Grand Lake St. Marys, located near Celina in northwest Ohio, is the other lake with an advisory and faces much worse conditions than Buckeye Lake.
Brian Miller, manager of Grand Lake St. Mary’s State Park, said recent samples at its three beaches showed microcystin toxin levels of 3.3, 4.0 and 5.1 parts per billion, respectively, down from more than 20 for all three beaches two weeks ago.
Celina, however, found levels of 33.7 parts per billion this past week and 23.7 this week, Miller said.
The World Health Organization has set the acceptable level at 20 parts per billion for an adult, but Ohio has drafted a policy setting the maximum of 6 parts per billion, allowing children to swim safely.
It’s the third year in a row, Miller said, they have had to advise against swimming at the state’s largest inland lake, which has a green tint to it.
"It’s had a huge impact on tourism here," Miller said. "You have a huge tourism economy here. We’re at a minimum of 20 percent off our tourism revenue, and some are down 40 to 60 percent."
The majority of Grand Lake St. Mary’s watershed is agricultural, so runoff from farming activities could account for most of the increased phosphorus in the water, Miller said.
The problems began for Grand Lake St. Mary’s in 2009, just before Memorial Day weekend, when the first advisory was posted. In 2010, the advisory went up in mid-June. Both years, the advisory lasted the entire summer.
Residents in the area are being encouraged to do soil samples on their land and adjust application of fertilizer accordingly.
"Most lawns do not need phosphorus but do need nitrogen," Miller said.
The lake has been dredged, Miller said, to remove carp, which are known to stir up bottom sediment, contributing to the problem.
More testing, advisories
A national lake sampling at Grand Lake St. Mary’s in August 2007 triggered the increased statewide testing for the toxin. The results from that test were delayed.
"We got the results in April 2009," Miller said. "Last year, it was a different algae species. It was to the point the advisory signs said not to launch watercraft."
As a result of the discovery at Grand Lake St. Mary’s, testing efforts expanded beyond E. coli at lakes statewide.
Lindsey said that in her 28 years, 2010 was the first time water samples were taken for these toxins.
"We at ODNR don’t think toxins are any more now, but because of St. Mary’s, it’s a closer scrutiny," Lindsey said.
"Since the situation at Grand lake St. Mary’s was so catastrophic, it’s opened up a lot more testing and more information fed into us now."
In June and July 2010, 18 Ohio lakes had harmful algae blooms, but Buckeye Lake was not on the list.
"This year doesn’t appear as bad as last year," said Scott Fletcher, customer services and safety manager with Ohio State Parks. "In Ohio, we’ve never really looked for this before, prior to 2009. Before 2009, we didn’t see it or it was not reported."
By Kent Mallet, Zanesville Times Recorder