Pilbara regional water supply strategy: a long-term outlook of water demand and supply

Strong growth in the resource sector has seen more water being abstracted at mine sites in the inland Pilbara region and hence an increased volume of dewater surplus to the mine requirements. At the same time, resource sector growth has driven an increase in water demand at the coastal towns and ports due to a growing population, service industries and dust suppression requirements.

The state government’s Pilbara Cities initiative is building on mining sector growth to diversify the economy, grow the population and provide liveable towns and cities in the Pilbara. The Department of Water is working to support this vision by investigating and planning for the water supply options that will be needed during the next 30 years and beyond. The Department of Water’s modelling and assessment has clarified the reliable supply of the water resources needed for short-term water demands for the West Pilbara area (Karratha and surrounding towns and ports), Port Hedland and Onslow. As a result, new water supplies are being developed by industry and the Water Corporation. These are:

• a 10 GL/yr borefield in the Lower Bungaroo Valley being developed by Rio Tinto Iron Ore to supply their port operations in the West Pilbara area. This will enable supply from the Millstream borefield to be wholly available for town water supply
• Yule and De Grey borefield expansions by the Water Corporation1 to supply an additional 5 GL/yr to Port Hedland
• Cane River borefield expansion by the Water Corporation to provide an additional 0.2 GL/yr, and a new desalination plant (seawater or brackish groundwater) being developed by Chevron to provide a further 0.6 GL/yr to Onslow.

This water supply strategy looks beyond these developments to provide early assessment and support further planning for new water supplies in the medium and long-term. It focuses on the three coastal schemes, but also provides an overview of regional water demand and supply.