Following a local megathrust earthquake event, subsequent tsunami inundation waters will reach the coastline of Seaside, OR within 10 minutes and the tsunami safety zones in 30 minutes. To evaluate the effort required to Page 9 of 11 2022 Spring Symposium Proceedings reach the safety zones, I walked and timed the entire length of all primary tsunami evacuation routes in Seaside. Using a least-cost distance (LCD) model, I used a global positioning system (GPS) watch to record the paths, times, and slopes for each route. I used the watch heart-rate monitor to maintain a steady expenditure of energy, sustaining a constant heart-rate within 110-120 beats per minute. This necessitated walking slower in difficult terrain and steep slopes, and faster on the flatter, paved surfaces. The data helped establish a reliable baseline for travel speeds and speed conservation values (SCV) for the varying terrains and slopes. Since travel speeds vary greatly through a given path, I applied modifiers to each of the individual route segments. This allowed me to evaluate how the overall evacuation times were affected by changing the energy expenditure. By comparing the evacuation times against the water arrival times, I was able to identify the level of effort required to safely evacuate each region of Seaside, OR during a tsunami. The data shows that the routes for the most populated regions of Seaside will require a moderate to high level of effort to successfully reach the safety zones before inundation waters arrive. Any delays caused by poor signage, traffic, or obstacles will be costly.