Surface Transportation and Climate Change: Provisions in the Infrastructure Investment and Jobs Act (P.L. 117-58)

Updated March 4, 2022

Surface Transportation and Climate Change: Provisions in the

Infrastructure Investment and Jobs Act (P.L. 117-58)

Surface transportation is a major source of carbon dioxide

in the atmosphere, one of the main greenhouse gases

(GHGs) contributing to climate change. The effects of

climate change, such as extreme heat and sea level rise, also

pose a threat to highways, bridges, and public transportation

infrastructure. Congress reauthorized the surface

transportation programs as part of the Infrastructure

Investment and Jobs Act (IIJA; P.L. 117-58). The IIJA

included mitigation policies and programs aiming to reduce

GHG emissions from surface transportation and adaptation

policies and programs aiming to make the surface

transportation system less vulnerable and more resilient to

the impacts of actual or expected future climate change. As

with previous authorization acts, the IIJA funded surface

transportation programs from the Highway Trust Fund

(HTF). The IIJA also provided funding with a multiyear

advance appropriation from the Treasury general fund.

Transportation and GHG Emissions

The U.S. Environmental Protection Agency (EPA)

estimates that since 2017, transportation has emitted more

GHGs than any other sector of the U.S. economy. In 2019,

prior to the Coronavirus Disease 2019 (COVID-19)

pandemic, transportation accounted for approximately 29%

of the total (Figure 1). Total GHG emissions from

transportation were about 5% less in 2019 than in 2005, but

increased each year from a recent low in 2012 through

2018, in part because of increased passenger travel and

goods movement; the effects of greater vehicle mileage

have been somewhat mitigated by improvements in fuel

efficiency. There was a slight reduction in transportation

emissions in 2019, but a 14% drop in 2020 due largely to

disruptions caused by the pandemic.

Mitigating GHG Emissions from

Surface Transportation

Economists generally agree that broad, market-based

policies, such as a cap and trade system or carbon tax, are

likely to be the most efficient way to reduce GHG

emissions across all economic sectors. Motor vehicle fuel

taxes might be considered a crude form of carbon tax in

surface transportation, and the higher fuel taxes in other

countries are associated with lower annual mileage per

person and greater use of more fuel-efficient vehicles. In

2020, the average of U.S. state taxes weighted by fuel

volume plus the federal tax on a gallon of gasoline was

$0.48. This compared with per-gallon taxes of $2.59 in

Japan, $3.65 in the United Kingdom, and $4.57 in Italy.

Federal taxes on gasoline and diesel in the United States

have been collected largely to raise funds for infrastructure

construction, not to control GHG emissions. The IIJA

extended through FY2028 the collection of the fuels and

other taxes that accrue to the HTF.

Figure 1. U.S. Greenhouse Gas Emissions by

Economic Sector, 2000-2020

Source: EPA, Draft Inventory of U.S. Greenhouse Gas Emissions and

Sinks: 1990-2020, table 2-10.

Several other current federal policies that seek to reduce

GHG emissions from transportation are not typically

addressed in surface transportation reauthorization

legislation, including the IIJA. This includes the regulation

of vehicle fuel economy by the Corporate Average Fuel

Economy standards administered by the National Highway

Traffic Safety Administration and, by extension, the GHG

standards, administered by EPA. These policies, along with

tax incentives and grants for the domestic development and

manufacture of alternative fueled vehicles, are typically

dealt with in energy bills rather than in transportation

legislation. Nevertheless, the IIJA contained energy

provisions, including funding for a Clean School Bus

Program administered by EPA. For more details, see CRS

Report R47034, Energy and Minerals Provisions in the

Infrastructure Investment and Jobs Act (P.L. 117-58),

coordinated by Brent D. Yacobucci.

Surface transportation programs reauthorized in the IIJA do

in some respects encourage the deployment of alternativefueled vehicles and a reduction of vehicle miles traveled.

The Federal Transit Administration (FTA) Low and No

Emission Vehicle program provides funding for

alternatively fueled buses, and the Federal Highway

Administration (FHWA) administers the Congestion

Mitigation and Air Quality Improvement (CMAQ)

program. The original motivation for these programs was to

meet air quality goals, but such policies may help reduce

GHGs from surface transportation.

Adaptation to Climate Change in

Surface Transportation

Impacts from actual or expected future climate change are

likely to include higher average temperatures, greater

extremes of temperature, more precipitation overall with an

increase in precipitation intensity and greater variation, and

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Surface Transportation and Climate Change: Provisions in the Infrastructure Investment and Jobs Act (P.L. 117-58)

a rise in sea level. While the consequences of some of these

changes may depend to some extent on other human

activities, such as urban development patterns, they are

likely to include more frequent periods of extreme heat;

fewer days below freezing; more coastal, riverine, and flash

flooding; and more droughts and wildfires. Intense

precipitation could lead to more mudslides, particularly

following droughts and wildfires.

