Improving Culvert Performance with Diffusers and Energy Dissipators

Culvert and stormwater outfall performance presents challenges for hydraulic practitioners. Two challenges often encountered with culvert performance are inadequate capacity under outlet control and excessive energy at the downstream end of stormwater outfalls under inlet control. Previous research and applications have demonstrated that diffuser systems are a practicable option for increasing culvert and stormwater outfall capacity (see Special Note B). However, diffuser systems are an emerging technology, and additional methods and application guidelines are needed to support effective design and implementation. Current energy dissipator designs often result in large structures that are costly to construct and may require additional right-of-way. There is a need for design approaches that support more compact energy dissipator systems suitable for constrained right-of-way environments. It is important that such systems be adaptable for retrofitting existing culverts to mitigate scour issues. Advancements in computational fluid dynamics (CFD) modeling allow for efficient comparisons between initial prototype designs, saving time and money on physical modeling. Research is needed to provide hydraulic practitioners with a design and application guide for implementing (1) diffuser systems to increase capacity, and (2) compact energy dissipator systems for retrofitting culverts. OBJECTIVE: The objective of this research is to develop a guide for the design and application of culvert diffuser and compact energy dissipator systems. The guide will give hydraulic practitioners the methods needed to deploy these systems in new and retrofit projects.

• Record URL:
  • http://apps.trb.org/cmsfeed/TRBNetProjectDisplay.asp?ProjectID=5869
• Supplemental Notes:
  • Contract to a Performing Organization has not yet been awarded.

Language

• English

Project

• Funding: $800,000.00
• Contract Numbers:

  Project 15-88

• Sponsor Organizations:

  National Cooperative Highway Research Program

  Transportation Research Board
  500 Fifth Street, NW
  Washington, DC  United States  20001

  American Association of State Highway and Transportation Officials (AASHTO)

  444 North Capitol Street, NW
  Washington, DC  United States  20001

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Project Managers:

  Crichton-Sumners, Camille

  Wadsworth, Trey

• Start Date: 20260210
• Expected Completion Date: 0
• Actual Completion Date: 0

Subject/Index Terms

• TRT Terms: Culverts; Design; Disaster resilience; Dissipation; Fluid dynamics; Storm sewers
• Subject Areas: Bridges and other structures; Design; Highways; Hydraulics and Hydrology;

Filing Info

• Accession Number: 01956828
• Record Type: Research project
• Source Agency: Transportation Research Board
• Contract Numbers: Project 15-88
• Files: TRB, RIP
• Created Date: May 29 2025 12:56PM