Strategies to rebalance Gnangara - Alternative sources

We are introducing alternative water sources to rebalance the Gnangara groundwater system in a drying climate by 2032.
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Over time, introducing alternative water sources will take pressure off Gnangara groundwater and build climate resilience for businesses and the community.

Boosting water supplies

The Water Corporation already has two seawater desalination plants, which can provide up to 50 per cent of the metropolitan area’s scheme water needs. A new desalination plant is being built at Alkimos, expected to be operational in 2028. Desalination has and will continue to give us a secure water source for part of Perth’s drinking water supply that doesn’t depend on the rain.

Groundwater replenishment where large volumes of highly treated recycled water are recharged back into deep aquifers to augment our drinking water. Construction of Perth’s first full-scale Groundwater Replenishment Scheme at the Beenyup facility in Craigie is now complete with a capacity to recharge up to 28 GL of recycled water into groundwater for storage and abstraction each year.

Managed aquifer recharge where water is infiltrated back into an aquifer through reinjection bores or ponds, basins and trenches for later use or to benefit the environment. Well considered location and design can deliver benefits for local water users and the environment.

Stormwater harvesting where rainfall runoff is captured in tanks or other storages as a water source that can improve water supply for non-drinking purposes in households or businesses and parks and gardens. Good urban design can enhance stormwater recharge to groundwater – a natural form of stormwater harvesting.

Wastewater treatment and reuse where wastewater is recycled to be used for irrigation of parks, public gardens and golf courses, and potentially other uses such as horticulture and industry.

The best alternative, non-potable supply may vary from place to place, and interested water users will need to carefully assess the range of options available and the costs and benefits of each.

Read about the other ways we are Securing the future of Gnangara groundwater.

Smarter solutions for recycled water

The City of Kalamunda is recycling winter drainage water, storing it through managed aquifer recharge, and using it to irrigate parks in summer.

In response to reduced groundwater availability and local salinity issues, the Western Suburbs Regional Organisation of Councils investigated new ways of using recycled water to irrigate parks and public open space either directly from the Subiaco treatment plant or by ‘topping up’ the Superficial aquifer for reuse later.

The Department of Water and Environmental Regulation is also partnering with the Department of Communities, the City of Swan and developers to consider water supply options for the Department of Communities’ Brabham development in Perth’s north-east.