This video is an introduction to wetland delineation and regional supplements. For detailed information on this topic please visit the U.S. Army Corps of Engineers' website. How do we identify wetlands, and why is that important? And – why does the Corps of Engineers care about identifying wetlands? One of the laws that governs the Corps’ regulatory program is the Clean Water Act of 1972. Section 404 of the law sets guidelines for protecting the nation’s waters from damage that results from the discharge of dredged or fill material. The Corps of Engineers regulates, through Department of the Army permits, activities that could result in pollutants being placed in the nation’s waters. Such activities may include dredging waterways for navigation, clearing land to prepare for development, and constructing roads, levees, dikes and dams. While waters such as streams, rivers and lakes are easy to identify, wetland characteristics are not always as obvious. That’s right. In fact, wetlands are not always “wet.” A wetland is an area that is inundated, or covered by, water – but it doesn’t necessarily mean that it is soaked all the time. Water may saturate a wetland either on a permanent or periodic basis. But regardless of their degree of wetness, wetlands are a valuable and important part of the ecosystem. Wetlands perform a variety of functions that are important for environmental health. They provide food and habitat where a variety of species nest, reproduce and raise their young and where they hide and rest. They protect from wave action that erodes the shoreline and threatens shoreline stability. They serve as storage areas to hold storm and flood waters, preventing them from spreading, damaging property and potentially taking lives. They work as nature’s filter, purifying water as it passes through them; and as a natural recharge area – where ground water and surface water meet. Because wetlands are so important, and because the Corps administers the program that permits activities in them, we identify them by looking for the characteristics that make a wetland, a wetland! This process is called wetland delineation because we delineate, or identify the boundaries of, wetlands by carefully examining three characteristics. One indicator of a wetland is the type of vegetation that grows in it. Wetland vegetation is called hydrophytic vegetation, because the plants grow in wet conditions. There are nearly 5,000 different wetland plant types in the United States. Another wetland indicator is soil. There are almost 2,000 wetland, or hydric, soils in the nation. Hydric soils may have a dark, dull color below the surface or may consist of sandy soil with streaks that stain when rubbed between the fingers. The soils may consist of decayed plant material and have the odor of rotten eggs. The third indicator is hydrology, or the presence of standing or flowing water at, below or above the surface of the soil. Water may not always be visible – sometimes water marks may be seen on trees, or small piles of debris may be piled against trees, rocks or other objects by the movement of water. Corps regulators identify wetlands by recording the types of plants and hydrology found on the site, and by comparing soil samples against a Munsell color guide – a soil research tool that classifies soil colors based on hue, lightness and color purity. Considering all of these factors together helps the Corps to accurately establish the boundaries of wetlands and determine whether or not they should be regulated under the Clean Water Act. One additional consideration in identifying wetlands is the regional differences in climate, hydrologic and geologic conditions, and plant and animal species across the country. A wetland in Mississippi, for instance, may be vastly different than a wetland in Alaska. For this reason, the Corps has developed a series of regional supplements to the wetland delineation guide, which are used by regulators in the wetland identification process. Regional supplements are available for: Alaska… the Arid West… the Atlantic and Gulf Coast… the Caribbean Islands… the Eastern Mountains and Piedmont Region… the Great Plains… Hawaii and the Pacific Islands… the Mid-West… the Northcentral and Northeastern United States…and the Western Mountains. The Corps developed these regional supplements as part of a nationwide effort to address regional wetland characteristics and improve the accuracy and efficiency of wetland delineation procedures. The U.S. Army Corps of Engineers takes great care in accurately identifying wetlands. This is an important step in our decision-making process, which provides opportunities for reasonable economic development while also protecting invaluable natural resources. [Footnote]: Before beginning any project in waters of the United States, be sure to find out if a Department of the Army permit is required. While this video attempts to give a general overview of the regulatory process, viewers should refer to the actual laws, regulations and guidance for complete and current information.