Where are We Vulnerable?

Battenfeld Road in Milan, Hurricane Irene

Assessing Our Vulnerability

Resilient Ways Forward includes a countywide evaluation of how our transportation system is vulnerable to climate change. The scope of our system lends itself to a two-phased approach: a system-level analysis that measures risks, and a subsequent asset-level analysis that identifies priorities.


Phase 1: System-Level Analysis

The system-level analysis helps us understand the relative risk of our transportation assets to several climate hazards: extreme heat, flooding, drought, wind, winter conditions, and landslides. We measured this risk on a scale of low, medium, or high for each asset type, focusing on the sensitivity of both infrastructure (e.g., bridges) and services (e.g., bus routes) to hazards. Assets with the highest risk moved on to the Phase 2 asset–level analysis.

What are our transportation assets?

  • Roads
  • Bridges
  • Culverts
  • Rail lines/ stations
  • Bus system
  • Sidewalks
  • Rail trails
  • Regional airport
  • Highway garages
  • Park & Rides
  • Transit hub
  • Beacon ferry dock


Phase 2: Asset-Level Analysis

This asset-level analysis uses a range of indicators to help us identify priorities for adaptation. We focused on the highest-ranking transportation asset and climate hazard combinations from the system-level analysis and looked at their ‘exposure’ and ‘criticality’ (see graphic). We then assigned a vulnerability index rating to each asset or service. These ratings shape our recommendations and priorities, which we share in What Can We Do?

Equity & Transportation Resilience

Transportation is essential for accessing healthcare, education, employment, and basic services. Underserved populations tend to have limited transportation options, and when climate related events occur, their ability to access these services can be further compromised. Investing in transportation resilience ensures that these communities, and their access to basic needs, are prioritized.

  • Depth of flooding
  • Proximity to steep slopes
  • Location in an urban heat island 
  • Historical incidence of impacts
  • Transportation Equity Scores
  • Proximity to key destinations
  • Average annual daily traffic
  • Detour length (if available)