Survivors in California's wildfires are facing hard choices — rebuild as quickly and cheaply as possible, or rebuild safer for the next fire.

Last month's devastating wildfires in Northern California killed 43 people and destroyed nearly 9,000 homes and other structures.

In the hard-hit city of Santa Rosa, city officials are pledging to speed rebuilding for residents of burned housing developments there.

Some wildfire experts are urging authorities to look hard at rebuilding in a more fire-safe manner. Studies by the U.S. Forest Service and University of Wisconsin show burn areas in cities tend to build more densely than before after wildfires. Fire expert Anu Kramer with the University of Wisconsin says survivors tend to make only the fire-safety improvements that regulations require, despite the lingering fire risks.