Court Annuls New York’s Wetlands Regulations For Failure To Comply With SEQRA

The litigation will likely develop further in the coming days. The NYS Department of Environmental Conservation (“DEC”) has 30 days from the April 10, 2026 notice of entry filed by the Petitioners to appeal the decision. Typically, parties seeking an appeal file as quickly as possible, but DEC could exercise its right to use more of the time allotted.

The practical implication of the Court’s ruling is that the new Part 664 has been annulled and, by operation of law, the status quo before the invalid rule took effect controls. However, DEC retains its expanded wetlands authority under the 2022 Freshwater Wetlands Act. That authority took effect on the same day as the now annulled regulations implementing that authority.

The annulment of the regulations has created a situation previously avoided through the simultaneous effective date of the statutory amendments and the new regulations—DEC has expanded authority, but no regulations to guide and clarify specific implementation details.

Understanding The Decision

Petitioners challenging the Part 664 regulations included local governments, trade groups, nonprofits, business interests, and landowners. In the four cases consolidated in this decision, Petitioners raised a range of claims, including but not limited to claims that the rules are unconstitutionally vague, arbitrary and capricious, and infringe on Home Rule principles. The Court rejected all but the Petitioners’ SEQRA claims. In doing so, the Court denied Petitioners’ challenges to the 2022 legislative amendments to the Freshwater Wetlands Act, leaving the underlying statutory framework undisturbed.

The Court ruled for the Petitioners on their SEQRA claims in three of the four cases. The Court found that one individual petitioner, Mary Hutchings, had standing based on alleged environmental injuries to her use and enjoyment of Chautauqua Lake; three businesses and a municipality had standing based on their ownership of land impacted by the regulations; and the organizational petitioners in the case brought by the Business Council could proceed on an associational standing theory. The fourth case did not involve SEQRA claims and was denied.

The Court declined to resolve whether DEC properly classified the Part 664 regulations as an Unlisted action under SEQRA, or whether it should have instead classified the regulations as a Type I action. Even assuming that DEC properly treated the rulemaking as an Unlisted action, which is subject to more flexible review requirements than Type I actions, the Court found the SEQRA review deficient. In the Court’s view, DEC did not adequately identify relevant areas of environmental concern, did not take the required hard look, and did not provide a reasoned elaboration for its negative declaration. DEC’s explanation did not address potential adverse impacts or engage with concerns raised in public comments, nor did it explain how regulations affecting millions of acres could have no potential for significant adverse environmental impacts. The Court therefore annulled Part 664 in its entirety as noncompliant with SEQRA.

Because the Court annulled Part 664 on SEQRA grounds, it expressly stated that it did not need to reach Petitioners’ other challenges to the regulations. As a result, Petitioners’ other claims directed at Part 664, including claims that the regulations violate State Administrative Procedure Act and are arbitrary and capricious, were not addressed on the merits. Those challenges could reappear if DEC later seeks to re-promulgate Part 664 after additional SEQRA review.

Possible Next Steps In The Case

There are a few potential paths forward from here. It is unlikely that DEC will take no action due to its current lack of enforceable regulations, as discussed in more detail below.

