Feds order design for ‘immediate’ Oroville repairs
California must fix dam spillway so area residents can go home
The federal government ordered California to immediately design repairs to the Oroville Dam’s damaged primary and emergency spillways.
In a letter dated Monday, the Federal Energy Regulatory Commission ordered the California Department of Water Resources to “initiate immediate design of emergency repair to minimize further degradation” of both structures, which have been eroding as water flows out of Lake Oroville this week.
The primary spillway, which technicians use to release water from Lake Oroville into the Feather River as the lake’s water level rises, has a concrete bottom that has had a “gaping hole” in its floor since Feb. 7, officials said. Technicians reduced the amount of water flowing down that spillway and the lake’s level kept rising. On Saturday, the lake reached capacity and water began to flow down a dirt hillside known as the dam’s “emergency spillway.”
Monday’s letter orders the department to organize a board of at least five experts in structural engineering, spillway hydraulics and dam design and construction. They are to assess conditions at Oroville’s primary and emergency spillways and the Oroville Damadjacent Hyatt Power Plant and make recommendations about repairs and modifications.
California water officials continued to work to repair the emergency spillway as they brace for more rain later this week.
Chris Orrock, a spokesman for the California Department of Water Resources, said water is not going over the emergency spillway and erosion has stopped. Lake Oroville is at 889 feet and the goal is to drop the level to around 850 feet.
But a pair of storms are expected to hit California this week.
Evacuation orders were lifted Tuesday for communities below the Oroville Dam.
Orrock emphasized that the dam has not been compromised.
The nearly 200,000 evacuated residents were told Tuesday the order had been changed to an evacuation warning though it could be up to two weeks before they secure the eroded section of the emergency spillway enough to let them return to their homes.