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We’re commemorating the 50th anniversary of the Clean Water Act.

This monumental piece of legislation and the burst of federal support for water infrastructure that followed revived polluted waterways across the United States – especially here in Philadelphia. 

Follow along as we honor this milestone with history, events, and ways you can support the ongoing work of protecting and restoring our rivers and creeks!


Before the act was passed in 1972, Philadelphia’s waterways were polluted with sewage, trash, oil, and toxic industrial waste. We’ve made a lot of progress in the last 50 years.


  • During World War II, the Delaware River was so polluted that personnel of naval vessels complained the odor made it impossible for them to eat while docked there. A US Army pilot claimed he could smell the river from 5,000 feet in the air.
  • Hydrogen sulfide fumes from decomposing bacteria in the river were so noxious that some shipping vessels refused to dock in Philadelphia because of the smell.
  • The river’s water was so foul that it would turn the paint of ships brown as they traveled through or were docked for any period of time.

…and Now

  • The construction, operation, and subsequent treatment upgrades at our three Water Pollution Control plants are responsible for significant water quality improvements in the Delaware and Schuylkill Rivers. 
  • Today our rivers support diverse aquatic habitats, with some species once considered threatened or endangered now thriving along Philadelphia waterways, thanks to improvements that were made possible through Clean Water Act funding. 
  • In 2021, the Philadelphia Water Department’s three Water Pollution Control Plants treated an average of 444 million gallons of wastewater and stormwater per day, for an annual total average of approximately 162 billion gallons.
  • Since Green City, Clean Waters was officially adopted as Philadelphia’s plan to address the issue of combined sewer overflows in 2011, we have had tremendous success. At the start of 2022, we were officially managing stormwater from nearly 2,200 acres of impervious surfaces using green infrastructure – all adding up to a more than 3-billion-gallon reduction in the annual combined sewer volume.