Highway Bridges: Conditions, Funding
July 25, 2022
Programs, and Issues for Congress
Robert S. Kirk
The United States has approximately 620

Highway Bridges: Conditions, Funding Programs, and Issues for Congress

Updated April 20, 2026 (R47194) Jump to Main Text of Report

Contents

• Introduction
• Bridge Characteristics
• Bridge Inspection
• Bridge Conditions
• Bridge Vulnerabilities to Extreme Events
• Bridge Infrastructure Funding
• Federal and State Roles
• Congress and Bridge Policy
• Bridge Funding and the IIJA
• New Bridge Programs
• Bridge Formula Program
• Bridge Investment Program
• Federal Lands and Tribal Bridges
• Other Program Sources of Bridge Funding
• FHWA's Emergency Relief Program
• Non-bridge Programs That Can Assist Bridge Projects
• Annual Appropriated Funds
• Bridge Spending History, FY2016-FY2025
• Future Bridge Funding Needs
• Issues for Congress
• Bridge Funding Programs
• Type of Funding Distribution
• Nonfederal Funding for Bridges
• Spending on Off-System Bridges

Figures

• Figure 1. Urban and Rural Highway Bridges in Poor Condition, 2012-2025
• Figure 2. Trends in Federal Bridge Obligations by Program, FY2016-FY2025
• Figure 3. Estimated Effect of Various Spending Levels on Bridge Investment Backlog

Tables

• Table 1. Bridge Condition Ratings, 2012 and 2025
• Table 2. New Highway Bridge Programs: IIJA Funding
• Table 3. Bridge Funding in Annual Appropriations Acts
• Table A-1. Bridge Condition by State and Territory
• Table A-2. Bridge Obligations by Program: FY2016-FY2025

Appendixes

• Appendix.

Summary

The United States has approximately 624,000 bridges longer than 20 feet on public roads. About ,000 bridges longer than 20 feet on public roads. About
Specialist in
48% of these bridges are owned by state governments and 50% by local governments. The 48% of these bridges are owned by state governments and 50% by local governments. The
Transportation Policy
number of bridges classified as poor has declined gradually for many years, but as of June number of bridges classified as poor has declined gradually for many years, but as of June 2021,

2025, about about 4442,000 remain. The Infrastructure Investment and Jobs Act (IIJA; P.L. 117-58), enacted on ,000 remain. The Infrastructure Investment and Jobs Act (IIJA; P.L. 117-58), enacted on
William J. Mallett
November 15, 2021, established federal programs specifically to fund bridges for the first time November 15, 2021, established federal programs specifically to fund bridges for the first time
Specialist in
since FY2012 and significantly increased the total amount of federal funding that can be used for since FY2012 and significantly increased the total amount of federal funding that can be used for
Transportation Policy
bridge construction and repair. bridge construction and repair.

The actThe IIJA provided funding for FY2022 through FY2026. The IIJA created two large stand-alone bridge programs, the Bridge Formula Program and the created two large stand-alone bridge programs, the Bridge Formula Program and the

