When a catastrophic earthquake hits California, buildings will topple and potentially hundreds could be killed. But what gets less attention is the wrenching aftermath of such a huge temblor, which could leave whole neighborhoods torched by fires uninhabitable and hundreds of thousands of people without a home. Officials are grappling with where all these quake refugees would go. In the San Francisco Bay Area, more than 400,000 could be displaced in a magnitude 7 earthquake on the Hayward fault, which directly runs underneath cities like Berkeley, Oakland, Hayward and Fremont, said Ken Hudnut, the U.S. Geological Survey’s science advisor for...