WaterNSW has rescued trapped native fish and culled carp.

WaterNSW staff successfully rescued thousands of native fish trapped at Burrendong Dam and released them into the Macquarie River after months of preparation in a joint operation with fisheries experts from the Department of Primary Industries (DPI).

As part of the operation about two tonnes of pest species carp were culled from the river to be processed into fertiliser.

Over several days, more than 1000 golden perch plus hundreds of silver perch, catfish and Murray cod were netted and released downstream of the dam spillway into the Macquarie River.

The fish had all been trapped downstream of the dam’s spillway in a dissipater pond when the dam spilled during the food event of 2016, briefly connecting the pond to the Macquarie River nearby.

It is believed the fish either came over the spillway into the pond or made their way upstream via the river before being stranded in their thousands once the water receded.

In consultation with DPI experts, WaterNSW kept the pond oxygenated and monitored the well-being of the fish until the rescue began in early December.

Transferring the fish the short distance back to the river began with pumping water out of the pond so that commercial operators could net and sort the fish into native species and carp.

The natives were then ferried to the nearby river on vehicles fitted with specialist holding tanks and released in late December.

The release timing was dependent on achieving a degree of parity between the water in the pond and the river temperature.

WaterNSW executive manager assets, Ronan Magaharan said the operation involved WaterNSW dam operations and maintenance personnel from across the region.

“It’s a terrific environmental outcome that brought together teams from our dams at Wyangala, Windamere, Carcoar, Warren and of course Burrendong,” he said.

“As well as managing these major dams on behalf of the community, WaterNSW also plays an important role as an environmental custodian in these circumstances.

“It is a credit to all those involved that the complex and delicate operation to salvage these numerous native fish over many months was so successful.”