The decision by the Goulburn Broken Catchment Management Authority to inject a further “environmental flow” into the Goulburn River next week – after sustained high rivers since May – beggars belief.
Recreational users and fishers have attacked the flow as entirely unnecessary after winter and spring heavy flooding events — yet next week’s late spring fresh will be the second “environmental flow” deployed by the CMA in just 10 weeks, despite unusually high natural flows.
After some agitation from fishers and users, the CMA delayed the early September fresh by just a week, to allow for the start of the trout fishing season (when other government agencies deliver large quantities of stocked fish to the river to promote fishing activity during the school holidays).
Then the October 4 deluge occurred, when the river rose rapidly and flowed over its banks, sparking fears of another major flood event. This wasn’t the CMA’s fault, of course, but a fortnight after the river has subsided, it plans another environmental flow before the riverbanks have dried out, further delaying the re-establishment of streamside vegetation.
No academic issue
This is no academic issue: many new treefalls from the soft lower banks have been reported, and the massive bank slump behind Aquamoves shows what happens when the Goulburn’s clay banks are softened, trees fall in, and further bank collapses and erosion occurs. This silts the bottom of the river, making it shallower, then hastening the speed of the river flow — causing further bank erosion.
The justification for next week’s environmental flow is thin at best: The CMA described it as a “perch spawning fresh” designed to stimulate the breeding of golden and silver perch. Fishing groups point to the recent report card from the Arthur Rylah Institute, showing record numbers of perch, trout cod and Murray cod in the river.
Fishers would rather have access to the river, as would campers and people wanting a swim, or picnic on a sandbar.
The CMA’s dogged pursuit of environmental flows regardless of natural flows in fact follows to the letter a seasonal watering plan released by the Environmental Water Holder in June. That plan lists the expected watering effects as perch spawning, scouring the river bed to preserve pools and improving water bug habitat by “scouring fine sediments and biofilms from hard substrates.”
The latter two effects have, of course, been amply taken care of by the massive flows between June and the end of October. So, what’s up? Fishing groups said last week they heard from other government sources that the late spring fresh was “locked in,” suggesting that the consultations the CMA held with user groups were mere window dressing.
What is the real reason?
This quickly diminishes trust and encourages speculation: is this about reducing the Eildon storage, currently near capacity? Or is the Environmental Water Holder calling the shots?
To our mind, the CMA needs to be seen to be properly managing our catchment, of which our rivers are the lifeblood. And it needs to be taking the community with it.
The environmental objectives for the Goulburn include “maintaining the form of the riverbank and channel and a high diversity of bed surfaces to support all stream life;” and “increasing the abundance of aquatic and flood-tolerant plants in the river channel and on the lower banks to provide shelter and food for animals and stabilise the riverbank.” As well as increasing populations of fish, platypus and turtles.
Pushing large amounts of water down the river when it is likely to cause further damage and delay streamside re-vegetation hardly meets these objectives. If the CMA is not looking after our river, who is?