Chippewa Lake has reopened to the public and all water contact warnings have been lifted following a significant decrease in levels of algal toxins, the Medina County Park District said Monday.
Test results from samples taken Nov. 30 and Dec. 7 revealed toxin levels of 5.76 parts per billion and 4.571 parts per billion, respectively, down from a high of 58 ppb on Nov. 10.
The Ohio Department of Health requires warnings to be issued advising young children, pregnant and nursing women, senior citizens, and pets to avoid water contact when toxin levels reach 6 ppb. When levels exceed 20 ppb, the lake must be closed.
The warnings first went into effect Sept. 16. The 330-acre lake had been closed to the public since Oct. 28. State guidelines require two consecutive tests showing acceptable toxin levels before lake closure restrictions and water contact warnings may be lifted.
The district blamed the algal bloom on the microscopic organism cyanobacteria.
“This species is more shade tolerant and cold tolerant than other species, which is why the bloom continued so late into the year,” park district Natural Resource Manager Jim Spetz said in a prepared statement.
The park district said it would continue the monitoring on an as-needed basis.