2017 Metropolitan Water Plan

Water for a liveable, growing and resilient Greater Sydney

A secure and sustainable supply of water is essential for Sydney, the Illawarra and the Blue Mountains to grow and prosper. Reliable and affordable water is vital for our households, businesses and industries to thrive and remain economically competitive, nationally and internationally. Water also supports our environment and the healthy, vibrant quality of life for which Greater Sydney is famous.

The 2017 Metropolitan Water Plan is the NSW Government’s plan to ensure there is sufficient water to meet the needs of the people and environment of the Greater Sydney region, now and for the future.

Our overarching goal is to secure water for a liveable, growing and resilient Greater Sydney. To achieve this, our plan establishes key strategies to be implemented over the life of the plan and to set us on a pathway towards a water system that will meet Greater Sydney’s needs for the next 50 years.

Our plan is structured around four key outcomes:

  • a water supply that is secure and affordable
  • a water supply system that is resilient to stresses and shocks
  • more liveable and resilient urban communities
  • rivers downstream from dams that are healthy.

Securing water for the Greater Sydney region

Water is a limited natural resource, and managing it for the benefit of our community presents many challenges.

The region’s population is growing rapidly and expectations for more liveable cities are creating new and increased demands for water. Water is needed to keep our parks green and improve neighbourhood amenity, while increasing urbanisation is putting pressure on our waterways with more stormwater run-off from urban areas. In addition, a variable and changing climate means that we cannot know with certainty how much rainfall will support our water supply system in the future. All of this means we need to be able to respond in a flexible way to future demands through an adaptive approach to managing our water supplies as well as making the best use of our available water resources.

The Metropolitan Water Directorate (Metro Water), within the NSW Department of Primary Industries – Water, led and coordinated the development of the Metropolitan Water Plan for Greater Sydney. Metro Water convened teams of technical experts and decision makers who developed the strategies of the plan. The Metropolitan Water Chief Executive Officers’ Committee, comprising representatives of government agencies and major public water utilities, met regularly to provide guidance throughout the planning process. The review was overseen by the Independent Water Advisory Panel.

Engagement with a broad cross-section of the Greater Sydney community as well as stakeholders from local government, private water utilities, peak industry groups and non-government organisations helped inform the 2017 Metropolitan Water Plan.

Highlights of the plan include:

  • Optimising the way we manage the water supply system. We have made changes to the mix of water supply and demand measures (such as dams, desalination, water restrictions) so our system can provide the water security we need at the least cost.
  • Investing in water conservation. An innovative approach to determining the optimal level of investment, led by Sydney Water, means value-for-money initiatives will help save water.
  • Preparing for drought. The plan includes a Drought Response Strategy that is flexible and can respond to droughts more extreme than any in the historical record.
  • Delivering WaterSmart Cities. A new program to facilitate a more integrated approach to providing water, wastewater and stormwater services will contribute to making our communities more liveable and resilient.
  • Improving river health. Variable environmental flows will be released from Warragamba Dam to help protect and improve the health of the Hawkesbury-Nepean River.

Greater Sydney’s water supply system

Most of the region’s water is supplied from dams that capture and store rainwater from the catchment areas located above the storages.

Greater Sydney’s water supply catchment area covers 16,000 square kilometres to the west and south of Sydney, extending from Lithgow to Goulburn. It encompasses two major river systems, the Hawkesbury-Nepean and the Shoalhaven, as well as the Woronora River and 11 major dams. 

The interconnected network of dams allows water to be transferred within the system to meet the region’s demand for water. When needed, supplies can be supplemented by water from the Sydney Desalination Plant, which is a non-rainfall dependent water source. In addition, the use of recycled water and stormwater helps preserve our drinking water supplies.

Sydney Desalination Plant

The Sydney Desalination Plant helps guarantee water supply even in years of drought. It was constructed in response to the worst drought in 100 years, which saw Sydney's dam storage levels approach 30 per cent in early 2007. 

The plant can produce an average of 250 million litres per day of drinking water. It was designed so that its capacity could be doubled if required to meet future needs.

