A critical piece of infrastructure for Western Australia's multi-billion dollar water future has now been laid underground, marking a significant step forward for the state's next major desalination plant.
Powering Perth's Future Water Supply
Workers have successfully installed a 5-kilometre underground high-voltage cable connecting the future Alkimos Seawater Desalination Plant site to the existing Yanchep substation. Western Power recently completed the complex task of laying the 132kV line, which will provide the essential electricity needed to run the massive facility.
Craig Julian, Western Power's head of major works, described the project as challenging, citing difficult rocky terrain and the need to coordinate with heavy construction traffic on site. "The site is under significant construction, which meant ensuring we could drill safely under an access track used by 80-tonne trucks," Mr Julian explained.
The close collaboration between Western Power and the Water Corporation was designed to align with a long-term strategy to power desalination plants using renewable energy, supporting the utility's commitment to net-zero emissions by 2035.
A Project of Immense Scale and Importance
The $2.8 billion Alkimos Seawater Desalination Plant (ASDP) represents one of the largest projects ever undertaken by the Water Corporation. Once commissioned in 2028, it will provide an initial 50 billion litres of climate-resilient drinking water annually to support Perth's growing northern communities.
To put that volume into perspective, it's enough water to supply more than 2.5 million people and fill Optus Stadium approximately 50 times. The project's construction is expected to create over 1,500 jobs and inject an estimated $1.1 billion into the Western Australian economy.
Nathan Hardwick, Water Corporation's acting general manager of assets, planning and delivery, said construction is powering ahead. "When commissioned in 2028, ASDP will provide an initial 50 billion litres of climate-resilient drinking water to support growing communities in Perth's north," Mr Hardwick stated. He also emphasised that the plant will be fully carbon neutral.
Securing Water in a Drying Climate
The drive for new desalination capacity is underscored by stark climate trends. Over the past half-century, rainfall in southern WA has declined by around 20 per cent, leading to an 80 per cent drop in streamflow into dams.
WA Water Minister Don Punch stressed the critical nature of the Alkimos project for the state's future but reminded residents that infrastructure alone isn't the complete solution. "While it's no secret that desalination is fundamental to water security in WA, it remains important that people do not get complacent when it comes to being waterwise," Minister Punch said.
"With large parts of southern WA experiencing some of the driest years on record, it's up to everyone to make sure we use water, our most precious natural resource, as responsibly as possible."
Early work on the site, located next to the existing Alkimos Wastewater Treatment Plant, began in late 2023, with major construction kicking off in mid-2024. Another crucial component, WA's largest-ever water pipeline, is currently being laid across Perth's northern suburbs. This 33.5km underground trunk main will link the desalination plant to the Wanneroo Reservoir and is slated for completion by 2027.
The successful installation of the high-voltage power cable is a pivotal logistical milestone, ensuring the future plant has the energy it needs to turn seawater into a secure drinking supply for generations of West Australians.
