A desalination plant could be built in the Illawarra under Sydney Water's new master plan for the region.
Subscribe now for unlimited access.
$0/
(min cost $0)
or signup to continue reading
The reason is to look to reduce the region's reliance on water from Avon and Cordeaux dams as the Illawarra's population rises.
"We are looking at a 30 per cent increase in population to 2056," said Kate Miles, Sydney Water's Head of Systems and Asset Planning.
"We've also got climate change which is a critical issue for the water industry with the impacts that that does have on our very rainfall-dependent water supplies.
"It seems funny to talk about the risk of drought when it seems like we've been in a period of flooding more frequently than drought recently.
"But we know that in Australia the climate is swings and roundabouts. The climate is becoming more extreme though some more extreme floods, but also more extreme droughts."
WaterNSW, which looks after the state's dams, had started looking at the Illawarra as a location for the state's second desalination plant in 2020, with a view to making the region more resilient in times of drought.
Later that year, it appeared a site at Port Kembla had been selected for the plant but since then the planning has been taken over by Sydney Water.
"The Illawarra desal [plant] is in the plan as something that we would implement in the future as growth continues to occur," Ms Miles said.
"We're looking to get it developed all the way up to being effectively something that we can then sit there that's ready to produce so if we do come into another extreme drought, it's something that we can pick up and implement in time."
She wasn't able to identify a specific location as there were still several sites in play.
The Sydney Water master plan looked at four options to service the city tagged Traditional, Resource Efficient, Water Resilient and Eco-sensitive - only the last two included the construction of a desalination plant.
Of those, Sydney Water has chosen the Water Resilient option which offered, "significant reduced reliance on bulk water supply and improved rainfall-independent supply from desalination to service the Illawarra region".
It stated 39 per cent of the region's water needs would be supplied by the desalination plant, with 28 per cent coming from Avon.
The model also includes 25 per cent reused wastewater and 8 per cent reused stormwater.
Ms Miles said recycled water systems were already in use, for toilet flushing, irrigation and industry uses.
But using what they called "purified recycled water" for drinking was already being done elsewhere.
"There's, I think, 35 cities around the world that already implement that kind of technology including in Australia," she said.
"In Perth, they put it into aquifers and then and then pump it back out again.
"So that is an option and we're also looking at. Probably the higher likelihood option is recycling stormwater as well in the Illawarra."