New York court voids state wetland rules; agency narrows which unmapped wetlands need permits

On April 8, 2026, the Supreme Court, Albany County (Platkin, J.), annulled in their entirety the freshwater wetlands regulations of the New York State Department of Environmental Conservation ("DEC"), 6 NYCRR Part 664, in Chautauqua Lake Property Owners Assn., Inc. v. State of New York, 2026 NY Slip Op 26053 (Index No. 903982-25). The court held that DEC had not complied with the State Environmental Quality Review Act ("SEQRA") when it adopted the rules, which took effect January 1, 2025. The decision leaves standing the 2022 amendments to the Freshwater Wetlands Act, ECL Article 24, which the court upheld against facial constitutional challenge, but it removes the regulatory framework DEC had built to apply them.

The State did not appeal by the May 11, 2026 deadline. Several petitioners, led by the Chautauqua Lake Property Owners Association, filed a notice of appeal to the Appellate Division, Third Department in May 2026, seeking a ruling that the 2022 amendments themselves are unconstitutional. For anyone diligencing land in New York, the question of which wetlands are State-regulated now has a different answer than it did in 2025, and it may change again.

The statute and the annulled rules

ECL § 24-0107 defines "freshwater wetlands" as lands and waters of at least 12.4 acres or, if smaller, of "unusual importance," and lowers the acreage threshold to 7.4 acres on January 1, 2028. The statutory list of unusual-importance characteristics includes wetlands in urban areas, wetlands supporting rare or endangered species, vernal pools productive for amphibian breeding, and wetlands in FEMA-designated floodways. As the court put it, following the 2022 amendments "DEC's wetland maps are merely informational and not necessarily determinative of regulatory jurisdiction."

Part 664 supplied the classification system and procedures through which DEC applied those definitions. In annulling it, the court found that DEC "failed to identify the relevant areas of environmental concern, did not take a 'hard look' at them and did not make a reasoned elaboration" for its negative declaration under SEQRA. The court rejected the petitioners' due process, vagueness, delegation and home rule challenges.

DEC's interim position

DEC's freshwater wetlands program page now states that permits are required for projects impacting "Previously Mapped Freshwater Wetlands and/or wetlands of 12.4 acres or greater in size." Interim guidance issued after the decision, as summarized in published practitioner alerts, confirms that DEC continues to regulate the 100-foot adjacent area around jurisdictional wetlands and, apart from wetlands DEC mapped before 2025, is not currently asserting jurisdiction based solely on the statute's unusual-importance categories. Positive jurisdictional determinations issued between January 1, 2025 and April 8, 2026 that rest only on those categories are subject to reassessment.

The most consequential change for day-to-day practice is that a wetland smaller than 12.4 acres that DEC never mapped is, for now, outside DEC's asserted jurisdiction unless it qualifies on another basis. That position rests on agency guidance, not on a promulgated rule. The unusual-importance criteria remain in the statute, and a renewed rulemaking supported by fuller SEQRA review, or an appellate ruling, could restore their practical effect. The 7.4-acre threshold takes effect by statute on January 1, 2028 whatever happens to the regulations.

Jurisdictional determinations

ECL § 24-0703(5) allows any person to ask DEC whether a parcel contains a freshwater wetland and requires a written answer within 90 days, which DEC may extend where weather or ground conditions prevent a determination. A negative answer is "a complete defense to the enforcement of this article as to such parcel of land for a period of five years"; an affirmative answer remains reviewable. The five-year protection therefore attaches to a negative determination, and it is the only form of certainty the statute offers while the regulatory position is in flux.

Practical effects

Owners and buyers of parcels with smaller, unmapped wetlands, applicants with pending freshwater wetlands permit applications, and holders of positive determinations issued during the fifteen months Part 664 was in force are the most directly affected. Projects that were redesigned or delayed in 2025 to avoid an unusual-importance wetland may now have room to revisit that design, subject to the risk that the position changes again before construction.

The transactional consequences deserve attention. Purchase and sale agreements, option agreements and loan commitments negotiated in 2025 may contain wetlands contingencies, price adjustments, extended diligence periods or permit-based closing conditions drafted on the assumption that Part 664 applied. Those terms may now be over- or under-inclusive. Environmental representations are better drafted to address both DEC mapping and the statutory definition, with an express allocation of the risk that jurisdiction expands after closing through the appeal, a new rule or the 2028 threshold.

What to do now

Holders of positive determinations issued between January 1, 2025 and April 8, 2026 that rely solely on unusual-importance criteria should consider requesting reassessment. Owners intending to hold or develop a parcel over several years should weigh the value of a negative determination and its five-year defense. Projects that will not be permitted or built before January 1, 2028 should be planned against the 7.4-acre threshold now. The prudent course is to treat the current position as interim, follow the Third Department appeal and any DEC rulemaking, and avoid deal terms that depend on the present guidance remaining in place.