You may have seen Toledo in the news the past few days as it worked to provide safe tap water for as many as 400,000 people. Fortunately, on Monday the two-day ban was lifted when it was determined the water met Ohio EPA standards. The ban was due to increased levels of the toxin microcystin, produced by blue-green algal blooms which occur in warm waters found in freshwater lakes, ponds and also in marine waters around the world. As the algae die, the toxin is released into the water. For this reason boiling does not make the HAB water safe to drink.

Photo credit: EarthObservatory.NASA.gov (8/06/2014)

Wind conditions on Saturday (August 2) kept the bloom concentrated near the mouth of the Maumee River and apparently large amounts of the bloom were taken in at the Toledo water intake. When wind conditions changed, the bloom appeared to move away from the mouth of the Maumee River and out into the western basin of Lake Erie. The bloom is not large and remains within forecast parameters, but it is obviously very toxic and in a very bad location. Unfortunately, it is likely to persist well into October, when cooler weather arrives, and will not reach its peak until September.

Ohio Sea Grant and the Ohio Sea Grant Extension Program professionals have been working to address the Harmful Algal Bloom (HAB) issue for years. Factors favorable to HAB formation include highly fertile water, sunny weather, warm temperatures, and selective grazing by zooplankton and or zebra/quagga mussels. Selective grazing removes the “good” algae and leaves the cyanobacteria that make up the HAB.

These short (1-4 page) fact sheets provide more information:

Harmful Algal Blooms in Ohio Waters

10 Things I Should Know About Algal Blooms

For more information on the Ohio Sea Grant Program and the Ohio Sea Grant Extension Program professionals, go here.

(Submitted by Frank Lichtkoppler, Professor & Extension Specialist, Ohio Sea Grant Program)