If approved, the plant is designed to supplement water supplies in the lower Hunter during extreme drought.

Department of Planning, Industry and Environment infrastructure assessments executive director David Gainsford said the draft proposal required public feedback as a crucial part of its assessment process.

"The desalination plant, which is considered State Significant Infrastructure, would be able to make 15 million litres of fresh water each day from seawater," Mr Gainsford said.

"This would cater for over 10 per cent of the Lower Hunter's water needs during periods when Level 3 water restrictions are in place."

If approved, the $87 million plant will be built near the wastewater treatment plant off Ocean Park Road.

The proposal is exhibited until December 19 through Lake Macquarie City Council, Hunter Water's head office, Belmont library and planningportal.nsw.gov.au.

The Newcastle Herald reported earlier this year that the plant was designed to be turned on when water storages hit 35 per cent.

An examination of environmental impacts flagged minor soil and coastal erosion and temporary air quality, traffic, amenity and noise impacts during construction.

It also notes the Hunter's water levels can "drop very quickly", from 65 per cent to 35 per cent in roughly 14 months and from 35 per cent to 15 per cent in about 10 months.

"Ultimately, the project would provide a rainfall-independent water source in the event of an extreme drought and slow the depletion of existing water storages by providing up to 15 megalitres a day of potable water," the documents state.

"The desalination plant would be run until an appropriate trigger point is reached in total water storage level, currently set at around 35 per cent."

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