T277 Landslides, Debris Flow, and Rock Fall: Processes and Hazards I

Wednesday, 28 September 2016
8:00 AM - 12:00 PM
Room 303

AN OVERVIEW OF SIGNIFICANT LANDSLIDE EVENTS IN WASHINGTON STATE

Paper number: T277-2
Program: Technical Sessions
Time: 8:05 AM – 8:25 AM

Authors

Abstract

Landslides are a significant and common geologic hazard in Washington State. The diverse geology, extended periods of precipitation, and varied topography allow for all landslide types and processes to occur. Substantial storm events can trigger thousands of landslides as observed in December 2007 when more than 1,600 landslides occurred in just the Chehalis River headwaters alone. A single storm in January 2009 caused more than 1,500 landslides greater than 5,000 ft2in size. From 1984 to 2014, 45 significant deep-seated landslide have occurred with direct costs ranging from 1 million to 110 million dollars. In 1998, the Aldercrest-Banyon landslide destroyed 138 homes, making it the second costliest landslide in U.S. history. In Washington, the risk to human life and infrastructure has increased as a result of the rapidly increasing population advancing into areas recognized as landslide prone. This presentation will briefly discuss examples of significant landslide events in Washington State and how these events, some quite large and damaging, eventually led to the development of the Washington Geological Survey’s Landslide Hazards Program.

Geological Society of America Abstracts with Programs. Vol. 48, No. 7

doi: 10.1130/abs/2016AM-286084

© Copyright 2016 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.