An Oklahoma dam got its first “deep dive” safety inspection since it was built in 1973. This included a first look at the upstream low level outlet tunnel gate structure. Mead & Hunt faced record rainfall and used an underwater remote vehicle to complete a thorough investigation of the tunnel. Mead & Hunt received an Engineering Excellence Award from the American Council of Engineering Companies of Oklahoma for their role in the investigation of the Broken Bow Dam diversion tunnel.
The project received a Top 5 Honor Award from ACEC Oklahoma, qualifying it for national award nomination with ACEC. Since 1967, U.S. engineering firms have entered their most innovative projects and studies in ACEC’s Engineering Excellence Award program — the Academy Awards of the engineering industry — which honors the year’s most outstanding engineering accomplishments.
“Mead & Hunt’s excellent efforts on this investigation will allow the District to proceed to a semi quantitative risk-assessment of Broken Bow Dam to be performed at a later date,” says Christopher Hussin, Colonel, U.S. Army District Commander. “Their extensive investigation and analysis enhanced the safety of the Broken Bow Hydroelectric Dam.”
The 43 year-old Broken Bow Dam diversion tunnel in Tulsa is owned by the United States Army Corps of Engineers and is part of Broken Bow Lake, a popular place for tourists and nature enthusiasts to hike, birdwatch and enjoy the scenery. The dam provides hydroelectricity to nearby residents, flood control, water supply and cool water for a 12-mile long trout stream. If the dam were to fail or become unsafe, it would negatively impact recreational use, economic benefits and hydroelectric production.
Investigating the safety of this dam meant Mead & Hunt needed to overcome a few challenges, starting with an upstream tunnel and gate structure 170 feet below water. The use of the underwater remote vehicle for the inspection eliminated the need to empty the tunnel of water.
Only a month into the project record amounts of rain fell in southeast Oklahoma producing high water levels in the downstream tunnel. The weather delayed the inspection by two weeks, requiring a much greater level of coordination and side-by-side work between Mead & Hunt, its teaming partners and USACE.
Despite these unseen events, the investigation was completed on time and at the proposed cost. The project required coordinating multiple contractors for site visits and submittals, which had potential to delay the project. Mead & Hunt was able to manage these challenges and provide USACE with an analysis that will guide their decisions regarding Broken Bow Dam for years to come.