ST. MARYS — Grand Lake is cleaned up and ready for the summer tourist season, thanks to aggressive efforts by the Ohio Department of Natural Resources.
A new dredge that’s been in service there for the past year named “Brutus” has increased the amount of sediment pulled from the lake about fourfold.
“Dredging not only removes the stuff that’s at the bottom to keep at a depth for boating and recreation and for fish health, but it also removes that nutrient-rich sediment that has built up over the years that’s at the bottom of the lake that can feed algae in the summer,” said Mark Bruce, ODNR spokesperson.
Swimming at the lake was prohibited in the summer of 2010 after a toxic algae bloom had spread there.
“The last couple years have been kind of typical; 2010 was an unexplainable year,” said Brian Miller, parks manager at Grand Lake St. Marys State Park. “We had a different species of algae. Since then, we’ve been dealing with the same species we’ve dealt with for an eternity here.”
“That was a wakeup call for everybody,” Bruce said. “Since then, we’ve put in a nutrient management plan … and we’ve nearly quadrupled the amount of sediment we’ve taken out of the lake because we researched it, we studied it, and realized we got to get the stuff out if the algae feeds on it. And removing the sediment is one way to do that.”
Because of the variety of efforts, the water quality has significantly improved. Last year, the 57-ton dredge pulled up 289,000 cubic yards of sediment from the lake.
There are plans for the sediment, too, to keep the water even cleaner. A wetland is being built near Prairie Creek to act as a barrier for some of the agricultural runoff, which is usually to blame for the developing algae blooms.
“Those wetlands act as a filter for agricultural runoff,” Bruce said.
While the park does not do a headcount of its visitors, Miller said the bed tax from local hotels increased last year, an indicator that more people had likely visited the lake. That was the first time since 2007 that the bed tax numbers increased.