iRICSoftware
LatestWindows 64bitapprox. 325 MB2026-08-01
iRIC 4.2Download
Solver1DOther tools

Culvert Analysis Program (CAP)

Culvert flow and stage analysis (USGS)

U.S. Geological Survey Culvert Analysis Program (CAP)

Developed by: USGS

What is the Culvert Analysis Program (CAP)?

The Culvert Analysis Program (CAP) is a solver developed by G.L. Bodhaine at the U.S. Geological Survey (USGS) for developing rating curves for a wide variety of culvert and culvert approach types. The solver was subsequently correct and improved by Janice Fulford of the USGS and then prepared and further corrected for use in iRIC by Keisuke Inoue of Mizuho Instrumentation and Research with direction from Jonathan Nelson, Bob Holmes and many other users at the USGS. Given a suite of information about culvert geometry, approach details and more, the solver produces a culvert rating that predicts culvert flow rates as function of water-surface elevations.

Updated Version of the Culvert Analysis Program (CAP 2021)

CAP 2021 addresses several known computational issues in previous versions of the software and adds support for non-plate corrugated metal pipe arches. CAP version 2021 has been integrated into the International River Interface Cooperative’s (iRIC) numerical simulation software platform as one of several available solvers beginning with iRIC version 4.0. The iRIC software provides a graphical user interface (GUI) front-end for CAP. **Versions of CAP that predate version 2021 should no longer be used.**Most of the updates correct known inconsistencies with discharge computations for culverts, as documented in Techniques of Water-Resources Investigations of the United States Geological Survey, book 3, chapter A3, "Measurement of Peak Discharge at Culverts by Indirect Methods” (Bodhaine, 1968).

 

This page was imported from the current site and is awaiting review by the solver developer. Page on the current site

Releases and downloads

8

Distribution files are available after signing in with iRIC ID (manuals and examples are open to everyone).

Why sign in: so we can notify you of updates, and to show the project is used.

Installer

Apr 10, 2018CAP DocumentationJAMembers onlyGet
Apr 10, 2018CAP DocumentationENMembers onlyGet

Manual

Apr 10, 2018User’s Guide to CAP, Version 97-08JAMembers onlyGet
Apr 10, 2018User’s Guide to CAP, Version 97-08ENMembers onlyGet

Examples and tutorials

Apr 10, 2018CAP Tutorial 1 dataJAMembers onlyGet
Apr 10, 2018Culvert Analysis Program (CAP) Tutorial 1JAMembers onlyGet
Apr 10, 2018Culvert Analysis Program (CAP) Tutorial 1ENMembers onlyGet
Apr 10, 2018CAP Tutorial 1 dataENMembers onlyGet