2014/05/28 Council Agenda Packet

Introduction Frequent landslides along the railroad corridor, especially between Seattle and Everett during the wet winter season pose periodic service interruptions for passengers on the Amtrak Cascades, Amtrak Long Distance, and Sounder. Landslides result in rail closures and emergency project activities every year, particularly during the rainy season from October to April. Disruption of rail service within the Seattle to Everett corridor has been especially problematic, with a record number of annulled and disrupted daily passenger trains (sum of both Sounder and Amtrak Cascades trips) due to landslides in 2013. At the request of the Washington State Secretary of Transportation, the Washington State Department of Transportation (WSDOT) initiated a joint work group effort with BNSF Railway Company (BNSF), Amtrak, Sound Transit, and local jurisdictions and stakeholders called the Landslide Mitigation Work Group. The mission was to investigate contributing factors to landslides within the corridor and determine a path to solutions. The Work Group developed the Landslide Mitigation Action Plan to evaluate causes of landslides within this 26.6- mile-long railway corridor (Figure 1), and form reasonable mitigation strategies to reduce impacts to the traveling public. The extent of the study area was defined by the high frequency of events. Landslides within the study corridor are triggered by a combination of factors including climatic/hydrologic factors (e.g., heavy or prolonged precipitation during the rainy season), geomorphic factors (i.e., steep topography), geologic conditions and impacts from human activities. Isla ". my Study Corridor Ktsap County Bainbridge Island YGng unt;d 5 Mu kilteo Snohomish C % n Lwinwood r Brier Mountke Terrace 3 f/ Lake Forest Park Shorelune 12 [� Kenmore Figure 1. Landslide Study Corridor 1.5 3 6 Miles III Creek L Legend • Mile Posts +—l- Railroads rd Incorporated Cities Counties tl i-Mrrevuel invilk. 1