Desalination plant fired up to dilute foul-tasting tap water

Desalinated seawater is being produced to dilute foul-tasting tap water as dams fill up across south-east Queensland.

Seqwater confirmed Thursday its Gold Coast desalination plant was operating at 70 per cent capacity, pumping about 100 megalitres a day into the regional water grid.

It follows complaints about the taste and smell of tap water across Brisbane and neighbouring council areas.

The Gold Coast Desalination Plant in Bilinga.

It is caused by an organic compound from algae known as 2-Methylisoborneol (MIB), and not considered harmful.

“It’s still very safe to drink, but there are some impacts from odour and taste,” a representative from Seqwater told Brisbane Times on Thursday.

Production from the impacted Mt Crosby Water Treatment plant – which filters the bulk of Brisbane’s drinking water – has been reduced.

Water from the facility is being diluted with additional water from the Gold Coast Desalination Plant and water from other treatment plants including North Pine.

The move was welcomed by Logan Mayor Jon Raven, who had raised residents’ concerns.

“This will mean you should notice a change in flavour and odour soon – however it may get worse as it gets better in some parts of the network as the earthy tasting water is pushed through the network,” Raven said in a social media post.

The desalination plant has historically been used for drought mitigation, but is now being used as dams across the region fill up.

Releases from Wivenhoe and Somerset dams were planned from about 3pm on Thursday to maintain their capacity for flood mitigation.

Downstream bridges may be impacted.

Now-premier David Crisafulli ruled out construction of new desalination plants on the campaign trail last year, and said the state needed more dams.

“We’re putting a flag in the ground today and saying that we should get back to an era when we were proud to build dams in this state, and we are,” he said at the time.

“I do not believe that the option of desalination or recycled water is anywhere as efficient, as acceptable, or as visionary as building dams.”

Seqwater is the government bulk water supply authority.

Recent heavy rain caused flooding in the South Burnett, but is expected to be more severe in north Queensland in the coming days.

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