6 Things You Need to Know About the New NYSDEC Freshwater Wetlands Regulations
Tiffany Toukatly, Wetland Biologist
Tiffany Toukatly, Wetland Biologist
Historically, NYSDEC freshwater wetland jurisdiction was based on official mapped wetlands. Under the updated regulations, those maps are now informational only, and are not regulated. Now, wetlands may be regulated if they meet the statutory definition and jurisdictional criteria– even if they are not shown on existing DEC maps.
Why this matters: Sites previously assumed to be unregulated may now require state review and permitting. Working with an experienced wetland consulting team early can help identify potential constraints before they become costly surprises.
The revised regulations allow NYSDEC to regulate wetlands of any size if they are determined to be of unusual importance. These may include wetlands that:
Why this matters: Small wetlands are no longer automatically exempt from state regulation. A qualified environmental consulting firm can assess whether your site includes features that may trigger jurisdiction.
Because regulation is no longer map-based, NYSDEC now relies on Jurisdictional Determinations (JDs) to confirm whether wetlands and adjacent areas on a parcel are subject to state regulation. A JD provides regulatory clarity and is typically valid for five years once issued.
Why this matters: A JD needs to be requested early in the planning process to avoid permitting delays or redesign later in the project. Experienced wetland consulting professionals can prepare and submit JD requests on your behalf.
As of January 1, 2025, freshwater wetlands 12.4 acres or larger are regulated statewide, along with wetlands of unusual importance.
Beginning January 1, 2028, the default size threshold will decrease to 7.4 acres, expanding state jurisdiction even further.
Why this matters: Long-term or phased projects should account for this future regulatory change. Proactive environmental consulting can help you plan around evolving requirements.
NYSDEC has included a transition period for projects that were already under review prior to January 1, 2025. Projects with accepted permit applications, issued approvals, or formal agency determinations may, in some cases, proceed under the previous freshwater wetlands regulatory framework, depending on project status and DEC coordination.
Projects initiating review after January 1, 2025 are generally subject to the new regulations, including updated jurisdictional determination and permitting requirements.
Why this matters: Project timing, documentation, and early agency coordination can significantly affect permitting scope, schedule, and cost. Eligibility for the transition period is evaluated case-by-case.
The wetland regulatory expansion now brings many more wetlands into jurisdiction under NYSDEC review (an estimated 1 million additional acres).
To help manage this NYSDEC has issued and proposed general permits that authorize common activities (e.g., minor construction or maintenance) under standardized conditions. Some projects may be permitted under a general permit instead of going through lengthy individual reviews — but only if eligibility criteria are met. These general permits allow for a shorter and more streamlined review by NYSDEC.
Why this matters: By assessing a project’s impacts on state wetlands and/or the 100-foot wetland adjacent area early in the planning process, your environmental consulting partner can determine whether the project qualifies for a general permit and a faster approval timeline.
✔ Early wetland delineation and JD requests are more important than ever.
✔ Can not rely solely on historic wetland maps anymore.
✔ Small or previously unregulated wetlands may now require permits.
✔ Early coordination with a wetland consulting firm can preserve regulatory certainty and reduce risk
Costich Engineering’s Environmental Services team provides comprehensive environmental consulting and wetland consulting services to help clients navigate the updated NYSDEC freshwater wetlands regulations with clarity and efficiency. We support projects from early planning through permitting by identifying wetland constraints, confirming state jurisdiction, and coordinating directly with regulatory agencies to reduce risk and avoid delays.
Our services include:
By addressing wetland considerations early, Costich helps protect project schedules, budgets, and long-term feasibility.
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