REPORT DOCUMENTATION PAGE

Form Approved
OMB No. 0704-0188

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PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS.

1. REPORT DATE (DD-MM-YYYY)
June 2021

2. REPORT TYPE
Computer Program Documentation

3. DATES COVERED (From - To)

4. TITLE AND SUBTITLE
HEC-WAT
Watershed Analysis Tool User's Manual
Version 1.1

5a. CONTRACT NUMBER

5b. GRANT NUMBER

5c. PROGRAM ELEMENT NUMBER

6. AUTHOR(S)
CEIWR-HEC

5d. PROJECT NUMBER

5e. TASK NUMBER

5f. WORK UNIT NUMBER

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES)
US Army Corps of Engineers
Institute for Water Resources
Hydrologic Engineering Center (HEC)
609 Second Street
Davis, CA 95616-4687

8. PERFORMING ORGANIZATION REPORT NUMBER
CPD-88

9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES)

10. SPONSOR/MONITOR'S ACRONYM(S)

11. SPONSOR/MONITOR'S REPORT NUMBER(S)

12. DISTRIBUTION/AVAILABILITY STATEMENT
Approved for public release; distribution is unlimited.

13. SUPPLEMENTARY NOTES

14. ABSTRACT
The HEC-WAT (Watershed Analysis Tool) software provides an interface that will streamline and integrate the analytical process using the tools commonly applied by the multi-disciplinary teams of USACE offices so that more efficient and coordinated modeling and planning may be performed. HEC-WAT is a tool that will help USACE offices perform water resources studies and/or system-wide studies, it can also be used for smaller studies as well, like a CAP (Continuing Authorities Program) study.

The HEC-WAT graphical user interface (GUI) streamlines and integrates a water resources study using software commonly applied by multi-disciplinary teams in USACE. HEC-WAT is not replacing existing software but rather it's an interface that allows unique pieces of software to work together (i.e., HEC-HMS, HEC-SSP, HEC-RAS, HEC-ResSim, HEC-DSSVue, HEC-FIA, HEC-EFM, etc.). Software is incorporated in HEC-WAT through the use of a plug-in. The plug-in concept means that HEC-WAT does not "know" anything about the software application code; the individual pieces of software provide the analytical computations, while HEC-WAT provides the framework to coordinate the study. The graphical user interface is illustrated and described in detail in this manual.

15. SUBJECT TERMS
HEC-WAT, software, interface, integrate, analytical process, tools, multi-disciplinary, teams, USACE, water resources study, CAP, study, graphical user interface, GUI, HEC-HMS, HEC-RAS, HEC-ResSim, HEC-FIA, plug-in, concept, computations, framework, hydrologic, hydraulic, economic, environmental, social impact analyses, modeling, results, models, reporting, visualization, data, sharing, rainfall-runoff analysis, river hydraulics, reservoir system analysis, flood damage analysis, flood impact analysis, statistical analysis, ecosystem response analysis, measures, trade-off analyses, alternatives, simulations, analysis periods, events, schematic, map layers, map windows, program order, reservoirs, levees, common computation points, stream alignment, impact areas, model linking, Without Project Conditions, panes, tabs, toolbars

16. SECURITY CLASSIFICATION OF:

17. LIMITATION OF ABSTRACT
UU

19a. NAME OF RESPONSIBLE PERSON

a. REPORT
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b. ABSTRACT
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c. THIS PAGE
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