Table showing target and actual water use, dam levels, streamflow and rainfall
Target Actual
December water use to date 10.8 billion litres
10.3 billion litres
Dam storage levels N/A 49.2 per cent
Monthly streamflow into dams N/A 0.73 billion litres
December rainfall to date 13.1mm (December average rainfall 1876-2016) 0.40mm
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 982 million litres per day, which was below the forecast of 984 million litres.

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)
11/12/2020 1,066 993
10/12/2020 1,020 993
09/12/2020 1,070 993
08/12/2020 998 993
07/12/2020 946 970
Note, water use is calculated up to 8am each day for the previous 24 hour period.

Since 1 July 2020, we have used 114.44 billion litres of water – which is 2.56 billion litres below the forecast target for this period.

Dam levels (total for 15 dams)

The dam storage levels have decreased slightly this week and are sitting at a combined 49.2 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 2020 the dams have received 42.9 billion litres of streamflow. The post-1975 average for the May to April period (called the streamflow year) is 176.73 billion litres.

Sprinkler roster compliance

Since 1 January 2020, we have taken a total of 5,485 actions (warnings + fines) compared with 8,959 actions for the same period in 2019.

Annual rainfall

Perth has received 673.8mm of rainfall since 1 January 2020. The average (1994-2019) rainfall for the same period to the end of November is 727.2mm.

General water news

With another challenging bushfire season predicted, the Minister for Water this week reminded the community not to rely on their mains water supply if they plan to stay and defend their property during a bushfire.


While leaving high-risk bushfire areas is the safest option, those planning to defend their home must have an independent water supply such as water tanks and pumping capability in the event of power loss.


Bushfires are unpredictable but the single biggest killer is indecision. The Department of Fire and Emergency Services’ new My Bushfire Plan website and mobile app guides users through the creation of a plan that can be completed in minutes. The app is available from the App Store, Google Play or


Read more in the Minister’s media statement.