This story was originally published by Inside Climate News and is reproduced here as part of the Climate Desk collaboration.

The warning signs were years in the making. And yet, regulators failed to heed the writing on the wall, according to Dean Naujoks.

An investigator with the Potomac Riverkeeper Network, Naujoks spent three years documenting what he calls a systemic failure that culminated in dual environmental catastrophes now threatening the health of the entire Potomac River system, which is already stressed.

In January, a 60-year-old sewer pipe known as the Potomac Interceptor, running along the Maryland shoreline of the Potomac, collapsed near the Clara Barton Parkway corridor in Montgomery County, releasing an estimated 243 million gallons of raw sewage into the river over approximately three weeks.

But even before that spill, another crisis had already begun to unfold elsewhere in the watershed. At Joint Base Andrews in Prince George’s County, a fuel system failure on Dec. 11 led to thousands of gallons of jet fuel entering the headwaters of Piscataway Creek, a tributary that feeds directly into the Potomac. The leak continued for months before state regulators were notified.

Stretching more than 400 miles, the Potomac River is a source of drinking water for more than 5 million people in the Washington, DC, metropolitan area. In April, American Rivers, a conservation nonprofit, named it the most endangered river in the country, citing both the sewage spill and the rapid expansion of data centers.

Piscataway Creek, an 18.6-mile tributary of the Potomac, begins at the edge of Joint Base Andrews and slips back into the Potomac at Fort Washington Park. Its name derives from the indigenous Piscataway people, who’ve stewarded these waters for thousands of years and maintain a living relationship with the creek and the river to this day.

Naujoks believes neither crisis happened in a vacuum.

He first began tracking contamination in Piscataway Creek around 2022, after reports emerged of tainted fish. A researcher named Pat Elder, Naujoks said, who worked for an organization called Military Poisons, which investigates PFAS contamination at military bases across the country, initially raised the alarm.

PFAS (per- and polyfluoroalkyl substances) are chemicals used in products ranging from kitchen items to military firefighting foam and are linked to cancers, immune disruption and reproductive harm.

When representatives from the Maryland Department of the Environment (MDE) tested the creek, they found the highest PFAS levels in any fish in any stream in the state. Among species tested was a sunfish from the creek that registered PFAS levels 1.4 million times higher than the EPA’s own standard for safe drinking water. The source of the contamination was the military’s practice of dousing jet fuel fires with........

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