Karen Vandeneeden lives on the shore of Grand Lake St. Marys and jokingly refers to it as her "front yard." She says she loves to fish, but won’t eat her catch — although it’s not out of fear of toxic algae.

"I don’t like cleaning them any more," she laughs.

The State of Ohio says it is still safe to eat the fish from the lake, but state officials warn against swimming or wading in it in light of an algae bloom that sprang up in May. At one point last year the state warned against any contact with the water.

"Last year the stench was so bad, I started dry heaving so bad, I had to get out," Vandeneeden said.

On Thursday, the state will begin treating the water with aluminum sulfate and another chemical in hopes of choking the algae’s food supply. But, that’s only part of the solution. The state is also working with farmers to reduce fertilizer runoff into Ohio’s lakes.

So, are Ohio’s lakes safe?

"Ohio’s lakes are safe, you bet," said Scott Fletcher, director of special projects for the Ohio Department of Natural Resources.

"Our goal is to be protective of human health," he said.

By Tom Bosco, ABC News