GRAND BEACH, MANITOBA – On the last glorious Sunday in August, lifeguard Maddi Danyluck walked down the most famous beach in Manitoba as the sun set fire to a bank of clouds right where the blue lake merged with the western sky.
Danyluk had one eye on the kids still romping in the water, but the other was on the turquoise stains that streaked the golden sand.
"There's tons of it," she said, wrinkling her nose at the blue-green algae lining the beach and floating like a dense mat of grass clippings in the shallows. "It just stinks."
It also threatens to kill Lake Winnipeg, proudly known as the sixth Great Lake among the Canadians who flock to its famous beaches and fish its waters for walleye. In just two decades, pollution in the lake has doubled, with most of it coming from the Red River that runs north through the rich agricultural lands of Minnesota, the Dakotas and Manitoba.
The decay in Lake Winnipeg is a stark example of what Minnesota faces as its rivers are increasingly degraded by a transformation of the land around them: The price flows inevitably downstream, and it's excruciatingly difficult to fix once pollution takes its toll on a river.
Visitors to Lake Winnipeg find that their treasured short summers are marked by increasing numbers of sometimes toxic algae blooms, which chase swimmers away from the beaches and foul the nets of fishing families that have made their living here for generations. Temporary dead zones — water devoid of aquatic life — are starting to appear in the lake's vast northern basin, a sign that the lake may soon reach a tipping point.
While the Red River provides only 15 percent of the water in Lake Winnipeg, it carries almost 50 percent of the phosphorus that is creating the algae, mostly from the vast farmlands in Minnesota and North Dakota.
Now, after years of research and gentle pressure from Canadian governments, the United States and Minnesota have signed on to a simple plan called the Lake Friendly Accord: Cut phosphorus pollution from farms, cities and water treatment plants by 50 percent.