Annual Water Outlook Western Water December 2020 - Western Water main draft version
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Annual Water Outlook Western Water December 2020
ANNUAL WATER OUTLOOK 2020/21
Summary
Western Water’s vision is Strong Communities, Growing Together. Ensuring secure water supplies
for our customers is central to achieving this.
Western Water’s Annual Water Outlook focusses on the next 12 months, while taking a longer-term
view of water supply to customers over the next five years. This document is produced annually to
provide water supply availability information to customers and stakeholders. This Annual Water
Outlook reviews the 2019/2020 financial year and looks forward from 1 November 2020 to 30
November 2025. No water restrictions are forecast for 2020/2021.
The table below is a summary of the Outlook for all regions in the Western Water service area.
Table 1: Summary of the Annual Water Outlook for Western Water’s service region
Likelihood of water Summary of the system operation
Supply
Towns supplied Sources of supply restrictions in the and supply measure over the next 12
system
next 12 months months
Kerrie, Forsters, Wrights, Supply from surface water reservoirs
Garden Hut Reservoirs supplemented with supply from local
Romsey- Lancefield groundwater sources. If required
Groundwater Very unlikely
Lancefield Romsey water may be supplied from the
Rosslynne Reservoir
wider water grid, including the
Melbourne system Melbourne system.
All supply from Pykes Creek
Myrniong Myrniong Pykes Creek Reservoir Very unlikely
Reservoir.
Sunbury Gisborne, Macedon, Mt Macedon and
Riddells Creek supplied from
Diggers Rest Rosslynne Reservoir. Transfers from
Rosslynne Reservoir the Melbourne system to Rosslynne
Bulla
Macedon & Mt Macedon Reservoir are anticipated over the
Rosslynne Gisborne Very unlikely outlook period to ensure water
storages
Macedon security to these towns.
Melbourne system
Mt Macedon Sunbury and surrounding small
towns are supplied directly from the
Riddells Creek Melbourne system.
Melton
Bacchus Marsh Melton and surrounding small towns
Merrimu Reservoir supplied from the Melbourne system.
Eynesbury
Merrimu Djerriwarrh Reservoir Very unlikely Bacchus Marsh supplied from
Rockbank
Melbourne system Merrimu Reservoir supplemented by
Toolern Vale Djerriwarrh Reservoir.
Long Forest
Campaspe Reservoir, Supply from local surface water
Reservoir C, Graham Brock reservoirs, supplemented with supply
Reservoir and Mt Macedon from Mt Macedon storages.
Woodend Woodend storages Very unlikely Transfers from Rosslynne or the
Melbourne System are forecast in the
Rosslynne Reservoir
next 12 months under most
Melbourne system conditions.
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Authorised: GM Planning and Capital Delivery Date Authorised: 1 December 2020
ANNUAL WATER OUTLOOK 2020/21
1. Introduction
The region serviced by Western Water forms part of north-western metropolitan Melbourne and is
bounded by Lancefield in the north, Eynesbury in the south, Bulla to the east and Myrniong to the
west. Major towns serviced by Western Water include Melton, Sunbury and Bacchus Marsh.
Population in the region was estimated at 183,715 in June 2020, an increase of 6.1% from 160,339
in June 2019.
Water supply for the region is provided through a local water grid, supplied by a mix of surface
water from local water storages, groundwater, the Melbourne system and recycled water. Water
security for the region is reliant on an interconnected transfer network, which allows water from the
wider area to be transferred to where it is most needed.
Western Water’s water resources are defined through Bulk Entitlements, Take and Use Licences
(groundwater), and water shares. The Western Water region presents some exceptional challenges
and opportunities for water resourcing due to the fast rate of growth and urbanisation in the region,
the impact of farm dams and climate change on local catchment yields.
