A political dispute has emerged between President Donald Trump and Maryland Governor Wes Moore over responsibility for responding to a massive sewage spill that has contaminated the Potomac River and drawn federal intervention.

The incident began on January 19 when a section of the Potomac Interceptor, a 72-inch sewer pipeline owned and operated by DC Water, collapsed near the Clara Barton Parkway in Montgomery County, Maryland, releasing hundreds of millions of gallons of untreated wastewater into the Potomac River.

The spill, described by officials as among the largest in U.S. history, has prompted widespread environmental and public health concerns, including elevated bacteria levels and advisories against recreational contact with the water.

President Trump took to his social media platform to accuse Democratic leaders of “gross mismanagement” and specifically criticised Governor Moore’s handling of the situation, asserting that state and local authorities had failed to request timely federal assistance.

Trump announced that the Federal Emergency Management Agency would play a central role in coordinating the federal response despite a partial government funding impasse.

Moore’s office strongly rejected the president’s characterisation, noting that the Potomac Interceptor falls under the jurisdiction of DC Water and the U.S. Environmental Protection Agency, and asserting that Trump’s claims about Maryland’s role were incorrect.

A spokesperson for Moore called out the federal administration for failing to act sooner and highlighted that EPA officials did not participate in a recent legislative hearing on the cleanup.

In addition to the dispute over oversight, officials from DC Water have described the technical complexity of addressing the damage, with crews installing bypass systems and planning repairs that could take weeks or even months.

Environmental monitoring continues, with authorities issuing advisories for residents and visitors to avoid fishing, boating or other contact with affected stretches of the Potomac.

Maryland officials have also closed shellfish harvesting areas downstream to protect public health.

The exchange between Trump and Moore occurs amid broader tensions between federal and state leadership, including disagreements over infrastructure and public safety policies.

Maryland leaders have called for enhanced monitoring and oversight in response to what they describe as an ecological disaster with long-term implications for the river and the Chesapeake Bay ecosystem.

While drinking water systems drawing upstream are currently not believed to be affected by contamination, health officials emphasise ongoing testing and caution, especially as warmer weather approaches and recreational use of the river increases.

The dispute over responsibility underscores the challenges of coordinating multi-jurisdictional responses to large-scale environmental emergencies and the political pressures that follow such events.