Perth Seawater Desalination Plant

The Perth Seawater Desalination Plant, located in Kwinana, produces 45 billion litres of fresh drinking water a year – around 18% of Perth’s water supply.

The Perth Seawater Desalination Plant (PSDP) has been producing drinking water since November 2006. It plays a vital role in securing water supply for the Integrated Water Supply Scheme (IWSS), which supplies the metropolitan area and some parts of the South West and Goldfields.

Protecting the ocean environment

We are dedicated to protecting the sensitive marine environment of Cockburn Sound. We undertake comprehensive marine monitoring and work closely with local groups to ensure the health of the Sound is maintained. 

Each year the marine infrastructure is inspected by divers to ensure it is operating as designed and marine growth is not impeding flow rates. Over the years it has become evident that the 40 port diffuser system provides structure and stability in an otherwise sandy seafloor, and supports a diverse and abundant marine community.

Underwater footage from the plant

Flora and fauna rehabilitation

In partnership with the Perth Region Natural Resource Management group, staff at PSDP undertake regular planting of native shrubs in the dune area. This has helped to stabilise the dune system, preventing erosion and encouraging native fauna back to the area. 

Through the partnership, habitat boxes are being installed through the dune area to protect native fauna from feral animals which also inhabit the area.

Infrared photos of a Brown Goshawk owl and a pair of White Browed Scrub Wrens spotted at the PSDP site

Photo: Infrared photos of a Brown Goshawk and a pair of White Browed Scrub Wrens spotted at the PSDP site.

The plant also holds an annual clean-up of rubbish on the stretch of beach adjacent to the plant. A marked reduction in the volume of rubbish collected has been observed over the years.


The plant has won numerous national and international awards including the International Desalination Association’s International Desalination Plant of the Year in 2007.

Marine monitoring 

As part of our operating licence issued by the Department of Environment Regulation and conditions & commitments specified in Ministerial Statements 655 and 832 issued by the Office of the Environmental Protection Authority, comprehensive monitoring is conducted to ensure there are no adverse environmental impacts on the marine environment from our operations.

Annual compliance assessment report 2016–17

We undertake continuous, real-time water quality monitoring of water entering and leaving the plant, in addition to routine marine monitoring at various locations in Cockburn Sound and regular performance tests on the diffuser system to ensure it is performing as required.

We continue to work closely with the Cockburn Sound Management Council and support their ongoing environmental monitoring and annual reporting requirements. Water Corporation is an active member on the CSMC Reference Group and Kwinana Industries Council.

Underwater photos

Inspections show a variety of fish, crabs, octopus, seahorses, mussels, barnacles, sponges, algae and hard and soft corals colonising the outfall.

All photos were taken by Fremantle Commercial Diving on behalf of Water Corporation.