How the Clean Water Act Fixed the Delaware River’s Pollution Problem

WHYY | January 23, 2019 | Energy & Environment
Oxygen levels in the river began to increase after cities like Philadelphia began treating wastewater

Credit: Emma Lee/WHYY
A cormorant perches on a log in the Brandywine Creek.
President Donald Trump came into office promising to roll back environmental regulations.
The Trump administration has weakened, delayed or is working to roll back at least four regulatory protections related to water.

The backbone of the nation’s current water quality regulations date to the early 1970’s with passage of laws like the Safe Drinking Water Act and the Clean Water Act. Before the Clean Water Act of 1972, parts of the Delaware River below Trenton were considered “dead zones.” There were no fish because discharges of organic materials from slaughterhouses and untreated sewage caused the oxygen levels to drop. Microbes and bacteria thrived on the organic material and as a result, consumed all the oxygen, leaving none for the fish.

The CWA helped transform the Delaware River from a “stinky ugly mess” into a year-round attraction that hosts beer gardens, yoga classes, pleasure boats and is now lined with million-dollar houses, said Philadelphia’s water commissioner Deb McCarty.

To get the fish to return, the Clean Water Act ushered in an age of biological science to treat wastewater — using microbes and oxygen to eliminate the bacteria in a controlled setting.

Read the second part of “Reviving the River,” a series by WHYY, a content partner of NJ Spotlight.