2014/05/28 Council Agenda Packet

Intermediate Strategies Capital Improvement Projects Capital improvement projects are intended to improve passenger service reliability by reducing the number and severity of track outages due to slope failures along the corridor. Projects are intended to prevent and minimize service -disrupting landslides by improving the overall slope stability and implementing measures, such as walls, to prevent landslide debris from impacting the tracks. Six mitigation projects funded by WSDOT's American Recovery and Reinvestment Act (ARRA) grants are in design and a minimum of three (funding dependent) are planned for construction between 2013 and 2016 (construction is currently underway on two of the six projects). The six sites were prioritized based on slide history (high frequency of slides and service disruptions), geotechnical investigation and constructability as well as budgetary, schedule and property ownership constraints. Improvements primarily involve removing slide material, terracing slopes, installing trench drains, installing catchment walls, installing slide fences and appropriately capturing and directing drainage from adjacent properties. Development of a Landslide Potential Assessment Model Work is being done to determine whether the likelihood of a landslide event can be reliably determined by gathering improved rainfall and soil moisture data, and by improving models used to monitor slide activity. The accuracy of the model will be assessed using historical and 2013- 2014 data. Work in 2013-2014 will focus on installing additional rain gauges at key locations in the corridor and working with the U.S. Geological Service (USGS) to update their model; validation of the model would take place in the 2014-2015 rainy season. This work will be complemented by efforts to improve slope stability at a number of locations in the corridor. Long -Term Strategies and Recommendations Continue community outreach and education efforts to the local communities along the corridor bluff. Recommendations include: • Update education and outreach materials based on community feedback gained through brochure survey, workshops and local jurisdiction interaction. • Provide support for community workshops. • Develop a streamlined permit process and funding source to implement drainage improvements and best slope management practices by landowners along the corridor. Explore solutions for long-term slide debris removal and restoration of near -shore processes, such as beach nourishment. Recommendations include: • Cooperatively develop restoration plan and updated permit process with agencies (Ecology and the Corps), BNSF, and local stakeholders (e.g. Puget Sound Partnership and Snohomish County Marine Resources Committee). Such solutions may not impact BNSF's operations or limit BNSF's ability to return its tracks to service under current regulatory structure. p. 26