Water Planning for Sydney
Water planning for Sydney

Water for people and water for the environment

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Frequently Asked Questions

Why do we need a water plan for greater Sydney?

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, which in turn places additional pressure on our water supplies.

To add to this pressure, urbanisation also has impacts on our local communities’ water needs and waterways. An increasingly variable and changing climate means that we cannot know with certainty how much rainfall will support our water supply system in the future.

The 2017 Metropolitan Water Plan is the NSW Government’s response to these challenges and pressures. The plan’s overarching goal is to secure water for a liveable, growing and resilient greater Sydney. It establishes key strategies to be implemented over the life of the plan, and beyond this, will set us on a pathway towards a water supply system that meets greater Sydney’s needs for the next 50 years.

What is the Metropolitan Water Plan and how is it developed?

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.

Following an extensive review period, the 2017 plan was developed by Metro Water in collaboration with water utilities and state agencies, key industry stakeholders and the community.

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.

Our strategies will help inform government decisions in relation to future water infrastructure investment and will guide the strategic planning to deliver the regional plan for greater Sydney and districts plans.

What are the key elements of the 2017 Metropolitan Water Plan?

The highlights of the Metropolitan Water 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.

Who is responsible for developing and implementing the Metropolitan Water Plan?

The Metropolitan Water Directorate (Metro Water), within the NSW Department of Primary Industries – Water, led and coordinated this metropolitan water planning for greater Sydney. Metro Water convened the teams of technical experts and decision makers who developed the strategies of the plan. The review is also overseen by an Independent Water Advisory Panel.

Metro Water also engaged 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.

A detailed monitoring, evaluation, reporting and improvement plan is being developed by Metro Water to guide and support implementation of the Metropolitan Water Plan.

How much water do we use?

Water use in greater Sydney has declined since 2002 and our current total demand is approximately 100 billion litres per year lower than it was 25 years ago. This is despite a significantincrease 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.

Where does our water come from?

Most of the region’s water is supplied from dams that store rainfall runoff from a large catchment area.

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 to where it is needed most. 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.

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.

How is water secured for greater Sydney?

Drinking water for the people of the greater Sydney region is secured through a mix of water supply and demand measures. These measures are deployed in a planned sequence as dam storage levels fall.

As part of the 2017 Metropolitan Water Plan,  trigger levels for the supply and drought response measures (set as a percentage of total dam storages) have been revised to secure our water supply and enable it to be operated at least-cost to the community. These supply and drought response measures are implemented in a planned sequence and deployed as dam water storage levels drop.

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. These include the second stage of the existing Sydney Desalination Plant, using groundwater, using temporary desalination plants, building a new regional desalination plant, and using recycled water for drinking (depending on community views). At this stage recycled water is used for non-drinking purposes only, and its future use will depend on community attitudes and acceptance.


How does Sydney Desalination Plant support our water supply system?

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, equivalent to 17 per cent of Sydney's current water demand. It was designed so that its capacity could be doubled if required to meet future needs.

How does the Metropolitan Water Plan respond to our variable climate and potential climate change impacts?

We have a highly variable climate, with prolonged and severe droughts followed by periods of high rainfall. Despite significant analysis there is a high degree of uncertainty about the impacts of climate change on our water supplies and future demand for water.

During the review period we studied and modelled the expected impacts of climate change across the greater Sydney region and its catchments as part of a larger study across NSW.

The plan takes an adaptive approach by identifying 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 ensures there is capacity in our supply system to manage extreme droughts and continue to build our knowledge on climate variability and climate change.

Additional studies will be undertaken in the next plan review period to better understand the impacts of climate variability and climate change on the existing water supply system.

What is the plan doing to help develop liveable and resilient urban communities?

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 and defer or avoid the need for major new water infrastructure.

What is a variable environmental flow?

Environmental flows (e-flows) are planned releases of water from dams or weirs that help to reduce the impact of those structures on the river downstream.  E-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.

What is being done to help improve the health of the Hawkesbury-Nepean River?

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 downstream. This is part of a program of work over more than a decade to improve the health of rivers impacted by dams in the greater Sydney region.

Flows into the dam will be measured, and a proportion of this released each day. This means that the e-flows will mimic the natural variation in river flows.

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

What is water recycling and what role does it play in this plan?

Water recycling is treating and reusing wastewater, greywater and stormwater for non-drinking purposes in and outside the home, in industry, for irrigation and agriculture. Using recycled water and harvested stormwater is a great way of saving our valuable drinking water and it can delay the need to invest in new supply infrastructure.

In 2010, use of recycled water was saving about 33 billion litres of water a year that might otherwise come from our drinking supplies. By 2015 there was capacity for around 63 billion litres of water to be recycled for use in commercial and industrial premises, sporting fields and in some residential developments for toilet flushing and garden watering. Visit https://www.metrowater.nsw.gov.au/planning-sydney/recycling for more information on recycling projects in the Sydney region.

Removing barriers and facilitating investment in cost effective recycled water projects is a key focus of the updated Metropolitan Water Plan, and the NSW Government will continue to investigate new and innovative ways to utilise recycled water to address water security risks, improve the amenity of our local communities and contribute to waterway health.

Is water conservation still a focus of the Metropolitan Water Plan?

The 2017 Metropolitan Water Plan includes a new approach to investing in water conservation, based on a requirement in Sydney Water’s recently revised operating licence. Sydney Water is required to develop a water conservation program based on investing in programs up to an economic level of water conservation (ELWC). The ELWC is when the benefits from water conservation activities are equal to the costs. This will take into account the costs and benefits to Sydney Water, customers, and the environment when water conservation projects are assessed. The ELWC will include leakage, recycling and demand management as well as supply and demand options to ensure best value water security for customers in the long term. For more information visit the Sydney Water website.

Where can I go for more information?

For further information about the Metropolitan Water Plan for greater Sydney visit www.metrowater.nsw.gov.au and yoursaymetrowater.com.au/MWP