Expanded desalination plant to help secure Pilbara's water supply

The Western Australian Government has announced a $606 million investment to double the capacity of the $1.1 billion Dampier Seawater Desalination Plant.

Stage 1 is being built by Rio Tinto. With the addition of Stage 2, the expanded plant will now supply eight billion litres of water to the Pilbara annually, including providing drinking water to more than 10,000 homes in Karratha, Wickham, Roebourne and Point Sampson.

The project will also allow Rio Tinto and Water Corporation to reduce groundwater abstraction from the Bungaroo and Millstream borefields, protecting culturally and ecologically significant sites.

Stage 1 is already under construction, with the additional investment allowing expedited delivery of a Stage 2 to be online in 2027.

The government’s investment in expanding DSDP’s capacity follows a $12.4 million investment made last year to support long-term sustainability of the Millstream aquifer via a partnership between Water Corporation, Yindjibarndi Aboriginal Corporation, and the Department of Water and Environmental Regulation.

Water Corporation will continue working closely with Traditional Owners to maximise their involvement as DSDP’s expansion progresses. To further support long-term water security, Water Corporation will also make changes to sprinkler rosters in the City of Karratha from 1 April.

As part of a six-month trial, households in Karratha, Roebourne, Dampier, Wickham, and Point Samson will be allowed to use sprinklers three days per week, reducing their overall usage by one day per fortnight.

The decision was informed by expert advice and is part of broader efforts to respond to the effects of climate change on West Pilbara water sources.

“This investment…is a significant step in safeguarding long‑term water security for West Pilbara communities, while also creating the foundations for sustained economic growth and future development across the region,” said Water Minister Don Punch. “Reduced rainfall is placing increasing pressure on both our surface water and groundwater systems, as well as the ecosystems and cultural landscapes that rely on them.

“Ensuring a reliable, sustainable water supply is critical not just for households and industry, but for the health of Country.”

“We understand water is a scarce resource, especially in the Pilbara,” said Rio Tinto Iron Ore Chief Executive Matthew Holcz. “Bringing on the Dampier Seawater Desalination Plant is an important step as we work to reduce our reliance on groundwater abstraction.

“We are pleased to partner with the Western Australian Government to improve the security and sustainability of water supply throughout the Pilbara.”

Image credit: Rio Tinto