Hoover dam bypass project was named the winner of Outstanding Civil Engineering Achievement Award


Recognized the most authoritative award in the American field of civil engineering with a history of over half century

Tokyo, April 4, 2012 - The Hoover dam bypass project - Colorado River Bridge constructed by the joint venture of Obayashi Corporation (President: Toru Shiraishi) and PSM Construction USA, Inc. in August, 2010 was named the winner of the 2012 Outstanding Civil Engineering Achievement (OCEA) Award.

The American Society of Civil Engineering (ASCE) annually recognizes an exemplary civil engineering project as the Outstanding Civil Engineering Achievement. Since 1960 the OCEA Award honors the project that best illustrates superior civil engineering skills and represents a significant contribution to civil engineering progress and society. The OCEA Award is the most authoritative award in the American field of civil engineering with a history of over half century. John F. Kennedy International Airport has been named the winner of OCEA in the past.

The OECA Award winner is chosen at the Outstanding Projects and Readers (OPAL) gala. This year's OPAL event, which was held on March 22 in Arlington, Virginia, the Hoover dam bypass project which Obayashi - PSM USA constructed was honored among 5 OCEA Award finalists, by the evaluation of reducing the threat of the terrorist attack against BCP of the surrounding area, adoption of the innovative hybrid structure and removing through traffic from U.S.93. In 2007, Obayashi was part of a team that won the OCEA Award for the Golden Gate Bridge Seismic Retrofit Phase II Project.

Evaluation point
  1. Reducing the threat of the terrorist attack

    The Hoover dam bypass helps to protect the security of the historically important dam by removing through traffic from U.S. 93, thereby reducing the vulnerability of the dam to a terrorist attack and safeguarding an important supply of water and the most sustainable supply source of electricity for the entire Southwest.

  2. Adoption of the innovative hybrid structure

    (1)Longest arch concrete bridge in the Western hemisphere (span: 1,090 ft)
    (2)Highest precast concrete column in the world (pier: maximum 285 ft)
    (3)First steel and concrete hybrid arch bridge in the United States
    (4)Construction in a harsh environment (gorge below with rock cliffs, high heat, high wind)

  3. Removing through traffic from U.S.93

    Hoover dam bypass succeeds in leading most of common vehicle flow to the bypass though the dam which is connecting the Nevada and Arizona Approach highways, caused chronic congestion by both common vehicle and tourist vehicle going to sightseeing.

Outline of project
  • Project name: Hoover dam bypass project
  • Location: Provincial boundary of U.S. state of Nevada and Arizona
  • Client: Federal Highway Administration
  • Contractors: Obayashi Corporation 75%, PSM Construction USA 25%
  • Work period: February, 2005 to August, 2010 (67months)
  • Structure/Scale: Reinforced concrete, Total length 1,900 ft, Width 88 ft (span: 1,090 ft)


Award ceremony

Award ceremony

Hoover dam bypass

Hoover dam bypass