1.1 2019/20 snapshot
1.1.1 Key achievements
In 2019/20, Western Water enhanced its water supply security through the following:
• Progressed the implementation of the Urban Water Strategy and commenced program of
work for its update in 2022
• Completed the feasibility study for expanding water grid connections to and within the
Western Water region. Outcomes have been incorporated into Western Water’s capital
program and further investigations have commenced
• Purchase of the unallocated water in Merrimu Reservoir for an additional 10% of inflow
volume and 20% of storage share of the reservoir
• In partnership with stakeholders, commenced the Western Growth Area integrated water
management master plan
• Actively supported government led initiatives including the Central Region Sustainable Water
Strategy, Long Term Water Resource Assessment and Integrated Water Management Forums
• Progressed business case for improved utilisation of local surface and groundwater
management in Romsey and Lancefield following completion of water treatment master plans
• Continued the design for the upgrade of key transfer assets through Sunbury. Upgrades to
water pump stations are likely to commence late 2020.
• Began scoping technical requirements of recommendations from the Sunbury community
deliberative panel undertaken as part of the Sunbury’s Water Future initiative – a partnership
project with Melbourne Water.
• Produced 9,151 million litres (ML) of recycled water and saved about 4,428 ML of drinking
water through beneficial reuse.
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ANNUAL WATER OUTLOOK 2020/21
1.1.2 Rainfall and streamflow
Rainfall in 2019/20 was above the long-term average for most of the region. This rainfall correlated
to most systems receiving above-average streamflow. Timing of rainfall was divided between low
rainfall between July and December, above average Summer rainfall followed by high Autumn
rainfall and average rainfall in May and June. July and August saw good yields in all of Western
Water’s catchments, but increased rainfall in January to April 2020 did not result in significant
inflows to Merrimu. Rosslynne was the best performer in 2020 up to June, as it received good
inflows starting in April. With water trading and transfer from the Melbourne system to Rosslynne,
the aggregate volume of storages that supply water to Western Water are currently holding 465 ML
more than on release of the previous annual water outlook on 1 December 2019. Annual rainfall and
inflows to key reservoirs are depicted in Figure 1 and Figure 3 below. Figure 2 shows the monthly
rainfall patterns in Western Water’s catchments. It is important to note the relationship between
rainfall and catchment inflows is complex due to infiltration in the upper catchment causing a delay
to peak inflows.
Regional rainfall
1000
800
600
mm
400
200
0
Merrimu Rosslynne Lancefield Woodend
2018/19 2019/20 Annual Mean
Figure 1: Annual rainfall in the Western Water region. The average rainfall is over all records which
varies between sites.
Regional Rainfall Against Monthly Mean
Monthly Rainfall (mm) - Mean (mm)
150
100
50
0
-50
-100
Jul-19 Aug-19 Sep-19 Oct-19 Nov-19 Dec-19 Jan-20 Feb-20 Mar-20 Apr-20 May-20 Jun-20
Merrimu Rosslynne Lancefield Woodend
Figure 2: Rainfall in Western Water Catchments. Regional monthly rainfall mapped against the
regional mean for all years on record shows average to below average rainfall from July to
December, followed by above average rainfall from January to April. Reduced demand can be at
least partially attributable to this rainfall in key irrigation months.
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Authorised: GM Planning and Capital Delivery Date Authorised: 1 December 2020ANNUAL WATER OUTLOOK 2020/21
Inflow to major systems
16,000
14,000
12,000
10,000
Kilolitres
8,000
6,000
4,000
2,000
0
WW Melbourne allocation Merrimu Reservoir Rosslynne Reservoir
2018/19 2019/20 1997-2017 50th % year
Figure 3: Inflows to major storages. Inflows presented for the Melbourne system are Western
Water’s allocation only. Inflows presented from Merrimu and Rosslynne are all flows into the
reservoirs. Western Water has a 80% and 86% share of these inflows respectively. Inflows to
Rosslynne includes a volume of 1,948 ML transferred from Western Water’s Melbourne system water
account.
Inflow to small local systems
2,000
1,500
Kilolitres
1,000
500
0
Kerrie Reservoir Campaspe Reservoir Orde Hill Reservoir Garden Hut Reservoir
2017/18 2019/20 1997-2017 50th % year
Figure 4: Inflows into key small local systems. Kerrie Reservoir supplies Romsey, Campaspe and
Orde Hill Reservoir supply Woodend while Garden Hut Reservoir supplies Lancefield.
