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What's Changed Between BASINS 4.1 and 4.5

This model is being distributed, maintained and actively supported by EPA.

Highlights
  • BASINS Home
  • What's Different about BASINS 4.5?
  • Framework and Features
  • User Information and Guidance
  • Download and Installation
  • Meteorological Data
  • Metadata
  • Model Plugins

BASINS 4.5 provides a number of significant improvements over BASINS 4.1. These improvements increase the functionality and applicability of BASINS. The major changes that have been incorporated into BASINS 4.1 are listed below.


Significant Improvements:

  • Complete replacement of all the data download libraries with the D4EM version of these libraries.  Data for Environmental Modeling, or D4EM, is a comprehensive set of tools that obtains and processes data to be used in mathematical environmental models. For more information, see Data for Environmental Modeling (D4EM).
  • Updates the HUC8 layer of the ‘Build New Project’ national map to use the March 2017 update of the Watershed Boundary Dataset (WBD).
  • Provides access to both National Hydrography Dataset Plus (NHDPlus) version 1.0 and 2.1 through the data download tool.
  • Updates the National Land Cover Database (NLCD) data download options to include 2011 land use and impervious area data
  • Updates the North American Land Data Assimilation System (NLDAS) download to allow access to the full suite of meteorological constituents needed for watershed and in-stream models, as well as a new option to adjust time from UTC to the project time zone.
  • In BASINS 4.5 Core, all model plugins are installed separately from the BASINS 4.5 Core install

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Last updated on January 2, 2025
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