A.D. 900 caused uplift that triggered a tsunami in central Puget Sound and probably also caused landslide-generated waves in Lake Washington. Tsunamis from plate-boundary earthquakes probably account for sand sheets on Whidbey Island and the head of Discovery Bay. Quaternary Research, v. 54, p. 218-227. Tsunamis in Puget Sound require understanding the hazard, planning and mitigating for it, and having the warning systems and communication, including education, in place to handle the disaster. Tsunami model simulations.
Planning exercises emergency managers use to identify issues and for training.
These tools require a basic understanding of tsunamis and where they can happen. Areas at risk are shorelines, ports and harbors, coastal rivers and lakes. Tides, weather, and time of day also determine the size of a tsunami in any of these areas. Further management information can be drawn from NOAA s Puget Sound Tsunami Model, which uses a 7.6 earthquake on the Seattle Fault to simulate the results of an earthquake-induced tsunami. The model has shown that a 7.6 quake would unleash a dangerous tsunami that would strike the Seattle Waterfront only 2.5 minutes after the earthquake hit.