Pilot project uses nanobubble technology to battle algae blooms in Manitoba lake

CBC

16-06-2025

After years of trying everything from aerators to chemical treatments, a southwestern Manitobalake plagued by stubborn algae is testing a new solution — bubbles too small to see.
Betty Sawatzky, Killarney Lake Action Committee chair, said cyanobacteria, also known as blue-green algae, is a problem in Prairie lakes.
"It's a turquoise colour and it's toxic," she said. "You're at the mercy of the wind, at the heat, humidity, the nutrients that go into the lake."
To improve water quality and prevent harmful algae growth, a nanobubble unit is being installed in Lake Killarney. Sawatzky said the pilot project is the first of its kind in Manitoba and uses technology that infuses water with ultra-fine oxygen bubbles, which stay suspended longer than traditional aeration systems.
Sawatzky said that helps disrupt the conditions that fuel algae blooms. The project is part of a broader push to find eco-friendly, science-backed solutions that support the lake's ecosystem.
Past efforts to deal with problem
Lake Killarney has struggled with algae blooms for years, leading to beach closures and fish kills, Sawatzky said. An aeration system added in 2017 helped prevent closures and fish deaths, but algae still return.
Sawatzky said the nanobubble system uses the same concept as the current aeration system — just on a much smaller scale. It disperses bubbles throughout all levels of the lake to reduce the available phosphorus that feeds algae blooms.
"You've got those tiny micro bubbles at the bottom, in the middle and towards the top ... It can work to break down those extra nutrients that feed the cyanobacteria that feed the algal blooms," she said. "If you can stop the food source of these algal blooms ... You solve your problem."
After three years of research to find an eco-friendly and cost-friendly solution for the algae, the committee partnered with Calgary's SWAT Water Technology to test nanobubble technology in a six-month pilot project, said volunteer Shane Warnez.
The unit, which was placed in a small section of the lake known as The Bay Friday, is just a little bigger than a dehumidifier and has two hoses.
One draws water in and injects it with oxygen bubbles, and the other hose sends it back into the lake.
Warnez said the lake may look worse at first, with some foaming, but if it works, the water should clear.
"It'll be very obvious because there will be less algae and as a result, the lake will look a lot cleaner and clearer," he said. "It's really esthetics that we're looking at."
Water testing will track phosphorus and dissolved oxygen levels. The trial cost about $11,000, with SWAT Water Technology lending the machine at no cost. The main expenses are water testing and about $2,500 in electricity, which the local agricultural society is covering.
Community watching closely
Cheryl Burke, who co-manages the nearby Kerry Park Campground, said algae has hurt tourism over the years.
"At the beginning of the season, it's good. And then as soon as the heat hits it, it's green," Burke said. "I think we'd attract more people to the community if our lake wasn't green."
She remembers the 1990s when the water was clear and the beach was full. She said algae can get so bad these days that people hesitate to let their dogs swim in the lake.
The community is hopeful and is watching the pilot project closely, Burke said.
For now, the unit remains on the east side of the lake in The Bay, Sawatzky said. If things start to change for the better, he said it would hopefully trigger the go-ahead to install additional units across the lake.