Bridge Investment Program, authorized at $27.5 billion and $15.8 billion, respectively, over five Bridge Investment Program, authorized at $27.5 billion and $15.8 billion, respectively, over five
years. In addition, the average annual authorizations for the so-called core highway programs that can provide funding for years. In addition, the average annual authorizations for the so-called core highway programs that can provide funding for
both roads and bridges were increased by roughly 26% over the FY2021 baseline unadjusted for inflation; this money is both roads and bridges were increased by roughly 26% over the FY2021 baseline unadjusted for inflation; this money is
distributed by formula to the states, which can use it for bridge projects at their discretion. The IIJA also increased funding of distributed by formula to the states, which can use it for bridge projects at their discretion. The IIJA also increased funding of
existing discretionary surface transportation programs and created several new discretionary programs to which local entities existing discretionary surface transportation programs and created several new discretionary programs to which local entities
and the states can apply directly to the U.S. Department of Transportation. Bridge projects that match the program criteria are and the states can apply directly to the U.S. Department of Transportation. Bridge projects that match the program criteria are
eligible under some of these programs.eligible under some of these programs.
Based on an analysis by the Federal Highway Administration of bridge funding needs, the IIJA could conceivably allow state
and local governments to spend for five years at a level that would eliminate the national backlog in bridge repair Adjusted for inflation, average annual bridge spending (as measured by funding obligations) has been 22% higher in the IIJA period (FY2022-FY2025) to date than under the previous authorization law, the Fixing America's Surface Transportation Act (FAST Act; P.L. 114-94 ) as extended (FY2016 through FY2021). Average annual spending has been $12.0 billion in the IIJA period to date and $9.8 billion in the FAST Act period (FY2025 dollars). Based on an analysis by the Federal Highway Administration of bridge funding needs, this level of spending combined with nonfederal spending could reduce the bridge investment backlog by about 90% if continued if continued
over a 20-year periodover a 20-year period. , although additional funds would be needed for the construction of new bridges. The vast majority of bridges in poor condition, over four out of five, are in rural areas. These bridges The vast majority of bridges in poor condition, over four out of five, are in rural areas. These bridges
tend to be small and relatively lightly traveled. In urban areas, bridges in poor condition, while far fewer, are generally much tend to be small and relatively lightly traveled. In urban areas, bridges in poor condition, while far fewer, are generally much
larger and, therefore, more expensive to fix. In larger and, therefore, more expensive to fix. In 20212025, 58% of the deck area classified as in poor condition was on urban , 58% of the deck area classified as in poor condition was on urban
bridges. Bridges on roads carrying heavy traffic loads, particularly Interstate Highway bridges, are generally in better bridges. Bridges on roads carrying heavy traffic loads, particularly Interstate Highway bridges, are generally in better
condition than those on more lightly traveled routes. Although improvements have been made in most states, there remain condition than those on more lightly traveled routes. Although improvements have been made in most states, there remain
major differences among states in the share of bridges in poor condition. For example, about major differences among states in the share of bridges in poor condition. For example, about 2018% of bridges in West Virginia % of bridges in West Virginia
were classified as poor in were classified as poor in 20212025, whereas in Nevada the share , whereas in Nevada the share iswas 1%. The IIJA reaffirmed congressional support for the 1%. The IIJA reaffirmed congressional support for the
improvement of bridges on smaller roads that are not part of the federal-aid system by making these so-called improvement of bridges on smaller roads that are not part of the federal-aid system by making these so-called “"off-system off-system
bridges”bridges" eligible under the new bridge programs. eligible under the new bridge programs.
The IIJA replaced the former policy of gradual improvement of the nationThe IIJA replaced the former policy of gradual improvement of the nation’'s bridges with a more ambitious program to speed s bridges with a more ambitious program to speed
up the pace of bridge improvements. The implementation of this policy and its success in improving bridge conditions are up the pace of bridge improvements. The implementation of this policy and its success in improving bridge conditions are
likely to be of ongoing concern to Congress. likely to be of ongoing concern to Congress. In particular, despite the large increase in nominal funding, it is possible thatOther potential issues in reauthorization of the the
IIJA will lead to less bridge repair and replacement than anticipated. Among the potential reasons include the following:
 Rising highway construction costs are eroding the purchasing power of the amounts authorized and
appropriated in the IIJA.
 Potential state decisions to use federal highway funds on road projects instead of bridges and state and local
fiscal substitution of federal for nonfederal funds could reduce the impact of the increase in bridge
spending provided for in the IIJA.
 The large increase in federal grants for bridges under the IIJA could discourage use of tolling as a funding
option for state and local governments.
Congress’s interest in funding off-system bridges, which are mostly located in rural areas, was affirmed under the
IIJA. In addition to continuing the existing off-system bridge spending requirements, the IIJA madeIIJA include

the reduction in funding flexibility afforded state DOTs by dedicated bridge programs;

the competitive distribution of some bridge funding—competitive funding has the potential of focusing funds on bridge projects with the greatest benefits, but state DOTs generally prefer formula funds that provide known funding amounts with less administrative effort;

whether the large increase in federal grants for bridges under the IIJA has discouraged state and local funding, including the use of tolling as a funding option; and

the eligibility of off-system off-system
bridges eligible under the new bridge programs. The policy could be an issue if it constrains resources available to
repair or replacebridges and whether the repair or replacement of more heavily traveled bridges on major roads would constrain resources.

Introduction

The United States has approximately 624 more heavily traveled bridges on major roads.

