"Raising Warragamba Dam wall is an obscene waste of taxpayers' money which will fail to alleviate flood risk and do enormous cultural and environmental damage to the Blue Mountains.
"The NSW Government should be urgently prioritising construction of flood evacuation roads in western Sydney for existing floodplain residents."
The state government has proposed raising the dam wall in an effort to mitigate the risk of flooding in the Hawkesbury Valley region.
However indigenous residents, scientists, environmental action groups, local councils, politicians and the United Nations Educational, Scientific and Cultural Organization (UNESCO) have raised various concerns about the plan.
Western Sydney minister Stuart Ayres did not respond to Advertiser questions about the expected cost for the dam wall raising project.
Instead his office sent through the following statement from a NSW government spokesman.
"The final cost estimate for the proposal to raise Warragamba Dam for flood mitigation will not be known until the Environmental Impact Statement (EIS), final business case and detailed design are completed, any conditions of planning approval are known, and a competitively priced contractor is selected," the statement said.
"The NSW Government remains committed to the completion of the EIS and Final Business Case to fully assess the project on its merits.
"No final investment decision will be made until all environmental, cultural and financial assessments and planning approvals are complete."