Existing surface transportation infrastructure can be

vulnerable to climate change because it was constructed for

sea level and weather extremes that are being or are likely

to be exceeded in the future. If the effects of climate change

become more pronounced, as studies anticipate, the impacts

of extreme weather on surface transportation infrastructure

and operations are likely to increase in magnitude, duration,

and frequency. For example, an increase in the number of

very hot days could cause more damage to bridges because

of greater thermal expansion of bridge joints.

“Adaptation” is action to reduce the vulnerabilities and

increase the resilience of the transportation system to the

effects of climate change. Adaptation and resilience options

include structural and nature-based engineering and policybased activities. For example, highway bridges can be

engineered structurally to withstand the threats of higher

wind and water. Nature-based engineering may involve

reducing climate vulnerabilities through activities such as

wetland restoration, artificial reef construction, and beach

restoration. Policy-based activities include changing

maintenance practices, such as more frequent drain

cleaning, and improving plans for weather emergencies.

Prior to the IIJA, FHWA had stated that federal highway

funds could be used to assess the potential impacts of

climate change and to apply adaptation strategies. Likewise,

federal transit funding administered by FTA could be used

for adaptation projects. Several aspects of federal law,

regulation, and policy required state and local agencies that

manage surface transportation assets to consider the effects

of climate change.

Infrastructure Investment and Jobs Act

The IIJA made several changes to law and surface

transportation funding programs for mitigation and surface

transportation infrastructure adaptation and resilience.

Mitigation

The IIJA authorized and appropriated increases in funding

for public transportation and intercity passenger rail. Some

advocates of these provisions assert that this funding could

mitigate climate change. This assumes that greater spending

will boost rail and bus travel, replacing trips by private

motor vehicles and airplanes—something that has been

difficult to achieve in the past. Excluding COVID-19 relief

and other emergency funding, public transportation

program funding was $13.0 billion annually in FY2021,

whereas the amount authorized and appropriated in the IIJA

was $21.4 billion annually for FY2022-FY2026 (unadjusted

for inflation). The Treasury general fund authorization for

Amtrak and other intercity rail programs, subject to

appropriation, increased from $2.5 billion in FY2021 to an

average of $7.2 billion annually for FY2022-FY2026. In

addition, the IIJA appropriated $13.2 billion annually for

intercity rail programs for FY2022-FY2026.

The IIJA also authorized and appropriated an increase in

funding for the federal highway program from $47.3 billion

in FY2021 to an annual average of $73.1 billion for

FY2022-FY2026. This may result in more highway vehicle

travel and GHG emissions, but the funding included

increases for new and existing highway programs aimed at

emissions reductions. For example, funding from the HTF

for the existing Transportation Alternatives Program

increased from $850 million in FY2021 to an annual

average of $1.4 billion for FY2022-FY2026. New

mitigation programs and the average annual authorization

in the IIJA from the HTF for FY2022-FY2026 were:

 Carbon Reduction Program: $1.3 billion

 Charging & Refueling Grant Program: $500 million

 Reduce Truck Emissions at Port Facilities: $50 million

 Congestion Relief Program: $50 million.

New programs and the average annual appropriation from

the Treasury general fund for FY2022-FY2026 in the IIJA

were:

 Electric Vehicle Charging Formula Program: $1 billion

 Reduce Truck Emissions at Port Facilities: $30 million.

Adaptation and Resilience

The IIJA made several changes to the federal highway

program aimed at improving adaptation and resilience. It

added definitions of “resilience” and “natural

infrastructure” to Title 23 of the U.S. Code. It specifically

allowed federal funding to be used for “protective features”

designed to mitigate the risk of recurring damage from

extreme weather events, flooding, or other natural disasters.

The IIJA also allowed states to use up to 15% of their

annual apportionment of National Highway Performance

Program funding for resilience features for highways or

bridges that are not part of the National Highway System.

The IIJA also established the Promoting Resilient

Operations for Transformative, Efficient, and Cost-saving

Transportation (PROTECT) Program to support adaptation

and resilience projects. Funding from the HTF was

authorized at an annual average of $1.7 billion.

The IIJA also authorized Treasury general funds for some

new programs, subject to appropriations. This included

$100 million annually for Transportation Resilience and

Adaptation Centers of Excellence, $100 million annually

for the Healthy Streets Program, and $200 million annually

for the Active Transportation Infrastructure Investment

Program. Healthy Streets Program grants would be to

construct pavement that reflects sunlight, to construct

pavement porous to rainwater, and to expand tree cover.

William J. Mallett, Specialist in Transportation Policy

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IF11921

Surface Transportation and Climate Change: Provisions in the Infrastructure Investment and Jobs Act (P.L. 117-58)

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