More than a month after the collapse of the Potomac Interceptor (PI), local and federal agencies are collaborating on repair and mitigation efforts, all aimed at ensuring that the PI is fully operational and overflow cleaned up by the middle of March.
This development comes not long after the Trump administration approved D.C. Mayor Muriel Bowser’s request for federal disaster assistance. The U.S. Environmental Protection Agency (EPA), along with other federal agencies, are now joining in on efforts to protect the east coast’s fourth largest river.
“The Potomac Interceptor collapse and overflow is a sewage crisis of historic proportions,” EPA Administrator Lee Zeldin said in a Feb. 21 statement after the Federal Emergency Management Agency, otherwise known as FEMA, announced disaster assistance. “Never should any American family, community or waterway have to experience this level of overflow.”
Last month, during the Rev. Dr. Martin Luther King Jr. holiday, DC Water became aware of the PI break via a camera at a nearby odor control facility. From that moment, the agency coordinated a response with the National Park Service that included the use of bypass pumps to move wastewater from around the break site and back into the Potomac Interceptor.
Despite complications caused by “snowcrete” and freezing temperatures, local response went on as planned, with bypass pumps taking 60 million gallons of wastewater per day away from the Potomac River by the latter part of January.
Other steps included excavation of a large rock dam that impeded pipe flow; that process required the construction of an additional pit upstream, which resulted in 130 million gallons of daily pumping capacity. With the EPA as the lead federal government agency in response efforts, local authorities in the D.C. metropolitan region have another level of support in the aftermath of an unprecedented infrastructure problem.
Amid President Donald J. Trump’s feud with Democratic Maryland Governor Wes Moore about the PI collapse, such support, however, may come at a price. In its communique, the EPA claimed that, before last week, neither the District or Maryland responded to its offers of support.
“The Trump EPA stands ready, motivated, and highly capable to step in and correct this situation,” Zeldin said. “I have full confidence in Assistant Administrator Jessica Kramer’s tremendous ability to serve as senior response officer. Together, we will work transparently, collaboratively, and efficiently to fulfill President Trump’s desire to quickly end this disaster and prevent it from being repeated.”
On Feb. 21, FEMA announced the availability of emergency disaster assistance for the District. This came days after D.C. Mayor Muriel Bowser (D) declared a state of emergency and requested federal support in the form of a presidential emergency declaration.
Other requests made by the Bowser administration included: reimbursement of repair and remediation costs; interagency coordination with FEMA and other federal agencies to affected areas; and additional federal technical and testing assistance. Long-term asks, made not long after the cancellation of a $2.3 million FEMA grant dedicated to the Blue Plains Floodwall project, focused on federal government support for D.C.’s Clean Rivers Project, the acceleration of U.S. Army Corp of Engineers’ repairs to the Washington Aqueduct, and collaboration between the National Parks Service (NPS) and DC Water to repair affected parts of the C&O Canal and surrounding federal lands.
By Friday, when it was yet to be determined whether the federal government would provide assistance, Bowser emphasized the importance of an all-hands-on-deck approach to PI repair and waste water mitigation.
“If things upriver aren’t taken care of well, it does impact the perception of the mighty Potomac,” Bowser said during a Feb. 20 situational update at the District’s Homeland Security and Emergency Management Agency in Congress Heights. “So for us, it has to be taken care of upriver, downriver, at the site, in D.C. It all has to be taken care of, and we are happy to be the conduit for the region.”
E. Coli Levels Rise as Ice Melts
Although the PI wastewater spill is considered one of the largest in U.S. history, with more than 240 million gallons of raw sewage entering the Potomac River, the region’s drinking water remains unaffected and safe to consume.
“The river is the source of our water, and we do get water…from the river, but it was upstream of this event, and it enters a system that is separated out from the sewage system,” said DC Health Director Dr. Ayanna Bennett on Feb. 20. “So the sewage water goes to the Blue Plains. The drinking water goes to the Washington Aqueduct, and they are not together.”
In her remarks, Bennett alluded to the testing of upstream water, telling reporters that the data showed no increase in pathogen levels, whereas the water that went downstream showed quite the opposite. Even so, Bennett expressed no cause for concern.
