The Barnett Government has announced a major increase in the State’s use of desalinated water, revealing a $450 million expansion of the desalination plant at Binningup south of Perth.
Water Minister Bill Marmion revealed the average household water bill would need to increase by about $1 a week to meet the cost of the 50 gigalitre expansion.
The Southern Seawater Desalination Plant has just started supplying drinking water, with stage one of the project expected to be fully commissioned by the end of the year at a cost of $955 million, but the Government has already decided an expansion is the best way to tackle Perth’s worryingly low supply levels.
The move was announced this afternoon by Premier Colin Barnett and Water Minister Bill Marmion.
The stage two expansion is expected to be completed by December 2012 and will add 50 gigalitres to the facility’s supply capacity of 100 gigalitres.
Of the $450 million cost of the project, $300 million is to be funded from the “reprioritisation” of funds from existing projects. The remaining $150 million will be borrowings, adding further pressure to the State’s burgeoning debt.
Mr Barnett said the decision was taken because Perth could not take rainfall for granted.
“The expansion of the Southern Seawater Desalination Plant was necessary because we can no longer rely on rainfall run-off into our dams as a major source of drinking water,” he said.
“Despite the welcome, recent rain, long-term forecasts show the south-west corner of Western Australia will become even drier in the future.
“It’s important we act now to ensure security for the Integrated Water Supply Scheme that supplies drinking water to Perth, Mandurah, the Goldfields and towns along the way to Kalgoorlie-Boulder.”
The Government had been looking at various options to secure Perth’s drinking water supply into the future, including recycling waste water, increasing the amount drawn from the Gnangara Mound and tapping the northern section of the Yarragadee Aquifer.
Mr Marmion refused to say which projects would need to be cut or deferred by the Water Corporation to find the $300 million of savings to fund the expansion.
But he said the Government would continue to explore its options for future supplies, including recycling through groundwater replenishment. A contentious recycling and replenishment trial, which sees treated wastewater being re-injected into the Gnangara mound, will not be affected by the cuts.
“At the same time, the Government believes that everyone must continue to play a role in becoming even more water efficient,” he said.
Mr Marmion said by the time stage two was completed, half of Perth’s annual supply would come from “climate-independent sources”.
