Goulburn Broken CMA is keeping an eye on water quality in creeks, rivers and wetlands across the catchment with forecasts for a dry, warm spring and summer.
“The Bureau of Meteorology has forecast another dry spring, which means below average stream flows and a strong chance that flows in many of the smaller creeks and some Goulburn and Broken River tributaries will be very low or may even stop during the next few months,” Goulburn Broken CMA CEO Chris Norman said.
The main risk to native fish is when oxygen levels in the water drop and fish become stranded in small, unconnected pools.
“Native fish and other aquatic wildlife generally try and move to shaded areas and deeper water during warmer weather, which is why the work we’ve done with the community to re-snag and revegetate waterways is so important,” Goulburn Broken CMA Environmental Water Manager Simon Casanelia said.
“Improving and protecting the bank vegetation that provides this valuable shelter was the main reason water for the environment was delivered along the lower Goulburn River in early spring. Reedy Swamp near Shepparton and Horseshoe Lagoon near Trawool have also received water for the environment this year and they will provide some of the few refuges in our region for waterbirds and other wildlife if conditions do remain hot and dry.”
Mr Casanelia said similarly dry conditions were experienced this time last year and sections of a number of creeks, including Seven, Hughes and King Parrot, dried out.
“Unfortunately we may see this happen again,” he said. “We are also keeping a close eye on the Broken River and the upper Broken Creek as there has been little or no inflows or run-off into these waterways in recent months.”
A small amount of water for the environment (about 15ML/day) is being released from Lake Nillahcootie to maintain a base flow in the Broken River downstream of the dam.
Options to protect threatened native fish species if waterways dry out, stop flowing or become stagnant include moving fish further downstream or aeration.
There is also an increased chance of blackwater if there are heavy summer storms.
“This is most likely to occur if there is heavy rain and flash flooding in the Strathbogie area and surrounding floodplains, which can wash leaf litter and other debris into the creeks, that then flow into the Goulburn River,” Mr Casanelia said.
The last time there was a blackwater event in the Goulburn River was in January 2017. Fortunately, extra water was available and was released from Goulburn Weir to help improve water quality. Environmental flows since then have also helped native fish populations bounce back.
Information about activities Goulburn Broken CMA supports to improve waterway health can be found at www.gbcma.vic.gov.au or phone 5822 7700. Information on river and stream flows can be accessed via the Bureau of Meteorology’s website www.bom.gov.au
Any fish deaths should be reported to the EPA on 1300 372 842.