The DWR closed the main spillway on Monday so that they could fully evaluate the extent of the damage, and remove an estimated 1.5 million cubic yards of debris displaced by the break, more than enough to fill the 68,000-seat Houston Astrodome. When the spillway broke, billions of gallons of water tore off cement, trees, and earth and created the ravine visible in the video.
The event shut down the Hyatt Powerplant, a hydroelectric facility which helps regulate the reservoir's water level. Two other nearby hydroelectric dams, Thermalito Diversion Dam and Thermalito Pumping-Generating Plant also rely on Lake Oroville but continued to function through the crisis. If engineers cannot restore Hyatt's functionality in the next several days, the DWR will again regulate water levels using the damaged emergency spillway.
Since the main spillway has been closed, water levels have risen three feet to reach an elevation of 843 feet. Dam officials say that the dam will remain secure so long as water levels remain below 850 feet.
In addition to debris removal, the DWR is cooperating with the Department of Fish and Wildlife to rescue Chinook salmon and steelhead trout stranded in pools by the flooding. Fishing of these species is critical to the economy around Lake Oroville.
Water levels reached their highest point on February 11, at a frightening 901 feet, which flooded the spillway and prompted a three-day evacuation.
America's tallest dam, the Oroville structure was opened in 1968 and is one of some 4,000 dams across the country described as "deficient" and prone to failure by the American Society of Civil Engineers.
