INTEGRATING NONPOINT-SOURCE POLLUTION MODELING WITH A GEOGRAPHIC INFORMATION-SYSTEM

The major impediments in using computer models for simulating the cons equences of nonpoint source pollution are the intensive data requireme nts and time involved in compiling the model input file. These problem s can be overcome by integrating nonpoint source pollution models with geographic information systems (GIS). This paper presents a computeri zed system developed by integrating GIS and a dynamic, event-based, no npoint source pollution model. The GIS software used for the integrati on was pc-ARC/INFO (Environmental Systems Research Institute, Redlands , CA). Using the pc-ARC/INFO Simple Macro Language (SML), Pascal, and batch programming, a menu-driven system was developed that integrates the Agricultural Nonpoint Source pollution model (AGNPS) with pc-ARC/I NFO. Running on a DOS platform with 640 KB 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-A RC/INFO coverage and can be displayed as a map using the user-selected map format.