U.S. Department of Transportation
Federal Highway Administration
Hydraulic Engineering Circular No. 14, Third Edition
Hydraulic Design of Energy Dissipators for Culverts and Channels
National Highway Institute
Technical Report Documentation Page
1. Report No. 2. Government Accession No. 3. Recipient's Catalog No.
4. Title and Subtitle 5. Report Date
Hydraulic Design of Energy Dissipators for Culverts and Channels Hydraulic Engineering Circular Number 14, Third Edition
6. Performing Organization Code
8. Performing Organization Report No.
Philip L. Thompson and Roger T. Kilgore
9. Performing Organization Name and Address 10. Work Unit No. (TRAIS) 11. Contract orGrant No.
Kilgore Consulting and Management 2963 Ash Street Denver, CO 80207
12. Sponsoring Agency Name and Address
13. Type of Report and Period Covered
Federal Highway Administration National Highway Institute Office of Bridge Technology 4600 North Fairfax Drive 400 Seventh Street, SW Suite 800 Room 3203 Arlington, Virginia 22203 Washington D.C. 20590
Final Report (3rd Edition)
July 2004 – July 2006
14. Sponsoring Agency Code
Project Manager: Cynthia Nurmi – FHWA Resource Center Technical Assistance: Jorge Pagan, Bart Bergendahl, Sterling Jones (FHWA); Rollin Hotchkiss (consultant)
The purpose of this circular is to provide design information for analyzing and mitigating energy dissipation problems atculvert outlets and in open channels. The first three chapters provide general information on the overall design process (Chapter 1), erosion hazards (Chapter 2), and culvert outlet velocity and velocity modification (Chapter 3). These provide a background and framework for anticipating dissipation problems. In addition to describing the overall design process, Chapter 1 provides design examples tocompare selected energy dissipators. The next three chapters provide assessment tools for considering flow transitions (Chapter 4), scour (Chapter 5), and hydraulic jumps (Chapter 6). For situations where the tools in the first six chapters are insufficient to fully mitigate a dissipation problem, the remaining chapters address the design of six types of constructed energy dissipators. Although anyclassification system for dissipators is limited, this circular uses the following breakdown: internal (integrated) dissipators (Chapter 7), stilling basins (Chapter 8), streambed level dissipators (Chapter 9), riprap basins and aprons (Chapter 10), drop structures (Chapter 11), and stilling wells (Chapter 12). Much of the information presented has been taken from the literature and adapted,where necessary, to fit highway needs. Research results from the Turner Fairbank Highway Research Center and other facilities have also been incorporated. A survey of state practices and experience was also conducted to identify needs for this circular.
17. Key Word 18. Distribution Statement
energy dissipator, culvert, channel, erosion, outlet velocity, hydraulic jump, internal dissipator,stilling basin, impact basin, riprap basin, riprap apron, drop structure, stilling well
19. Security Classif. (of this report)
This document is available to the public from the National Technical Information Service, Springfield, Virginia, 22151
20. Security Classif. (of this page)
21. No. of Pages
Unclassified Form DOT F 1700.7 (8-72)
Reproduction of completedpage authorized
ACKNOWLEDGMENTS First Edition The first edition of this Circular was prepared in 1975 as an integral part of Demonstration Project No. 31, "Hydraulic Design of Energy Dissipators for Culverts and Channels," sponsored by Region 15. Mr. Philip L. Thompson of Region 15 and Mr. Murray L. Corry of the Hydraulics Branch wrote sections, coordinated, and edited the Circular....