Environment and flooding experts have slammed comments made by western Sydney minister Stuart Ayres on Seven News last night.
Mr Ayres was interviewed by the program in relation to the flooding risk in the Hawkesbury-Nepean Valley should Warragamba Dam, which is currently at 96.3 per cent capacity, spill.
The NSW Government has proposed raising the dam wall in an effort to mitigate the risk of flooding in the Hawkesbury region despite concerns raised by indigenous residents, scientists, environmental action groups, local councils, politicians and the United Nations Educational, Scientific and Cultural Organization (UNESCO).
The last major flood event in the Hawkesbury-Nepean Valley took place in 1978 - the region has expanded considerably since then.
Mr Ayres told Seven News that the region was "experiencing weather conditions and a full dam for the first time in 30 years that increase risk to a level that we haven't seen before".
"The unfortunate thing is we may not be able to raise that dam wall before the rain arrives," he said on the program.
"I don't think water restrictions would have a material impact on reducing the amount of water, we're talking about a dam that went from 40 per cent to nearly full in a matter of three days."
Former SES Deputy Director-General, Dr Chas Keys said Mr Ayres should "listen to experts" instead of whipping up fear in the community about floods.
"Stuart Ayres needs to check the Bureau of Meteorology website before he implies that western Sydney is facing imminent flood danger," Dr Keys said.
"He is not educating people; he is spinning a preferred project.
"It is misleading and irresponsible for him to imply recent rain might lead to significant flooding on any of our major rivers, including the Hawkesbury-Nepean.
"People need to monitor the Bureau of Meteorology for warnings of developing floods, not listen to Stuart Ayres, who appears to be whipping up support for his flawed plan to raise the Warragamba Dam wall.
Dr Keys said the La Nina period which has already begun should not be taken as evidence of "certain impending flooding".
"What it means is a likely wetter-than-usual summer which will probably see flooding in some parts of the state," he said.
"It does not mean that flooding on the Hawkesbury-Nepean river system is guaranteed to happen.
"Raising Warragamba Dam is not the panacea for flooding that Stuart Ayres likes to imply.
"Warragamba Dam is not on the Nepean or the Grose Rivers, both of which can produce large floods without a drop of water flowing over Warragamba Dam wall.
"Therefore raising the dam wall cannot control flooding on these major tributaries of the Hawkesbury River."
Australian National University Professor Jamie Pittock said the NSW Government should limit further development on the floodplain if it was really concerned about flood risk.
"Raising Warragamba Dam won't reduce the flood risk from the tributary rivers downstream," Prof Pittock said.
"It won't stop more houses being built in harm's way on the floodplain. It won't raise low lying roads to enable residents to get to safety."
A NSW Government spokesman provided a statement to the Advertiser yesterday which said the Hawkesbury-Nepean Valley was the most flood-exposed region in NSW, if not Australia.
"More than 130,000 people currently live and work on the floodplain," the statement said.
"Research has shown the proposal to raise Warragamba Dam to temporarily hold back floodwaters is the most effective long-term option to reduce flood risk and protect lives, homes and livelihoods.
"The impacts of a temporary increase in upstream inundation - and options to manage, mitigate or offset those impacts - will be detailed in the EIS currently being prepared.
"The NSW Government looks forward to the public exhibition of the EIS, which will allow all interested stakeholders to provide comment when all information is equally available.
"The final decision on the dam raising proposal will only be made after all environmental, cultural, financial and planning assessments are complete."