AGRICULTURAL NONPOINT SOURCE POLLUTION (AGNPS)

• Format: Software
• Language: unknown
• Published: 2002
• Subjects: BIOSPHERE-HUMAN EFFECTS-AGRICULTURE; BIOSPHERE-HUMAN EFFECTS-POLLUTION; HYDROSPHERE-SURFACE WATER-SURFACE RUNOFF; TRANSIENT PHENOMENA-ANTHROPOGENIC-POLLUTION; Beaver Creek
• Online Access: http://oaspub.epa.gov/eims/eimsapi.dispdetail?deid=2916

Developed by the USDA Agricultural Research Service, Agricultural Nonpoint Source Pollution (AGNPS) model addresses concerns related to the potential impacts of point and nonpoint source pollution on surface and groundwater quality (Young et al., 1989). It was designed to quantitatively estimate pollution loads from agricultural watersheds and to assess the relative effects of alternative management programs. The model simulates surface water runoff along with nutrient and sediment constituents associated with agricultural nonpoint sources, and point sources such as feedlots, wastewater treatment plants, and stream bank or gully erosion. The available version of AGNPS is storm-event based; however, the AGNPS is storm -event based; however, the USDA will soon be releasing a continuous simulation version, ANNAGNPS. The structure of the model consists of a square grid cell system to represent the spatial distribution of watershed properties. This grid system allows the model to be connected to other software such as Geographical Information System (GIS) and Digital Elevation Models (DEM). This connectivity can facilitate the development of a number of the models input parameters. Two new terrain-enhanced versions of the model, AGNPS-C, a contour-based version, and AGNPS-G, a grid-based version, have been developed to automatically generate the grid network and the required topographic parameters (Panuska et al., 1991). The model also includes enhanced graphical representations of input and output information. AGNPS has been extensively used by resource agencies in Minnesota and surrounding States. It was also applied to develop cost-effective nonpoint pollution control alternatives in Idaho and Illinois and St. Albans Bay, Vermont. GIS was linked with AGNPS to model sediment loading to surface waters of the Wet Beaver Creek watershed of North-Central Arizona.