The state is once again recommending that people and pets avoid swimming and wading in Ohio's largest inland lake, Grand Lake St. Marys, as levels of an algae-produced toxin rise.
Public health officials are also encouraging boaters and jet skiers to understand the risk of exposure to higher levels of the toxin microcystin, which can include rashes, hives and skin blisters.
Craig Butler, Ohio Environmental Protection Agency director, said Tuesday that the higher toxin levels are likely the result of record rainfall this year.
Similar signs went up last year at Grand Lake St. Marys, 20-square-mile lake between Dayton and Toledo.
Efforts to clean up the lake date back several years. A toxic algae bloom in 2010 hurt the region's tourism and highlighted problems from farm phosphorous runoff.