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Contents
Introduction ..................................................................................................................................... 1
Bridge Characteristics ..................................................................................................................... 1
Bridge Inspection ...................................................................................................................... 1
Bridge Conditions ..................................................................................................................... 2
Bridge Infrastructure Funding ......................................................................................................... 4
Federal and State Roles ............................................................................................................. 4
Congress and Bridge Policy ...................................................................................................... 5
Recent Spending History, FY2015-FY2021 ............................................................................. 5
Additional Appropriated Funds ........................................................................................... 6
Bridge Funding and Policy Changes in the IIJA ............................................................................. 7
New Bridge Programs ............................................................................................................... 7
Bridge Formula Program ........................................................................................................... 8
Bridge Investment Program ...................................................................................................... 8
Federal Lands and Tribal Bridges ............................................................................................. 9
Other Program Sources of Bridge Funding ............................................................................... 9
FHWA’s Emergency Relief Program ................................................................................ 10
New Non-bridge Programs That Can Assist Bridge Projects ........................................... 10
Future Bridge Funding Needs .................................................................................................. 11
Issues for Congress ........................................................................................................................ 12
Loss of Purchasing Power ....................................................................................................... 12
Programmatic Substitution ...................................................................................................... 13
Maintenance of Effort ............................................................................................................. 13
Tolling of Non-tolled Bridges ................................................................................................. 13
Spending on Off-System Bridges ............................................................................................ 14

Figures
Figure 1. Urban and Rural Highway Bridges in Poor Condition, 2012-2021 ................................. 3
Figure 2. Estimated Effect of Various Spending Levels on Bridge Investment Backlog .............. 12

Tables
Table 1. Bridge Condition Ratings, 2012 and 2021 ........................................................................ 3
Table 2. Trends in Federal Bridge Obligations, FY2015-FY2021 .................................................. 6
Table 3. New Highway Bridge Programs: IIJA Funding ................................................................. 7

Table A-1. Bridge Condition by State and Territory ...................................................................... 15
Table A-2. Bridge Obligations by Program: FY2015-FY2021 ..................................................... 17

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Appendixes
Appendix. ...................................................................................................................................... 15

Contacts
Author Information ........................................................................................................................ 18

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Highway Bridges: Conditions, Funding Programs, and Issues for Congress

Introduction
The United States has approximately 620,000 bridges longer than 20 feet on public roads. The ,000 bridges longer than 20 feet on public roads. The
number of bridges classified as poor has declined gradually for many years, but as of June number of bridges classified as poor has declined gradually for many years, but as of June 2021,
2025, about about 4442,000 remain. Most of these bridges are owned and maintained by state and local ,000 remain. Most of these bridges are owned and maintained by state and local
governments. The federal government has established bridge inspection standards and provides governments. The federal government has established bridge inspection standards and provides
funding to support the rehabilitation and replacement of existing bridges and the construction of funding to support the rehabilitation and replacement of existing bridges and the construction of
new bridges.new bridges.
Bridges in poor condition can be restricted by weight, and unsafe bridges are typically closed to traffic. Failures due to poor conditions have occurred, such as the Fern Hollow Bridge in Pittsburgh, PA, in 2022 that caused several injuries but no deaths.¹ Poor bridge conditions can cause severe disruption to the highway system. The passage of the Infrastructure Investment and Jobs Act (IIJA; P.L. 117-58), covering the years The passage of the Infrastructure Investment and Jobs Act (IIJA; P.L. 117-58), covering the years
FY2022-FY2026, initiated a major change in congressional bridge funding policy. Prior to FY2022-FY2026, initiated a major change in congressional bridge funding policy. Prior to
passage, federal bridge funding came from programmatic sources that could be spent on either passage, federal bridge funding came from programmatic sources that could be spent on either
roads or bridges in accordance with priorities set by the states. The IIJA authorized $43.3 billion roads or bridges in accordance with priorities set by the states. The IIJA authorized $43.3 billion
over five years exclusively for bridge projects; increased authorizations for formula grants that over five years exclusively for bridge projects; increased authorizations for formula grants that
states may choose to use for bridges; and expanded funding for discretionary programs under states may choose to use for bridges; and expanded funding for discretionary programs under
which bridge projects are eligible.which bridge projects are eligible.
This report examines current bridge characteristics and conditions, national funding needs, and This report examines current bridge characteristics and conditions, national funding needs, and
the implications of the attempt in the IIJA to speed up the pace of bridge improvements. It the implications of the attempt in the IIJA to speed up the pace of bridge improvements. It
concludes with a discussion of issues that may be of congressional concern, concludes with a discussion of issues that may be of congressional concern, especially in reauthorization of the surface transportation programs, including the including the
potential impact of inflation on future bridge spending, the future of toll-funded bridges, and potential impact of inflation on future bridge spending, the future of toll-funded bridges, and
spending on bridges not on the federal-aid system.spending on bridges not on the federal-aid system.
Bridge Characteristics
Of the Of the 620624,000 bridges on public roads, about 48% are owned by state governments, and 50% are ,000 bridges on public roads, about 48% are owned by state governments, and 50% are
owned by local governments. State governments generally own the larger and more heavily owned by local governments. State governments generally own the larger and more heavily
traveled bridges, such as those on the Interstate Highway system. Less than 2% of highway traveled bridges, such as those on the Interstate Highway system. Less than 2% of highway
bridges are owned by the federal government, primarily those on federally owned land.bridges are owned by the federal government, primarily those on federally owned land.1
2 About 9% of all bridges carry Interstate Highways, and another About 9% of all bridges carry Interstate Highways, and another 1415% serve principal arterial % serve principal arterial
highways other than Interstates.highways other than Interstates.23 Interstate and other principal arterial bridges carry about 80% of Interstate and other principal arterial bridges carry about 80% of
average daily bridge traffic. The highest traffic loads are on Interstate Highway bridges in urban average daily bridge traffic. The highest traffic loads are on Interstate Highway bridges in urban
areas; these accounted for only areas; these accounted for only 56% of all bridges but carried 37% of average daily bridge traffic % of all bridges but carried 37% of average daily bridge traffic
in 2021.3
in 2025.⁴ Bridge Inspection
Under the National Bridge Inspection Program, all bridges longer than 20 feet on public roads Under the National Bridge Inspection Program, all bridges longer than 20 feet on public roads
must be inspected by qualified inspectors, based on federally defined requirements (23 U.S.C. must be inspected by qualified inspectors, based on federally defined requirements (23 U.S.C.
§144). Federal agencies are subject to the same requirements for federally owned bridges, such as §144). Federal agencies are subject to the same requirements for federally owned bridges, such as
those on federal lands. Data from these inspections are reported to the Federal Highway

