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Contract awarded by DWR to Kiewit Infrastructure West for repairs to Oroville Dam spillways
After two-plus months of headlines, the temporary evacuation of nearly 200,000 people and round-the-clock work to attempt to shore up what started as a crack and become a crater – officials with the Department of Water Resources (DWR) have awarded a $275 million contract to Kiewit Infrastructure West Co. for the repair work on Oroville Dam’s spillways.
Three bids were submitted to state water officials and Kiewit’s bid of $275,443,850 was the lowest responsive bid. The other bids were from Barnard Ames JV (MT) at $276,965,690 and Oroville Dam Constructors (CA) submitting at $344,129,100. All three bids outpaced DWR’s corrected engineer’s estimate of $231,715,373 for the massive job.
Although Kiewit Infrastructure West Co. is based in California, parent company Kiewit Corporation is an employee-owned Fortune 500 contractor based in Omaha, Nebraska. The privately held corporation is one of the largest contractors in the world.
Kiewit has been an integral part of the $900 million, multi-year work to improve the flood control and the safety of Folsom Dam in Sacramento. The project — a joint effort between the Army Corps of Engineers and the federal Bureau of Reclamation — required expedited action to reduce hydrologic (overtopping), seismic (earthquake), and static (seepage) risks. With a large downstream population, it had been deemed prudent to modify the dam’s facilities in an effort to improve public safety.
Kiewit Infrastructure was awarded a $255.1 million contract in May 2013, to complete construction on the new spillway at Folsom Dam. The new spillway was constructed to release water safely from Folsom Lake during high water levels to protect nearby communities.
Rep. Doris Matsui (D- 6th District-Sacramento) had said in a January 2016 Sacramento Bee article that the then ongoing work at Folsom Dam meant, “…we are one step closer to the completion of the spillway, which will more than double Sacramento’s current level of flood protection.”
In awarding Kiewit the Oroville Dam spillway project on Monday, the DWR instructed the contractor to commence work. The repairs are scheduled to begin immediately in order to have the spillway operational by November, the traditional start of the state’s winter rainy season. DWR is implementing its recovery plan to ensure the Oroville Dam system can safely accommodate potentially heavy inflows from the Feather River watershed to Lake Oroville and subsequent releases from the lake.
After California’s five-plus year drought, the 2016-17 rain year and its record-breaking precipitation caused severe complications for Oroville’s dam and spillways. Five days after the initial crack in the main spillway was exposed, the lake overflowed onto the never-before-used earthen emergency spillway causing erosion on the hillside below the concrete lip prompting the evacuation order for residents below the dam.
The complete replacement of both spillways will require more than a year due to the enormity of the project as well as the time limitations of the construction season. DWR reports that work has already started on portions of the work such as road construction and slope stabilization in and around future work areas. This work would need to be completed regardless of the spillway recovery design decisions.