The Significance of Wetlands

In their natural condition, wetlands supply numerous ecological, economic, and cultural benefits to local communities -- including water quality protection, flood control, erosion control, fish and wildlife habitat, aquatic productivity, and unique opportunities for education and recreation.

Water Quality Protection

Whether communities obtain their drinking water supply from groundwater wells or from reservoirs fed by surface waters, it is important to protect the many functions of wetlands in maintaining water quality. One of the most important functions of wetlands is the ability to maintain good surface water quality in rivers, streams, and reservoirs and to improve degraded surface waters. Wetlands do this several ways: 1) By removing and retaining nutrients. 2) By processing chemical and organic wastes. 3) By reducing sediment loads.

Wetlands are particularly good water filters. Due to their landscape position between uplands and deep water, wetlands intercept surface water runoff before it reaches open water and filter out nutrients, wastes, and sediments from flood waters. This function is important in both urban and agricultural areas.

In some places, wetlands contribute to the recharge of groundwater sources of drinking water. During periods of heavy runoff, such as major storms or snow-melt in the spring, wetlands adjacent to streams and in depressions collect excess water. When the water table drops, the water held in the wetlands infiltrates slowly back through the soil into the aquifer to replenish groundwater.

Flood Control

By temporarily storing and slowly releasing flood waters, wetlands help protect adjacent and downstream property owners from flood damage. Trees and other wetland plants help slow the velocity of flood waters. This action, combined with water storage, allows wetlands to lower flood heights and reduce the water's erosive force.

Wetlands in and downstream of villages are especially valuable for flood protection, since the impervious surfaces associated with development increase the rate and volume of surface water runoff, thereby increasing the risk of flood damage downstream.

Erosion Control

Wetland plants such as willows buffer stream banks against the forces of erosion by binding soil with their roots and by reducing current velocity and wave action. Bioengineering techniques -- coconut fiber mats used in combination with willow cuttings -- provide habitat and aesthetic values not afforded by structural shoreline protection measures such as rock rip-rap.

Aquatic Productivity

Wetlands are among the most productive natural ecosystems in the world. Certain types of wetlands rival the best cornfields in biomass productivity. A large volume of plant material isproduced annually by wetlands. The leaves and stems of wetland plants break down in the water to form small particles of organic material, called detritus. This enriched detritus serves as the base of an aquatic food chain, providing a principal food source for small aquatic invertebrates and forage fishes, which are in turn consumed by larger predatory fish, such as bass and trout.

Fish and Wildlife Habitat

Wetlands provide critical habitat for several animal species including the wood duck, muskrat, river otter, spotted salamander, and water snake. An estimated 43% of the nation's threatened and endangered species rely directly or indirectly on wetlands for their survival. The bog turtle, a candidate species being considered for federal protection, may be found in wet meadows throughout the watershed region. The northern monkshood, a threatened plant, is associated with wetlands in seeps and the headwaters of streams in the Catskills.

Inland wetlands provide nursery grounds and feeding habitat for freshwater fish. A variety of birds are associated with inland wetlands, including ducks, geese, redwinged blackbirds, and a large number of nesting songbirds. Many important recreational fish, including bass, spawn in the aquatic portions of wetlands. Trout, a coldwater species, benefit from cooler water temperatures provided by streamside vegetation along Catskill streams.

Quality of Life

Several recreational activities take place in and around wetlands. Wetlands serve as a location for hunting, fishing, and trapping. Trout fishing is very popular with local residents and visitors to the Catskill region. Wetlands provide an opportunity for other recreational activities like hiking, bird watching, and photography. Many people may simply enjoy the beauty and sounds of nature, and spend time walking or boating around wetlands. They can observe plant and animal life, frogs and turtles along pond and lake shores, or marsh marigold in spring or the crimson leaves of red maple in the fall. Wetlands provide unique educational opportunities for outdoor study and the appreciation of natural history, ecology, conservation, and biology by students of all ages.

Source: "The Significance of Wetlands" section excerpted from Wetlands in The Watersheds of the New York City Water Supply System, US Fish and Wildlife Service, 1996.

For more information on Catskill wetlands, please call Beth Gelber, Stream Management Program, New York City Department of Environmental Protection at (845) 340-7515.

Contents | Glossary | Activity 1 | Water Resources Home