1.1.3 Water consumption
Water consumption in Western Water's service region decreased by 2.1% to 16,143 million litres
during 2019/20 compared to 16,477 million litres the previous financial year. A portion of the
decreased water consumption is likely due to the higher than average rainfall in late Summer and
early Autumn.
The per capita daily residential consumption took a healthy step down from 195 in 2018/19 to 179
in 2019/20. This low use is likely related to the prolonged periods of ample rainfall during the
Summer and Autumn seasons.
The residential consumption per person is higher than metropolitan Melbourne.However, a study
completed in 2018/19 demonstrated Western Water’s customers are using a similar amount of water
per property size. Western Water’s customer base has a higher proportion of large block sizes, which
are more reactive to rainfall patterns, than metropolitan Melbourne.
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Western Water is committed to the Target 155 program aimed at reducing customer water usage.
Advice on helpful ways to save water can be found at https://www.westernwater.com.au/Help-
Advice/Save-water
80,000
Water Connections
70,000
60,000
50,000
40,000
Figure 5: Serviced residential water connections in the Western Water region
Annual connections, consumption & demand trends
17,000 400 LEGEND
16,000
Litres / person / day
350 No restrictions
Consumption (ML)
15,000 PWSR's
14,000 300 Stage 1
13,000 250 Stage 2
Stage 3
12,000 200 Stage 3a
11,000 Stage 3a + T155
10,000 150 Stage 4
9,000 100
95/96
04/05
96/97
97/98
98/99
99/00
00/01
01/02
02/03
03/04
05/06
06/07
07/08
08/09
09/10
10/11
11/12
12/13
13/14
14/15
15/16
16/17
17/18
18/19
19/20
Figure 6: Annual consumption and residential consumption per capita. The region wide consumption
is the height of the column, restriction stages are represented by the different colour of columns and
the litre/person/day are the white round markers.
Water consumption and supply sources
18000
16000
14000
Million litres (ML)
12000
10000
8000
6000
4000
2000
0
2014/15 2015/16 2016/17 2017/18 2018/19 2019/20
Melbourne Merrimu Rosslynne Groundwater Local reservoirs
Figure 7: Annual water consumption over the past six years and the makeup of supply sources.
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Authorised: GM Planning and Capital Delivery Date Authorised: 1 December 2020ANNUAL WATER OUTLOOK 2020/21 Of the 16,143 ML of water supplied in 2019/20, 75.9% was used by residential customers, 15.0% by non-residential customers and 9.1% was non-revenue water and network losses. Residential users make up 95.3% of Western Water’s connected water customers. Investigations have continued to identify causes of non-revenue water. The overall volume of non-revenue water is likely to be associated with the significant amount of land development and construction in the region over the previous year. Western Water has worked to identify gauging errors and potential sites for network metering. This work, combined with above average rainfall impacting demand, has resulted in a decrease of non-revenue water in comparison to years passed. Victoria's response to the coronavirus (COVID-19) pandemic has resulted in changed living and working conditions for many households in our region. As much of our community would otherwise be working outside the Western Water region, the working from home environment has resulted in higher demands. This been counteracted by above average rainfall in the summer and autumn which has reduced overall household water demand due to the decrease in outdoor use. 1.1.4 Risks The Western Water region is reliant on transfer systems to support water supply security during extended dry conditions. Western Water has increased the reliability of the transfer system in recent years by investing in back up power supplies and stand-by pumps at key sites. As demand is expected to grow, key transfer infrastructure projects are forecast in the coming years. Any delays to these key projects will present a risk to the region’s water security. Western Water relies on spare capacity in the Melbourne system to schedule transfers, and