Impacts of Climate Change on the
Transportation Sector: Design and
Operations Implications
Michael D. Meyer, P.E., F. ASCE
F.R. Dickerson Professor
School of Civil and Environmental Engineering
Georgia Institute of Technology
Extent of Nation’s Transportation Infrastructure
Highways (public)
Transit stations
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• 1,153 commuter rail
• 1,023 heavy rail
• 723 light rail
46,873 miles of Interstate highway
115,500 miles NHS roads
3,849,259 miles of other roads
580,000 bridges
Airports
Navigable channels
• 5,270 public use airports
• 26,000 miles
Rail
Commercial waterway facilities
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95,664 Class 1 miles
15,388 regional miles
29,197 local miles
23,000 Amtrak miles
Great Lakes (600 deep/150 shallow draft)
2,320 Inland shallow draft
4,298 ocean deep/1,761 shallow draft
257 locks
Transit (directional miles)
Pipeline
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165,854 bus miles
4,407 commuter rail
1,596 heavy rail
1,097 light rail
60,043 miles crude
71,310 miles product
298,000 miles transmission
1,139,800 miles distribution
60,000 miles in FEMA coastal flood zone; 36,000
bridges within 15 nautical miles of coasts
Gulf Coast Study
Freight Rail Lines Vulnerable to Storm Surge of 18 feet
Transportation infrastructure that is vulnerable
to 18 feet of storm surge includes:
• 51% of interstate miles, 56% of arterial miles, and
most transit authorities
• 98% of port facilities vulnerable to surge and
100% to wind
• 33% of rail miles operated, 43% of freight facilities,
• 22 airports in the study area at or below 18 feet MSL
• Potentially significant damage to offshore facilities
Fundamental to the application of
engineering design standards is an
understanding of how environmental
factors and conditions will affect both
the behavior of the overall structure
itself as well as of the individual
material components of the design.
A Typical Infrastructure Segment
Typical Cross Sections
Subsurface
Structures
Drainage
Materials
Foundations
Figure 1: Critical Components of Infrastructure Design
Critical Components of
Infrastructure Design
1.
2.
3.
4.
5.
6.
Subsurface conditions
Materials specifications
Cross sections/standard dimensions
Drainage and erosion
Structures
Location engineering
Water, for example, ……..
Suggested Minimum Design Storm Frequency and Spread.
“The intensity of rainfall events may significantly affect the selection of design
frequency and spread.” FHWA, Urban Drainage Design Manual, 2001.
Road Classification
Design
Frequency
Design Spread
High Volume or < 70 km/hr (45 mph)
10-year
Shoulder + 1 m (3 ft)
Divided or Bi- > 70 km/hr (45 mph)
10-year
Shoulder
Directional Sag Point
50-year
Shoulder + 1 m (3 ft)
< 70 km/hr (45 mph)
10-year
1/2 Driving Lane +
Collector > 70 km/hr (45 mph)
10-year
Shoulder
Sag Point
10-year
1/2 Driving Lane
Low ADT
5-year
1/2 Driving Lane
Local Streets
10-year
1/2 Driving Lane
High ADT Sag Point
10-year
1/2 Driving Lane
Temperature, for example, ……..
“Two climatic factors, temperature and moisture, are
considered to influence the structural behavior of
the pavement.”
“With respect to subgrade strain and fatigue of
cement- and limestabilized base or subbase
courses, the design air temperature is the average
of two temperatures: (1) the average daily mean
temperature and (2) the average daily maximum
temperature during the traffic period.”
Temperature, for example, ……..
“Because of the extreme sensitivity of critical
stresses in rigid pavements to temperature
gradients, consideration of hourly variation in
temperature conditions is necessary.”
Corridor Impacts
Primary Climatic Changes
Increase in average temperatures
Increase in maximum temperatures
Increase in winter rainfall
Reduction in summer rainfall
More extreme rainfall events
Reduction in snowfall
Increased wind speed for worst gales
Sea level rise
Secondary Climatic Change Impacts
Longer growing season
Reduction in soil moisture
Change in groundwater level
Flooding
Reduction in fog days in winter
Reduction in icy days in winter
Frequency of extreme storm surges
Environmental
Factor
Facility
Possible Effect
Cause
Formula #
Saturation
Roadway
foundation
Rainfall
intensity
/frequency
increase
Roadway
pavement
Roadside slopes
Roadside planting
Bridge- water
crossing
Foundation
weakening
Erosion
Foundation and
roadway loss
Flooded culvert or
bridge failure
Surface
deterioration
Base and sub-base
saturation
403, 404,
405, 406
Surface loss
Flooded culvert failure
100-106
Erosion
302
Soil saturation
302
Groundwater elevation
increase
300, 301
Slope failure
Species growth
Structural damage
Hydration
Scour
100-106
Water load
202
Soils pressure change
Keller, Jake A.; Armstrong, Amit; Flood, Michael; Meyer, Michael D., AN APPROACH TO ADDRESSING THE IMPACTS OF CLIMATE
VARIABILITY ON ROADWAY AND BRIDGE DESIGN, Paper presented at the Annual Meeting of the Transportation Research Board,
Jan. 2011.
