New York environmental regulators filed a formal opposition against an effort by Williams Cos. to revive the long-canceled Constitution Pipeline, a project intended to transport natural gas from Pennsylvania into New York.

The New York State Department of Environmental Conservation (DEC) submitted a filing to the Federal Energy Regulatory Commission (FERC) protesting Constitution’s recent petition to reissue a Certificate of Public Convenience and Necessity. 

The DEC argues that reissuing the permit would effectively strip the state of its oversight authority under the federal Clean Water Act.

The proposed 124-mile pipeline—which includes 99 miles of construction within New York—was officially canceled by Williams in 2020 following years of legal and regulatory battles. However, the energy company is now seeking to reinstate the project's federal standing.

"Constitution is attempting to bypass critical environmental reviews and undercut New York State’s regulatory authority," the DEC stated in its filing. 

The agency emphasized that it never waived its authority under Section 401 of the Clean Water Act and pledged to "explore all available options to vigorously defend the state’s rights."

The dispute follows a complex political backdrop. In May, the Trump administration leveraged the state’s reconsideration of Williams’ pipeline projects as part of a deal with Governor Kathy Hochul. 

That agreement led to the lifting of a federal ban on Equinor’s Empire Wind offshore wind farm, currently under development off the New York coast.

While Hochul has not explicitly approved the gas pipelines, she previously stated the state would collaborate on projects that satisfy New York’s strict legal and environmental requirements. 

In a separate development, the DEC approved a water permit for another Williams project, the Northeast Supply Enhancement (NESE), this past November.

Officials at Williams Cos. were not immediately available for comment regarding the filing. The original Constitution project faced fierce opposition from environmental groups who argued the infrastructure would lock the region into decades of fossil fuel reliance.