“The intake site that is downstream is the Little Falls,” Bennett said, “and that is closed during this season of the year generally and was not open at the time of the break and will not be opened anytime soon, as is routine. And so we don’t have any reason to think there’ll be contact between this sewage spill and our water intake at any point.”
More than eight miles away, at the headquarters of the Potomac Riverkeeper Network (PRKN), Betsy Nicholas has a slightly different take.
“We would have been in a completely different…situation if this had been just a tiny bit upstream of those pipes,” Nicholas, PRKN president, told The Informer. “Thank goodness that didn’t happen, but it’s also kind of an alarm going off– that we need to really pay a lot more attention to our risks with having a gigantic sewage line like that right next to the river.”
Since the Jan. 19 PI collapse, PRKN has collaborated with DC Water and the University of Maryland School of Public Health on consistent sampling of contaminated water. A report showed that, in the days following the collapse, levels of E. coli in the Potomac River were 12,000 times what was deemed safe for boating, fishing, and swimming.
Though subsequent water testing has shown some improvement, the most recent data highlights worsening pollution tied to melting ice and snow that has unleashed contaminants into the Potomac River.
Per local standards, E.coli concentration beyond the threshold of 410 most probable number (MPN) makes a body of water unsafe for recreation. However, samples collected on Feb. 12 from Lockhouse 10 on the C&O Canal show E.coli concentration at 54,000 MPN.
By Feb. 17, that amount increased to 80,900 MPN.
As Nicholas explained, levels will fluctuate as the weather changes.
“There’s still sewage all over the ground and at the bottom of the river,” Nicholas said, “which was in some ways worsened by the ice, because it just wasn’t flowing. So the solids dropped out, and they’re going to be on the river bottom for a while.”
All Hands on Deck
Since the approval of Bowser’s federal emergency assistance request, the U.S. Army Corps of Engineers (USACE) has been at the collapse and contamination sites, operating under the guidance of the National Response Framework, specifically as it relates to technical assistance, engineering expertise and construction management during disasters.
In collaboration with DC Water, USACE provides safeguards for the Potomac Interceptor repair operation and assists in the execution of an efficient response. To prevent the compromise of repair equipment and sewage overflow caused by heavy runoff, the engineering corps has been working to divert water away from the bypass pumping site.
“We’ve built a series of pulling and pumping locations where we’re collecting all that water using the existing drainage system,” USACE Baltimore District Commander Colonel Francisco Pena said on Feb. 23.
Pena, who’s leading USACE’s efforts on the ground, said this process entails the creation of ponds. Diversions created via a pumping system move the caught water from the ponds, past the repair site and into the Potomac River.
“So this is now water that’s normal stormwater runoff, a clean runoff,” Pena said, “but for the most part, we’re just pumping it right back into the Potomac. It’s not touching any other of the contaminated areas.”
Beyond its work with USACE on stormwater runoff mitigation, DC Water is excavating the 30-foot rock dam blocking the PI pipe, and preparing it for assessments and repair. Crews have gone into the damaged section and have almost completely cleared the site.
After officials determined that the pipe was too compromised for manual removal of rock debris, they employed alternative evacuation methods. As DC Water spokesperson Sherri Lewis explained on Feb. 23, trench boxes that have been installed provide stability while doubling the size of the excavated area and connecting the collapse site with a downstream access point to the Potomac Interceptor.
“Once we excavate down to that pipe section where the rock dam is located,” Lewis said, “we will cut into the crown of the pipe so that we can access that rock dam and remove those rocks that way, and that will help facilitate our repair process.”
As of Feb. 20, repairs and remediation has amounted to nearly $20 million. DC Water officials said an intermunicipal agreement will guide the split on the costs, so it won’t all fall on the District. Amid the discovery of a 2024 report assessing the condition of the PI, DC Water is conducting an internal investigation into what caused the collapse.
In the meantime, as multiple parties, local and federal, work to safeguard the Potomac River, the surrounding environment and the region’s water infrastructure, a mid-March PI full flow timeline increasingly appears likely.
For Nicholas, a positive outcome will be a milestone for the entire region to share.
“[There’s] a lot of pointing fingers politically as to who is responsible,” Nicholas told The Informer. “Hopefully this puts an end to that, and we can get everyone working on the same page about fixing this, investigating and trying to prevent it.”