You hang on and keep getting inundated until FEMA finally buys you out. I have acquaintances in West Virginia who have been flooded out by five 100 year events in the last 30 years. Once hardworking and self reliant, they turned into professional victims and procurers of government money. The trap of being trapped.
FEMA is already on site as of a few days ago.
Voluntary evacuations today for the town of Maxwell
http://www.foxnews.com/us/2017/02/18/latest-voluntary-evacuations-asked-in-california-town.html