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. i . . . pollutants is sediment. When soil is eroded, sediment accumulates in downstream waterways, settling out where the, river slows down, such as where it enters a lake. Sedimentation will gradually fill in channels and lakes, reducing their ability to cany or store flood waters. BMPs reduce erosion'and sedimentation by two techniques: minimizing erosion with vegetation, arid captUring sediment before it leaves a site. Slowing runoff on its way to a dfainage charinel increaSes irifiltration into the soil and minimizes the loss of topsoil from erosion and the resulting sedimentation. Runoff can be slowed down with vegetation, terraces, contour strip farming, no-till farm practices, and impoundments (sediment basins, farm ponds, wetlands, etc.). BMPs can also be incorporated into retention and detention basins, drainageways, and other parts of new developments. They clean stonnwater runoff by filtering it or letting pollutants settle to the bottom of a basin before it is drained. Because of the need to improve the water quality in our rivers and lakes, several. state and federal laws mandate the use of best management practices for new developments and various land uses. Specific BMPs and structural measures may be required on industrial sites, mined lands, construction sites, farms, forested areas, and intensively used public lands. To F"md Out More .. .. Local and regional stormwater or sanitary agencies can give you infonnation about stonnwater management. Soil and Water Conservation Districts and their Natural Resources Conservation Service staff have both theexpernse in watershed measures and the contacts with watershed landowners. State environmental protection or natural resources agencies can provide guidance' on best management practices. Know Your Watershed is another group that~ help. Wetlands protection Wetlands is the collective tenn for marshes, swamps, bogs, and similar areas found in flat vegetated areas, in depressions in the landscape, and between dry land and water along the edges of streams, rivers, lakes, and coastlines. Wetlands filter runoff and adjacent surface waters to protect the quality of lakes, bays, and rivers, and protect many of our sources of drinking water. They can store large amounts of flood waters, slowing and reducing downstream flows. They can protect shorelines from erosion. Wetlands serve as a source of many commercially, and recreationally valuable species of fish, shellfish, and wildlife. Section 404 of the Clean Water Act regulates the discharge of dredged and fill material into waters of the United States, including wetlands. For purposes of the regulatory program for Section 404, wetlands are defined as areas that are inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions. Activities in waters of the United States that are regulated under this program include fill for development, water resource projects (such as dams and levees), infrastructure development (such as highways), and conversion of wetlands to uplands for farming and forestry. The Section 404 program is jointly administered by the U.S. Army Corps of Engineers and the U.S. Environmental Protection Agency. The Corps administers the day-to-day program, including permit decisions. The EPA develops and interprets the environmental criteria used in evaluating Section 404 17