Correction: An earlier version of this story incorrectly stated that a 2011 algae bloom shut down Toledo's water system. It also incorrectly attributed to Dr. Sonia Joseph-Joshi a statement that this year's blooms are not expected to affect the system.
A growth of harmful algae on Lake Erie has grown larger than last year's bloom, according to the National and Oceanic Atmospheric Adminstration's Lake Erie Harmful Algal Bloom Bulletin.
Sonia Joseph-Joshi, Outreach and Communications Specialist at NOAA's Great Lakes Environmental Research Laboratory, says swimmers should avoid the surface scum along the Michigan and Ohio shorelines.
"If a dog or a human is exposed to a scum our recommendation is to certainly just rinse off and wash off with soap," Joseph-Joshi says.
Models forecast that the bloom will move west toward the Michigan shoreline. Updates are available through local health departments and the Ohio EPA harmful algae bloom web site.