Environmental
Factor
Facility
Bridge—Roadway
crossing
Possible Effect
Cause
Structural damage
Soils pressure
change
Erosion
Structural damage
Culvert
Rainfall
intensity
/frequency
increase
Formula #
Failure
Erosion
Floodwater erosion
Buoyancy
Storm sewer
Surcharge
High runoff rate
100
High runoff rate
100-108
Soil saturation
302
Failure
Erosion from high
runoff rate and/or
volume
101-108
Stream mitigation
Erosion from high
runoff rate and/or
volume
100-108
Flooding
Open channel
Similar information for rainfall decrease…..
Environmental
Factor
Facility
Possible Effect
Cause
Roadway
foundation
401, 407
Asphalt strength
decrease
Loss of viscosity
404, 406
Concrete pavement
heaving
Thermal expansion
406, 407
Species death or
migration
Erosion
302
Soil saturation
302
Bridge- water
crossing
Structural damage
Thermal expansion
200
Bridge—roadway
crossing
Structural damage
Thermal expansion
200
Flooding
Snowmelt
Roadway
pavement
Roadside planting
Temperature
Rise
Formula #
Culvert
Storm sewer
Open channel
Keller, Jake A.; Armstrong, Amit; Flood, Michael; Meyer, Michael D., AN APPROACH TO ADDRESSING THE IMPACTS OF CLIMATE
VARIABILITY ON ROADWAY AND BRIDGE DESIGN, Paper presented at the Annual Meeting of the Transportation Research Board,
Jan. 2011.
Environmental
Factor
Temperature
Fall
Facility
Possible Effect
Roadway
foundation
Foundation
weakening
Roadway
pavement
Pavement base and
surface failure
Roadside slopes
Slope stability
decrease
Roadside planting
Species death or
migration
Bridge- water
crossing
Structural damage
Bridge—roadway
crossing
Culvert
Storm sewer
Open channel
Cause
Formula #
401,403,404
405, 406
Freeze/thaw cycle
frequency increase
401, 407
Ice load
201
Thermal contraction
200
Foundation
weakening
Thermal contraction
200
Structural damage
Ice load
Ice blockage
Capacity reduction
Icing
406, 407
100-108
100
100-108
Keller, Jake A.; Armstrong, Amit; Flood, Michael; Meyer, Michael D., AN APPROACH TO ADDRESSING THE IMPACTS OF CLIMATE
VARIABILITY ON ROADWAY AND BRIDGE DESIGN, Paper presented at the Annual Meeting of the Transportation Research Board,
Jan. 2011.
Environmental
Factor
Facility
Possible Effect
Cause
Saturation
Roadway
foundation
Foundation
weakening
Foundation and
roadway loss
Roadside
slopes
Rise in Sea
Level
Bridge- water
crossing
Slope failure
Structural damage
Storm sewer
300, 301
Erosion form wave action
Groundwater elevation
increase
300, 301
Flooded culvert or bridge
failure
300, 301
Erosion
302
Soil saturation
302
Scour
102
Water load
202
Soils pressure change
Culvert
Formula #
Structural damage
Erosion
Failure
Floodwater erosion
Surcharge
Higher tailwater
Flooding
Higher tailwater
Failure
Erosion at higher elevations
Open channel
Environmental
Factor
Wind force
increase
Facility
Possible Effect
Cause
Formula #
Roadside
slopes
Material loss
Wind erosion
Bridge- water
crossing
Structural damage
Wind load, increased water
borne debris load
203, 204
Bridge-road
crossing
Structural damage
Wind load
203, 204
Culvert
Capacity
reduction or
structural damage
Wind load, increased
waterborne debris load
Open channel
Material loss
Wind erosion
Representative Design Formulae and Possible Effects: Hydrology
Keller, Jake A.; Armstrong, Amit; Flood, Michael; Meyer, Michael D., AN APPROACH TO
ADDRESSING THE IMPACTS OF CLIMATE VARIABILITY ON ROADWAY AND BRIDGE DESIGN
Keller, Jake A.; Armstrong, Amit; Flood, Michael; Meyer, Michael D., AN APPROACH TO
ADDRESSING THE IMPACTS OF CLIMATE VARIABILITY ON ROADWAY AND BRIDGE DESIGN
Federal Highway Administration
“In the coastal environment, design practices
assume that flood events would essentially
behave in a manner similar to a riverine
environment, which assumes a 50-year
storm event…result is that designs do not
consider the effect of wave actions on the
bridge.”
