addressing climate change adaptation in regional transportation plans

Addressing Climate Change Adaptation in Regional Transportation PlansA Guide for California MPOs and RTPAsWhen designing new infrastructure, there will be a need to switch fromdesigning with standards developed for historic climate trends to designing forfuture (and uncertain) climate projections – many elements of transportationinfrastructure are sufficiently long-lived that it may not be prudent to plan anddesign based on historic averages. Other possible changes to the design phaseinclude the need for a broader systems approach and risk managementprocedures to incorporate climate change into decision-making and definingappropriate design characteristics (Meyer, 2008). This long-range perspectiveneeds to be balanced with monitoring for near-term changes that may requiremore immediate design adjustments. For example in the flooding of San PedroCreek and coastal erosion at Pacific/Linda Mar State Beach has been a recurringproblem for the City of Pacifica 3 . In the 1990s, the city worked with a number ofstakeholders to work toward a managed retreat strategy to reduce flooding,erosion threats and restored wetland habitat to buffer the system against futuresea-level rise. This wetland project invested substantially more upfront in floodprotection including removing fill, relocating infrastructure and restoring beach.This provided long-term payback, including protection before flooding increasedfurther with the potential to affect Highway 1 (Kershner, 2010).In addition to the direct effects on transportation infrastructure and services,climate change will catalyze changes in the environmental, demographic, andeconomic conditions within which transportation agencies conduct their work.In the long run, these broader changes may have very significant secondaryimpacts on the transportation sector that will need to be examined as part of theplanning process. For example, changes in population centers induced by shiftsin weather conditions will affect travel demand. As regions of agriculturalproduction shift, freight flows may likewise change. The effect on roads andhighways from the secondary impacts of sea-level rise in the San Francisco BayArea is one example. Some cities such as Berkeley and Albany have shorelinesalong I-80 that are not directly subject to flooding due to the existing roadwayelevation; however, erosion from rising sea levels can undermine existingprotective structures that can increase the overall cost of highway maintenance(SFBCDC, 2009).3 http://www.cakex.org/case-studies/2834.Cambridge Systematics, Inc. 2-5