ARTICLE 24, ENVIRONMENTAL CONSERVATION LAW
IMPLEMENTING REGULATIONS - 6NYCRR Part 663, Part 664, and Part 665
On this page:
- Determine if you need an application
- Application Procedures
- Major or Minor Project
- Standards of Issuance
Freshwater wetlands are lands and submerged lands, commonly called marshes, swamps, sloughs, bogs, and flats, supporting aquatic or semi-aquatic vegetation. These ecological areas are valuable resources, necessary for flood control, surface and ground water protection, wildlife habitat, open space, and water resources. Freshwater wetlands also provide opportunities for recreation, education and research, and aesthetic appreciation. Adjacent areas may share some of these values and in addition, provide a valuable buffer for the wetlands.
The Department has classified regulated freshwater wetlands according to their respective functions, values and benefits. Wetlands may be Class I, II, III or IV. Class I wetlands are the most valuable and are subject to the most stringent standards.
Certain human activities can adversely affect, even destroy the delicate ecological balance in these important areas. The policy of New York State; set forth in the Freshwater Wetlands Act, is to preserve and protect the benefits that wetlands provide.
The Department of Environmental Conservation was charged with implementing this policy through its Freshwater Wetlands Regulatory Program. Intended to prevent despoliation and destruction of freshwater wetlands, these regulations were designed to:
- preserve, protect, and enhance the present and potential values of wetlands;
- protect the public health and welfare; and
- be consistent with the reasonable economic and social development of the state.
*Note: Amendments were made in 2022 to the regulatory program. A summary of those changes (PDF) is available.
Article 24 of the Environmental Conservation Law, section 24-0105 (statement of findings) lists the benefits of freshwater wetlands that the Department is mandated to protect.
Freshwater wetlands provide:
- Flood and storm control by the hydrologic absorption and storage capacity
- wildlife habitat (breeding, nesting and feeding grounds and cover for wildlife, waterfowl, and shore birds including migratory waterfowl and rare species such as the bald eagle and osprey)
- protection of subsurface water resources and ground water recharge
- recreation
- hunting
- fishing
- boating
- hiking
- bird watching
- photography
- camping and other uses
- pollution treatment by serving as biological and chemical oxidation basins
- erosion control by serving as sedimentation areas, filtering basins,
- protection of channels and harbors by absorbing silt and organic matter
- education and scientific research by providing readily accessible outdoor bio-physical laboratories, living classrooms and vast training and education resources
- open space and aesthetic appreciation derived from the fact that they are often the only remaining open areas along crowded river fronts and coastal Great Lakes regions.
- sources of nutrients in freshwater food cycles and nursery grounds and sanctuaries for freshwater fish
Informational Freshwater Wetland Maps
As of January 1, 2025, DEC’s regulatory protections of freshwater wetlands are no longer limited to wetlands depicted on the NYS Freshwater Wetlands Maps and the NYS Freshwater Wetlands Maps are referred to as Previously Mapped Freshwater Wetlands. Jurisdictional protections for previously mapped freshwater wetlands remain and DEC’s jurisdictional authority over freshwater wetlands has expanded under recent amendments to the Freshwater Wetland Jurisdiction and Classification regulations (6 NYCRR Part 664).
To assist the public in identifying freshwater wetland areas that may be jurisdictional, DEC has produced non-regulatory, Informational Freshwater Wetland Maps. DEC Informational Freshwater Wetland Maps are available for download through the New York State GIS Clearinghouse and are also available for viewing through the Environmental Resource Mapper (ERM), a web based interactive mapping application. The Informational Freshwater Wetland Maps are for informational purposes only and cannot be relied upon to determine the presence or absence of freshwater wetlands regulated by DEC.
The only way to confirm the presence or absence of a freshwater wetland regulated by DEC is to receive a jurisdictional determination, as described further on the Freshwater Wetland Jurisdictional Determination webpage. These determinations will be made remotely based on wetland acreage and characteristics meeting jurisdictional criteria.