Weed toxin ‘ standard’
SUNWATER has defended the use of strong chemicals to kill weeds in the Haughton pipeline water system after images emerged of piles of dead fish on the banks of a storage dam.
Photos supplied to the Bulletin showed dozens of dead fish washing up on the banks of the Haughton Balancing Storage last week, between the Burdekin Falls and Ross River dams.
A pumping station and pipeline from the storage were constructed in 1988 to connect to the headwaters of the Ross River Dam near Townsville.
A concerned member of the public, who took the photographs and wished to remain anonymous, claimed the use of the chemical affected fish, drove away native bird life and killed plants like lotus flowers.
A SunWater spokesman said the controlled treatment of Haughton irrigation channels using an acrolein herbicide was completed last week and was standard protocol.
The chemical is approved for use by the Australian Pesti- cides and Veterinary Medicines Authority.
“It is commonly used to treat aquatic weeds and algae in closed, man- made irrigation channels to maintain flow capabilities of distribution systems,” the spokesman said.
“Rapid and complete breakdown properties ( ensure) it does not adversely affect the natural environment.”
The SunWater spokesman said the company understood the chemical could be deadly to fish, however the fish in the irrigation channels were often pest species.
He said customers were notified of the water treatments in advance.
“Warning signs are erected at channel entrances and offtakes are isolated and locked while the process is completed,” he said. “Non- irrigation users are not able to take water for 72 hours after acrolein treatments have ceased as a further precaution.”
The SunWater spokesman said the Haughton Balancing Storage was only used for irrigation purposes and was not a stocked fish habitat or publicly accessible water course.
The Department of Environment and Science referred the Bulletin back to SunWater when questioned on the issue.