What's our goal for Gnangara groundwater?

Our goal is to rebalance the Gnangara groundwater system by 2032 to secure our lowest cost and most accessible water source for Perth and to support a healthy environment.

Learn about the Gnangara groundwater allocation plan: draft for public comment below.

The Gnangara groundwater allocation plan: draft for public comment is part of the State Government’s response to climate change.

The plan sets out how Gnangara groundwater use will be reduced over the next 10 years:

  • Taking less groundwater will rebalance the groundwater system to better match less rainfall in a drier climate, ensuring healthier wetlands and vegetation and a secure water supply for Perth in the long term.
  • The plan proposes a reduction shared across all groundwater users:
    • A 27 per cent reduction (30 gigalitres per year) in 2028 to groundwater licensed to the Water Corporation for Perth’s Integrated Water Supply Scheme (drinking water).
    • A 10 per cent reduction for most groundwater licensees from 2028, to give people time to adjust to the changes.
    • Alignment of the sprinkler roster for garden bores and scheme users from September 2022 – State Government is proposing that all households across Perth and Mandurah will have a two-days-per-week sprinkler roster between 1 September to 31 May each year, regardless of the water source.
  • More information on reductions for different water users is in the Summary and Chapters 4 and 5 of the draft plan. Schools and hospitals will be exceptions to reductions.

The plan sets groundwater level objectives to protect important groundwater-dependent ecosystems, such as wetlands and bushland areas, and outlines how we will continue to monitor water levels, water quality and ecological health against these objectives to ensure the delivery of real outcomes.

The plan was open for public comment until 5pm Monday, 28 February 2022.

For further information on the plan, contact us at

Better water outcomes are more achievable if we work together. There are great examples of this across different industries.

We encourage you to speak with peak bodies and others in your industry about the draft plan and how you can adapt to less groundwater availability over the coming years.