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The BASINS 4 Documentation is found under the Help pulldown menu.

You will need Adobe Reader to view some of the files on this page. See EPA's PDF page to learn more.

BASINS Climate Assessment Tool

EPA developed the CAT tool for BASINS 4.0 in 2006. BASINS CAT provides a flexible set of capabilities for modifying historical weather data to create climate change scenarios for assessing the influence of climate variability and change on water quantity and quality using the Hydrologic Simulation Program—FORTRAN (HSPF) watershed model. The draft report provides technical information including a discussion of tool capabilities and a set of tutorials to support BASINS users interested in applying the CAT tool.

BASINS 4.0 Climate Assessment Tool (CAT): Supporting Documentation and User's Manual (Final Report).

BASINS Technical Notes

Note: References in the technical notes are made to NPSM (NonPoint Source Model) which was the predecessor to WinHSPF (Windows Hydrological Simulation Program - Fortran) in BASINS 3.0. Please substitute "WinHSPF" for "NPSM" in the Technical Notes.

Rates, Constants, and Kinetics Formulations in Surface Water Quality Modeling

Studies are reviewed in this USEPA publication to provide a comprehensive volume on state-of-the-art formulations used in surface water quality modeling along with accepted values for rate constants and coefficients. Topics covered include: dispersion, heat budgets, dissolved oxygen saturation, reaeration, CBOD decay, NDOD decay, sediment oxygen demand, photosynthesis, pH and alkalinity, nutrients, algae, zooplankton, and coliform bacteria. Factors affecting the specific phenomena and methods of measurement are discussed in addition to data on rate constants. 

Rates, Constants, and Kinetics Formulations in Surface Water Quality Modeling (Second Edition)Exit EPA Disclaimer 

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Hydromodification Modeling

Modeling the Impacts of Hydromodification (PDF) (83 pp, 840KB)

Land Use and Land Cover Analysis for Watershed Modeling (PDF)Exit EPA Disclaimer (21 pp, 2.4MB)—A method for determining the extent of effective impervious area, for use in watershed modeling.

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BASINS Case Study

Example Applications of Models

HSPF User Manual

PLOAD Users Manual

Note: If the BASINS program has been installed, the PLOAD Users' Manual can be found under the "/BASINS/docs/" folder.

Download Manual (PDF) (428K, 48 pp.) version 3.0 of PLOAD ArcView GIS Tool to Calculate Nonpoint Sources of Pollution in Watershed and Stormwater Projects Users' Manual

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BASINS 3.0 User Manual

Note: If the BASINS program has been install, the BASINS Users' Manual can be found under the "/BASINS/docs/" folder.

Download the entire manual (PDF) (343 pp, 4.4MB)

A printed copy of the BASINS 3.0 Users Manual is freely available from our Center for Environmental Publications. Go to the search publications page and enter the publication number: EPA823B01001. Also, a web version of the Users Manual is found under the "Help" pulldown menu in the BASINS project window.

  • Preface: Cover page, Acknowledgments, and Table of Contents
  • Section 1: Introduction
  • Section 2: System Overview
  • Section 3: Hardware and Software Requirements
  • Section 4: Installation
  • Section 5: Extension Manager(478 K)
  • Section 6: Assessment Tools
  • Section 7: Data Extensions
  • Section 8.1: Manual Watershed Delineation
  • Section 8.2: Automatic Watershed Delineation
  • Section 8.3: Predefined Delineation
  • Section 9: BASINS Utilities
  • Section 10: Watershed Characterization Reports
  • Section 11: Selecting Watershed and Instream Models
  • Section 12: References
  • Appendix A: GIS Data Dictionary
  • Appendix B: HSPF and Weather Data Files

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