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September 10, 2021
Surface Transportation and Climate Change: Provisions in the
Senate-Passed Infrastructure Investment and Jobs Act
Surface transportation is a major source of carbon dioxide
gallon in Japan, $3.93 in the United Kingdom, and $4.27 in
in the atmosphere, one of the main greenhouse gases
Italy. Federal taxes on gasoline and diesel in the United
(GHGs) contributing to climate change. At the same time,
States have been collected largely to raise funds for
the effects of climate change, such as extreme heat and sea
infrastructure construction, not to control GHG emissions.
level rise, pose a threat to highways, bridges, and public
They are typically extended and sometimes raised in
transportation infrastructure. The House and Senate both
surface transportation authorizing legislation.
have taken reauthorization of surface transportation
programs as an opportunity to propose policies and
Figure 1. U.S. Greenhouse Gas Emissions by
programs that address climate change. The current
Economic Sector, 2000-2019
authorization of federal highway, public transportation, and
intercity passenger rail programs in the Fixing America’s
Surface Transportation (FAST) Act (P.L. 114-94), as
extended, expires on September 30, 2021.
In August 2021, the Senate passed an amendment in the
nature of a substitute to the House-passed H.R. 3684. The
Senate-passed bill is known as the Infrastructure Investment
and Jobs Act (IIJA). The IIJA includes mitigation policies
and programs that aim to reduce GHG emissions from
surface transportation and adaptation policies and programs
that aim to make the surface transportation system more
Source: Environmental Protection Agency, Inventory of U.S.
resilient to the impacts of actual or expected future climate
Greenhouse Gas Emissions and Sinks: 1990-2019, table 2-10, at
change and to reduce its vulnerability to the harmful effects
https://www.epa.gov/ghgemissions/inventory-us-greenhouse-gas-
of future climate change.
emissions-and-sinks-1990-2019.
Transportation and GHG Emissions
Several other current federal policies that address GHG
The U.S. Environmental Protection Agency (EPA)
emissions from transportation are not typically addressed in
estimates that since 2017, transportation has emitted more
surface transportation reauthorization legislation. This
GHGs than any other sector of the U.S. economy. In 2019,
includes the regulation of vehicle fuel economy by the
transportation accounted for approximately 29% of the total
Corporate Average Fuel Economy standards administered
(Figure 1). Total GHG emissions from transportation were
by the National Highway Traffic Safety Administration
about 5% less in 2019 than in 2005, but increased each year
and, by extension, the GHG standards, administered by
from a recent low in 2012 through 2018, in part because of
EPA. These policies, along with tax incentives and grants
increased passenger travel and goods movement; the effects
for the domestic development and manufacture of
of greater vehicle mileage have been somewhat mitigated
alternative fueled vehicles, are typically dealt with in
by improvements in fuel efficiency. There was a slight
energy bills rather than in transportation legislation. One
reduction in transportation emissions in 2019, but a larger
exception is the designation of alternative fuel corridors, a
drop is expected in reports for 2020 due in part to the
FAST Act provision, which may be the basis for a national
disruptions related to the COVID-19 pandemic.
network of alternative fueling and charging infrastructure.
Mitigating GHG Emissions from
Surface Transportation
Surface transportation programs do in some respects
encourage the deployment of alternative fueled vehicles and
Economists generally agree that broad, market-based
a reduction of vehicle miles traveled. The Federal Transit
policies, such as a cap and trade system or carbon tax, are
Administration (FTA) program that provides funding for
likely to be the most efficient way to reduce GHG
buses includes a set-aside for buses that are alternatively
emissions across all economic sectors. Motor vehicle fuel
fueled, and the Federal Highway Administration (FHWA)
taxes might be considered a crude form of carbon tax in
administers the Congestion Mitigation and Air Quality
surface transportation, and the comparatively higher fuel
Improvement (CMAQ) program. The original motivation
taxes in other countries are associated with lower annual
for these programs was to meet air quality goals, but such
mileage per person and greater use of more fuel-efficient
policies may help reduce GHGs from surface
vehicles. In 2019, the average of U.S. state taxes weighted
transportation.
