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Several Philadelphia-area rivers and creeks fail to meet goals of the federal Clean Water Act for swimmable waterways, according to a new report from PennEnvironment.
Fecal bacteria pollution detected in waterways like the Delaware River and the Brandywine Creek mean water recreation is unsafe during many days of the year, the report says.
“The concern is that when folks are swimming or participating in other recreational activities in contaminated water, whether that’s paddling, whether that fishing, whether that’s letting their dogs wade into the creek, then you’re coming into contact with water that can get you sick,” said Stephanie Wein, clean water and conservation advocate for the PennEnvironment Research and Policy Center.
PennEnvironment evaluated federal and state water quality reports at 653 locations across Pennsylvania rivers, streams and lakes between 2024 and 2025. The environmentalists found potentially unsafe contamination levels on at least one day at about 55% of the sites.
Almost 40% of the areas tested had potentially unsafe levels of fecal contamination on at least one-quarter of the days on which testing took place.
Along the Philadelphia section of the Delaware River, E. coli frequently exceeded unhealthy levels. The environmentalists point to combined sewer overflows as the cause of the contamination.
Swimmable waterways have long been the goal of the Clean Water Act, passed in 1972. But more than 50 years after its passage, older industrial cities such as Philadelphia struggle to reach that level of cleanliness because of outdated sewer systems.
Unlike modern infrastructure, which utilizes separate piping systems, older sewer systems send stormwater and sewage through the same underground pipes.
During heavy rain, these older systems can overflow, spilling raw sewage into the region’s rivers and streams.
Concerning levels of bacteria were also reported at the base of the Schuylkill River and the Northeast Philadelphia section of Pennypack Creek.
In comparison, most of Bucks County, the Lehigh Valley and the Poconos region meet health-based water quality standards, according to PennEnvironment.
The Brandywine Creek in Chester County, which is often used for kayaking and tubing, contained E. coli that exceeded levels set by the U.S. Environmental Protection Agency to guide no-swim orders on one of the five days tested in 2024 and 2025.
Swimming in water contaminated with E. coli can cause gastrointestinal illness, as well as respiratory disease, ear and eye infections, and skin rashes.