Monday, September 9th, 2019
Lake's better, but not great
Microcystin down, expect to spike
By Sydney Albert
CELINA - Grand Lake had its lowest microcystin levels in seven years this summer, but Lake Improvement Association president Nick Rentz cautioned that a seasonal spike is still expected this fall.
"Our microcystin levels will spike this month. It happens all the time, it doesn't happen just here, it happens at Lake Erie as well," Rentz said during Saturday's LIA meeting.
Rain that tends to fall in September and early October wash more nutrients into the lake, Rentz explained. While the spike in nutrient-loading would not be near the level the lake usually experiences in the spring, he said the algae would still be able to grow with the added nutrients.
"It'll take the very smallest amount of nutrients here in the fall and know that its life cycle is about ready to come to an end and say, 'I gotta get to work.' So you'll see a bloom in the fall."
When looking at the spike in microcystin levels that would come with a fall algae bloom, lake caretakers and activists should not compare the levels to those from earlier in the summer. Instead, Rentz said, the levels need to be compared with microcystin levels from the same time period in previous years.
"If this thing spikes to 50 or 60 (micrograms per liter), was it 70 last year?"
Rentz said Wright State University-Lake Campus professor Stephen Jacquemin would speak at LIA's October meeting to discuss how the expected spike in the coming month compares with what was seen last year.
In other business, testing of microcystin levels at the West Beach will continue, and plans to install four additional diffusers will proceed.
Before Labor Day weekend, Grand Lake St. Marys State Park director Dave Faler told the newspaper that initial tests measuring microcystin levels at West Beach showed toxin levels were low enough to remove the "no contact" water advisory signs. However, the signs will remain up as officials continue testing to ensure the results are consistent.
Three samples were taken from West Beach's water since the completion of the beach's renovation project, Faler said in August. Two samples showed microcystin levels below 6 micrograms per liter, low enough to remove the "no contact" signs at the beach.
However, due to the small amount of data, the signs would not be removed just yet, Faler said. Officials hope the results are due to the work done at the beach, but other timely factors, including recent rains, could affect the results. He said rains could be diluting the water and making levels lower than they might normally be.
LIA officials are still looking for volunteers and cookie donations for the Sept. 11 Kids Fishing Derby at the East Beach. It's estimated that more than 300 people - counting children and chaperones - will attend the event.
