Area News letter to the editor: February 14, 2018.
The ultrasound cyanobacteria control unit floating on south Lake Wyangan mentioned by Griffith Mayor dal Broi on local radio recently are totally impractical in this place.
Also a waste of time at Barren Box Swamp where there are a number of ultrasound units.
Wetland plants will do it for nothing!
Murrumbidgee Irrigation (MI) are installing these units to make out they are doing something, and the Mayor dal Broi has repeatedly announced the employment of a Project Manager for Lake Wyangan.
He dismisses Victoria Lake Shepparton water treatment as it is not useful and says “it is only a puddle”. This comment shows he has no understanding of processes in wetlands.
The principle applies everywhere: just focus on the single method of building shallow treatment wetlands with appropriate hydraulic retention times.
I believe the Mayor should not be leading the Lake Wyangan Committee. Councillor Simpson who heads up the Wine Grape Marketing Board should be reinstated after he was unceremoniously dumped as the lake committee Chairman and the Mayor installed himself.
MI cannot or should not pump south Lake Wyangan water into the Lakeview Branch Canal as it is persistently at Red Alert or near Red Alert bacteria level.
The dominant cyanobacteria in Lake Wyangan (and Barren Box Swamp) at present is Microcystis: It has the following characteristics: Species of microcystis are a common cause of blooms.
They produce a polypeptide microsystin. Variably release persistent toxins into the water. Toxic to animals ingesting contaminated water.
Implicated in human illnesses such as necrosis of the liver (from ingestion) and severe dermatitis.
It is not the only cyanobacteria I have identified in Lake Wyangan.
A duty of care should be rigorously applied to use of this water.
MI says it keeps south Lake Wyangan water for irrigation yet loses 1.5 metres/annum from evaporation; which brings water users to the MI-managed 3000ha Barren Box Swamp, much lauded 10 years ago, now dominated by cyanobacteria and an ecological disaster.
MI will not talk about it or the Lake Wyangan water balance and water quality.
Geoff Sainty OAM, Griffith.