Equipment is being deployed to Quamichan Lake as aeration trials begin to determine solutions for ongoing cyanobacteria blooms.
Last year, the Municipality of North Cowichan received provincial approval to test methods to improve oxygenation and reduce nutrients that contribute to cyanobacteria. Mayor Rob Douglas said the work marks a first step toward addressing long-standing concerns about the lake.
“Residents, lake users and Cowichan Tribes have raised concerns about Quamichan Lake water quality for many years and have consistently called for action,” Douglas said. “This trial responds to those requests, reflects strong support from the community and regulatory partners, and applies proven approaches to improve oxygen levels and reduce phosphorus.”
Three eight-metre-diameter cylindrical enclosures will be anchored to the lakebed. Two will use different combinations of aerators and metal additives, while the third will serve as a control to measure changes in water quality.
The municipality said testing will take place in two phases, first measuring the effectiveness of aeration, followed by testing nutrient binders.
Results will be shared with the province, council and the community before decisions are made on treatment options. The municipality said the findings could be applied elsewhere.
“Successful treatment options could also be applied to other parts of the watershed including Somenos Lake and marsh, which also experience regular algae blooms,” it said.
The trial is expected to run from May to August.
The $200,000 project is funded through the Cowichan Valley Regional District’s Drinking Water and Watershed Protection Program.
