One year after the Oroville Dam’s concrete spillway ruptured on Feb. 7, 2017, crews working day and night have made the most critical repairs to what has become an $870 million project. Kiewit Corp. of Omaha, Neb., fixed the dam’s main spillway and an emergency spillway that also was damaged by unprecedented water releases forced by record rainfall in Northern California.
The work has continued in 2018, while the California Department of Water Resources (DWR) and Washington, D.C., discuss the extent to which the Federal Emergency Management Agency will pay for repairs. Meanwhile, Governor Jerry Brown signed legislation that codified the annual inspections DWR already conducts of the vast majority of the 1,249 dams the department oversees. The law requires “low hazard potential” dams be evaluated at least every other year.
Chico Enterprise-Record » The state Department of Water Resources does not expect to need to operate the Oroville Dam spillway anytime soon but is preparing in the event that it is necessary. Lake Oroville, currently at 773-foot elevation, could rise to 780-785 feet by the end of the month based on current projections.
Engineering News Record » Seemingly chaotic but actually highly choreographed and sequenced, the $1.1-billion Lake Oroville Spillways Emergency Recovery Project moves at an ultra-fast-track pace for one important reason: to repair the structures in time to protect cities, farmland and hundreds of thousands of people downstream of Oroville Dam before Northern California’s rainy season begins in November.
KRCR-TV » A bill that will allow citizen oversight of the Oroville Dam, and the public safety issues that come along with it, was signed into law this week by Governor Jerry Brown. Governor Brown signed into law Senator Jim Nielsen’s legislation to create the Citizens Advisory Commission for Oroville Dam. The measure empowers residents to be involved in public safety issues relating to the dam.
Chico Enterprise-Record » A 30-foot-wide section of temporary wall on the upper chute of the Oroville Dam spillway fell over late last week, the state Department of Water Resources confirmed on Monday. The collapse did not impact construction deadlines and resulted in no injuries, according to the department.
Construction Equipment » The California Department of Water Resources released a video showing before-and-after footage of construction on the Oroville Dam between July 2017 and 2018. The video offers a fly over of the wreckage, showing the dam’s giant canyons in 2017 juxtaposed with today’s smoothed-over layer of structural concrete.
CBS News » The average age of the 90,580 dams located across the U.S is 56 years, according to the American Society of Civil Engineers. ASCE says that in just 10 years, the number of at-risk dams has grown from 10 percent to 17 percent. One reason: Many are earthen dams, and the aging and crumbling structures are barely holding back nearby lakes and rivers.
Chico Enterprise-Record » An independent review board hired by the state Department of Water Resources Oroville Dam has released its first report with an eye toward improving the facility’s future operations. Among the suggestions: a second gated spillway, improved monitoring, and clear operational planning that takes into account the impact of climate change on the dam’s functions. (The webpage includes an embedded copy of the independent report.)
California Department of Water » Crews continue to place leveling concrete on the upper chute of the Lake Oroville main spillway, while other workers install forms over a structural rebar panel to prepare for the placement of more structural concrete. Meanwhile, mechanical demolition continues on the dentates, the big tooth-like structures that disperse water at the bottom of the main spillway.
Chico Enterprise-Record » The state Department of Water Resources has beefed up its response to the independent forensic report on what caused the Oroville Dam spillway failure last year. A revised dam safety policy, which will “further define roles and responsibilities” of the executive-level engineer, the chief dam safety engineer and other related State Water Project divisions, should be released by the end of the year.
Chico Enterprise-Record » The state Department of Water Resources says it may appeal a Butte County Superior Court judge’s ruling that allows the Butte County District Attorney’s environmental lawsuit to continue. This comes as Judge Stephen Benson overruled DWR’s demurrer, or objection to the lawsuit.
KCRA » The California Department of Water Resources said it is on track to meet the Nov. 1 deadline for its second phase of construction on the Oroville Dam spillways. Crews have conducted controlled blasts to remove temporary concrete on the primary spillway. Concrete is also being poured on the emergency spillway.
Chico Enterprise-Record » The agency has provided the department with about $139 million for emergency restoration work, including debris removal. FEMA is currently considering DWR’s request of $500 million to repair the main spillway and $75 million to repair the emergency spillway. The department is also seeking reimbursement for damages to Hyatt Powerplant, transmission lines and the Feather River Fish Hatchery.