could be adversely impacted if this spare capacity were reduced. In anticipation of such events, a reserve volume of water is maintained in reservoirs so there is always a volume of water that can be locally treated and supplied if short term outages in the transfer network occur. Algae or water quality issues present a continued risk for Western Water supply sources. Poor water quality in resources can require supplementary supply from other sources. Western Water is investing in monitoring and analysis programs to assist early detection of water quality issues. Early detection is key to driving appropriate response actions, especially during peak demand periods. 2. Current water supply systems Drinking water supply for the region is a mix of surface water from local water storages, groundwater and water from the Melbourne system. Security is provided through interconnecting these supplies and having the ability to transfer water from secure supplies to areas of shortfall. Western Water’s water supply network can be described as interconnected water supply systems, supported by a drinking water connection to the Melbourne system. Recycled water is also available for supply to fit for purpose usage, reducing the demands on drinking water. 2.1 Merrimu system The Merrimu system supplies Melton, Rockbank, Bacchus Marsh, Longforest, Toolern Vale and Eynesbury. Local water is sourced from Merrimu and Djerriwarrh Reservoirs, north of Melton. There is also a connection to the Melbourne water supply system. Merrimu Reservoir is managed by Version: Final Controlled Document Document Owner: Water Resources Advisor Ref: DOC-AWO 19/20 Page 7 of 16 Uncontrolled when Printed Authorised: GM Planning and Capital Delivery Date Authorised: 1 December 2020
ANNUAL WATER OUTLOOK 2020/21 Southern Rural Water. Western Water has a Bulk Entitlement to 60% of the capacity and 70% of inflows into Merrimu. Western Water is currently finalising the potential purchase of a portion of unallocated water from the Merrimu Reservoir, which will increase security and help protect water quality impacts associated with excessive drawdown. Water from Merrimu and Djerriwarrh Reservoir is treated at the Merrimu Water Filtration Plant. Water sourced from Melbourne is supplied via a pipeline with a capacity of 45 ML/day. In addition, Class B and C recycled water is used for irrigation purposes in some areas of the system. Class A supply is available for residential and commercial use in Eynesbury and Toolern. Table 2: Summary of towns supplied by the Merrimu system, as at 30 June 2020. Town(s) Connections Population Major customers Melton 25,177 64,569 5 Rockbank 1,997 6,969 - Eynesbury 947 2,494 - Toolern 2,285 7,065 - Bacchus Marsh 9,714 24,217 3 2.2 Myrniong system Myrniong is supplied from Pykes Creek Reservoir and is Western Water’s only isolated system – it is not connected to any other system. Water from Pykes Creek Reservoir is pumped to the Myrniong Water Filtration Plant before being supplied to customers. Pykes Creek Reservoir is managed by Southern Rural Water. Western Water has a 58 ML annual bulk entitlement to the reservoir and 15ML of water shares to supply Myrniong. Table 3: Summary of towns supplied by the Myrniong system, as at 30 June 2020. Town(s) Connections Population Major customers Myrniong 112 270 - 2.3 Romsey-Lancefield system The Romsey and Lancefield water supplies are now considered one supply system after a pipeline was built to connect the two towns in 2013. There are separate potable water treatment plants for each town, the Romsey Water Filtration Plant and the Lancefield Water Filtration Plant. The majority of water for Romsey comes from Kerrie Reservoir, with contributions from groundwater, the Riddells Creek reservoirs and water transferred from the Rosslynne system. Lancefield is primarily supplied from Garden Hut Reservoir with supplementary supply from groundwater and all water sources that are available to Romsey. In addition, Class C recycled water is available for agricultural and municipal irrigation in some parts of the system. Version: Final Controlled Document Document Owner: Water Resources Advisor Ref: DOC-AWO 19/20 Page 8 of 16 Uncontrolled when Printed Authorised: GM Planning and Capital Delivery Date Authorised: 1 December 2020
