Perth dams receive more streamflow

The Integrated Water Supply Scheme delivers water to Perth, parts of the south west, Agricultural and Goldfields regions.  More than two million people are connected to the Scheme who together used an average of 580 million litres of water per day last week.  This is more than we would expect to supply at this time of year (564 million litres per day). 

The Winter Sprinkler roster is in place between 1 June and 31 August. In total this week we issued 98 warnings and 28 infringements in the metro region.  This is compared to 96 warnings and 30 infringements last week.  Please keep your sprinklers switched off.


There has been some reasonable rainfall this week, which brings the annual total since 1 January to 565.60mm. This is below the average (678mm) for the same period.


Perth’s dam storage levels increased from 32.5% to 33.6% (1.1 percentage points) over the last seven days. That equates to an increase of 7.4 billion litres – to put this into perspective we use over one billion litres of water each day at the height of summer.  It is important to note Perth’s dam levels may increase by…


  1. rainfall that falls over the top of them
  2. streams that collect water from the areas surrounding the dams, and then flow into the dam itself (streamflow)
  3. if the water table below the dam rises to a high enough level


During winter, when our customer’s water use is lower, we also transfer water into Perth’s dams from desalination and groundwater sources.  Last winter we transferred 22 billion litres of water into dams from desalination and groundwater.

Over the last seven days we have received 8.04 billion litres of streamflow into Perth’s dams. 


The post-1975 average for streamflow for the period 1 May to 31 August is 65 billion litres.   

Information on how to save water is available at

Media Enquiries:

Contact: Clare Lugar

Position: Water Corporation spokesperson

Phone: (08) 9420 3043