PennEnvironment Research & Policy Center released a report last week on testing of rivers and streams across the Commonwealth. Results indicated that 55% of the 653 monitored sites experienced at least one day of potentially unsafe levels of E. coli bacteria during 2024 and 2025. 39% of these locations had potential unsafe fecal contamination during at least one-quarter of the tests.
Common causes of fecal indicator bacteria like E. coli include sewage spills and overflows, stormwater runoff, and failing septic systems. Around 87 million cases of illness every year are associated with recreation in U.S. waterways.
Some of the most contaminated waterways in the state include the Philadelphia section of the Delaware River, Pittsburgh’s Saw Mill Run, and parts of the Brandywine Creek, with unsafe levels of bacteria found on 90-100% of testing days.
Tests of monitored sites in Lehigh and Northampton Counties revealed low levels of unsafe bacteria. Sites in the Lehigh and Delaware Rivers in Northampton County exceeded safe levels on one day of testing.
Neighboring Bucks and Berks Counties also saw fewer numbers of unsafe test days, while Carbon and Schuylkill Counties to the Lehigh Valley’s north have multiple sites each with higher levels of contamination.
Waterways may have also experienced contamination on days without testing.
Although the EPA reported in 2024 that the nation will need at least $630 billion in wastewater and stormwater improvements over the next two decades, Congress provided states with only 11% of this annualized need this fiscal year.
PennEnvironment is urging local, state, and federal governments to invest in new infrastructure that prevents sewage spills, protect and restore wetlands and streamside buffers that naturally filter pollution, expand water quality monitoring, and more.
