The Berejiklian government says forecast climate change risks had forced it to amend its plan to raise Warragamba Dam, lifting the project's height by an additional three metres.
WaterNSW said in a letter to the federal Department of Agriculture, Water and the Environment, it needed to amend its application for approval based on information from the Bureau of Meteorology, CSIRO and a state-funded climate project with the University of NSW.
Hinted at in previous leaked information, the NSW government has formally sought to adjust the plan to raise Warragamba Dam 17 metres, not just 14 metres.Credit:Brendan Esposito
"Under modelling of a medium climate change projection in increases in rainfall intensity, the existing flood risk is set to increase," the letter said. "The existing dam crest would need to be raised 17 metres to achieve the same benefits in 2090 as raising the dam crest by 14 meters under historical conditions."
While the letter by project director David Harper says the variation "does not impact on Matters of National Environmental Significance that were not already included in the original proposal", elsewhere he states the approach "enables" the spillway crest heights to be raised in the future.