Algae blooms have started in western Lake Erie, and researchers say the unusually warm weather may make things worse.
Scientists predict the bloom will be smaller than it was last year, when large swaths of the lake were colored a sickly green. But a federal government forecast says it still could be one of the four or five worst blooms since 2002.
The peak of the bloom generally occurs in late August or early September.
Fertilizer runoff is a major contributor to the blooms, so researchers study rain patterns. They say the period from March through June was wetter than average, with some thunderstorms.
That means more phosphorus was running into the Maumee River basin and the western end of the lake. That section is susceptible to blooms because it's shallow and warm; temperatures have already topped 80 degrees in some areas.
Tom Bridgeman of the University of Toledo says blooms appearing now could be the onset of the main bloom. In other summers, there was a break between the blooms.
“We often see a mini-bloom first. But what we're seeing now is more than I've ever seen in June,” Bridgeman told the Toledo Blade. "It's persisted for at least two weeks and it's getting bigger. This year could be different.”
In addition to being unsightly, the algae can be toxic. In 2014, Toledo residents lost access to tap water when the city water intake was contaminated.
And in a July 2 bulletin, NOAA warns: Keep pets and yourself out of the water in areas where scum is forming.