The $200 million Belmont desalination plant has been granted planning approval as part of a plan to improve the Lower Hunter's water security.
The project, which will deliver up to 30 million litres of drinking water a day, will form part of the draft Lower Hunter Water Security Plan to be released next week.
"Desalination is one of only a few water supply options that is rainfall independent, helping us to continue to support our customers and communities regardless of changes in weather or climate," Hunter Water managing director Darren Cleary said.
"The Lower Hunter community gained a sense of what a prolonged and severe drought would be like when we all experienced the most recent drought through 2019-2020.
"Fortunately, the drought broke with good rainfall.
"The region's water system can fall from typical levels to 15 per cent in less than three years, even with the implementation of a range of drought response measures and restrictions. Had the drought continued beyond three years, our region could have run out of water."
The Belmont plant's drinking water production capacity was increased from 15 million to 30 million litres per day to provide greater drought security, reliability and operating efficiency.
By comparison the existing Sydney desalination plant is capable of producing 250 million litres per day.
The planning approval also confirms the direct ocean seawater intake system, which involves piping seawater from a kilometre offshore.
Water Minister Melinda Pavey said the project was part of a plan to drought-proof regional communities.
"The Lower Hunter's storages are relatively small and shallow, resulting in water levels dropping quickly. In a severe drought, water storages can drop from typical operating levels to 15 per cent in less than three years," she said.
Mr Cleary, said the planning approval provided the Lower Hunter with certainty should an additional source of water be needed during drought.
"Planning approval for the Belmont desalination plant gives us an additional tool to help close our supply gap during periods of drought and provide up to an additional 30 million litres of water each day, he said.
"The Belmont plant is now part of our region's ongoing water security package. Hunter Water is finalising the review of the Lower Hunter Water Security Plan, which will outline additional proposed supply and demand measures to ensure a resilient water supply for our region that caters for growth and can respond to the impacts of drought and climate variability."
