Bird

Duck Weed Build-up on Broken Creek

Friday 26 August, 2005
Significant sightings of duckweed (floating azolla) have occurred on the Lower Broken Creek in recent weeks.

Significant sightings of duckweed (floating azolla) have occurred on the Lower Broken Creek in recent weeks.

The Goulburn Broken Catchment Management Authority (GBCMA), together with Goulburn Murray Water and the Environment Protection Authority are working to reduce potential impacts.

Mr Bill O’Kane, Chief Executive Officer of the GBCMA said high flows from the River Murray are being passed through the Lower Broken Creek system, which will assist in flushing azolla and freshening up the water generally.

“This will reduce the potential for the weed to impact on water quality, in particular the amount of dissolved oxygen present in the water,’’ Mr O’Kane said.

The GBCMA is also investigating the potential to transfer water from the Goulburn River via the Lower Broken Creek on its way to the River Murray.

In previous years, build up of the weed associated with low flows from the upper catchment of the Broken and Boosey creeks has resulted in low dissolved oxygen levels with the potential for fish kills along the lower reaches of the creek. A fish kill occurred in 2002. Close monitoring has been implemented to avert similar events.

Surveillance of the system is being undertaken by field staff from partner agencies. Continuous water quality monitoring is occurring at Rices Weir.

Mr O’Kane said close monitoring of dissolved oxygen is critical.

“Current oxygen levels are at an acceptable level, ranging from 8.6 mg/l to 12 mg/l, but a rise in water temperatures from sunny days increases the chances of low dissolved oxygen levels and the risk of fish kills.”

“The Broken Creek is enormously valuable to our community and we are working to protect the stream’’ Mr O’Kane said.

Release ends

For more information contact Bill O’Kane on 28 222288 or Lisa McKenzie 0427 212 651.