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BASINS Release 4.1 available on EPA Web Site

Post Date: September, 2013

EPA has released an enhanced version of the BASINS (Better Assessment Science Integrating point and Nonpoint Sources). BASINS version 4.1 includes numerous enhancements over Version 4.0 that update its underlying GIS software, update the watershed delineation utilities, and enhance several data management and analysis tools.

The most important changes in BASINS 4.1 include:

  • Built upon the latest stable release of the non-proprietary, open-source MapWindow GIS. The new Map Window interface has changed in appearance, but the main functions remain the same
  • Updated automatic watershed delineation tools to use TauDEM (Terrain Analysis Using Digital Elevation Models) version 5 from Utah State University. TauDEM is a software program that delineates watershed boundaries from topographic information such as elevation grids, slope and stream flow direction.
  • Made two of the main utilities, GenScn and WDMUtil, available as a separate download.
  • Included most of the functionality of GenScn and WDMUtil in the core BASINS user interface, making the separate programs unnecessary for most users.
  • Added DFLOW, a tool to estimate design stream flows for use in water quality studies.
  • Refined the Users Manual to match the current software.
  • Verified 64-bit compatibility and compatibility with Windows 8

BASINS was developed by EPA to assist states, local governments and watershed groups in their efforts to manage their watersheds and develop TMDLs. It does this by integrating environmental data, analysis tools, and watershed and water quality models. Directions for downloading the model and its associated documentation, as well as additional information, can be found on EPA’s BASINS website at:

The management of BASINS is being transitioned from the Office of Water to the Office of Research and Development’s Center for Exposure Assessment Modeling in Athens, GA. CEAM’s mission is to “meet the scientific and technical exposure assessment needs of the US EPA as well as state environmental and resource management agencies.”