Integrated geographic information system for modeling nonpoint source pollution events

The major impediments in using computer models for simulating the consequences of nonpoint source pollution are the intensive data requirements and time involved in compiling the model input file. These problems can be overcome by integrating nonpoint source pollution models with geographic information systems (GIS). A computerized system developed by integrating GIS pc-ARC/INFO and a dynamic, event-based nonpoint source pollution model is presented. Using the pc-ARC/INFO macro language, Pascal, and batch programming, a menu-driven system was developed that integrates the agricultural nonpoint source pollution model (AGNPS) with pc-ARC/INFO. Running on a DOS platform with 640 kbytes of memory, the integration prototype converts a set of pc-ARC/INFO coverages into an AGNPS input data file. The output from the AGNPS model is converted back into pc-ARC/INFO coverage and can be displayed as a map using the user-selected format