[USA] Ohioans are used to hearing about toxic algae forming on Erie, Buckeye and other lakes across the state each summer. But not the Ohio River, which currently has a bloom nearly 650 miles long.
It started in August, when tests at drinking-water plants in eastern Ohio and West Virginia showed levels of microcystin, the toxin produced by a particular type of algae. It’s a neurotoxin that can damage livers and kill pets.
Now, the bloom is causing problems for drinking water and recreation along more than two-thirds of the Ohio River’s length.
“It’s unprecedented,” said Greg Youngstrom, an environmental specialist at the Ohio River Valley Water Sanitation Commission, which oversees the health of the river. “What we think is going on is that the conditions have just set up perfectly for this.”
After a rainy June and July, August was mostly dry. The river, laden with runoff from the land that surrounds its watershed in New York, Pennsylvania and Ohio, slowed almost to standstill.
The weather was warm, the river wasn’t moving and the algae had plenty of food. The bloom began to spread downriver, reaching Portsmouth, then Cincinnati and Louisville, Ky.
By Friday, 44 days after it was first spotted, the bloom had flowed well into Indiana.
It’s an unprecedented problem: Until this summer, the largest algae bloom on the Ohio River spanned about 30 miles and lasted about 10 days.
Sanitation commission scientists aren’t sure what specifically caused this algae bloom to form and grow.
Microcystis feed on phosphorus, a key ingredient in human waste, manure and some fertilizers. Farm runoff, overflowing septic systems and failing municipal wastewater lines can contribute to microcystin blooms.
There always is some level of microcystin and other algae in the Ohio River, but its fast flow usually keeps blooms from forming.
Scientists have been monitoring the algae and collecting data that they will analyze this winter to try to understand what started the bloom. They also have been warning people to avoid the water.
Last weekend, athletes participating in the eighth-annual Great Ohio River Swim were supposed to dive into the Ohio River near Cincinnati for a swim to Kentucky and back.
The event was postponed until next Saturday, but it still will depend on the algae.
“It’s disappointing,” said race director Jon-
athan Grinder. “But it’s a no-brainer. We have to keep our athletes safe.”
The toxin in the Ohio River is the same type that contaminated Toledo’s drinking water in 2014, making it unsafe for several days for about 500,000 customers.
Water-treatment plants along the Ohio River have been monitoring for and treating water tainted with microcystin.
Greater Cincinnati Water Works, which supplies drinking water to customers in Hamilton, Butler and Warren counties in Ohio and Boone County in Kentucky, is spending about $7,500 a day to keep the water safe from algae toxins.
Tests along the river and reported to the Ohio Environmental Protection Agency show the amount of toxin in the river is now declining in spots.
On Sept. 14, for example, microcystin levels near Cincinnati were about 4.5 parts per billion. By Sept. 28, they’d dropped to 1.6 parts per billion.
Heidi Griesmer, a spokeswoman for the Ohio EPA, said the agency is working with smaller water-treatment plants to make sure drinking water is safe. So far, she said, tests have shown none of the toxin in drinking water.
As temperatures drop, it’s likely the bloom will die off.
The ongoing Hurricane Joaquin also could help. A lot of rain could speed up the flow of the river and disperse more of the bloom.
It could stir up more mud, too, which would help block sunlight, which algae need to grow.
“What we really need is a change in conditions,” Youngstrom said.
Photo: PATRICK REDDY | THE CINCINNATI ENQUIRERAn algae bloom lurks at the confluence of the Ohio and Licking rivers. Covington, Ky., is in the background.
View original article at: Toxic algae bloom now stretches 650 miles along Ohio river