Water conservation

Water conservation, including recycling water, makes our drinking water supply go further. Increasing water conservation efforts can delay the timing of investment in costly new supply infrastructure.

Water conservation allows us to reduce total demand in response to drought conditions or rising demand.

Water recycling

Water recycling involves treating and reusing wastewater, greywater and stormwater for use in and outside the home, in industry, for irrigation and agriculture.

Using recycled water helps preserve water stored in dams for drinking, reduces the impact of stormwater run-off on our waterways, and helps cool and green our urban environments.

This complex system is highly flexible and can be reconfigured during times of drought, high rainfall or during maintenance to enable the best quality water to be supplied to the community. Per capita water use in Greater Sydney has been declining since the 1990s  and our current total demand is approximately 100 billion litres per year lower than it was 25 years ago. This is despite a significant increase in population. Water use in 2015–16 was 530 billion litres.

During the Millennium Drought of the early 2000s, water use decreased significantly because of restrictions on water use and successful water conservation and efficiency campaigns. Water use has not returned to pre-drought levels due to a combination of factors, including the following water-saving programs:

  • Water Efficiency Labelling and Standards scheme (WELS).
  • Building Sustainability Index (BASIX).
  • Water Wise Rules.

With a prediction of rapid population growth in Greater Sydney and significant uncertainty around forecasts of per capita water use, we need ongoing monitoring of demand and flexible strategies so we can respond quickly if needed.

Challenges in securing water for Greater Sydney

What are the challenges?

Going forward

Increasing demand for water will place pressure on our water supplies

The population of Greater Sydney is expected to grow by more than two million people over the next 20 years, placing significant pressure on our water supply system.

Investing in water conservation and investigating new water sources for long-term needs are some of the strategies we will use to ensure that our water supply is secure and affordable.

Increasing urbanisation is impacting the liveability of our communities

Increasing density of urban living across many areas of the region can increase demand for water and impact waterway health.

Delivering the WaterSmart Cities program is one of our key strategies to ensure that our urban communities are more liveable and resilient.

Managing our variable climate and the impacts of climate change

A key challenge is to manage the uncertainty associated with our highly variable climate and the impacts of future climate change.

To make our water supply system more resilient to stresses and shocks we will ensure there is capacity in our supply system to manage extreme droughts and continue to build our knowledge on climate variability and climate change impacts.

Protecting the health of rivers impacted by dams

Warragamba Dam, on a tributary of the Hawkesbury-Nepean River, supplies more than 80 per cent of Sydney’s water. The presence of the dam has had an impact on the health of the river by greatly reducing the amount of water that flows to the downstream environment.

Introducing variable environmental flows from Warragamba Dam, and protecting the benefits of environmental flows, will complement a range of initiatives undertaken over the past decade to improve the health of the Hawkesbury-Nepean River.

Accompanied by monitoring and adaptive management, these strategies will help ensure that our rivers downstream from dams are healthy.

Providing cost-effective and sustainable water infrastructure to support growth

The water sector has had only a limited influence on decisions that affect the shape and density of cities.

A more integrated and whole-of-government approach to water infrastructure investment decisions is needed for the long term. This plan provides a range of strategies to improve the liveability and resilience of our urban communities.

Keeping the costs of water services affordable

Maintaining ageing infrastructure and servicing growth areas will require considerable investment in the future.

By making the best use of our existing supplies and investing in water conservation we can make sure that our water supply is secure and affordable.


Our water supply is secure and affordable

A secure water supply is essential for the Greater Sydney region to continue to grow and prosper.  By using a cost-effective mix of water supply and demand measures, we will ensure that water remains affordable and there is sufficient water to meet the region’s needs in drought and over the long term.

The plan comprises water supply and drought response measures including supply from dams, transfers from Tallowa Dam on the Shoalhaven River, the use of water from the Sydney Desalination Plant and the introduction of water restrictions. A broad range of drought supply measures are also included in the plan and will ensure the region has sufficient water to withstand a severe drought.

