Annastacia Palaszczuk defends new multibillion-dollar Queensland desal plant

Annastacia Palaszczuk’s cabinet rejected the cheaper option of permanently adding recycled water to the region’s drinking supply and greenlit a new desalination plant.

Queensland Premier Annastacia Palaszczuk on Tuesday. Picture: NCA NewsWire /Tertius Pickard

Annastacia Palaszczuk has ­defended the decision to build a new multibillion-dollar desalination plant to top up southeast Queensland’s drinking supply instead of turning on an existing recycled water scheme.

Government agency Seq­water warned the government a new drinking water source would be needed in the next decade because of surging population growth and impacts of climate change.

The Australian revealed on Monday state cabinet rejected the cheaper option of permanently adding recycled water to the region’s drinking supply. Instead it greenlit a new desalination plant north of Brisbane, expected cost between $4bn and $8bn to construct.

Peter Beattie’s Labor government built the $2.5bn Western Corridor Recycled Water Scheme during the last drought, but it has never been used for drinking. It would take two years to recommission, but would be largely cost-neutral.

Ms Palaszczuk said the scheme would only be used for drinking as an “insurance policy” in extreme droughts but would continue to provide water for industry. “We need it all,” she said. “We’ve got new industries coming on board, we’ve got the agricultural industry … the hydrogen industry, all of these industries will also need water as well.”

Under the region’s 30-year strategy, recycled­ water – wastewater or sewage disinfected and treated to become purified drinking water – would be added to drinking supplies if dam levels dropped to 40 per cent. On ­Tuesday the water grid was at 69 per cent.

Stuart Khan, a UNSW professor in the school of civil and environmental engineering, said using the recycled scheme for drinking water made more sense than desalination because taxpayers had already funded the infrastructure.

“To go and spend, potentially, another $8bn on top of that without making use of that initial investment, I would say is fiscally irresponsible,” he said.

“Some of that cost will come back to taxpayers through increased water bills but there will also be ongoing additional costs.

“The operational costs for seawater desalination are much greater than the operational costs for purified recycled water, and that mainly comes down to the electricity bill.”

Professor Hubert Chanson, a hydraulic engineering expert at the University of Queensland, said there had been “unfortunate community opposition” to recycled water. “In my opinion, in the long term, including the operational costs, desalination will be more expensive,” he said.