Two contractors injured in explosion at Patapsco wastewater plant

Two contractors were injured Tuesday afternoon in an explosion at Baltimore’s Patapsco Wastewater Treatment Plant in far South Baltimore, renewing scrutiny of a city facility that has been under state review for years. First responders were called shortly after 1 p.m. to the 3500 block of Asiatic Avenue, and both workers were taken to a hospital. Their conditions were not immediately known.

Stancil McNair, of AFSCME Local 44, said the injured men were contractors, not city employees. McNair said he had heard they may have touched something that triggered the blast, and he described burns so severe that their gloves had stuck to their hands. The Baltimore City Department of Public Works, which operates the plant, said it would comment after getting more information, and the Maryland Department of Energy was also contacted.

The explosion landed at a plant with a long compliance record and a stated treatment capacity of 73 million gallons a day. Maryland Department of the Environment documents describe Patapsco as an activated sludge wastewater treatment plant that uses ferric chloride for phosphorus removal, and its compliance page includes inspection reports and permit-related actions from 2021, 2022, 2023 and 2024. A May 18, 2022 inspection required the plant to submit a PCB minimization plan within 60 days, underscoring how closely regulators have been watching its operations.

That history matters because a 2022 state inspection had already flagged the risk of fire and explosion at Patapsco, citing dangerous chemical buildup in backed-up sewage sludge. The plant is part of Baltimore’s wastewater system, which has been covered by a consent decree for years as the city has faced repeated questions about safety, environmental compliance and whether long-running fixes are being completed fast enough. Public Works has said it has spent more than $250 million on wastewater plant investments, including Patapsco and the Back River Wastewater Treatment Plant, but community and environmental advocates have continued to raise alarms about solids-processing problems and staffing and training gaps.

The latest blast also arrives as Patapsco remains a key pressure point in the region’s sewer system. Baltimore Brew reported in March 2026 that the plant was effectively maxed out and could not accept additional county sewage, a constraint that helped trigger a development cut-off in northwestern Anne Arundel County. With the plant already under scrutiny and Baltimore’s other major wastewater facility still carrying its own history of explosions and contamination problems, the injuries on Asiatic Avenue are likely to intensify demands for answers on what failed, what inspections follow, and whether the city’s capital work has kept pace with the risks already identified.