Researchers: Lake Erie algae likely done for year

CLEVELAND— The harmful algal bloom in Lake Erie started early this summer. But it was smaller than predicted, and scientists aren’t sure why.

It wasn’t a decrease in nitrogen or phosphorus, the two major nutrients that cause the mat of toxic bluegreen algae that plagues the lake’s western basin each year.

“It has nothing to do with the nutrients coming into the system,” said Chris Winslow, director of the Ohio Sea Grant at Stone Laboratory on the lake. “It’s all to do with lake dynamics.”

Meanwhile, Toledo officials say that three consecutive weeks of tests have found no toxic microcystin in raw water drawn from that city’s Lake Erie intake crib, meaning this year’s algae bloom is “It has nothing to do with the nutrients coming into the system. It’s all to do with lake dynamics.”

Chris Winslow, director of the Ohio Sea Grant at Stone Laboratory over.

University of Toledo algae researcher Tom Bridgeman agrees. He says the lake’s western basin is “out of the woods” after yet another summer of blooms. He doesn’t foresee any recurrences this year as the weather grows colder.

Toxins in Toledo’s Lake Erie-fed water system caused a crisis in 2014 that affected 500,000 area residents supplied by the city.

Scientists use six models to forecast the severity of a bloom, based on spring rainfall, water temperature, the amount of nutrients flowing into the lake, and more.

Wet and warm weather, along with calm wind, can cause a bigger bloom. However, the size of a bloom does not necessarily indicate how toxic it is.

This year, the Lake Erie forecast was for a 6 out of a possible 10 — less severe than last year but worse than 2016.

In 2017, the prediction was a 7, and the bloom was an 8 — considered a success by forecasters. They’ve been correct nearly all years except in 2016, when the bloom was more severe than expected.

This summer was hot. And water temperature in the western basin hit 70 degrees in May, according to Ohio Sea Grant.

“It’s a warm lake, a windy year, with the wind coming from different directions. All that mixing will play a role,” Winslow said.

Scientists from the University of Toledo, University of Bowling Green, NOAA and Sea Grant are all studying the data, considering wind mixing, wind direction, wave height.

Ohio aims to cut down the blooms, which hurt the environment and the economy because of less tourism dollars, by reducing phosphorus 40 percent by 2025. Phosphorus primarily comes from fertilizer and manure on farms in the watershed of the western basin.

Gov. John Kasich signed an executive order in July to “initiate aggressive new action” by state agencies to reduce nutrient runoff. The order targets eight watersheds with the highest levels of phosphorus and creates a management plan to control it.