Software Support for Watershed Modeling: The BASINS Experience

The U.S. Environmental Protection Agency's (EPA's) Better Assessment Science Integrating Point and Nonpoint Sources (BASINS) is a multipurpose environmental analysis system designed for use by regional, state, and local agencies performing watershed and water quality-based studies. It was developed by the EPA's Office of Water to facilitate examination of environmental information, to support analysis of environmental systems, and to provide a framework for examining management alternatives. BASINS integrates environmental data, analytical tools, and modeling programs under a Geographic Information System (GIS) environment to support development of solutions to watershed management problems and environmental protection. The first release of BASINS, in 1996, followed more than two decades of development of watershed models, along with rapidly expanding public databases and more recently developing GIS technology. Through the early 1990s researchers at institutions around the world recognized the potential for linking watershed models with GIS systems and databases. Concurrently, awareness of water quality issues and needs was growing through enforcement of the Clean Water Act. BASINS was conceived during that time as a system that could combine models and data through GIS to make watershed assessment and simulation of management alternatives more accessible for agencies across the United States. The current release of BASINS is based on a non-proprietary, open-source GIS foundation. The open-source framework of BASINS is designed around an extensible architecture that readily allows for the addition of new capabilities. BASINS encompasses a growing suite of watershed and water quality models, from sophisticated broad-spectrum watershed models to agricultural models to planning and management level models. New data types and analysis tools also continue to be added to BASINS. BASINS Development Philosophy Software Support for Watershed Modeling: The BASINS Experience Paul B. Duda, AQUA TERRA Consultants 150 E. Ponce de Leon Ave. Decatur, GA 30030 pbduda@aquaterra.com Build on existing, documented technology • Integrates existing models (i.e., HSPF, SWAT) • Incorporates national derived data layers (i.e., PCS, STORET...)