2014/07/16 Council Agenda Packet

including the impact to tourism, transportation and the economy. As mentioned earlier, this data is an indicator of those areas that may be impacted from the various sea level rise scenarios, but is not intended, nor is appropriate, to be used to estimate impacts to specific sites or facilities at a smaller scale. This data is useful, however, to illustrate the long-term planning needs and challenges to a region adapting to climate change. More research will be needed to better understand the level, duration and other aspects of potential inundation in these areas, which will in turn provide better information for use in the planning of potential infrastructure improvements to address these changes. Specific to transportation, examples of facilities and routes that may be impacted under these future sea level rise scenarios - and therefore are examples of the types of issues that will need to be addressed in a long-range planning process that incorporates adaptation to climate change - include the following: • Roadways such as East Marginal Way and State Route 99 in Seattle, State Route 3 in Bremerton and State Route 167 in Tacoma • The Washington State Ferry system and terminals • Amtrak and Sounder Commuter Rail • Trails such as the Mosquito Fleet Trail, the Foss Waterway Public Esplanade and the Duwamish Trail • Port facilities and operations These facilities are examples of the types of critical infrastructure that are expected to be at risk from a changing climate, and for which adaptive response may be necessary. These and other facilities represent important connections and mobility for people, freight and emergency services. This report does not formally quantify the localized impacts to employment or the land use characteristics of the areas potentially impacted by inundation. This conservative approach to the analysis is based on the scale at which such data are available. Employment and land use data are reported on the parcel level, and due to the fact that the sea level rise estimates and the underlying elevation data are not suitable for site specific analysis, this type of quantitative analysis was not completed. However, visual inspection of Exhibits 1-10 indicates that the areas that may be most heavily impacted by inundation include manufacturing and industrial centers, which could have an impact on the region's economy. Further discussion of the incorporation of adaptation within the transportation sector, both in terms of long-range planning as well as the design of individual facilities, is contained in Section 6. SECTION 4: ECONOMIC IMPACTS AND DISRUPTION TO THE TRANSPORTATION SYSTEM DUE TO FLOODING As discussed in Section 2, the region is already prone to flooding and has experienced numerous major flood events over the years. Among the many possible impacts from climate change, the region may also experience an increase in storms and other weather events, which can in turn trigger an increase in flooding. This section describes the economic costs and the disruption to the transportation system that the region has experienced in the last several years from major flood events, as an illustration of potential impacts the region may face in the future from a changing climate. Perhaps the most notable storm and flood events in recent years have been those that impacted Interstate-5 and Interstate 90. In particular, the events between December 2007 and February 2008 are described in the economic impact assessment report published by the Washington State Department of Transportation (WSDOT) in September 200811. In December 2007 a severe storm resulted in high winds, heavy snow in the Cascades, rain of up to 11 inches in the Puget Sound region, and flooding. Interstate 5 in the Chehalis area was inundated with up to 12 feet of flowing water due to flooding of the Chehalis River in Lewis County, and a 20-mile section of the freeway was closed for four days. Since Interstate 5 is the primary north -south corridor on the West Coast, freight movement was significantly impacted. Approximately 10,000 trucks each day were required to find alternate routes. These alternate routes effectively tripled the mileage for a trip between Seattle and Portland. The extra distance also added time — up to 8.5 hours for some trips — which is a significant impact for truck drivers due to federally mandated regulations for the length of driving time allowed before a rest period is required. In " Storm Related Closures of 1-5 and 1-90: Freight Transportation Economic Impact Assessment Report Winter 2007-2008. Washington State Department of Transportation Freight Systems Division. Olympia, Washington. L-18 Appendix L: Climate Change Background