Cottagers and vacationers on Lake Winnipeg say algae blooms on the lake are getting worse, after finding slicks of blue-green algae on beaches and boats over the Labour Day long weekend.

Although water quality specialists with the provincial government said the algae near the Grand Beach and Hecla-Grindstone areas did not have harmfully high toxin levels, cottagers called the "pea soup"-like slick on the lake's southeast shore gross.

Greg McCullough, a University of Manitoba researcher who studies the surface algae, said Tuesday a change in wind patterns is likely responsible for dumping the algae on the beaches.

"People are really noticing it right now because it's occurring more in the south basin than it has in the past and that's where a lot of people live," he said.

"But the people who fish in the north basin, the people who live up in the north basin, have been seeing this kind of thing for the last 10 years."

Hot, dry weather encourages algae growth

There is more algae growth this year because the weather has been hot and dry all summer, McCullough said. Such conditions have kept the water clearer, allowing more light to get through and encouraging more algae growth.

He said the problem appears to be getting progressively worse.

"It has been in the lake over the last few weeks, it has been building up," McCullough said.

"I've been watching satellite images over the summer, and all through August there's been a lot of algae in the south basin — probably as much [as] or more than I've seen in the last decade or so."

While not all algae contain toxins, McCullough warns against drinking water containing algae, in order to be safe.