Report: Potentially unsafe E. coli levels found at 359 of 653 Pennsylvania river sites
A statewide review by PennEnvironment Research and Policy Center found more than half of monitored river sites recorded E. coli at potentially unsafe levels during 2024–2025.
The PennEnvironment Research and Policy Center found that 359 out of 653 monitored locations across Pennsylvania rivers — about 55% — had “potentially unsafe levels” of E. coli bacteria on at least one day during monitoring periods in 2024 and 2025. The findings underscore widespread water-quality concerns for rivers used for recreation and other public uses.