developers to provide alternative water
supply assets, however in the future the use of overlays, or
similar planning tools, may be employed.
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Integrated Water Cycle Management Strategy Summary Document
6.5
Land Acquisition Strategy
City West Water is currently preparing a Land Acquisition
Strategy which outlines future land purchase requirements
in order to service the future urban growth across City West
Water’s service district. The Land Acquisition Strategy provides
the basis for future land acquisition requirements, not only
within the Urban Growth Area but also within the CBD and
Existing Urban Areas.
6.6
Regulatory Reform
The institutional and regulatory environment in which
the water industry operates provides both challenges
and opportunities to the implementation of integrated
water cycle management. Continued effort is being made
with stakeholders and regulators to reduce barriers to the
implementation of integrated water cycle management where
the benefits are justified.
6.7
Future Infrastructure Requirements
The asset renewal plan will be utilised in order to coordinate
future alternative water asset opportunities and construction.
The coordination of works will allow for more efficient delivery
of alternative water assets, when constructed in combination
with potable water assets, and potentially lead to cost savings.
Smart networks have the potential to assist in the operation
and planning of integrated water cycle management
opportunities now and into the future. Also, opportunities to
reduce the main sizes of the potable water distribution system
will be identified during the detailed planning of the potable
and alternative water systems.
6.8
Capacity Building
Integrated water cycle management entails a new set of
infrastructure being integrated into the water supply system.
The safe and efficient operation of this infrastructure requires
skilled and able professionals. Currently the water industry
is not yet fully equipped to manage the roll-out of City West
Water’s Integrated Water Management Strategy and investment
will need to take place over the coming years to develop the
expertise required to enable the successful transition to the
infrastructure portfolio outlined in City West Water’s Integrated
Water Management Strategy.
7. Implementing the Strategy
City West Water’s Integrated Water Management
Strategy outlines City West Water’s potential to
implement integrated water cycle management
infrastructure to enable a healthy, liveable and
prosperous Melbourne.
To achieve this City West Water must continue its
implementation of planned projects, prove the value of future
infrastructure portfolio options and create an environment in
which this infrastructure may be efficiently operated. This may
be achieved through building capacity within the industry,
resolving regulatory barriers and better quantifying the benefits
of these initiatives.
The implementation of the Strategy will require City West Water
to further strengthen collaboration throughout the planning
process across both internal and external stakeholders and
utilise the momentum established by initiatives such as
Greening the West. This approach will ensure that the right mix
20
of water infrastructure and services are being delivered.
While the Strategy proposes servicing solutions, the solutions
are flexible. As more information becomes available, the
Strategy will be updated and refined to incorporate this new
understanding. In doing so, the Strategy remains dynamic and
adaptable aiming to provide the best integrated water cycle
management solutions that will enable a the realisation of City
West Water’s vision for Melbourne.
21
City West Water 2016
1 McNab Avenue
Footscray Vic 3011
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ISSN: 2203-9910 (Print)
ISSN: 2203-9929 (Online)