ANNUAL WATER OUTLOOK 2020/21 Table 4: Summary of towns supplied by the Romsey-Lancefield system, as at 30 June 2020. Town(s) Connections Population Major customers Romsey – Lancefield 2,991 7,489 - 2.4 Rosslynne system The Rosslynne system supplies Sunbury, Diggers Rest, Bulla, Gisborne, Mount Macedon, Macedon and Riddells Creek. Water is sourced from Rosslynne Reservoir, located north-west of Gisborne, and from a connection to the Melbourne supply system. Rosslynne Reservoir is managed by Southern Rural Water. Western Water has a Bulk Entitlement to 86% of capacity and inflows to Rosslynne. Water from Rosslynne Reservoir is treated at the Rosslynne Water Filtration Plant. Water sourced from Melbourne is supplied via a pipeline with a capacity of 35 ML/day. This pipeline is connected to the Western Water transfer network via Sunbury. A series of pump stations is used to pump the water to Sunbury and to the connected systems. In addition, Class B and C recycled water is available for agricultural, commercial and municipal irrigation in some parts of the supply system. Table 5: Summary of towns supplied by the Rosslynne system as at 30 June 2020. Town(s) Connections Population Major customers Sunbury (incl. Bulla) 16,234 40,854 2 Diggers Rest 2,289 5,959 - Gisborne 4,579 11,195 - Macedon & Mt Macedon 1,245 3,151 - Riddells Creek 1,479 3,754 - 2.5 Woodend system The Woodend water supply system supplies Woodend. Water is sourced from the Campaspe Reservoir, west of Woodend, and water storages located on Mount Macedon. Water from the Melbourne system and Rosslynne Reservoir can also be supplied to Woodend. Water supplied to Woodend from Campaspe Reservoir is treated at the Marriages Water Filtration Plant. Water supplied from the Mount Macedon storages is treated at the Reservoir C Water Filtration Plant. In addition, Class C recycled water is available for agricultural and municipal irrigation in some parts of the system. Table 6: Summary of towns supplied by the Woodend system as at 30 June 2020. Town(s) Connections Population Major customers Woodend 2,343 5,730 - Version: Final Controlled Document Document Owner: Water Resources Advisor Ref: DOC-AWO 19/20 Page 9 of 16 Uncontrolled when Printed Authorised: GM Planning and Capital Delivery Date Authorised: 1 December 2020
ANNUAL WATER OUTLOOK 2020/21
2.6 Storages and Entitlements
Major storages Small local systems
1,000
40,000
800
30,000 600
ML
ML
20,000 400
10,000 200
0 0
Rosslynne Romsey -
Merrimu Lancefield Woodend
Reservoir Melbourne Pykes
Reservoir Creek
system
Current volume Empty storage Current volume Empty storage
Figure 8: Storage volumes as at 1 November 2020. Note – major storage volumes are Western
Water entitlements only.
Usage against annual cap
20,000
18,000
16,000
14,000
12,000
10,000
8,000
6,000
4,000
2,000
0
Myrniong BE
Werribee BE
Werribee BE
Macedon BE
Barringo BE
Maribynong BE
Romsey BE
Lancefield BE
Melbourne BE
Riddells Creek BE
Romsey bore licence
Lancefield bore licence
Woodend BE
Rosslynne Merrimu Djerriwarrh Greater Kerrie Garden Hut Wright Bore 3 Glenfern Rd Camapspe Mt Pierce Pkyes Creek
Reservoir Reservoir Reservoir Yarra - Reservoir Reservoir Bore Reservoir Macedon Reservoir
Thomson Storage
Annual Cap Usage
Figure 9: Comparison of entitlement usage in 2019/20 against annual cap
2.7 Forecast demands
The demand for water is a key component in water resource planning. Western Water forecasts
water demands for each town and supply system. Figure 9 below shows the region-wide bulk water
demand forecasts for 2020/21 and how demand is tracking against the forecast scenario. So far in
2020, water demand is slightly higher than forecast.
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Water demand forecasts
16,000
14,000
12,000
10,000
8,000
6,000
4,000
2,000
0
Jan
Sep
Aug
Nov
Feb
Mar
Apr
May
Jul
Dec
Jun
Oct
2020/21 Actual to date 2020/21 Forecast Bulk demand 2019/20 2018/19
Plus - Minus 10%
Figure 10: Forecast bulk water demands, possible range and previous two years of actual demand.
