THE state government is seeking community comment on plans for a $100-million temporary water desalination plant in Lake Macquarie.
The Department of Planning, Industry and Environment is asking for community feedback on an application by Hunter Water for a 'drought response desalination plant' at Belmont.
The proposal is on public exhibition until Thursday, December 19.
The department's executive director of infrastructure assessments, David Gainsford, said community input was vital to the planning process.
He encouraged Lake Macquarie residents to have their say on the proposal.
"Hunter Water has lodged a State Significant Infrastructure application for a desalination plant at Belmont which could be used to supplement the Lower Hunter's water supplies during times of extreme drought," Mr Gainsford said.
The desalination plan would be able to make 15 million litres of fresh water each day from seawater.
"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."
Mr Gainsford said the proposed plant would be built next to the Belmont Wastewater Treatment Plant, off Ocean Park Road.
Hunter Water said the desalination plant would be built only if the region's total water storage level fell to 35 per cent of capacity.
The total water storage level for the region is this week at 59.6 per cent of capacity.
That's a 1 per cent fall on the level last week.
On its website, Hunter Water forecasts that even with a dry outlook, water storage levels would remain above 40 per cent of capacity in six months.
An average rainfall outlook would see water storage levels recover to 80 per cent of capacity in the same time frame.
Hunter Water said the desalination plant would be decommissioned once the storage levels recovered to 50 per cent of capacity.
"In the event that storages drop to this (35 per cent of capacity) level, modelling of an extreme drought prepared for the Lower Hunter Water Plan indicated that the facility may operate for periods of up to one year, and be on standby for up to two years prior to decommissioning," Hunter Water said.
"The seawater intakes, pipelines and power supply will remain as permanent infrastructure once constructed, however the desalination plant itself may be demobilised," the water authority said.
The desalination plant is one of a range of a drought-response measures set out in the Lower Hunter Water Plan.
These measures focus on both reducing water demand and increasing water supply.
Mr Gainsford said the proposal before the department was for an $87-million desalination plant.
"It includes construction of seawater intake wells, process units, and upgrades to power and water connections," he said.
"Hunter Water advises it has further plans for associated pipeline infrastructure that could bring its overall investment to about $100 million.
The reverse osmosis plant would pump in seawater which would be filtered to remove salt and impurities to provide fresh water for the Lower Hunter.
"Desalinated water would be tested to ensure it meets drinking water quality requirements. Remaining brine water would be pumped back into the ocean via the existing Belmont Wastewater Treatment Plant outfall," he said.
"We want to hear from the community about their views on this proposal to help us undertake a thorough and rigorous assessment and ensure any potential impacts to the surrounding area and local residents are considered," he said.
Among the potential environmental impacts flagged were minor soil and coastal erosion, a temporary reduction in air quality, as well as traffic, amenity and noise impacts during construction.
"The department will consider all community submissions along with advice and feedback from government agencies including Lake Macquarie City Council."
The State Significant Infrastructure (SSI) Application, Environmental Impact Statement and accompanying documents can be viewed on the Department's website at planningportal.nsw.gov.au/major-projects/project/10546
Residents can also view the application at Lake Macquarie City Council, Hunter Water's head office, and Belmont Library.