ZANESVILLE, Ohio (AVC News) — A bacteria advisory remains in effect at the swimming beach at Dillon State Park after the latest water sample showed extremely high levels of E. coli.
According to the Ohio Department of Health, the advisory has been in place since May 29 due to elevated bacteria levels. As of this week, the swimming area has been under advisory for 68 days.
The most recent water sample, collected July 22, measured 19,900 colony-forming units (cfu) of E. coli per 100 milliliters of water. Previous samples this year ranged from 313 cfu/100 mL on July 8 to 2,600 cfu/100 mL on June 10.
E. coli is used as an indicator of fecal contamination in recreational waters. Elevated levels can increase the risk of illness for swimmers, prompting state health officials to issue swimming advisories.
The source of the elevated bacteria levels has not been identified. Potential causes can include stormwater runoff, wildlife, livestock, failing septic systems, or sanitary sewer overflows.
The advisory remains in effect until additional testing shows bacteria levels have returned to acceptable limits. Visitors are urged to avoid swimming at the beach while the advisory remains in place.
Last Updated on August 5, 2026 by AVC News
