Rio Tinto and the Western Australian Government have established a 50:50 joint venture to deliver both Stage 1 and Stage 2 of the Dampier Seawater Desalination Plant, a major project intended to strengthen water security in the Pilbara region.
When fully operational, the facility will supply 8 gigalitres (GL) of desalinated water annually to the West Pilbara Water Supply Scheme, helping reduce reliance on local groundwater resources. The scheme, operated by Water Corporation, provides water to the towns of Karratha, Wickham, Dampier, Roebourne and Point Samson, as well as the industrial areas of Cape Lambert and the Burrup Peninsula.
The A$1.1 billion desalination facility will be operated by Rio Tinto and is intended to reduce pressure on groundwater resources
Construction of the plant’s first stage is already underway and is expected to provide 4GL of desalinated water per year later in 2026. Work on Stage 2 has also begun and will add another 4GL of annual capacity, with first water anticipated in 2027. Together, the two stages are expected to significantly lower abstraction from the Bungaroo and Millstream aquifers.
The partnership follows a Memorandum of Understanding signed in 2025 between the state government and Rio Tinto aimed at improving water security across the Pilbara.
Over the past five years, the West Pilbara has experienced rainfall and streamflow levels frequently below the long-term average, limiting groundwater recharge at the Millstream and Bungaroo aquifers that supply the regional system. Groundwater abstraction has been a particular concern for Traditional Owner groups.
The A$1.1 billion (about US$770 million) desalination facility will be operated by Rio Tinto and is intended to reduce pressure on groundwater resources while helping protect areas of environmental and cultural significance.
Western Australian Premier Roger Cook said: “We are investing hundreds of millions of dollars in a project that will deliver billions of litres of water to local households and businesses. This project shows why our government’s Made in WA plan is so important to our State’s future and how it is helping deliver our priorities.”
Rio Tinto Iron Ore Chief Executive Matthew Holcz said: “We understand water is a scarce resource, especially in the Pilbara. Bringing on the Dampier Seawater Desalination Plant is an important step as we work to reduce our reliance on groundwater abstraction.
“Stage 1 of the Dampier Seawater Desalination Plant will reduce our draw on the Bungaroo aquifer, which we recognise is deeply important to the Robe River Kuruma People. We are pleased to partner with the Western Australian Government to improve the security and sustainability of water supply throughout the Pilbara.”
