California Today: Flood Risk Causes 100,000 to Evacuate. Here’s What We Know.

Thousands of people fled areas downriver from Lake Oroville on Sunday after a secondary spillway at the swollen reservoir was compromised, raising fears of a collapse that might unleash disastrous flooding. By late Sunday, after whole towns had emptied out, officials said the immediate danger appeared to have passed. Evacuation orders, however, remained in place until they could be sure. “There are still a lot of unknowns,” Sheriff Kory L. Honea of Butte County said at a news conference.