Perth: Key findings

For the water account period 1 July 2019–30 June 2020

  • A relatively dry winter in 2019 resulted in low streamflows across the region.
  • Surface water storage dropped to 41% full, the first annual drop in four years.
  • Consumptive water use was 801 GL, similar to the previous year.

Climate and water


Rainfall icon

575 mm

below the average of 795 mm


Streamflow icon

below average

during the entire year


Storage icon

41% full


13% less than last year

Water use

Water sourced

Graph showing breakdown of water sources used in the Perth region. A total of 801 GL of water was used in the region in 2019–20. Groundwater made up 65% of total water sourced. Desalinated water made up 19%, surface water 17%, and inter-region deliveries less than 1% of the water sourced.

Water supplied

Graph showing breakdown of water users in the Perth region. A total of 801 GL of water was supplied to users in 2019–20. 54% of total water supply was for individual users. 37% was for the urban system and 9% was for the irrigation scheme.

Water status


860 GL

total surface water and groundwater allocations

Water assets

392 GL

water assets at 30 June 2020

64 GL less than last year



storage levels expected at 30 June 2021 to last year