The US Bureau of Reclamation has awarded construction contracts with a total value of over US$1M for safety work at dams in the states of Oregon and Idaho.

The largest contract, valued at US$938,742, was awarded to Kirby Nagelhout for work to correct safety deficiencies at Arthur R. Bowman Dam located on the Crooked River in Oregon.

The modifications will correct a hydrologic deficiency that was identified under USBR’s Safety of Dams Program which determined that during a large flood event Bowman Dam would be overtopped and could potentially lead to dam failure. The modifications include adding a 6ft high concrete parapet wall to the upstream crest of the dam and raising a portion of the spillway walls by 2ft. The contractor is expected to start in May 2011 with a completion date of November 2011.

The second contract – valued at $386,050 – was awarded to PNK Constructors, LLC for work to raise the crest of Anderson Ranch Dam on the Boise River in Idaho in order to address previously identified safety and security.

The existing dam crest will be raised by 4ft, and a 19.5 foot single travel lane will be constructed across the crest to accommodate semi-trailer trucks and other oversized vehicles. By raising height of the dam, USBR will address operational vulnerabilities related to motorized traffic traveling across the top of the dam.

Construction will begin in April 2011, and is expected to be complete by June 2011.