Goulburn Broken Catchment Management Authority (CMA) is monitoring dissolved oxygen levels in sections of the lower Broken Creek.
Goulburn Broken CMA Environmental Water Manager Simon Casanelia said monitoring data showed dissolved oxygen levels had been dropping over the past two weeks at Rice’s Weir on the Broken Creek near Barmah and were approaching critically low levels.
“The flood water affecting the lower Broken Creek is laden with organic material such as eucalypt leaves, grass and twigs,” Mr Casanelia said.
“When this organic material breaks down it draws oxygen from the water. Low dissolved oxygen levels can cause stress to fish, crayfish and other animals that breathe underwater. If dissolved oxygen levels are low for extended periods it can also result in their death. Generally native fish and other aquatic animals are pretty resilient and seek out more favourablewater quality.”
The flows along the creek are natural flows and a result of run-off and inflows after recent heavy rain.
“The current high water levels along the lower Broken Creek and the Murray River near Barmah mean that unfortunately environmental water can’t be delivered to increase dissolved oxygen levels,” Mr Casanelia said.
“Until this is possible, we will continue to work with the relevant agencies to monitor water quality conditions and attempt to address any problems if they occur.”
No native fish deaths have been reported to date. However, the community is encouraged to report fish deaths to the EPA on 1300 372 842.
For more information on dissolved oxygen levels visit: http://www.mdba.gov.au/managing-water/water-quality/blackwater
For more information on river flows and flood warnings visit:
http://livedata.mdba.gov.au/system-view
http://www.bom.gov.au/nsw/flood/rain_river.shtml