Pedestrian Travel-Time Maps for Unalaska/Dutch Harbor, Alaska: An anisotropic model to support tsunami evacuation planning

A.E. Macpherson et al.
Wed, 22 Apr 2026 17:17:12 PDT

Tsunami-induced pedestrian evacuation for the community of Unalaska/Dutch Harbor is evaluated using an anisotropic modeling approach developed by the U.S. Geological Survey. The method is based on pathdistance algorithms and accounts for variations in land cover and directionality in the slope of terrain. We model evacuation of pedestrians to the tsunami hazard zone boundary and to predetermined assembly areas. Pedestrian travel-time maps are computed for two cases: for travel across all viable terrain or by roads only. Results presented here are intended to provide guidance to local emergency management agencies for tsunami inundation assessment, evacuation planning, and public education to mitigate future tsunami hazards. This report was funded by the National Tsunami Hazard Mitigation Program grant to the Alaska Division of Homeland Security and Emergency Management and University of Alaska Fairbanks from the Department of Commerce/National Oceanic at Atmospheric Administration (NOAA). This does not constitute an endorsement by Alaska Earthquake Center (AEC) or NOAA.