A moderate earthquake Thursday afternoon shook a wide swath of Northern California, rattling homes and businesses from Redding to Elk Grove and shaking workers in downtown Sacramento high-rises. The 5.5 magnitude quake, centered in the waters of Lake Almanor in northwestern Plumas County struck at 4:19 p.m., according to the U.S. Geological Survey. The epicenter was 23 miles southeast of Lassen Peak, 28 miles west-southwest of Susanville and 50 miles northeast of Chico. It was felt about 120 miles south in Sacramento and Elk Grove, north to Redding and east to Reno.
Of particular note is Lake Almanor is highest of all the lakes that feed into the Oroville Dam by way of the Feather River. The dam that holds Lake Almanor back is a very old dam which is need of major repairs. There are a series of dams down the Feather River from Lake Almanor that serve as breaks as water flows through the Feather River Canyon to Lake Oroville.
If there was to be major damage to the Lake Almanor Dam and the dam was to break then the rush of water down the Feather River would be catastrophic to the Oroville Dam. In 2017 the Oroville Dam failed during heavy rains while at maximum capacity of 900 ft. The dam failure on February 2017 forced the emergency evacuation of over 280,000 people. It was the Sheriff of Butte County who had to threaten the arrest of California Department of Water (DWR) officials to force them to open the spillway gates which sent water over the damaged main spillway after DWR officials had recklessly allowed water to overtop the emergency spillway.
Was the Decision by the DWR to Overtop the Dam a Deliberate Act to Destroy the Dam?
The overtopping caused excessive damage to the soil in front to the emergency spillway causing a condition known as head cutting, where the water carves out the soil thus undermining the emergency spillway. Butte County Sheriff Kory Honea is credited with saving the lives of not just those 280,000 people who evacuated but the potential large loss of life in the greater Sacramento area.
It needs to be noted the Oroville Lake reservoir’s capacity is 900 feet and is near maximum capacity at 887 feet with inflows double the dams ability to release water. To many observers of the Oroville Dam this is now a ticking time bomb considering the spring melt hasn’t even started.
