Chico, Nov. 8 -- Amber Blood got to Chico on Nov. 8, 2018, wearing pink slacks and her favorite white peacoat. It was all she had left.

Blood was among tens of thousands forced to flee as a wildfire roared through Paradise and nearby communities in Northern California, killing 85 people and destroying roughly 19,000 buildings.

Nothing burned in Chico, the closest big city. And within hours, another city had moved in - filling up hotels, living in trailers, sleeping on friends' couches and buying up every available home, apartment and spare room.

A year later, most are still there. State officials estimate Chico has added 20,000 people, boosting the population from 92,000 to more than 112,000. The city didn't expect that number until at...