transportation systems, such as ports and the onroad and rail lines that service these facilities are currently vulnerable to coastal flooding- storm
surge, and damaging waves, and their exposure is expected to increase due to
climate variability and associated extreme events. Over 60,000 roadway miles
are within the Federal Emergency Management Agency’s 100-year floodplains
delineated in U.S. coastal counties. More than 36,000 bridges are located
within 15 miles of the coast, and over 1,000 of these bridges have simply
supported spans that are vulnerable to damage by storm surge and waves. As sea
levels rise, the risk of flooding or damage to this infrastructure is expected
to increase, and it is likely that the number of at-risk roadway miles will
increase as well.
Climate variability is
expected to impact transportation infrastructure in many ways, such as:
Sea level rise,
Variability of storm frequency and storm intensity,
Changes in precipitation patterns and amounts,
Changes in temperature, and
Uncertainty related to the frequency of extreme events.
Any of these can cause
transportation disruptions, damage to transportation infrastructure, and
increased long-term maintenance or replacement costs, including:
Vulnerability of ports and supporting
infrastructure to flooding and wave actions,
Disruption to the electrical grid,
Impacts to water quality and water
Changes to hydrodynamic regime and
To be better prepared for these impacts it is critical to identify the areas at risk and appreciate mitigation options that need to be in place prior to a sever weather event.
of U.S. roadway miles and bridges are currently exposed to coastal and riverine
flooding, and their vulnerability (i.e., risk, sensitivity, and adaptive
capacity) is expected to increase in light of climate variability and
associated extreme events. Studies such as the U.S. Department of
Transportation’s Gulf Coast Study Phase 2, the Post-Hurricane Sandy Transportation
Resilience Study of NY, NJ, and CT, and Green Infrastructure Techniques for
Resilience of the Oregon Coast Highway have described issues and challenges with
the exposure and sensitivity of intermodal transportation systems and critical
infrastructure expected and actual impacts of climate change.
To anticipate possible affects common characteristic of possible sever weather events need to be better understood such as the size and duration of
accompanying rains as well as wind speed.
For example, one of impact of Florence and Harvey is how the inland rains
produced flooding, that generated environmental threats downriver impacting
infrastructure in ports and coastal communities.
also provides information and tools applicable for other metropolitan planning
organizations to assess their vulnerability to climate change impacts.