A mix of brute force and cutting-edge technology enabled contractors to replace a large portion of Oroville Dam’s spillway chute in just 165 days, meeting a Nov. 1 deadline set in anticipation of the start of northern California’s winter rainy season.
If initial lessons included in an interim status report on the cause of February’s failure of the main spillway at California’s Oroville Dam are heeded, hundreds of U.S. dams more than 50 years old may have to be re-examined and upgraded.
After armoring the damaged Oroville dam spillway, California Department of Water Resources is draining the lake at a rate of 40,000 cubic feet per second.
After more than 188,000 people evacuated from central California towns north of Sacramento, crews at Oroville Dam on Feb. 13 scrambled to fill erosion that developed hours after an emergency spillway was put into service for the first time in the dam’s 50-year history.
When Michael Braden took over as U.S Army Corps of Engineers’ divisions chief for the Olmsted Locks and Dam in 2013, job No. 1 was getting the $3.1-billion project back on schedule.
Faced with warnings of an imminent, catastrophic collapse of the earthfill structure causing widespread devastation, the Iraqi Ministry of Water Resources on March 2 signed up Italy’s Trevi Group to stem leaks under the dam and repair a bottom outlet floodgate.