Scientists are urging major dam projects in NSW and Queensland be abandoned, warning of significant environmental and agricultural consequences.
ANU Professor Jamie Pittock, a member of the Wentworth group of concerned scientists, told a conference on Wednesday the Wyangala dam proposal in NSW is expected to cost more than $2 billion dollars, with alternatives not properly explored.
"There are many alternatives to increase water security for all ... it can't be full to supply water and empty to catch a flood," Professor Pittock said.
He called on the NSW government to abandon Wyangala expansion plans as well as Dungowan Dam near Tamworth, and said Queensland's Hells Gates proposal should also be shelved. "The proposal to raise Wyangala Dam is an exemplar of why these dam-building projects are crazy," he said.
"It was proposed without a business case."
Prof Pittock, who has studied water policy for two decades, said the proposals are "unjustified and ill-conceived water management interventions", and has called on the federal government to abandon them.
The NSW government has said money for dams is contingent on a co-funding agreement with Canberra.
"If that money was spent on the alternatives, could the alternatives deliver the same or better benefits with less impact?" Professor Pittock asked on Wednesday. "There are better ways at reducing flood risk and better ways for securing water for agriculture."
Farmers, traditional owners, scientists and politicians have told a two-day Listening To The Lachlan conference about the impact NSW's dam proposals will have on the river. Internationally renowned expert on Australia's water resources Richard Kingsford also wants the projects abandoned.
The UNSW professor will tell the conference the proposals will lead to devastated wetlands.
Forbes mayor Phyllis Miller said the Wyangala dam needs to go ahead. "To those people that believe raising the wall and inundating some land up in the dam catchment is an environmental problem, let them come see what a flood does," she said.
NSW Water Minister Kevin Anderson said he looked forward to receiving a commitment from the federal government for "these crucial water infrastructure projects".
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