The maps take data from past disasters and apply it to future risk, but the calculations can get tricky — and political.

After hurricanes, government officials buy homes that are "hopelessly at risk" for future flooding and demolish them.

While rebuilding will take time, many small businesses have rebounded quickly.

Monica Pope, a Houston chef, has seen the food community in her town unite in recent years.

"Everyone becomes on edge when you hear any type of heavy rainfall," a Louisiana homeowner says.

High prices limit hording and increase supply. But that's bad for business, one expert argues.

Local congregations know the neighborhoods and have a built-in system for collecting and distributing donations.