Pilot Study Finds Shoreline and Transportation Infrastructure in Alameda County Vulnerable to Sea-Level Rise
Some of the Bay Area’s most important transportation infrastructure is vulnerable and at risk to global warming induced sea-level rise, according to a recent multi-agency pilot study. The study, which focused on the Alameda County shoreline between Emeryville and Union City, found that the Posey and Webster tubes connecting Oakland to Alameda, BART’s Transbay Tube between Oakland and San Francisco, and the eastern approach to the Bay Bridge in Oakland are all at risk.
The pilot study, “Adapting to Rising Tides: Transportation Vulnerability and Risk Assessment,” by the Metropolitan Transportation Commission (MTC), Caltrans, and the Bay Conservation and Development Commission (BCDC), with assistance from AECOM and Arcadis, gives new urgency to efforts to further assess the vulnerability of transportation infrastructure to sea-level rise and to begin a rigorous adaptation planning effort to respond sea-level rise in the Bay Area. It was completed with funding from the Federal Highway Administration.
“The San Francisco Bay is one of the most economically and ecologically vibrant regions in the world,” said BCDC’s former executive director Will Travis in his introduction to the report. “But it is also critically vulnerable to the impacts of climate change. As a region, it is imperative that we adapt to the impacts of climate change by fostering resilient and sustainable development. This challenge brings us an exciting opportunity to embrace a spirit of stewardship that advances both economic and environmental prosperity.”
“Adapting to Rising Tides” assesses two scenarios assuming that climate change will cause the Bay to rise 16 inches by 2050 and 55 inches by the end of the century. That means that today’s highest floods will be the future’s daily high tides and areas that currently flood every 10–20 years will flood much more frequently. Neighborhoods, businesses and entire industries that currently exist on the shoreline will be subject to this flooding and the many other direct impacts that will result from it. These areas are home to more than 250,000 residents who will be directly affected and many others, including workers, who will be indirectly affected by reduced access to important services, such as transit and commercial centers, health-care facilities and schools.
By assigning a risk level to each transportation structure – whether road, airport, bridge or tunnel – the agencies say they can prioritize decision making and policy development for future adaptation. In a parallel effort, BCDC looked at additional community assets other than transportation, such as parks and recreation, community land use, stormwater and wastewater, that may also be vulnerable. The study results will be used to inform adaptation planning efforts for all sectors within the project area.
Adaptation measures may range from broad-level adaptation planning that delves into policy, governance and financing issues to infrastructure solutions such as building levees, flood walls and expanded wetlands; relocating or temporarily closing a structure; or rerouting traffic. Other complementary strategies include new building codes, zoning requirements like setbacks or buffer zones, updating design guidance and providing education and community outreach to increase awareness and make communities more resilient.