$350m desalination plan proceeds

THE Water Corporation is seeking environmental approval to expand the size of its proposed desalination plant at Kwinana.

Acting chief executive Garry Meinck said the desalination plant was one of the major options if the Water Corp needed to develop new water supplies.

It is proposing to upgrade the capacity from 30 gigalitres per year to 45 GL per year to improve the economies of scale.

The expansion has lifted the estimated capital cost to $346 million.

Two consortia, comprising French companies Veolia Water and Ondeo Degrenot and local partners Leighton and Multiplex respectively, have already pre-qualified to tender for the project.

Mr Meinck said the Water Corp had no immediate plans to proceed with the desalination plant.

“Our infrastructure is very well developed,” he said.

“We felt it was very important that we have a robust alternative available.

“We are developing this to the point it could be triggered if needed.”

Mr Meinck said the Water Corp’s preferred option was to draw water from the south west Yarragadee groundwater aquifer, which would be more cost effective than a desalination plant.

However, he acknowledged that the Yarragadee option was subject to environmental assessment and had generated some community disquiet.

The expansion of the desalination plant had reduced estimated costs to $1.11 per kilolitre, down from the previous estimate of $1.25 per kilolitre.

But the reduced cost is still substantially higher than the 85 cents per kilolitre cost of drawing water from the Yarragadee aquifer.

Mr Meinck said the Water Corp has held “advanced discussions” with Western Power about co-locating the desalination plant with the recently completed Cockburn 1 gas-fired power station.

It could potentially combine intake seawater with cooling water discharged from the power station.

The major environmental issue is the 50 per cent increase in the volume of concentrated seawater that would be discharged into Cockburn Sound.