Caltrans CCAP: District Interviews Summary October 2019 San Joaquin Council of Governments Climate Adaptation & Resiliency Study Climate Adaptation Report APRIL 2, 2020 1 Climate Adaptation Report March 2020 Contents Acknowledgements ....................................................................................................................................... 3 Executive Summary ....................................................................................................................................... 4 Introduction .................................................................................................................................................. 5 Methodology ................................................................................................................................................. 7 Vulnerability Assessment: Key Findings ...................................................................................................... 10 Gaps and Recommendations ...................................................................................................................... 16 Integrating Transportation Resilience into the Regional Transportation Plan (RTP).............................. 17 Next Steps ................................................................................................................................................... 18 Appendix A: Detailed Vulnerability Assessment Report ............................................................................. 20 Introduction ............................................................................................................................................ 20 Methods .................................................................................................................................................. 21 Vulnerability Assessment ........................................................................................................................ 32 A. Sea level rise and riverine flooding ................................................................................................. 32 B. Extreme precipitation events .......................................................................................................... 43 C. Wildfire ........................................................................................................................................... 47 D. Extreme Heat .................................................................................................................................. 51 E. Drought ........................................................................................................................................... 54 Priority Vulnerabilities ............................................................................................................................ 55 Appendix B: GIS Data Sources ..................................................................................................................... 62 Appendix C: Sea level rise and riverine flood risk exposure maps ............................................................. 63 Appendix D: Existing Adaptation Planning Efforts ...................................................................................... 68 Appendix E: Regional Climate Change Summit: Agenda and Notes ........................................................... 75 2 Climate Adaptation Report March 2020 Acknowledgements The study team included Christine Corrales, Isaiah Anderson, Ashley Goldlist, Kim Anderson, and Summer Lopez from SJCOG and Eliza Berry, Arleen O’Donnell, and Lindsay Dayton from Eastern Research Group, Inc. (ERG). The San Joaquin Council of Governments (SJCOG) thanks our working group for their valuable input throughout the vulnerability assessment process: • Altamont Corridor Express • California Department of Transportation • California Department of Transportation, District 10 • City of Lathrop • City of Lodi • City of Manteca • City of Ripon • City of Stockton • City of Tracy • Delta Stewardship Council • Port of Stockton • Reinvent South Stockton • San Joaquin County Community Development • San Joaquin Regional Transit District • Stockton Metropolitan Airport • Third City Coalition 3 Climate Adaptation Report March 2020 Executive Summary The San Joaquin Council of Governments (SJCOG) is committed to improving the resiliency of the county’s transportation system in the face of climate impacts. This Climate Adaptation and Resiliency Report assesses the vulnerability of the San Joaquin County transportation system to sea level rise and riverine flooding, extreme precipitation, wildfire, extreme heat and drought. The study considered these vulnerabilities within the context of existing hazards and climate impact planning efforts in order to identify and prioritize additional adaptation planning and actions. Given SJCOG’s responsibility for producing the Regional Transportation Plan (RTP), the study team also identified opportunities to further integrate resiliency into RTP transportation project prioritization and design. The project began with a criticality assessment to identify crucial assets for a resilient transportation system that supports multimodal transport, redundant routes, and emergency response. Based on input from the working group, the assessment focused on transportation assets falling into the following categories: • Bus routes • Key supporting services: bus and train maintenance centers and intermodal railyards • Goods movement connectors: connectivity between major trucking routes and businesses • Access points for transportation-disadvantaged, rural populations • Access to transit for transportation-disadvantaged, urban populations • Evacuation routes operating at low level of service • Air and deep-water transport: Stockton Airport and Port of Stockton The study team investigated how these assets are projected to be impacted by each climate stressor. This included an assessment of which assets will be exposed to the impact, sensitivity of assets to the impact, how easily assets can adapt, and the consequences of a disruption to the community. The working group identified the following assets as priorities for adaptation planning: Top Priorities Additional Priorities • SR-99 through Lodi • Port of Stockton • South Stockton Neighborhood • I-5 between Tracy & Lathrop • Stockton Airport • Waterloo Rd/CA-88 • Stockton Wye • Bus stops in downtown Stockton, Hammer • SR-4 from Stockton west to Contra Costa Triangle, Harrell Park • BNSF Intermodal Railyard After investigating these vulnerabilities as well as existing hazards and transportation planning, the study team identified the following system-wide adaptation needs: • Strategies for a resilient transit system • Requirements to integrate resilient designs into road and infrastructure upgrade projects • Plans to adapt to Public Safety Power Shutoffs (as a precaution to avoid wildfires) Findings and recommendations from this study will drive development of tools and actions to support local and regional adaptation efforts. 4 Climate Adaptation Report March 2020 Introduction The San Joaquin Council of Governments (SJCOG) Climate Adaptation and Resiliency Study is a year- long effort, launched in March of 2019, to consider how to improve the resiliency and increase the reliability of the transportation system in the face of climate impacts. Serving as the drainage basin for the San Joaquin River and its many tributaries, San Joaquin County is projected to face increased flood risk over time. The frequency and size of extreme precipitation events are expected to increase, and rising sea levels are predicted to move up into the delta. The intensity and frequency of droughts and heat waves are also anticipated to increase. While climate projections indicate that extreme fire events may remain steady or decline slightly in San Joaquin County through the mid-century, wildfire projections continue to evolve, and fire risk remains an important issue.1 Recognizing that climate hazards may cause far-reaching impacts to the communities, economy, and environment of San Joaquin County, SJCOG undertook a study to assess climate impacts. The purpose of this study is to examine how climate will impact a highly networked component of the county’s infrastructure—the transportation system. Some examples of the types of impacts that the study team evaluated across the system are provided in Table 1. This study considers existing climate impact planning efforts in order to identify where additional adaptation planning and actions are needed. Given SJCOG’s responsibility for producing the Regional Transportation Plan (RTP) for the region every four years, the study team also looked for opportunities to further integrate resiliency into transportation project prioritization and design. 1 Westerling, Anthony Leroy. (University of California, Merced). 2018. Wildfire Simulations for California’s Fourth Climate Change Assessment: Projecting Changes in Extreme Wildfire Events with a Warming Climate. California’s Fourth Climate Change Assessment, California Energy Commission. Publication Number: CCCA4-CEC-2018- 014. 5 Climate Adaptation Report March 2020 Table 1. Impacts of climate stressors on transportation assets.2 Flooding (riverine, Extreme Extreme Wildfire Drought precipitation, sea level rise) Temperature Roads Asphalt stripping, washouts, Asphalt-concrete Rutting/softening, Shrinking of subbase erosion, route cracking closures, need