Western Water assesses the accuracy of it’s yearly forecast each year. In 2019/20, the yearly
forecast demand for an average year was within 250 ML of the final consumption value.
Table 7: Forecast bulk water demand by system for 2020/21.
Romsey-
Myrniong Rosslynne Woodend
Merrimu System Lancefield Region
system System System
System
9,725 ML 46 ML 715 ML 5,890 ML 559 ML 16,935 ML
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3. Climate outlook
Short term climate outlook
December to February is likely to see above average rainfall across nearly all of Australia, except
west coast Tasmania. On average, December to February temperatures are likely to be warmer than
the long-term average across parts of south-east, far west and northern coastline.
A La Niña is underway in the tropical Pacific. This typically increases the likelihood of above average
rainfall across much of Australia during spring and early summer.
Novermber to January streamflow forecasts for the Lerderderg River (primary source of inflow for
Merrimu Reservoir) indicate the chances of near-median stream flows are likely at 51%, while
chances of high or low flow are less likely, at 25% and 24% respectively. Melbourne’s four major
storage reservoirs are likely to experience below-average to low inflows for the three-month
summer period of November 2020 to January 2021.
Climate and streamflow forecasts are available from the Bureau of Meteorology.
http://www.bom.gov.au/climate/ahead/
Western Water region
Figure 11: Bureau of Meteorology rainfall outlook, December 2020 – February 2021 (issued 22
October 2020).
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Authorised: GM Planning and Capital Delivery Date Authorised: 1 December 2020ANNUAL WATER OUTLOOK 2020/21 Longer term climate trend Victoria’s climate has shown a warming and drying trend over recent decades, and this trend is expected to continue. In comparison to historical conditions, we are already experiencing higher temperatures, reductions in rainfall in autumn and winter with increases in rainfall during the warmer months in some locations. In many catchments, we have also experienced a shift in the streamflow response to rainfall, with less streamflow generated for the same amount of rain. Although there will still be a lot of variability in Victoria’s climate, the chances of experiencing warmer conditions and less streamflow is now higher than in past decades. Victoria’s Climate Science Report (DELWP, 2019) outlines observed temperature is tracking towards the upper limit of projections, and observed winter rainfall – a greater indicator of catchment inflows than annual rainfall – is tracking toward the bottom of projections. For this reason, inflow statistics that are based on past observation may not be representative of the future likelihood of resource availability. This is something to keep in mind, particularly for future Annual Water Outlooks. Because of the relatively secure nature of the resource as projected for the 2020/2021 year, this issue may not be at the forefront of mind at the current time. In the future, it may be prudent to consider scenarios that are worst on record (e.g. 99th percentile), or worse than worst on record, particularly in a period of drought when it is conceivable that inflows could be less than has been observed historically. Version: Final Controlled Document Document Owner: Water Resources Advisor Ref: DOC-AWO 19/20 Page 13 of 16 Uncontrolled when Printed Authorised: GM Planning and Capital Delivery Date Authorised: 1 December 2020
ANNUAL WATER OUTLOOK 2020/21 4. Water resources over the coming year The major storages in the region and the transfer network are the key to water security in the Western Water region. As such, the 2020/21 Annual Water Outlook is focussed on how these major systems may perform over the outlook period. Western Water is currently holding a total of 54 GL in Merrimu, Rosslynne and in the Melbourne system. Figure 12: Total system storage outlook July 2020 – July 2025. Total system storage (TSS) is the sum of Western Water's Yarra-Thomson, Merrimu and Rosslynne allocations. The percentile scenarios of projected TSS above are based on rolling model runs using the climate period of 1997- 2017 and two demand scenarios. Storage projections over the next five years show the region entering restrictions under a 5th percentile scenario model run – see Figure 12. This means, of the 20 model runs completed, the driest of the scenarios is showing the chance of triggering restrictions by March 2024. The results of the model are contingent on the planned upgrades being completed according to Western Water’s capital program. Western Water manages all water supply systems to maintain a balance between local water supply, storage buffers, consistency in water quality aesthetics and balancing transfers. With the current water volumes stored in major systems, expected demand for water and adherence to operating rules, the likelihood of entering restrictions in the Western Water region over the next twelve months is very unlikely. However, restrictions may be applied due to specific events such as infrastructure failure, extreme demand or a water quality event. No water restrictions are forecast for 2020/21. Version: Final Controlled Document Document Owner: Water Resources Advisor Ref: DOC-AWO 19/20 Page 14 of 16 Uncontrolled when Printed Authorised: GM Planning and Capital Delivery Date Authorised: 1 December 2020
ANNUAL WATER OUTLOOK 2020/21
5. Short term action plan
While no restrictions are forecast within the next 12 months, it is recognised that Western Water
faces significant future challenges in supplying water to our rapidly growing region. Western Water’s
Urban Water Strategy identifies multiple actions that are needed to ensure water security to
customers. Key actions are listed below, consisting of strategic actions (short, medium and long
term) and investment in infrastructure.
