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Freshwater Wetlands Program

Why Are Wetlands Valuable?

Wetlands are known by many names, such as marshes, swamps, bogs, and wet meadows. Wetlands are transition areas between uplands and aquatic habitats. Standing water is only one clue that a wetland may be present. Many wetlands only have visible water during certain seasons of the year. For many years, people did not recognize the many diverse benefits and values of wetlands. Consequently, New York has lost almost half of its historic wetlands to such activities as filling and draining. However, wetlands are valuable to the people and environment of New York State. Some of the functions and benefits that wetlands perform include:

Flood and Storm Water Control

Wetlands provide critical flood and stormwater control functions. They absorb, store, and slow down the movement of rain and melt water, minimizing flooding and stabilizing water flow.

Surface and Groundwater Protection

Wetlands often serve as groundwater discharge sites; maintaining base flow in streams and rivers; and supporting ponds and lakes. In some places, wetlands are very important in recharging groundwater supplies. Wetlands also improve water quality by absorbing pollutants and reducing turbidity.

Erosion Control

Wetlands slow water velocity and filter sediments, protecting streams, lakes, reservoirs and navigational channels. They also buffer shorelines and agricultural soils from water erosion.

Pollution Treatment and Nutrient Cycling

Wetlands cleanse water by filtering out natural and many manmade pollutants, which are then broken down or immobilized. In wetlands, organic materials are also broken down and recycled back into the environment, where they support the food chain.

Fish and Wildlife Habitat

Wetlands are one of the most productive habitats for feeding, nesting, spawning, resting and cover for fish and wildlife, including many rare and endangered species.

Public Enjoyment

Wetlands provide areas for recreation, education and research. They also provide valuable open space, especially in developing areas where they may be the only green space remaining.

Freshwater Wetlands Act

The State Legislature passed The Freshwater Wetlands Act (PDF) (129 kB)(Act) in 1975 with the intent 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.

The Act identifies wetlands on the basis of vegetation because certain types of plants out-comepete others when they are in wet soils, and so are good indicators of wet conditions over time. These characteristic plants include wetland trees and shrubs, such as willows and alders; emergent plants such as cattails and sedges; aquatic plants, such as water lily, and bog mat vegetation, such as sphagnum moss.

To be protected under the Freshwater Wetlands Act, a wetland must be 12.4 acres (5 hectares or larger). Wetlands smaller than this may be protected if they are considered of unusual local importance. Around every wetland is an 'adjacent area' of 100 feet that is also regulated to provide protection for the wetland.

Certain activities are exempt from regulation; other activities that could have negative impact on wetlands are regulated. The Regulated Activities webpage contains more examples of regulated activities and those exempt from wetland permits. 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.

The U.S. Army Corps of Engineers (ACOE) also protects wetlands, irrespective of size, under Section 404 of the Clean Water Act. Although the ACOE definition of wetland is slightly different than the state definition, the Clean Water Act protects basically the same thing -- areas of water or wet soils that support wetland plants.

Wetland Maps

The Act requires DEC to map all those wetlands regulated by the Act. Landowners who are within the regulated adjacent area (usually 100 ft) surrounding the wetland or whose properties include regulated wetland are notified of that fact. The maps also allow other interested parties to know where jurisdictional wetlands exist. DEC prepares draft maps, notifies landowners whose property may contain protected wetlands, and provides an opportunity for comment on the accuracy of the maps. DEC then reviews the comments received, adjusts the maps if necessary, and then officially files the final maps with the clerks of all local governments. Wetlands are a changing resource, and the law provides the opportunity for amending the maps. Any changes to the maps require affected landowners to be provided with notification and an opportunity for public comment.

However, the US Army Corps of Engineers (Corps) regulates most wetlands in New York State. There are no regulatory maps identifying wetlands regulated by the U.S. Army Corps of Engineers under the Clean Water Act. Wetlands shown on the DEC maps usually are also regulated by the Corps, but the Corps also regulates additional wetlands not shown on the DEC maps. That is because DEC does not map wetlands smaller than 12.4 acres in size unless they are designated as 'wetlands of unusual local importance' (ULI). The National Wetlands Inventory, prepared by the U.S. Fish and Wildlife Service, is a good source of information about where these smaller wetlands occur, but they are not regulatory maps and landowners should not rely on them exclusively.

Wetland Classification

Different wetlands provide different functions and benefits and in varying degrees. The Act requires DEC to rank wetlands in classes based on the benefits and values provided by each wetland. The wetland class helps to determine the best uses for each wetland. Higher class wetlands provide the greatest level of benefits and are afforded a higher level of protection. Lower class wetlands still provide important functions and benefits, but typically require less protection to continue to provide these functions.

The permit requirements are more stringent for a higher class wetland than for a lower class wetland.

The 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.

More about Freshwater Wetlands Program: