A harmful blue-green algae bloom is still plaguing the Ohio River, and a Kentucky biologist says it doesn't look like that will change soon.
Mark Martin with Kentucky's Department of Environmental Protection says the algal bloom reaches from West Virginia past Louisville. He says colder weather won't kill it.
“Temperature has a bearing on it but I wouldn’t say that a cold snap would just end it. It's more likely in warm or hot weather and less likely in cold weather. But I’ve seen this in January.”
Martin says rain would help by raising the river and increasing water flow. He says the algae prospers in slow moving or still water.
Algae naturally occurs in waterways, but harmful blooms are the product of excessive runoff of nutrients like phosphorus and nitrogen, combined with sunny, warm conditions and low-flow water levels.
Martin says “When the flow is insufficient to mix the water, the water will stratify so the water up near the surface where the algal blooms occur will get continued sunlight."
He adds, "They don’t thrive in mixed water with current with eddies and things like that that would bring surface water down to the river bottom. They need to stay up near the top where the sunlight is.”
The Kentucky Department of Water (KDOW) received the first reports of an algal bloom on August 31, near Greenup. KDOW issued a recreational advisory for the Ohio River from the West Virginia border to the Meldahl Dam on September 4. That advisory was expanded to the Markland Dam on September 11, and again to the Cannelton Dam on September 18.
Martin says if people drink algae-contaminated water it can make them sick with gastrointestinal symptoms including nausea, vomiting, and diarrhea. Some people have reported breathing problems along with skin, eye, and throat irritation after contact with affected waters.
Some communities have adapted to keep drinking water safe for customers.
“Realistically, there are ways to manage this," Martin says. "The problem that it may incur for drinking water producers is cost. They have to buy and replenish activated charcoal on the front and back end of their treatment plant,” Martin says.
Greater Cincinnati Water Works already uses activated charcoal year round.