The plan also provides for an appropriate level of investment in water conservation to help achieve a secure and affordable water supply and to manage risks to water security from drought or rapidly rising demand.

At this time, a decision about the next major supply augmentation for Greater Sydney is not required. There is sufficient supply to meet demand over the next 10 years or more. In the future, all available supply options need to be considered so we can minimise costs and maximise the benefits of any new investment in water supplies. 

Drought response

Supply and drought response measures are implemented in a planned sequence and triggered as dam water storage levels drop.

Changes to the trigger levels in this plan make the best use of our existing water supplies and will save around $20 million on average compared to business as usual.

We also have a robust strategy to respond to droughts, including a number of options that could be implemented if severe drought conditions return to the region. 

Our water supply system is resilient to stresses and shocks

Resilience is the capacity of individuals, communities, institutions, businesses and systems within a region to survive, adapt, and grow – no matter what chronic stresses and severe shocks they experience.

The resilience of Greater Sydney’s water supply system is enhanced by large water storages that can cope with extended drought periods, maintaining an adequate buffer between demand and supply and having access to a diverse range of water sources, including water from the Sydney Desalination Plant and recycled water schemes.

We also have a robust strategy to respond to droughts much more extreme than any experienced over the past century. As part of the adaptive approach to securing supply, the plan provides for a drought options study to investigate the most suitable drought response measures for use in the event of an extreme drought. The best option(s) for supplying up to 100 million litres per day will be selected from a list of measures identified in the plan.

As the timing of the next drought is not known, more detailed studies on the available options will be undertaken when required. This approach will enable us to take into account advances in water supply technology, improvements in our understanding of future climate, and community views and preferences when making decisions about the best way to respond to the next drought.

As well as drought, other identified high-priority risks to water security include rapidly rising demand, supply interruptions, reduced system capacity and water quality problems. Rapidly rising demand will trigger increased investment in water conservation. To manage the other identified risks to water security, the trigger levels for supply and drought response measures can be altered on a short-term basis.

Due to significant uncertainties around climate variability and long-term changes in our climate, the plan takes an adaptive approach. The plan has strategies that can be deployed in response to changing circumstances, including additional investment in water conservation and additional or earlier implementation of drought supply measures. This adaptive approach to planning allows us to manage climate uncertainty in a way that acknowledges both potentially wetter and drier futures.

What makes our water supply more resilient?

Large storages: the water storages that supply the Greater Sydney region are large with over 2600 billion litres of water available when the dams are full. These large storages make the supply system robust enough to withstand extended periods of drought.

Ensuring an adequate buffer between demand and supply: the portfolio of supply and drought response measures meets a demand safely above current water use. We can also increase system capacity to meet increased demand by adjusting the trigger levels on our current measures and investing in water conservation to manage rapidly rising demand.

Diversity of sources: having access to alternative and diverse water sources such as water transfers from the Shoalhaven River, a range of dams, recycled water schemes in some areas, and the Sydney Desalination Plant means the system is better able to withstand shocks. 

A robust strategy to respond to droughts: our supply and drought response measures are triggered in sequence as dam storage levels drop, allowing the full storage capacity of all the dams to be used.  We also have a strategy to manage droughts much more extreme than any in the historical record.

Our urban communities are more liveable and resilient

A liveable region not only meets the basic social, environmental and economic needs of its people, it also addresses community values and preferences for amenity, wellbeing and a sense of place. Water is a key factor in making a place liveable and communities resilient. It meets people’s need for clean drinking water, underpins economic growth, helps cool and green our cities and contributes to healthy waterways.

The plan contains a suite of strategies designed to improve the contribution that water makes to the liveability and resilience of our urban communities in Greater Sydney. The key strategies are:

  • establishing the WaterSmart Cities program
  • investigating barriers and enablers to cost effective water recycling
  • establishing partnerships and collaborative arrangements between state agencies, local government and industry.

These strategies will build on and be coordinated with a range of government initiatives already underway or planned that will contribute to achieving the government’s goal of a liveable, growing and resilient Greater Sydney.