• DEC could appeal and obtain a stay without court order.
  • If DEC seeks appellate review, it would automatically receive a stay under CPLR Section 5519(a)(1). While non-government movants must convince the Court that imminent harm, a likelihood of success on the merits, and the balance of the equities warrant the grant of a stay, CPLR Section 5519(a)(1) allows the government to skip over this test. If DEC moves for appeal and so automatically obtains a stay, the new regulations could return to being in effect relatively soon — on the order of weeks rather than months or years. The stay of the annulment would likely remain in effect through the resolution of the appeal.
  • As a general matter, regulations are struck down with some regularity, and appellate courts routinely stay such decisions to preserve the status quo while the appeal is heard.
• DEC could forgo an appeal and begin a SEQRA review process for the Part 664 regulations.
  • DEC encountered a similar issue in the context of its threatened and endangered species regulations at 6 NYCRR Part 182. In 2011, challengers sued DEC for failing to hold a public hearing in relation to Part 182 amendments. After years of appeals and settlement negotiations, DEC ultimately lost the case in 2022. The court declared that “the 2010 amendments to 6 NYCRR Part 182 were . . . declared null and void and [DEC was] enjoined from enforcing them.” In 2024, DEC initiated a new rulemaking to reinstate the regulatory language the court vacated. DEC reissued the entirety of the regulations as they existed prior to the 2022 court decision and provided a public comment period and public hearing to restore the regulations to their previous form. DEC stated that an alternative to the proposed action was to revert to the pre-2010 rules.
  • Considering Part 182 provides a window into what DEC might do next here. It is possible DEC will seek to complete SEQRA review and resubmit the same regulations that the Court just annulled, with minor changes, rather than seeking to appeal. This approach would have the benefit of reducing regulatory uncertainty as to how DEC may implement its expanded jurisdiction under the amended Freshwater Wetlands Act.
• DEC could appeal and ultimately win.
  • If DEC ultimately prevails on appeal, the new Part 664 regulations could be restored.
• DEC could appeal and ultimately lose.
  • If DEC ultimately loses, the regulations will remain annulled. DEC could complete a satisfactory SEQRA review to support the promulgation of the same or substantially similar regulations; however, that process could ultimately result in changes to the regulations and could take years to complete.

DEC Has Expanded Statutory Authority, But No Regulations, Pending Developments in the Litigation

The Court’s ruling does not touch the other aspects of DEC’s Part 664 rulemaking, nor does it clarify which rules, if any, now control. Rather, judicial vacatur of agency regulation “restores the status quo before the invalid rule took effect.” Envtl. Def. v. Leavitt, 329 F. Supp. 2d 55, 64 (D.D.C. 2004). To “confront the problem anew,” an agency must “initiate another rulemaking.” Independent U.S. Tanker Owners Committee v. Dole, 809 F.2d 847, 854-855 (D.C. Cir. 1987). As such, the new Part 664 is null and void, and DEC retains its expanded authority under Article 24, but lacks specific implementing regulations, leaving uncertainty with respect to how or whether DEC will in fact enforce and implement its authority. Further, the repeal of Part 662 and the addition of Appendix 56, which were also promulgated in DEC’s Part 664 rulemaking, are unaffected by the Court’s decision.

For the regulated community, this means that there is a return to uncertainty about the standards DEC will apply when determining and classifying jurisdictional wetlands and assessing compliance with wetlands permitting requirements.

Impacts on ORES Permitting Proceedings

For projects seeking Article VIII permits from the Office of Renewable Energy Siting and Electric Transmission’s (“ORES”), Article 24 is preempted by Article VIII, with ORES applying its own substantive standards through its regulations at 16 NYCRR Part 1100. That is, major renewable energy facilities need not obtain both a siting permit from ORES and a separate permit pursuant to Article 24; a final siting permit includes any wetlands mitigation requirements. Thus, while the new Part 664 is currently void, ORES’s regulations are unaffected, despite their reference in 16 NYCRR Section 1100-2.14 to the classification of wetlands as determined under 6 NYCRR Part 664. In the event that DEC’s new Part 664 regulations remain void, ORES may face increased complexity in its interpretation and application of the law. In the event the annulment is stayed by operation of law should DEC appeal, we expect ORES would continue to apply Part 664 as it has been since the regulation became effective.

Although the new Part 664 could potentially be resurrected through the pathways discussed above, until DEC determines its response to the Court’s decision, we expect that DEC will continue to enforce Article 24 and ORES will continue to apply its new regulations to applicable projects. For the time being, DEC’s 2025 wetlands regulations at Part 664 are void on SEQRA grounds, the 2022 statutory expansion of New York wetlands jurisdiction remains on the books, and DEC lacks specific implementing regulations. Until DEC indicates how it will respond to the decision, some uncertainty remains for regulated parties as to how Article 24 will be applied.

Foley Hoag is closely monitoring the litigation and developments in New York’s wetlands permitting regime. Watch this space for further updates.

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