The New York State Department of Environmental Conservation (DEC) has released guidance clarifying its implementation of Article 24 of the Environmental Conservation Law, known as the Freshwater Wetlands Act (FWA), following the Albany County Supreme Court’s annulment of DEC’s 6 NYCRR Part 664 regulations.

On April 8, 2026, Judge Richard M. Platkin of the New York State Supreme Court, Albany County, entirely annulled DEC’s revised Part 664 freshwater wetlands regulations for non-compliance with SEQRA. The underlying 2022 statutory amendments to the FWA, however, were left fully intact. This decision created uncertainty for the regulated community because the 2022 amendments had already replaced the prior map-based jurisdictional framework with a broader, definition-based approach to identifying regulated wetlands. As a result, it was unclear how DEC would implement the amended statute while new regulations were pending.

Continued Jurisdiction

In its Standard Operating Procedures, DEC indicated that the Part 664 regulations in effect prior to January 1, 2025, are now guiding staff’s implementation of the FWA, but only to the extent that the prior regulations do not conflict with the FWA as amended in 2022. In the event of inconsistency, the statutory amendments prevail. DEC confirmed that it will continue to accept and process Jurisdictional Determination (JD) requests, since the agency retains authority to administer the FWA.

Consistent with that approach, DEC stated that it will assert state jurisdiction over freshwater wetlands that are:

• documented on pre-2025 state regulatory maps (identified as “Previously Mapped Freshwater Wetlands” on DEC’s Environmental Resource Mapper)
• 12.4 acres or larger, regardless of whether included as Previously Mapped Freshwater Wetlands; including wetlands meeting the acreage threshold through hydrologic connections

Previously Mapped Wetlands remain jurisdictional because they were validly designated under the prior mapping regime. Although the 2022 statutory amendments eliminated the requirement that wetlands be mapped as a prerequisite for future jurisdiction, they did not invalidate existing mapped wetlands or prior JDs. The 12.4-acre rule remains fully enforceable since it is expressly set forth in the statute and does not depend on the annulled regulations.

During DEC’s June informational webinar, the agency strongly emphasized that wetlands that appear smaller than 12.4 acres may still warrant a JD, since the wetland may be part of a larger hydrologically connected wetland system that reaches the threshold. JDs are primarily conducted through a GIS-based remote review process, in addition to DEC staff evaluation of multiple spatial datasets, including Previously Mapped Wetlands, National Wetlands Inventory data, soils information, aerial imagery, and elevation data.

Responsible parties are strongly encouraged to seek JDs whenever uncertainty exists, particularly for parcels located near Previously Mapped Freshwater Wetlands. JDs will remain the principal mechanism for resolving site-specific jurisdictional questions while new regulations are developed.

Positive Jurisdictional Determinations Referencing “Unusual Importance” Criteria

The revised Part 664 regulations provided detailed criteria for applying the eleven “Unusual Importance” categories established in the 2022 amendments to the FWA. With those regulations annulled, there is no longer a legal framework for implementing these categories, and JDs that relied solely on the “Unusual Importance” criteria may now have no valid legal basis. DEC has indicated that it is not currently asserting jurisdiction based solely on those categories while new regulations are developed. Requestors who received a positive JD between January 1, 2025, and April 8, 2026, and whose jurisdiction letter references “Unusual Importance” criteria without mentioning Previously Mapped Wetlands, will need additional review. Recipients of these positive JDs should complete the online Reassessment of Jurisdictional Determination Request to ensure compliance with the updated regulations. In conducting additional review, DEC will assess whether jurisdiction can be supported under the current interim framework.

Anticipated Impacts

Landowners, developers, and other regulated parties should expect more fact‑intensive review of JDs and permit applications and potentially longer timelines as DEC applies the statute without a complete regulatory framework. Because DEC is using GIS-based review to evaluate hydrologic connections and determine whether unmapped wetlands exceed the statutory acreage threshold, applicants should rely on JDs to obtain certainty regarding regulatory status before disturbing potentially regulated wetlands.