Erie's problems

There are also plumes of harmful algal blooms spreading across the southern shore of Lake Erie in Ohio during the warm summer months - caused by phosphorus dumped into the lake by industries, municipalities, tributaries and agriculture.

Although that plume, coming from the largest source of polluted runoff flowing into Lake Erie -- the Maumee River -- tends to concentrate in northwest Ohio, it does not stay there.

In fact, recent satellite images show the algae mass moving slowly toward Pelee Island. Ultimately, it could end up in Lake Erie's central basin, sinking to the bottom as the algae die off, Reutter said.

The Maumee River is not the only culprit, however.

"A lot of nasty things are coming (into the lake) from the Detroit River," Reutter said, pointing to the lake's elevated mercury levels.