Farmers in the state's south say water authorities are failing to prepare for severe flood risks in the Murray Valley as La Nina conditions threaten to fill major dams and rivers.
NSW Farmers Conservation and Resource Management Committee chair Louise Burge said while authorities may not be able to prevent all risks of flooding this year, they should "absolutely" avoid making flooding conditions even more extreme.
"The decision to keep Hume Dam at 96 or 97 per cent full means there is limited capacity to absorb any risks of large rain event in mountain catchments," Mrs Burge said.
"Rules around the management of Hume Dam do allow a level of airspace to absorb another large rainfall event, but authorities are not enacting these rules even though there are no risks to irrigation interests if the rule was used to help mitigate flood risks.
"The risk of catastrophic flooding is even worse than what we saw in 2016 when the Central Murray Floodplain Plan failed and farmers had their livelihoods washed away by dam releases."
Southern Basin storages were already near capacity, Mrs Burge said, but a reliance on Millennium Drought modelling had led to the decision to keep Hume Dam almost full. This was despite the combined risk of Dartmouth Dam sitting at full capacity, Victoria's Lake Eildon Water also at 96 per cent full, and other Victorian tributaries continuing to fill the Murray River.
"We look set to repeat the flood devastation of 2016 unless government officials and politicians acknowledge the risks and importantly try to prevent as much damage as possible," Mrs Burge said.
"In 2016, local farmers warned of the high risk of flood in a La Nina year but were ignored and as a result Hume Dam management led to catastrophic flooding in the Murray Valley because authorities didn't use existing airspace rules that could have helped reduce the severity of flooding.
"I am really worried that we will see this repeated in 2022, but authorities are still not understanding that the risks are far worse this year than in 2016. It is a pressure cooker at present and the risks of a flood disaster are real."
Water management was a hot topic in the Southern Riverina with rising water levels prompting farmers and businesses to sound the alarm on the flood risk.
"Our families have lived here for four generations, we know how flood risks occur, but calls by farmers closer to Albury and further downstream for authorities to implement existing airspace rules are being ignored," Mrs Burge said.
"Dartmouth (Dam) is effectively full, Victorian tributaries are running high, and if Victoria's Goulburn River also goes into flood, flood impacts will be even higher than 2016 as Murray River Flows are forced north through Deniliquin and the Edward Wakool river system.
"I drove through the Millewa Forest recently and the forest is full, water is lapping the main Tocumwal to Mathoura road in several spots. With full rivers, creeks and forests in the upper- and mid-Murray, there is a flood disaster waiting to happen."
