Freshwater Wetlands Program

Freshwater Wetlands Program

In 1975, New York State Legislature passed The Freshwater Wetlands Act (Environmental Conservation Law Article 24) to preserve, protect, and conserve freshwater wetlands and their benefits, consistent with the general welfare and beneficial economic, social and agricultural development of the state. 

Wetlands are essential for maintaining biodiversity, mitigating flooding, and protecting water quality. DEC’s Freshwater Wetland Protection Program ensures that wetlands are appropriately classified and regulated to support ecological functions and maintain community resilience.

For a wetland to be eligible for protection under the Freshwater Wetlands Act, it must meet one of the following criteria:

• It must be 12.4 acres (5 hectares) in size or greater. As of January 1, 2028, the threshold will decrease to 7.4 acres (3 hectares). Two or more wetlands may be considered a single wetland if they are hydrologically connected and separated by no more than 50 meters.
• It is a Previously Mapped Freshwater Wetland, mapped by the department before January 1, 2025. 
• It was mapped by the department as a wetland of Unusual Local Importance before January 1, 2025
• To ensure the functions and benefits of jurisdictional wetlands are preserved, a 100-foot adjacent area is protected to maintain protective buffers.

Wetland Classification

Different types of wetlands provide different functions and benefits. The Act requires wetlands to be ranked based on the benefits and values provided. This system establishes four classes that rank wetlands according to their ability to perform wetland functions and provide wetland benefits. Wetlands are ranked Class I as the highest level of protections through Class IV as the lowest level of protections. It often is more difficult to get a permit to alter a Class I wetland than a Class II or III wetland because Class I wetlands provide more important wetland benefits.  Lower ranked wetlands still provide important functions and benefits but typically require less protection to continue to provide these functions.

The federal Clean Water Act regulates activities in a similar manner but has slightly different requirements. Landowners are encouraged to contact the U.S. Army Corps of Engineers if they anticipate undertaking activities in or near wet areas.

Wetland Maps

DEC’s Environmental Resource Mapper (ERM) is a helpful tool to identify jurisdictional and potential jurisdictional wetlands. 

Environmental Resource Mapper (ERM)

Previously Mapped Freshwater Wetlands can be viewed on the ERM and this layer confirms the presence of regulated wetlands and wetlands of unusual local importance. Additionally, on the ERM view the Freshwater Wetland Informational Maps and National Wetland Inventory maps to identify wetland continuity

Regulated Activities

Under the Freshwater Wetlands Act, DEC regulates activities in freshwater wetlands and in their adjacent areas. DEC regulates such activities to prevent, or at least to minimize, impairment of wetland functions.

The wetland categories used in the regulations are identified by the types of vegetation present. The regulations identify:

• classifications of uses;
• procedures for conducting activities in wetlands; and
• requirements for conducting activities in wetlands.

Almost any activity which may adversely impact the natural values of the wetlands or their adjacent areas is regulated. Some activities requiring a permit include:

• construction of buildings, roadways, septic systems, bulkheads, dikes, or dams;
• placement of fill, excavation, or grading;
• modification, expansion, or extensive restoration of existing structures;
• drainage, except for agriculture; and
• application of pesticides in wetlands.

A permit is required to conduct any regulated activity in a protected wetland or its adjacent area. The permit standards in the regulations require that impacts to wetlands be avoided and minimized. 

• If the proposed activity will not seriously affect the wetland, a permit with various conditions is usually issued.
• If the proposed activity will affect the wetland, the benefits gained by allowing the action to occur must outweigh the wetland benefits lost, in order for a permit to be issued.
• Compensatory mitigation often is required for significant impacts to wetlands. This may include creating or restoring wetlands to replace the benefits lost by the proposed project.

General Permits for Freshwater Wetlands

• DEC is proposing statewide general permits to ease permitting and streamline the approval of specific activities. General permits are only for activities that have been determined to have limited impact on the environment. They allow similar types of work not unique to a particular location, require less time to process and no application fees.
• Currently, there are five available general permits, Fresh Water Wetland Permit (GP-25-003) , Solar Photovoltaic Projects (Less than 25 MW) General Permit (GP-0-25-004), Electric Utility Right of Way Maintenance and Repair General Permit (GP-0-25-005), Natural Gas Utility Right of Way Maintenance and Repair General Permit (GP-0-25-009)  and Lakes and Shorelines General Permit (GP-0-25-007). Additionally, DEC has proposed four general permits to address regulated activities within jurisdictional wetlands and adjacent areas. 

Real Property Assessment

Real property valuation is assessed at the local level, not through DEC at the state level. The Freshwater Wetlands Act recognizes that land use may influence property valuation. For more information, visit the Real Property Assessment webpage.

Contacts for Freshwater Wetlands

DEC's Freshwater Wetlands Program resides in the Division of Fish and Wildlife. Most aspects of the wetlands program are implemented by staff in regional offices and can be reached at the below emails.