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This memo was superseded the 08/18/09 memo Distribution of HY-8 Culvert Hydraulic Analysis Program, version 7.2

DOT LogoMemorandum
U.S. Department of Transportation
Federal Highway Administration

Subject: ACTION: Distribution of HY-8 Culvert Hydraulic Analysis Program, Version 7.1
Date: July 1, 2008
From: /S/ Original signed by M. Myint Lwin, P.E., S.E.
Director, Office of Bridge Technology
In Reply Refer To:HIBT-20
To: Associate Administrator for RD&T
Directors of Field Services
Federal Lands Highway Division Engineers
Division Administrators

The Office of Bridge Technology is pleased to announce the release of version 7.1 of the HY-8 Culvert Hydraulic Analysis Program (HY-8 7.1). The HY-8 7.1 represents the second phase of the FHWA’s multi-phase upgrade of its culvert hydraulics software approaches and protocols. Notable new features completed during this phase include:

  • Incorporates energy dissipater module;
  • Performs hydraulic analyses of embedded culverts;
  • Allows use of modified outlet loss coefficients;
  • Incorporates dynamic culvert shape database with new materials; and
  • Implements various improvements, technical updates, and bug corrections.

The HY-8 7.1 has on-line Help that assists users in understanding software operations and features. The technical methods applied in HY-8 are based on the FHWA publications: “Hydraulic Design Series 5: Hydraulic Design of Highway Culverts” (HDS-5), May 2005 and “Hydraulic Engineering Circular 14: Hydraulic Design of Energy Dissipaters for Culverts and Channels” (HEC-14), Third Edition, July 2006.

Attached to this memorandum is a copy of a “HY-8 Quick Start” document that provides information on background; program downloading and installation; some important differences between older versions and HY-8 7.1; and ways to report bugs or other problems.

A copy of this memorandum and attachment is being e-mailed directly to the hydraulics unit in each State department of transportation.

If you have any questions, please contact Mr. Joe Krolak of my staff at (202) 366-4611.

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Joe Krolak
Office of Bridges and Structures

Updated: 04/07/2011

United States Department of Transportation - Federal Highway Administration