The creek running through two of Montgomery's most popular parks carries E. coli bacteria that can spike to dangerous levels after rainstorms, the city's Environmental Advisory Commission warned in an advisory published July 10.
The North Branch of Sycamore Creek at Pioneer Park and Dulle Park hit "Unacceptable" contamination levels when volunteers tested the water in April 2026 following several days of rain, according to the advisory written by commission member Greg Brodrick and posted on the city's official website.
The water looked clean. It wasn't.
"Be mindful that a creek can appear clear, odor-free and visually clean and still have unsafe bacterial levels," Brodrick wrote in the advisory.
The advisory arrives as summer heat drives families and children to wade in the shallow creek.
What's in the water
E. coli is an indicator of fecal contamination from humans or animals, according to the advisory. Common sources along the creek include dog waste from neighborhoods and parks, goose droppings near ponds, and deer and raccoon waste in wooded areas.
The creek's watershed starts at Summit Park in Blue Ash and collects runoff from Interstate 71, city streets, and parking lots before flowing through Montgomery. That urban runoff contributes to contamination even when the water appears pristine.
High chloride levels from winter road salt also linger in the creek months after salting season ends.
Monthly testing results
Volunteers from the Izaak Walton League of America's Cincinnati Chapter test the creek once a month as part of Ohio EPA's Credible Data Program. The overall water quality index for the first three months of 2026 rated "Good" in March, "Good" in April, and "Fair" in May.
The composite ratings can obscure individual spikes. The April overall score was "Good" even though E. coli tested at "Unacceptable" levels after rain during the same month. When water flow is low and dry weather persists, contamination tends to drop.
How to stay safe
The city recommends park visitors take these precautions:
- Do not swallow creek water
- Keep creek water away from open wounds and eyes
- Wash any skin that touches the creek with soap and clean water
Reporting pollution
Residents who notice unusual colors, odors, or other signs of pollution in the creek can call the City of Montgomery Public Works Department at 513-792-8355 or the Hamilton County Storm Water District Hotline at 513-946-7000.
