- Serpentine groundwater allocation limits have been reviewed and updated in response to climate change
- The revised allocation limits will not impact existing water licence holders
- Updated allocation limits will protect groundwater-dependent ecosystems and strengthen local water security.
Serpentine groundwater allocation limits have been revised in response to ongoing declines in groundwater levels due to reduced rainfall caused by climate change.
The updates are contained in the new Waangaamaap - Serpentine Groundwater Allocation Statement released today.
The updated allocation limits will reduce the available groundwater in most of the Superficial and Leederville aquifer resources. The new allocation limits factor in the entitlements of existing water licence holders, by ensuring they will not be affected by the changes.
Climate change has caused a significant reduction in rainfall in the Serpentine groundwater area, which is located approximately 30 kilometres south of Perth.
Average annual rainfall in the area has declined by about 10 per cent since 1975. During the period 1945-1974 average rainfall was 870 mm/year, while between 1975-2022 it dropped to 780mm/year. As a result, rainfall recharge to groundwater in the area is now significantly less. Future climate projections for the area show average annual rainfall could fall to 680mm/year beyond 2030.
The majority of licensed groundwater use in the Serpentine groundwater area is for agricultural purposes - including irrigation of pasture, vegetables, intensive stock raising, and nurseries. Groundwater is also used for the irrigation of parks, ovals and other public open space areas.
The revised allocation limits will support improved water security for local water users, as well as the protection of our important wetlands and bushland. These natural ecosystems are important to the communities in the region, and the continuing culture of the Bindjareb Noongar people.
The Waangaamaap - Serpentine Groundwater Allocation Statement is part of the State Government's Kep Katitjin - Gabi Kaadadjan - Waterwise Perth Action Plan 2 which aims to establish leading waterwise communities for Boorloo (Perth) and Bindjareb (Peel) by 2030.
For more information on the Waangaamaap - Serpentine Groundwater Allocation Statement please visit wa.gov.au/government/publications/waangaamaap-serpentine-groundwater-allocation-statement
Comments attributed to Water Minister Simone McGurk:
"Adjustments to water availability to address reduced rainfall and climate change are essential to protect our precious groundwater resources.
"The updated allocation limits will support sustainable groundwater use in the Serpentine region as our climate continues to become drier and hotter.
"Though these changes will not impact the licences of existing groundwater licensees, the new Waangaamaap - Serpentine Groundwater Allocation Statement strongly signals the need to meet future water demand through improved water use efficiency, trading, and in some cases alternative water sources."