“State DOTs find themselves in the position
that their own regulations and guidelines do
not permit them to consider alternative
bridge design criteria.”
Recommendation: 100-year design storm
that considers wave and surge effects as
well as the likelihood of pressure scour.”
Proactive Strategies to Flood Risk
Preventing flooding by improving the rainfall
capture and storage capacity of a catchment (e.g.
by enhancing or mimicking the water storage
capacity of the soil);
Increasing conveyance capacity to disperse
floodwaters;
Creating policies to maintain existing levels of
service which incorporate climate change factors
at the time of repairs or upgrades;
NZ Transport Agency, Climate Change Effects on the Land Transport Network,
Volume Two: Approach to Risk Management, 2009
Establishing physical protection measures, e.g.
building stop-banks;
Managing the effects of flooding by removing atrisk land use such as infrastructure and the built
environment in floodplains; and
Managing the expectations of communities in
flood-prone areas to expect and cope with flood
events.
NZ Transport Agency, Climate Change Effects on the Land Transport Network,
Volume Two: Approach to Risk Management, 2009
NCHRP 20-83(5)
Climate Change and the Highway System:
Impacts and Adaptation Approaches
Climate Adaptation
Planning
Identify critical
performance measures
Identify critical assets in
the network
Identify predominant
climate change trends
and factors for region
Identify impact of
these changes on local
environmental
conditions
Apply
triggers
Identify affected
highway agency
functions
Network
Functions
Asset X
Assess feasibility and cost effectiveness
of adaptation strategies
Asset C
Change design standards
Change operating strategies
Change maintenance practices
Change construction practices
Etc.
Identify
trigger
levels
Asset B
Conduct risk
appraisal of
vulnerabilities and
environmental
changes
Asset A
Identify
vulnerabilities of
highway system to
these changing
conditions
Michigan DOT
More Intense Storms – Strategy: Design
assets that are less impacted by affects of
Climate Change
• Larger hydraulic openings for bridges over
waterways
• Heavier and lengthier armoring of river and
stream banks and ditches to prevent erosion
• Investigate greater pavement crowns to
move runoff off of pavement quicker
• Design of additional insystem detention to meter
runoff outflow
• Eliminate bridge design
elements that could make
a bridge scour critical
– i.e. piers in the river,
spread footings, use
more sheet piling left in
place
• Design terraced
vegetated slopes using a
variety of plant species
• Design more robust pavement markings
that can be seen during wet/night
conditions
• Larger capacity pumps/pump stations for
below grade freeways to prevent flooding
So…
• As primarily an “application” field, we rely
on information produced by many of you
• Temporal and spatial scale issues
• “It all depends…” approach to design…for
different components of a typical design
• We are learning now about extreme
events that are exceeding our design
capacities, and what this means for future
approaches….infrastructure with different
useful lives
• Better approaches for incorporating
uncertainty are needed … risk analysis
• Multiple strategy types: avoid, relocate,
abandon, protect, etc.
• Growing interest in how we think about
infrastructure vulnerability and plan for
adaptation…and quite frankly we are
waiting for approaches and methods
based on good science for developing
usable information and data
Climate Adaptation
Planning
Identify critical
performance measures
Identify critical assets in
the network
Identify predominant
climate change trends
and factors for region
Identify impact of
these changes on local
environmental
conditions
Apply
triggers
Identify affected
highway agency
functions
Network
Functions
Asset X
Assess feasibility and cost effectiveness
of adaptation strategies
Asset C
Change design standards
Change operating strategies
Change maintenance practices
Change construction practices
Etc.
Identify
trigger
levels
Asset B
Conduct risk
appraisal of
vulnerabilities and
environmental
changes
Asset A
Identify
vulnerabilities of
highway system to
these changing
conditions