06/09/2026
Warm weather is a time when tiny plant-like organisms—algae and cyanobacteria—are more likely to overgrow in rivers, ponds, and lakes. These overgrowths, called algal blooms, can sometimes have foam, scum, or thick layers on the surface, or can look and smell bad. Algal blooms can also make the water appear green, red, brown, or blue. When they contain toxins that affect the health of people, animals, and the environment, they are known as harmful algal blooms (HABs).
You can’t tell if a bloom is harmful just by looking at it, and not all blooms are easy to see. When in doubt, stay out! Pets are susceptible to the toxins in the algal blooms too!
To monitor your favorite beach for any health advisories, visit: https://publicapps.odh.ohio.gov/beachguardpublic/