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Environmental Modeling Community of Practice

What's Changed Between BASINS 4.1 and 4.5

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.

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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. See for more information.
  • 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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