For Many U.S. Communities, There’s No Easy Path to Safety From Disasters

August 23, 2019

As the country enters peak season for major natural disasters, new research indicates which states and communities are the riskiest for those needing to evacuate whether from wildfires or hurricanes.

StreetLight Data Inc., a company that collects and analyzes data around mobility, unveiled the results of a new nationwide analysis of the top 100 communities with limited evacuation routes.

StreetLight Data’s evacuation route analysis revealed that the five U.S. states with the most evacuation-challenged communities are:

  • Florida (20 communities)
  • California (14 communities)
  • Arizona (8 communities)
  • Texas (6 communities)
  • Washington (6 communities)

Evacuation risk can apply to floods, fires, dam breaks, hurricanes, tornadoes, and other emergencies. The firm notes that communities and towns with limited evacuation routes can face challenges in getting residents to safety before a disaster hits, as happened in last November’s Camp Fire in Paradise, California.

StreetLight Data analyzed the 30,000 towns in the U.S. with populations under 40,000. Using its algorithms, StreetLight then ranked the top 100 by “evacuation risk” from a transportation perspective. Evacuation risk was determined by how many of the location’s daily trips enter and exit the town and via what routes, adjusted for the number of available exits and overall population. While several exits may exist, the analysis takes into account that a large percentage of vehicles choose only one preferred route. In addition to highways and larger roads, “exits” may also include dirt roads, ferries, and other secondary options.

According to StreetLight Data, the 20 U.S. communities with the most constrained evacuation routes are:

“As we head into peak season for several types of natural disasters, from fires to hurricanes, there is no better time to review our disaster preparedness across the country,” said Paul Friedman, StreetLight’s chief technical officer, and the study’s key analyst. “Transportation infrastructure, and sharing information about transportation options, is one part of the complex requirements of disaster and evacuation preparation.”

An interactive national map of the communities with the most limited evacuation routes is available here.

According to CAL FIRE, since January 1, 2018 there have been 3,572 wildfires that have burned more than 245,850 acres in California alone. Florida has been directly hit by far more hurricanes than any other state, according to the National Oceanic and Atmospheric Administration.

Additional takeaways of the analysis revealed that:

  • 29 states have at least one community on the 100 most-constrained list.
  • The five most-constrained communities are islands.
  • Two of the 10 most-constrained communities are landlocked. One of the three states with the most-at-risk communities is landlocked.
  • Many of the 100 most-constrained communities include canyons or localities by lakes with minimal exits.