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Hydraulics Engineering Publications

Title: Culvert Design for Aquautic Organism Passage

Description: HEC-26 presents a stream simulation design procedure, methods, and best practices for designing roadway culverts to facilitate aquatic organism passage (AOP). Fish species have been the focus of most AOP efforts over the years and much has been learned about fish specifically. Therefore, many of the references to AOP in this manual derive directly from what is known about fish passage. However, recognizing that many other organisms also transverse stream crossings, the FHWA intends HEC-26 to encompass the broader scope of general AOP.

HEC-26 is not intended to conflict with, replace, or override accepted AOP guidance and procedures adopted in particular locations. The FHWA intends to update future HEC-26 editions to reflect advances in AOP knowledge and improvement of methods.

HEC-26 presents a bed stability-based approach that accounts for the physical processes related to the natural hydraulic, stream stability, and sediment transport characteristics of a particular stream crossing. The HEC-26 approaches do not require specific information on fish, or other aquatic organisms, but allows incorporation of such information when required.

FHWA Publication Number: HIF-11-008

Publication Year: 2010

Document Links: PDF (8.4 mb)

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Updated: 09/06/2013

United States Department of Transportation - Federal Highway Administration