Find out about the changing role dams are playing in our water supply.

Traditionally, Perth has relied heavily on streamflow into our dams as a water source. But today, this streamflow supplies only 10% of the water used in our Integrated Water Supply System (the scheme that supplies water to Perth, Goldfields and some of the South West).

Why is it so low? 

Years of below-average rainfall means that in some part of WA, we no longer receive enough rainfall to generate streamflow to fill our dams. 

Streamflow is the amount of water entering our dams from our catchments, areas where water is collected by the natural landscape. 

Watch our video to find out more:

Read a transcript of this video (new window)

Read more about the impact of climate change on catchments

The role of dams in regional areas

Water source

Positive rainfall and stream flow trends in some areas of the North West mean many towns in the Pilbara and Kimberley regions will continue to be supplied by traditional surface water and groundwater sources. 

Increasing connectivity for security and flexibility

In recent years we have connected more of our southern dams.

This provides greater flexibility and security to Perth and the South West, as it allows towns’ access to a wider range of water sources.

Moving water around

We also use dams to move water around, including supplying towns in the Goldfields and Agricultural areas through the CY O’Connor Goldfields Pipeline.

North Dandalup Dam