Establishing the WaterSmart Cities program

The new WaterSmart Cities program will help us explore opportunities to deliver drinking water, wastewater and stormwater services to new communities in a more integrated, cost-effective and sustainable way. By building integrated water solutions and cost-effective water recycling into new development areas, we can:

  • reduce future demand on drinking water supplies
  • help mitigate flooding risks
  • reduce pollutants entering our waterways
  • defer or avoid the need for major new water infrastructure.

Investigating barriers and enablers to cost-effective water recycling

We identified a range of pricing and regulatory issues that make it difficult to implement cost-effective recycled water initiatives. Many of the current pricing and regulatory settings can bias investment toward traditional servicing models, such as centralised water and wastewater networks. This occurs even where integrated solutions (including recycling) are shown to be as cost effective.

The plan recommends establishing an independent inquiry into barriers and enablers to the uptake of cost-effective water recycling, including consideration of potential regulatory and pricing reforms.

Establishing partnerships and collaborative arrangements

Opportunities for improved social, environmental and economic outcomes from water, wastewater and stormwater investment can be realised with state agencies, local government and industry working together.

To improve coordination, the plan allows for a working group to be formed to ensure programs are integrated and to avoid duplication of effort.

This will help us address current coordination gaps across government and between state and local government.

Rivers downstream from dams are healthy

A feature of the 2017 plan is the introduction of new variable environmental flows from Warragamba Dam to help protect and improve the health of the Hawkesbury-Nepean River. This is part of a program of work over the past decade to improve the health of rivers impacted by dams in the Greater Sydney region.

The release of variable environmental flows from Warragamba Dam will enhance the community’s use of the river for boating, fishing and swimming. It will reintroduce more natural flow conditions, which will help improve water quality, reduce problems caused by excessive growth of floating aquatic weeds, and support the growth of fish populations.

It is important that the benefits of environmental flows are not eroded over time because of the impacts on the river from wastewater discharges as our population grows, as well as the increased sediment and nutrient loads entering our river systems from urban development. To protect the benefits of the flows the plan identifies a number of strategies including coordination of government efforts to help reduce the impact of nutrients and pollutants on the Hawkesbury-Nepean River, managing the amount of water extracted from the river downstream of the dam, and monitoring and adaptively managing the flows for the best possible outcomes.

Environmental flows mimic natural flows

Environmental flows are designed to mimic the patterns of a natural flow regime and support a river’s ecology. They are released to help improve water quality, fish passage and reduce floating weeds.

Variability in flow is a natural part of Australian rivers, with ecosystems evolved to cope with our variable climate. In dry weather or during drought there would be little water in a river.

In wet weather, river flows are much higher. Plants and animals in and around the river have evolved with this pattern of dry and wet. No flows or steady, low flows below dams contribute to poor water quality, invasive floating weed outbreaks, toxic algal blooms and impact adversely on the native fish population.

An adaptive plan is better able to support a liveable, growing and resilient Greater Sydney

The Metropolitan Water Plan was first developed in 2004, then reviewed in 2006 in response to a severe drought. It was revised again in 2010 as part of a regular schedule of review.

The 2017 plan was developed by Metro Water in collaboration with water utilities and state agencies, key industry stakeholders and the community.

The review was undertaken in line with the National Urban Water Planning Principles adopted by all Australian governments in 2008.

The plan is based on a solid foundation of technical studies, independent reviews, hydrological modelling and economic analyses, community and stakeholder engagement activities, and social surveys.

The plan comprises a suite of strategies that build on work undertaken as part of previous plans, new programs and initiatives that will be rolled out over the next several years, and actions that will be taken should drought conditions return. An implementation guide provides a summary of the strategies in the plan, associated actions and the timeline (where relevant) for implementation.

Monitoring and evaluation are essential tools for the implementation and ongoing improvement of the plan. In a process of continuous improvement, the latest and most robust information will be used to assess if the plan is meeting its objectives and to make timely decisions on how best to adapt to incorporate the latest knowledge, experience and technology.

The plan’s outcomes will be monitored regularly, and the plan will be subject to a full review no later than 2022.