by fuel volume combined with the federal tax on a gallon of
gasoline was 48 cents. The equivalent tax was $2.48 per
https://crsreports.congress.gov
Surface Transportation and Climate Change: Provisions in the Senate-Passed Infrastructure Investment and Jobs Act
Adaptation to Climate Change in
transportation would increase from $12.6 billion in FY2021
Surface Transportation
to $16.5 billion in FY2022, then rise every year to $17.8
Impacts from actual or expected future climate change are
billion in FY2026. In addition to providing the funding
likely to include higher average temperatures, greater
authorizations, the IIJA would appropriate $4.3 billion
extremes of temperature, more precipitation overall with an
annually for public transportation for FY2022-FY2026. The
increase in precipitation intensity and greater variation, and
authorization for Amtrak and other intercity rail programs
a rise in sea level. While the consequences of some of these
would increase from $2.5 billion in FY2021 to $7.2 billion
changes may depend to some extent on other human
in FY2022. After decreasing in FY2023 to $6.7 billion, the
activities, such as urban development patterns, they are
authorization would then rise every year to $7.8 billion in
likely to include more frequent periods of extreme heat;
FY2026. In addition, the IIJA would appropriate $13.2
fewer days below freezing; more coastal, riverine, and flash
billion annually for intercity rail for FY2022-FY2026.
flooding; and more droughts and wildfires. Intense
precipitation could lead to more mudslides, particularly
The IIJA also would authorize an increase in funding for
following droughts and wildfires.
the federal-aid highway program from $47.3 billion in
FY2021 to $60.9 billion in FY2022, then rise every year to
Existing surface transportation infrastructure can be
$66.6 billion in FY2026. Although this may result in more
vulnerable to climate change because it was constructed for
highway vehicle travel and GHG emissions, the funding
sea level and weather extremes that are being or are likely
includes increases for existing highway programs aimed at
to be exceeded in the future. If the effects of climate change
emissions reductions as well as new programs. For
become more pronounced, as studies anticipate, the impacts
example, funding from the Highway Trust Fund (HTF) for
of extreme weather on surface transportation infrastructure
the existing Transportation Alternatives Program would
and operations are likely to increase in magnitude, duration,
increase from $850 million in FY2021 to $1.4 billion in
and frequency. For example, an increase in the number of
FY2022. New mitigation programs and the average annual
very hot days could cause more damage to bridges because
authorization from the HTF for FY2022 through FY2026
of greater thermal expansion of bridge joints.
are:
“Adaptation” is action to reduce the vulnerabilities and
Carbon Reduction Program: $1.3 billion
increase the resilience of the transportation system to the
Charging & Refueling Grant Program: $500 million
effects of climate change. Adaptation and resilience options
include structural and nature-based engineering and policy-
Reduce Truck Emissions at Port Facilities: $50 million
based activities. For example, highway bridges can be
engineered structurally to withstand the threats of higher
Congestion Relief Program: $50 million.
wind and water. Nature-based engineering may involve
reducing climate vulnerabilities through activities such as
New programs and the average annual appropriation from
wetland restoration, artificial reef construction, and beach
the Treasury general fund for FY2022 through FY2026 are:
restoration. Policy-based activities include changing
maintenance practices, such as more frequent drain
Electric Vehicle Charging Formula Program: $1 billion
cleaning, and improving plans for weather emergencies.
Reduce Truck Emissions at Port Facilities: $30 million.
Currently, there is no dedicated surface transportation
Adaptation and Resilience
funding for adaptation and resilience projects. FHWA has
The IIJA would make several changes to the federal
stated that federal highway funds can be used to assess the
highway program aimed at improving adaptation and
potential impacts of climate change and to apply adaptation
resilience. It would add definitions of “resilience” and
strategies. Likewise, federal transit funding administered by
“natural infrastructure” to Title 23 of the U.S. Code. It
FTA can be used for adaptation projects. Several aspects of
would specifically allow federal funding to be used for
federal law, regulation, and policy require state and local
“protective features” designed to mitigate the risk of
agencies that manage surface transportation assets to
recurring damage from extreme weather events, flooding,
consider the effects of climate change.
or other natural disasters. The IIJA would also allow up to
Infrastructure Investment and Jobs Act
15% of the annual apportionment of National Highway
Performance Program funding to be used for resilience
The IIJA would make several changes to existing law and
features for highways or bridges that are not part of the
surface transportation funding programs in relation to GHG
National Highway System.
mitigation and surface transportation infrastructure
adaptation and resilience.
The IIJA also would establish the Promoting Resilient
Operations for Transformative, Efficient, and Cost-saving
Mitigation
Transportation (PROTECT) Program to support adaptation
The IIJA would authorize increases in funding for public
and resilience projects. Funding from the HTF would be
transportation and intercity passenger rail. Some advocates
authorized at an annual average of $280 million.
of these provisions assert that this funding would mitigate
climate change. This assumes that greater spending will
William J. Mallett, Specialist in Transportation Policy
boost rail and bus travel, replacing trips by private motor
vehicles and airplanes—something that has been difficult to
IF11921
achieve in the past. The authorization for public
https://crsreports.congress.gov
Surface Transportation and Climate Change: Provisions in the Senate-Passed Infrastructure Investment and Jobs Act
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https://crsreports.congress.gov | IF11921 · VERSION 1 · NEW