Fish die, residents suffer in ‘black water’ event in Echuca, Swan Hill

A foul stench has enveloped a town in Victoria as a “blackwater” event is declared for the flood-ravaged area.

Residents in a small town in regional Victoria claim they’re enduring a potent, all-pervasive stench, with a “blackwater” event declared in yet another blow for the flood-ravaged town.

For those in Echuca and Mooroopna the smell has become almost unbearable, with one resident comparing it to “stepping into a sewer”.

“To use an old phrase, it’s a stench that would outlast religion,” Echuca resident Nick Dean told NCA NewsWire on Thursday morning.

The strong smell comes as conservation group OzFish claims “blackwater” – an event where there’s a sudden depletion in dissolved oxygen in the water – is killing thousands of native fish, leading to crustaceans to escape waterways in Swan Hill and Echuca.

Crayfish are crawling out of the ‘blackwater’ in Swan Hill, which is experiencing a spike in dissolved carbons as a result of recent flooding. Picture: Facebook

“You’ve got no idea,” Mr Dean told NCA NewsWire.

He said yabbies and crayfish were crawling out of the water, while at least 10 dead fish had floated past his home since Wednesday.

“The minute you open the door, it (the smell) nearly knocks you out,” Mr Dean said.

Crayfish in Swan Hill are surfacing to escape the blackwater. Picture: Facebook

The black water event is another blow to Mr Dean and his neighbours, whose homes are on the wrong side of a controversial flood levy dissecting part of the town.

He said the floodwater lapping his home had come from Shepparton and properties with overflowing septic systems and rotten crops.

Flooding began in Echuca earlier this month, but authorities are optimistic the worst has passed for the embattled town, with Emergency Management Commissioner Andrew Crisp saying the Murray River had peaked at 94.9m above sea level.

Charity OzFish sent workers and volunteers to Swan Hill on Thursday to rescue crustaceans, worker Braeden Lampard told NCA NewsWire. Picture: Facebook

Braeden Lampard, who works for fish conservation group OzFish, said volunteers and workers were moving into Swan Hill, a town north of Echuca, to rescue crustaceans trying to escape increasingly carbonised waterways.

Mr Lampard told NCA NewsWire fish and marine species were increasingly stressed, as broken down debris and vegetation washes into water ways, increasing the amount of dissolved carbon.

He said towns such as Swan Hill and Echuca were experiencing a “perfect storm” blackwater event.

Last week, Dr Janet Pritchard from the Murray-Darling Basin Authority said water was extending onto flood plains for the first time in many years, causing carbon-based debris to be swept into the waterways.

“As this material is consumed and broken down by bacteria, oxygen can be sucked out of the water, making it difficult for fish and other aquatic animals to survive,” Dr Pritchard said.

The Victorian Department of Environment, Land Water and Planning has been contacted for comment.