They're back. Algae are growing in western Lake Erie as they do every year, posing a potential health threat to people and pets.

The National Oceanic and Atmospheric Administration monitors Lake Erie for harmful algal blooms. Each spring, it estimates how large and toxic they might become.

NOAA oceanographer Rick Stumpf tells WDET on a scale of 1 to 10 — with 10 being the worst — this year's bloom should be relatively mild.

"Right now, we're estimating between 2.5 and 4.5," he said.

WDET's Pat Batcheller joined The Metro to discuss NOAA's efforts to monitor harmful algal blooms in Lake Erie, and why their estimates could change.

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