We need to get people moving quickly and to save lives in case the worst case came to fruition. This is a very dynamic situation. This is a situation that could change very, very rapidly,” Butte County Sheriff Kory Honea said. Highway 49 in Nevada County was turned into one-way traffic. The evacuation order was extended to include Marysville and Yuba County around 5:45 p.m. PT. California Department of Water Resources officials had decided to use the emergency spillway to take pressure off the dam’s regular spillway, which developed a giant crater last week. That crater had been growing daily and the emergency spillway, but that also became compromised. Lake Oroville, a central piece of California’s government-run water delivery network, is one of California’s largest man-made lakes, and the 770-foot-tall Oroville Dam is the nation’s tallest. The actual crisis won’t be over soon, since Northern California is on pace for its wettest winter ever, Bill Croyle, acting director of the Department of Water Resources appreciated.