A massive pipe that moves millions of gallons of sewage has ruptured and sent wastewater flowing into the Potomac River northwest of Washington, DC, polluting it ahead of a major winter storm that has repair crews scrambling.

DC Water, which operates the sewer system, is hooking up pumps to divert sewage around the rupture and allow crews to make repairs. It has cautioned people to stay out of the area and to wash their skin if exposed.

The spill was caused by a 72-inch diameter sewer pipe that collapsed late Monday, shooting sewage out of the ground and into the river. DC Water spokesperson John Lisle said the utility estimates the overflow at about 40 million gallons each day — enough to fill about 66 Olympic-size swimming pools — but it’s not clear exactly how much has spilled into the river since the overflow began.

Signs warn the public to stay away

“Oh, my god, the smell is horrific,” said Dean Naujoks, the Potomac Riverkeeper and part of an environmental nonprofit. “It’s such high concentrations of sewage that just grabbing a sample is a public health risk.”

Associated Press video from the scene showed signs posted near the river that read “DANGER” and “Raw Sewage” and warned people not to enter the area. Naujoks and another man donned protective gloves to take samples of water from the river to test for E. coli and other bacteria. Small bits of debris could be seen floating in some of the sample bottles.

The spill occurred in Montgomery County, Maryland, along Clara Barton Parkway, which hugs the northern edge of the Potomac River near Chesapeake and Ohio Canal National Historic Park.

Crews are removing lock gates on the C & O Canal and will set up pumps to divert the sewage into the canal, rerouting it away from the river and back into the sewage system downstream. The pumps have enough capacity to capture all of the sewage flow in dry weather, said Lisle, but they could be overwhelmed by a surge in stormwater. Crews will work through the weekend, when a bad winter storm is expected, Lisle said, and they hope to have the bypass set up by Monday.

The spill does not impact drinking water, which is a separate system, DC Water said.

Naujoks said the spill is happening at a time when the river is low. He went out to look at it Wednesday and was “kind of stunned.”

“Sewage is just bubbling up like a small geyser, maybe 2, 3 feet into the air,” he said. “Sewage water is running in every direction.”

The District of Columbia Department of the Environment did not immediately respond to a request for comment, including whether it is testing the river’s water.

Damaged pipeline is one of several sections identified for repair

DC Water knew the pipeline was deteriorating, and rehabilitation work on a section about a quarter-mile from the break began in September and was recently completed, Lisle said. Repair work on additional “high priority” sections of the pipeline is expected to start later this year, according to the DC Water website.

The pipeline, called the Potomac Interceptor, was first installed in the 1960s.

There’s a huge funding gap for water infrastructure in the US, said Gary Belan, a senior director with American Rivers, an environmental organization that advocates for clean waterways.

“I know a lot of the wastewater folks are trying to catch up as best they can, but this is something we see and will continue to see, where these pipes fail and these massive sewage dumps occur,” Belan said. “This is why we can’t defer maintenance of our wastewater infrastructure. Too often, we’re dependent on these disasters to prod us forward.”

Washington Mayor Muriel Bowser, speaking at a press conference declaring a snow emergency for the impending storm, said authorities there were aware of the sewage spill “but I can’t give you an intelligent response right now.” She said DC officials would be more forthcoming as soon as they could.

Kelly Offner, a US Environmental Protection Agency spokesperson for the mid-Atlantic region, said the agency was coordinating with DC Water, the Maryland Department of the Environment and other federal, state and local authorities to assess the impact on the environment from the Potomac Interceptor sanitary sewer overflow. The federal agency oversees DC Water’s sewer operations under a 2015 federal consent decree.

“DC Water has provided daily updates since the overflow was discovered on January 19, 2026, and has been coordinating efforts to contain the overflow, monitor environmental impacts, and communicate with the public,” Offner said in an emailed response to questions.

An EPA survey of wastewater infrastructure needs from 2022 estimated that the District of Columbia needs roughly $1.33 billion to replace or rehabilitate structurally deteriorating sanitary or combined sewers within the next 20 years.

Nationally, hundreds of billions in infrastructure investment is needed over the next two decades for clean water problems like aging sewer pipes. In other places where sewer breaks are persistent, it can lead to backups into homes and regular flooding. (CNN)

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