Rio Tinto Group (ASX:RIO) partnered with the Western Australian Government in a 50:50 joint venture to complete stages one and two of the Dampier seawater desalination plant, the mining company said in a statement on Wednesday.

The plant is expected to deliver 8 gigaliters of desalinated water per year to the West Pilbara Water Supply Scheme, which supplies Karratha, Wickham, Dampier, Roebourne, Point Samson, as well as the Cape Lambert and the Burrup Peninsula industrial areas, the statement said.

The first stage of construction will start delivering 4 gigaliters of annual desalination capacity this year, while the second stage, which will add a further 4 gigaliters, is anticipated to deliver the first water in 2027, per the statement.

Rio Tinto shares fell 1% in afternoon trade on Wednesday.