Pipeline Cleanup Completed, Environmental Concerns Remain on Potomac River Project

Cleanup efforts following sediment and iron runoff from natural gas pipeline construction into the Chesapeake and Ohio (C&O) Canal west of Hancock, Maryland, have been completed, according to TC Energy. Still, environmental monitoring continues, and a portion of Berm Road remains closed due to ongoing concerns about potential impacts to a local spring.

Cleanup and Environmental Violations

Columbia Gas, under a Special Use Permit from the National Park Service, finished the cleanup operate in mid-December 2025. The work addressed sediment and iron precipitate that entered the C&O Canal and adjacent floodplain following an inadvertent return of drilling fluids during horizontal directional drilling under the Potomac River. This incident affected a local spring along Berm Road.

An unannounced inspection by the Maryland Department of the Environment (MDE) on November 13, 2025, revealed environmental rule violations. The MDE inspection report indicated that the sediment and iron pollution, as well as disturbances to other areas, had not been authorized. The MDE subsequently recommended the removal of sediment and iron from the canal.

Pipeline Project Details

The project involves a 3.5-mile extension of a TC Energy natural gas pipeline running west of Hancock, Maryland. The pipeline is buried approximately 100 feet below the Potomac River and the C&O Canal towpath . The 8-inch diameter pipeline connects to an existing pipeline in Pennsylvania and is intended to supply gas to the Mountaineer Gas pipeline in West Virginia.

TC Energy, in partnership with Columbia Gas Transmission, is constructing the 3.4-mile natural gas extension, employing approximately 100 people at a capital cost of around $24.97 million . Horizontal directional drilling under the Potomac River spans .8 miles (4300 feet) and is expected to be completed by March 2026 .

Ongoing Monitoring and Road Closure

Berm Road remains closed to public traffic. TC Energy continues to monitor the local spring affected by the drilling fluid release and will not approve road restoration work until the effects have dissipated. The company states it has been coordinating with local residents to manage the road closure for several months.

TC Energy submits biweekly status reports to the Federal Energy Regulatory Commission (FERC) as part of its federal permit requirements . The company utilizes a full-time Environmental Inspector and drone technology for environmental monitoring .