Court Backs New York Approval of $1B Williams Gas Pipeline

Energy Infrastructure Court Backs New York Approval of $1B Williams Gas Pipeline Ruling preserves water-quality permit for 37-mile Northeast Supply Enhancement project amid other legal challenges The U.S. Court of Appeals in New York City on Aug. 21 upheld New York's water-quality approval for developer Williams Cos.' more than $1-billion Northeast Supply Enhancement natural gas pipeline project, rejecting an environmental coalition's challenge to a key permit for the multistate line expansion into the city. The line would add roughly 37 miles of pipeline and related facilities from Pennsylvania through New Jersey to a terminus in Queens, increasing Williams subsidiary Transcontinental Gas Pipe Line Co.'s capacity by 400,000 dekatherms per day to serve National Grid customers in New York City and Long Island. Williams marked what it called the official start of construction at an April 14 groundbreaking and has targeted the fourth quarter of 2027 for the project to enter service. The court found the New York State Dept. of Environmental Conservation adequately explained why it approved the project in 2025 after rejecting a similar application in 2020. The ruling leaves intact the state's Clean Water Act Section 401 certification for the project's 17-mile crossing of New York Harbor. Work includes 10.1 miles of 42-in.-dia pipeline in Pennsylvania and 26-in.-dia pipeline segments in New Jersey and New York City, including about 23 miles offshore in Raritan Bay and in New York state waters. The project also includes a new 32,000-hp compressor station in Somerset County, N.J., and an additional electric motor-driven compressor at an existing station in Chester County, Pa. The opponent coalition, which includes NY/NJ Baykeeper, Sierra Club and the Natural Resources Defense Council, argued that the department had not adequately justified reversing its previous position and improperly relied on compliance plans to be finalized after the permit was issued. The appeals court disagreed, saying the agency "provided sufficient reasons" for granting the renewed application and that Transco had addressed concerns underlying the state's earlier rejection during the administration of Gov. Andrew Cuomo, who preceded current Gov. Kathy Hochul, both Democrats. New Technical Record Supported Approval The department's 2020 denial centered partly on construction impacts from disturbing Raritan Bay sediment contaminated with mercury and copper. It questioned use of a 500-ft mixing zone around construction in sensitive hard-clam habitat, Transco's estimate that jet trenching would result in 5% sediment loss and the developer's proposal to bury the pipeline 4 ft below the seabed rather than 6 ft. Looking for quick answers on construction and engineering topics? Try Ask ENR, our new smart AI search tool. Ask ENR → The Northeast Supply Enhancement project would extend Transco's existing system through New Jersey and across Raritan Bay and New York Harbor to the Rockaway Peninsula in Queens. Map: Williams Co./ENR In its renewed application, Transco corrected an earlier calculation that put hard-clam density along the route at 69.6 clams per sq ft, reducing it to 3.7 based on the same survey data. The developer also cited completed projects on which actual sediment loss proved far lower than earlier estimates and it provided additional analysis showing that deeper burial could increase sediment suspension. The department determined that 6-ft burial used for some offshore transmission projects addressed electromagnetic-field concerns that do not apply to a gas pipeline. The court also rejected the challengers' contention that the agency improperly deferred environmental safeguards until after certification. The permit establishes pollutant limits and construction windows, requires continuous water-quality monitoring and calls for an independent third-party monitor with stop-work authority. Several compliance plans require state approval before applicable construction begins, measures the court said provide the "necessary guardrails" to ensure compliance with water-quality standards. No additional department permits are required, although Transco must complete required compliance plans and satisfy conditions of its existing approvals before applicable work proceeds. The department told ENR it is "committed to closely monitoring" construction and adherence to all permit conditions "to ensure the full protection of New York's waterways." RELATED Controversial $1B Gas Pipeline Gains NJ-NY Approvals for Construction Pipeline Advances Amid Other Challenges The decision marks another turn for a project Williams stopped pursuing in 2020 after New York and New Jersey repeatedly denied required water-quality approvals. The Federal Energy Regulatory Commission reissued the project's federal construction certificate in August 2025, followed by new water-quality approvals from both states that November. Clean Ocean Action and other opponents of the Northeast Supply Enhancement project rally against the proposed pipeline, which continues to face separate legal challenges in federal courts in New Jersey and in Washington, D.C. Photo courtesy Clean Ocean Action Williams spokesperson Alex Schott called the ruling an "important step forward" for the pipeline. The company has not publicly detailed how much construction has occurred since the April groundbreaking. Local reporting in late July indicated Raritan Bay work had not started, while Williams continued to say the project was moving forward and targeted service by the end of 2027. Susan Kraham, an Earthjustice attorney representing several challengers, said the New York environmental regulator had been right to reject the pipeline previously because of water-quality concerns. "It should have done so again," she said following the ruling. Earthjustice spokesperson Nydia Gutiérrez told ENR that petitioners are "reviewing the decision" when asked whether they would seek rehearing or further review. She said challenges to New Jersey's Section 401 certification and FERC approval remain pending and could affect the project, and noted a separate state-court challenge to New Jersey's Tidelands Resource Council utility license. Those cases involve approvals separate from the New York permit. The federal appeals court in Philadelphia also is considering the challenge to New Jersey's Section 401 water-quality approval, while the Washington, D.C., appellate court is reviewing FERC reissuance of the project's federal construction certificate. The New Jersey Superior Court case challenges the license allowing Transco to use state-owned underwater lands for the Raritan Bay crossing.