Climate change is the biggest challenge faced by Water Corporation.

It is a global issue that is impacting WA’s water supply and our way of life. The impacts are felt across the world, Australia, and throughout WA in our communities, businesses, farms and homes.

Rainfall has dramatically decreased in many areas of our state. The amount of streamflow to our dams generated from each millimetre of rainfall continues to decline.

Infographic showing the changes in our water sources since 1960

Infographic showing the changes in our water sources since 1960

What this means

As a community here in Perth we must continue our efforts to save water and adapt to what climate change is doing to our environment.

We have had to respond to this challenge and adapt the way we deliver water to WA in order to preserve our unique lifestyle, by working towards long-term targets outlined in our Water Forever plan, first published 10 years ago. Our strategic focus areas include:

  • Investing in climate resilient water sources such as desalination, groundwater replenishment and water recycling.
  • Focussing on innovation, we are committed to reducing our environmental footprint by reducing our energy consumption and embracing renewable sources.
  • Inspiring positive action in our community to adopt waterwise practices and drive water efficiency improvements.

More on our response to climate change

Our water overview

We need steady, regular rain in order to soak our catchments and get water flowing into our dams. Slowly declining rainfall means Perth's dams receive much less streamflow than in past years.

Updated: Wednesday, 30 September 2020



268 GL

Last year


284 GL



-16.2 GL

To 9am



May total

May average*





* Average monthly rainfall (for the period 1876 - 2016).

How climate change has impacted our water sources

Water sources for our largest scheme, the Integrated Water Supply Scheme (IWSS), have changed dramatically. Water for the IWSS is now comprised of a combination of sources, including desalinated seawater, groundwater, groundwater replenishment and streamflow into dams.

Traditionally, Perth relied heavily on streamflow into our dams as a water source, but declining streamflow has meant dams now play a bigger role as storage reservoirs. The water in our dams is no longer just made up of inflows from rain. Groundwater and desalinated water are stored in these dams during periods of low demand so it is available when it is most needed in the hotter months.

See how our climate has changed

In 2019-20 the breakdown of our IWSS water sources consisted of:

Desalination icon
Groundwater icon
Dams icon
Groundwater replenishment icon
Groundwater replenishment

Climate change news

16 Sep 2020 | Media Release

Near record low rainfall to end of winter prompts Perth waterwise reminder

Low rainfall to the end of August is another stark reminder for Perth residents of the ever-increasing need to stay waterwise in the face of climate change - following one of the city's driest and warmest winters on record.

  • Climate change
  • Leaks
  • Water sources
  • Waterwise
04 Sep 2020 | Media Release

Perth metro weekly water update

Latest water use, dam levels, streamflow and rainfall data

  • Dams
  • Climate change
  • Water sources
31 Aug 2020 | Update

Saving water is all in a day’s work for our waterwise platinum winners

Ocean Keys Shopping Centre and Perth Zoo have both been awarded 2020 Platinum Waterwise Business of the Year. Both businesses have shown an outstanding commitment to improving their water efficiency.

  • Waterwise
  • Community
  • Climate change
Perth Zoo Mainlake Enclosure area