Table 8: Summary of key actions to address water supply security
Action Description Theme Timing Status
Participate in the
Collaborate and contribute to the review of the
government led
Central Region Sustainable Water Strategy, Long Engagement has
policy projects Safe and
Term Water Resource Assessment and Water Market Short commenced and will
related to water resilient
reforms that will be led by DELWP. Seek the term continue during the life of
resources detailed water supply
renegotiation of entitlements to match demand where these projects
in Water for
growth is occurring around Melbourne
Victoria
Active trading occurred
Continue to explore water trading to increase
Expand water Safe and during the year –
available water supplies. This includes temporary
resource portfolio resilient Ongoing purchase of the Merrimu
trades and permanent trades that may be presented
via water trading water supply Reservoir unallocated
opportunistically or via planned augmentations.
entitlement.
Program of works has
been developed. Design
Progress the program of capital investments to
has commenced on high
upgrade the water transfer network. The transfer Safe and Short-
Water transfer priority sites supplying
network enables Western Water to supply water from resilient medium
network upgrade water from Melbourne to
different sources around Western Water service water supply term
the Macedon Ranges with
region.
some construction likely
to commence in 2020/21.
New extraction bore
Progress the recent groundwater investigations
tested at Romsey and
completed in Romsey and Lancefield to determine the
Safe and Short- licence amended.
Local water supply benefit to water supply and incorporate in supply
resilient medium Concept design of
augmentations strategy.
water supply term Campaspe Reservoir
Commence the Campaspe Reservoir upgrade for
completed, progressing to
increasing supply security to Woodend.
detailed design.
Implement water efficiency program to move towards
Develop and
a Target of 155 litres or less of potable water per Water use Short
implement water Program has commenced.
person per day to achieve the demand forecasts efficiency term
efficiency strategy
outlined in this Strategy.
Progression of key
Continue the Sunbury and Melton Integrated Water Safe and
projects in growth areas
Collaborate with Management investigations in collaboration with key resilient
including Western Growth
stakeholders to stakeholders and actively participate in the Integrated water supply Short
area IWM Master Plan,
enact Integrated Water Management Forums. Identifying where Optimise term
Toolern Stormwater
Water Management stormwater, rainwater and or recycled water sources alternate
Harvesting and Sunbury
are suitable for replacing potable demands. water use
IWM.
Engagement activities will
Continue to engage Continue stakeholder and community engagement
increase over the next
with our during the detailed planning and implementation
two years to inform key
customers, phases of the Urban Water Strategy, Integrated Engagement Ongoing
aspects of the Urban
community and Water Management Planning and Pricing Submission.
Water Strategy and Price
stakeholders This includes engaging with Traditional Owners.
Submission.
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First projects under the
Deliver climate Western Water will lead climate change adaptation Greenhouse Gas Strategy
change adaptation across our water system by delivering initiatives to Safe and have commenced. A large
Long
initiatives to reduce work towards a long-term reduction of greenhouse resilient solar array was
term
greenhouse gas emissions and zero net greenhouse gas water supply constructed at the Melton
emissions emissions. recycled water plant in
2019.
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