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E. coli monitoring underway as 2021 recreation season heats up

E. coli testing sign in Cadillac, MichiganThe water may still be cool, but the summer-like temperatures and humidity have us thinking about plunging into the nearest lake. As you are getting ready for your day on the water, your safety is EGLE's priority.

EGLE's Water Resources Division (WRD) is responsible for monitoring our lakes, rivers, and streams for E. coli, which is used as an indicator of other pathogens. These pathogens, such as Giardia and Cryptosporidium, originate in fecal matter but can cause severe illness if they enter your body through accidental ingestion or contact with your skin. Sources include untreated human waste from failing septic systems and illegal connections from home sewer systems to surface water. Other major sources of fecal pollution include livestock, pet waste, and nuisance levels of wildlife.

Michigan's Total Body Contact recreation season began on May 1st and extends through October. During this time, the water quality standard to protect Michigan's residents and visitors from high levels of pathogens during recreation is a daily maximum of 300 E. coli per 100 milliliters (mL).

This year, EGLE is monitoring over 140 sites on rivers throughout the state for E. coli to determine if the water is safe for recreation and to help identify pollution sources. These sites are located from Keweenaw Bay to Benton Harbor, and include parts of the Cass, Bad, Grand, Muskegon, Paw Paw, and Red Cedar rivers. The results of our monitoring are shared with the local health department and previous data are available to the public in Michigan's E. coli Pollution and Solution Mapper

Each year, the public has an opportunity to guide where we monitor through our targeted monitoring request process. If you have concerns about water quality, or ideas about future E. coli monitoring, please visit the WRD's targeted monitoring request website.

Visit the EGLE E. coli website for general information, Check out our Guide for Homeowners, and watch the MI EnviroMinute video on the subject.

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