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WinTR-20 Watershed Hydrology

Material on this page relates to the latest version of WinTR-20, (ver 3.10).  click here for version 1.11

The Computer Program for Project Formulation Hydrology (WinTR-20) is a single event watershed scale runoff and routing model. It computes direct runoff and develops hydrographs resulting from any synthetic or natural rainstorm. Developed hydrographs are routed through stream and valley reaches as well as through reservoirs. Hydrographs are combined from tributaries with those on the main stream. Branching flow (diversion), and baseflow can also be accommodated. WinTR-20 may be used to evaluate flooding problems, alternatives for flood control (reservoirs, channel modification, and diversion), and impacts of changing land use on the hydrologic response of watersheds. The NRCS WinTR-20 version 3.10 computer program can be downloaded from this page.

A routine that allows the user to import NOAA Atlas 14 rainfall data for site-specific applications has been updated. The rainfall-frequency data will be used to develop site-specific rainfall distributions. The NOAA Atlas 14 text files and GIS data for selected states are available in the Support Materials for downloading and use in WinTR-20 Version 3.10. The NOAA Atlas 14 text files and supporting GIS files are packaged in a zip file for each state. An equivalent import program was developed to use rainfall-frequency data from the Northeast Regional Climate Center (NRCC). The NRCC has completed rainfall-frequency analyses for New York and New England states.

The WinTR-20 development team has appreciated all the testing and comments we have received to date. If you encounter any problems, or have comments on the version 3.10 computer program or enhancements to suggest please contact the WinTR-20 development team via e-mail to: WinTR-20 Team.

Download WinTR-20 installation file

Get download help here.


WinTR-20, Version 3.10, (for Windows7 and earlier operating systems)


WinTR-20 Support Materials

WinTR-20 Readme file
Latest version of the WinTR-20 User Documentation (under development)
Latest version of the WinTR-20 User Guide
References on Time of Concentration with Respect to Sheet Flow

NOAA 14 Data:         (data for states not listed is in development)
        AL  AK  AR  CA  DE  FL(DOC)  FL(GIS)  IA  IN  MD  NJ  NV  OH  PA  TN

NRCC Data:     CT  MA  ME  NH  NY  RI  VT


WinTR-20 Training Materials

Workshops and demos
Tutorial: WinTR-20 for WinDAM
Tutorial: WinTR-20 with ponds
Dimensionless Unit Hydrograph tables: DUHs for WinTR-20
Four example applications with advanced features (under development)

PowerPoint training Presentations:
        Module 1: Intro & Overview
        Module 2: Basic input & output
        Module 3: Advanced features
        Module 4: Computation methods
        Module 5: Use for small watersheds
        Module 6: Convert TR-20 data to WinTR-20 data
        Module 7: Import HEC-RAS cross-section data
        Module 8: Muskingum-Cunge Routing
        Module 9a: NOAA Atlas 14 Rainfall Distributions (Maryland)
        Module 9b: NOAA Atlas 14 Rainfall Distributions (Midwest, Southeast)
        Module 9c: NOAA Atlas 14 Rainfall Distributions (Ohio Valley and neighboring states)
        Module 9d: Import NOAA Atlas 14 Rainfall
        Module 10a: NRCC Rainfall Distributions
        Module 10b: Import NRCC Rainfall
        Module 11: Analyzing Principal Spillway, Stability, and Freeboard Storms
        Module 12: Sensitivity of input parameters
        Module 13a: Calibration (general)
        Module 13b: Calibration (Maryland)

The Natural Resources Conservation Service used government funds to develop the Technical Release 20 (WinTR-20) computer program. It may be downloaded for use and copying at no additional expense or license requirements.

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