Table showing target and actual water use, dam levels, streamflow and rainfall
Target Actual
August water use to date

11.8 billion litres

12.7 billion litres
Dam storage levels N/A 58.6%
Monthly streamflow into dams N/A 38.21 billion litres
August rainfall to date 132.90 mm (August average rainfall 1876-2016) 46.40 mm
Note: 1 billion litres = approximately 400 Olympic swimming pools. Please note the figures in this table are rounded (except for rainfall) to the nearest whole number.

Water use 

Average water use over the past week was 652 million litres per day – above the demand forecast of 592 million litres per day.

Daily water use for the last 5 days

Table showing daily water use for the last 5 days
Date Actual water use (million litres) Forecast water use (million litres)
20/08/2021 601 595
19/08/2021 628 595
18/08/2021 643 595
17/07/2021 712 595
16/07/2021 670 588
Note, water use is calculated up to 8am each day for the previous 24 hour period.

Since 1 July 2021 to date, we have used 31.29 billion litres of water – which is 1.69 billion litres above the forecast target for this period.

Dam levels (total for 15 dams)

The dam storage levels are slightly up on last week and are sitting at a combined 58.6 per cent* of full capacity.

*Please note some dams are filled from different sources - dam levels include the transfer of groundwater and desalinated seawater from treatment plants as well as streamflow (that comes from rainfall). As we use many different sources of water, dams are no longer an accurate indicator of the health of Perth's overall water supply situation.

Streamflow (total for 15 dams)

From 1 May 2021, the dams have received 66.6 billion litres of streamflow. The post-1975 average for the May to April period (called the streamflow year) is 175.59 billion litres.

Sprinkler roster compliance

Since 1 January 2021, we have taken a total of 4,290 actions (warnings + fines) compared with 4,102 actions for the same period in 2020.

Annual rainfall

Perth has received 645.2 mm of rainfall since 1 January 2021. The average (1876-2016) rainfall for the same period to the end of August is 676.5 mm.