Oroville Dam in Northern California is the tallest dam in the United States at 770 feet. In this flyover showing the continuing repair work on the dam's spillway, you can see just how enormous the structure is. In February 2017, the main and emergency spillways failed, leading to the evacuation of 188,000 people living near the dam. Repairs are expected to exceed $500 million. The project is on schedule to finish pouring concrete on the main spillway by Nov. 1, 2017.
Work to repair and reconstruct the main spillway at Oroville Dam has been under way since April 2017. By November 1, 2017, the main spillway at Lake Oroville is expected to be ready to handle releases of up to 100,000 cubic feet per second. When fully reconstructed, it's expected to handle 270,000 cfs, according to news reports. This video of the repair progress was posted October 17, 2017.
Randy Record, chairman of the Metropolitan Water District of Southern California, describes what comes next after Tuesday’s historic vote that drew protests and passionate testimonies from Delta Tunnels foes.
This September 25, 2017 video shows progress on the Oroville Dam spillway. In February, the spillway at the nation's tallest dam was damaged, placing tens of thousands of people in the Butte County community of Oroville under evacuation orders due to the threat of flooding. The crisis began after heavy rain from one of the wettest winters on record.
Fly right up the spillway at Lake Oroville as repairs continue during the week of September 11, 2017. In February, water flowing down the main Oroville Dam spillway during raging winter storms ripped a huge hole in that concrete structure.
Repairs continue at Oroville Dam. Anchors are placed, side walls are framed, and the first structural slab erected on the upper spillway. On February 7, 2017, dam operators released a gusher of water down the spillway to reduce water levels at Lake Oroville. The heavy flows coming down the spillway apparently exploited weak points in the concrete, and one section of the concrete chute was lifted up, creating a giant crater underneath. The spillway is now under repair in a race to finish before the next rainy season.
Oroville Dam spillway construction is progressing at a fast pace, according to the Department of Water Resources, as large volumes of concrete are placed in multiple areas of the flood control spillway throughout the day. The large void in the central area of the chute, shown in this video posted Sept. 2, 2017, is being filled with roller-compacted concrete, while leveling concrete is poured in the upper chute.