Local tsunami evacuation analysis of Seaside and Gearhart, Clatsop County, Oregon

Report -- Plate 1. Modeled Pedestrian Evacuation Times at 4 Feet per Second During an XXL1 Local Tsunami Event, Seaside and Gearhart, Clatsop County, Oregon, All Bridges Intact -- Plate 2. Modeled Pedestrian Evacuation Times at 4 Feet per Second During an L1 Local Tsunami Event, Seaside and Gearhart, Clatsop County, Oregon, All Bridges Intact -- Plate 3. Modeled Pedestrian Evacuation Times at 4 Feet per Second During an L1 Local Tsunami Event, Seaside, Clatsop County, Oregon: Avenue U and Avenue G Bridges Removed -- Plate 4. Modeled Pedestrian Evacuation Times at 4 Feet per Second During an L1 Local Tsunami Event, Seaside, Clatsop County, Oregon: Avenue A, West Broadway, and Highway 101 Bridges Removed -- Plate 5. Modeled Pedestrian Evacuation Times at 4 Feet per Second During an L1 Local Tsunami Event, Seaside, Clatsop County, Oregon: Hypothetical Vertical Evacuation Structure at Convention Center All Bridges Intact -- Plate 6. Modeled Pedestrian Evacuation Times at 4 Feet per Second During an L1 Local Tsunami Event, Seaside, Clatsop County, Oregon: Hypothetical Vertical Evacuation Structure at Trendwest Resort, All Bridges Intact -- Plate 7. Modeled Wave Arrival Times for XXL1 Local Tsunami Event, Seaside and Gearhart, Clatsop County, Oregon -- Plate 8. Modeled Wave Arrival Times for an L1 Local Tsunami Event, Seaside and Gearhart, Clatsop County, Oregon -- Plate 9. "Beat the wave" map for the maximum-considered XXL1 tsunami scenario for Seaside - all bridges intact and assuming a 5-minute evacuation delay -- Plate 10. "Beat the wave" map for the maximum-considered XXL1 tsunami scenario for Gearhart - all bridges intact and assuming a 5-minute evacuation delay -- Plate 11. "Beat the wave" map for the maximum-considered XXL1 tsunami scenario for Seaside - only retrofitted bridges intact (12th Street and 1st Avenue brides over the Necanicum River; 12th Street and Broadway Street over Neawanna Creek) and assuming a 5 -- Plate 12. "Beat the wave" map for the maximum-considered XXL1 tsunami scenario for Seaside - only retrofitted bridges intact (12th Street and 1st Avenue brides over the Necanicum River; 12th Street and Broadway Street over Neawanna Creek) and assuming a 1 -- Plate 13. "Beat the wave" map for the maximum-considered XXL1 tsunami scenario for Gearhart assuming a 10-minute evacuation delay.by George R. Priest, Laura L. Stimely, Ian P. Madin, and Rudie J. Watzig.Title from PDF title page (viewed on July 24, 2020).This archived document is maintained by the Oregon State Library as part of the Oregon Documents Depository Program. It is for informational purposes and may not be suitable for legal purposes."he objective of this study is to provide local government with a quantitative assessment of the difficulty of evacuating Seaside and Gearhart for the XXL1 and L1 scenarios in order to evaluate mitigation options such as evacuation route improvement, better wayfinding, land use planning actions, and implementation of vertical evacuation. We achieve the objective by 1) using the least cost distance (LCD) approach of Wood and Schmidtlein (2012) to provide estimates of walking times to safety, here defined as 20 feet beyond the inundation zone, for every place of origin in the community, 2) illustrating how quickly the wave front of an L1 or XXL1 tsunami advances across the area after the causative earthquake, and 3) determining whether an evacuee can stay ahead of the tsunami all the way to safety on the routes defined by the LCD analysis. The latter method is implemented by a new approach termed "beat-the-wave" (BTW) evacuation difficulty analysis that shows minimum speed to stay ahead of the tsunami all the way to safety. We then summarize which parts of each city are most in need of tsunami hazard mitigation"--Page 3.Includes bibliographical references.Mode of access: Internet from the Oregon Government Publications Collection.Text in English