Perth metro weekly water update – 3 January 2020






January water use to date

3 billion litres

3 billion litres

Dam storage levels


48 per cent

Weekly streamflow into dams


44 billion litres

January rainfall to date

16.7 mm

(January average rainfall 1994-2017)

1.60 mm

Note: 1 billion litres = approx. 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 973 million litres per day, which was below the forecast of 1032 million litres.


Daily water use for the last five days


Actual water use (million litres)

Forecast (million litres)
















Note: water use is calculated up to 8am each day for the previous 24 hour period


Since 1 July 2019, we have used 144 billion litres of water – which is 7 billion litres over the forecast for this period.


Dam level (total for 15 dams)

The dam storage levels have dropped slightly this week and are sitting at a combined 47.5 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 2019 the dams have received 44.1 billion litres of streamflow.  The post-1975 average for the May to April period (called the streamflow year) is 183.9 billion litres.


Sprinkler roster compliance


The two-day a week sprinkler roster now applies. Throughout 2019, we took a total of 9408 actions (warnings + fines) compared with 8684 actions for 2018.


Annual rainfall


Perth has received 1.60 mm of rainfall since 1 January 2019. The average (1994-2017) rainfall for the January period is 16.7 mm.


General water news


We are reminding everyone living in bushfire prone areas to not rely on scheme water supplies during a bushfire if you plan to stay and defend your home.


Water Corporation will do all it can to maintain scheme water during a bushfire but heat-damaged infrastructure, or a cut to power, may result in a loss of supply. High demand for water will also lead to a drop in water pressure and water supply tanks will empty quickly.


Residents who plan to defend their home in the event of a bushfire must ensure they have an independent water supply, and a pumping capability in the event of a total loss of power.


To find out how to prepare for a bushfire, including having an independent water supply, visit:


Media Enquiries:

Contact: Clare Lugar

Position: Manager Media and Strategic Communications

Phone: (08) 9420 2555