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Environmental Modeling Community of Practice

BASINS Case Study

EPA developed a case study document for Cottonwood Creek Watershed, Idaho County, Idaho, to demonstrate the use of BASINS in developing a TMDL. Although the Cottonwood Creek case study was developed using BASINS version 2.0, the general concepts and procedures should still hold for the current version of BASINS. EPA’s Office of Science and Technology was requested by the Idaho Division of Environmental Quality (IDEQ) to help develop a bacteria TMDL for Cottonwood Creek, Idaho using EPA’s BASINS software. The goals of this project were to determine the source of the high bacteria concentrations, estimate bacteria loadings, and determine load reductions needed to meet State water quality criteria.

EPA produced a Step-by-Step Guide for the Cottonwood Creek Watershed case study that provides instructions on how to reconstruct, in specific BASINS and NPSM projects, the work products described throughout the modeling report.

  • Download the Step-by-Step Guide BASINS Case Study 1"Cottonwood Creek Watershed, Idaho County, Idaho" .
  • Download the BASINS Case Study Support Files(64 pp, 3 MB) Zip file .

Note: The Cottonwood Creek case study was developed using BASINS version 2.0, but the general concepts and procedures demonstrated in this case study are still applicable to later versions of BASINS.

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