Indigenous groups are celebrating “a bit of a win” after the New South Wales government cancelled plans to raise the wall of Sydney’s main dam, a move that would have inundated more than 300 cultural heritage sites.
The proposal to raise Warragamba dam by 14 metres to reduce flood risks in the Hawkesbury-Nepean valley was formally extinguished this week with the government withdrawing its listing as critical state infrastructure.
“WaterNSW have now been directed to withdraw any planning applications made to the NSW government for the Warragamba dam raising proposal,” WaterNSW said a letter to the state’s planning department.
“It’s awesome. The best news I’ve had in eight years,” Kazan Brown, a Gundungurra elder, told Guardian Australia. “It’s a big weight off our shoulders.”
Traditional owners, environmental groups and even the Insurance Council of Australia opposed the project, which was put forward in 2016 by the Coalition government led by Mike Baird.
Initially touted as costing $700m, the likely bill had almost tripled to about $2bn by March this year, according to the Parliamentary Budget Office. That sum excluded the offset costs for the environment damage of flooding as much as 6,000 hectares of the Greater Blue Mountains world heritage area that the government put at $1.34bn as a minimum.
Coalition governments under three premiers had backed it as “the most effective infrastructure option to reduce the regional flood risk” for the 140,000 people living on the flood plain.
No funding, though, was ever allocated to the wall-raising and no business case was ever made, the current government said. Had the project been approved, planning and construction would have take seven to eight years.
The water minister, Rose Jackson, said the cancelling of the planning application was “the final step” of meeting Labor’s pre-election commitment to stop the plan.
“It’s a box-ticking exercise but it is a box that needed to be ticked,” she said. “WaterNSW needed to formally say ‘we are not proceeding with that project’.”
Jackson said the government was examining other options. One is to double the size of Sydney’s desalination plant to meet 30% of the city’s water needs, potentially lowering the reservoir’s maximum water level to give it so-called airspace to absorb more inflows before the dam spills downstream.
“We can’t do that whilst we’re so reliant on it for drinking water,” she said, noting the dam supplies about 85% of the city’s water.
The government had also made it clear “we do not want more development on the flood plain”, Jackson said. So-called in-fill development by raising the density of housing along transport corridors was instead the priority.
Harry Burkitt, one of the leaders of the Give a Dam campaign that had opposed the wall-raising, said it required unstinting efforts of “obsessive individuals” willing to endure a “slow, tedious, and paralysing” effort.
“There have been a handful of such people,” Burkitt said. “Their determination and devotion has today paid off.”
Rob Pallin, who helped fund the campaign through the Paddy Pallin Foundation he set up in his father’s name, called the project’s cancellation “a great win for the environment”.
Had the wall-raising gone ahead, it would have worsened the plight of threatened species inside a national park, including the Camden white gum and the regent honeyeater.
“It was more than just the issue of that campaign,” Pallin said. “It was more about setting a major precedent for allowing those sorts of things to happen in the future.”
Brown’s own grandfather had been forced off his farm 70 years ago to make way for the existing dam.
She plans to seek to have Lake Burragorang behind the wall included in the world heritage area to ensure more formal protection for the 334 known cultural heritage sites within the likely flood zone.
“I don’t think [the threat of a wall-raising] has gone away,” she said. Expanding the world heritage area “won’t stop the government … but it’s going to make it harder for them to put the wall up”.
Separately, Jackson said WaterNSW and Dam Safety NSW were continuing their work to examine the integrity of Warragamba dam in case of extreme flooding as the climate heats up.
Dam Safety had provided Jackson with an “assurance update” that the current investigations were “satisfactory” in their procedures.
“We’ll probably have something more final next year,” she said, adding the researchers would be granted whatever time needed to complete their assessment.
