Goulburn Broken Catchment Management Authority environmental water and wetlands manager Simon Casanelia said after recent assessments of bank vegetation, it was decided the planned delivery of water for the environment wasn’t necessary.
“Recent monitoring (along the Goulburn) showed that soil moisture is still good so there was no need for a water delivery,” Mr Casanelia said.
He said some vegetation growth on the banks had been delayed due to the floods so not delivering a flow would also give those plants a chance to establish.
The March-April environmental flow, which last year peaked around 6000 Ml/day, is usually timed to encourage native fish, such as golden and silver perch, to move from other river systems to the Goulburn River.
But concerns about an explosion in carp numbers in parts of the Murray and Broken rivers was another reason to not go ahead with the delivery.
Natural flooding is a boon for carp as it gives them access to floodplains, where large females can spawn millions of eggs and young have high survival rates.
Country News understands that many tonnes of carp have been caught up and observed at fishways, fish ladders and weirs along the Murray and Broken rivers.
Native fish numbers do not appear to have responded to the flooding in the same way as carp, but Mr Casanelia said they hoped to carry out fish monitoring along the Goulburn River in late March and early April to get a better understanding of the situation.
Inter-valley trade water delivery
Meanwhile, the Murray-Darling Basin Authority has called on inter-valley trade water to be delivered via the Goulburn River to meet downstream demands in the Murray system.
Goulburn-Murray Water water delivery services general manager Warren Blyth said the flows from Goulburn Weir would start increasing on Friday, March 17 to deliver water from the inter-valley trade account.
“The order is for about 30 gigalitres to be delivered over 14 days,” he said.
“Releases will gradually increase, peaking at 3000 megalitres a day before steadily declining.
“The planned flows are in line with recently introduced operating rules, which are designed to protect the health of the lower Goulburn River from sustained high flows over summer and autumn.”