“Trickling-In”: Second Circuit Refines the 401 Water Quality Certification Scope and Procedures

For years, courts have incrementally expanded the scope and nature of restrictions on developments at or near waters of the United States (WOTUS), including wetlands, using a state’s authority to issue deny, or approve with conditions the required 401 water quality certification (401 WQC). It appears the pendulum may be swinging the other way.  

Most projects impacting WOTUS require the affected state to issue 401 WQC before it may proceed. In Raritan Baykeeper, Inc., et al. v. New York State Department of Environmental Conservation (DEC), et al., 2026 WL 2453538 (August 21, 2026), the United States Court of Appeals for the Second Circuit rejected environmentalists' petition for review and set new boundaries for challenges to a state-issued 401 WQC. Petitioners sought to reverse the 2025 grant of 401 WQC for planned placement of the Transcontinental Gas Pipeline Company's (Transco) proposed Northeast Supply Enhancement (NESE) pipeline underwater in Raritan Bay and Lower New York Bay to approximately three miles offshore of Queens. Ultimately, the Court found the New York decision did not violate the Clean Water Act (CWA), was not arbitrary and capricious or otherwise contrary to law and did not violate the notice and comment principles or state procedural requirements.

The Court rejected “petitioners' argument that NYSDEC was required to provide a more substantial justification [for the pipeline project because it had previously denied 401 WQC]. An agency is not required to give more reasoning than is otherwise required [by Clean Water Act].” Id. At *5 [Emphasis added]. Accordingly, procedural deficiencies resulting in a 401 WQC denial should not deter applicants. 

The 2nd Circuit also rejected petitioners' claim that the State that issued the 401 WQC was not permitted to rely on a post-certification compliance plan in granting the water quality certification. The Court did not agree: "WQC is based on NYSDEC's extensive technical review of Transco's application and the agency's determination that the NESE project will comply with New York water quality standards if certain conditions are met, including continuous water quality monitoring, specific construction windows and employment of an independent third-party monitor with stop-work authority [after issuance of the 401 WQC].” The 401 WQC requires Transco to comply with specific water quality standards as to roughly a dozen pollutants for each segment of the proposed pipeline, based on best usages and anticipated environmental conditions of each segment. The Court found post-certification compliance plans do not constitute a deferral of the agency's obligation to ensure the project would meet water quality standards. “Rather, the agency discharged that obligation by incorporating additional protections into the WQC.”

Lastly, the Court rejected the argument that additional public participation was required for review and comment of the 401 WQC compliance plans. "But a general policy favoring public participation cannot be read to impose public notice and comment requirements over and above those already contained in federal and state law, which mandate public notice and comment only on complete § 401 'applications,'" the order opinion said.