1 Federal Highway Administration (FHWA), National Bridge Inventory, “Bridge Condition by Owner, 2021,” at
https://www.fhwa.dot.gov/bridge/nbi/no10/owner21.cfm.
2 Arterials, including Interstates, are roads designed to provide for relatively long trips at high speed and usually have
multiple lanes and limited access. Principal arterials exclude rural and urban minor arterials. FHWA, National Bridge
Inventory, “Bridge Condition by Functional Classification, 2021,” at http://www.fhwa.dot.gov/bridge/britab.cfm.
3 FHWA, National Bridge Inventory, “Bridge Condition by Functional Classification, Average Daily Travel (ADT),
2021,” at https://www.fhwa.dot.gov/bridge/nbi/no10/fcadt21.cfm.
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Highway Bridges: Conditions, Funding Programs, and Issues for Congress

those on federal lands. Data from these inspections are reported to the Federal Highway Administration (FHWA), which uses them to compile a list of bridges in poor condition. States Administration (FHWA), which uses them to compile a list of bridges in poor condition. States
may use this information to identify which bridges need replacement or repair.may use this information to identify which bridges need replacement or repair.4
5 FHWA oversees bridge inspection through the National Bridge Inspection Standards (NBIS).FHWA oversees bridge inspection through the National Bridge Inspection Standards (NBIS).5
6 The NBIS set forth how, with what frequency, and by whom bridge inspection is to be completed. The NBIS set forth how, with what frequency, and by whom bridge inspection is to be completed.
The standards provide the following:The standards provide the following:
 Each state is responsible for the inspection of all public highway bridges within Each state is responsible for the inspection of all public highway bridges within
the state except for those owned by the federal government or Indian tribes. the state except for those owned by the federal government or Indian tribes.
Although the state may delegate some bridge inspection responsibilities to Although the state may delegate some bridge inspection responsibilities to
smaller units of government, the responsibility for having the inspections done in smaller units of government, the responsibility for having the inspections done in
conformance with federal requirements remains with the state.conformance with federal requirements remains with the state.
 Inspections can be done by anyone qualified under the standards for qualification Inspections can be done by anyone qualified under the standards for qualification
and training. The inspectors may be state employees, consultants to the states, or and training. The inspectors may be state employees, consultants to the states, or
others.others.
 Inspection of a federally owned bridge is the responsibility of the federal agency Inspection of a federally owned bridge is the responsibility of the federal agency
that owns the bridge.that owns the bridge.
 In general, a bridge must be inspected at least every 24 months. States are to In general, a bridge must be inspected at least every 24 months. States are to
identify bridges that require less than a 24-month interval. States can also request identify bridges that require less than a 24-month interval. States can also request
FHWA approval to inspect certain bridges at intervals as long as 48 months. The FHWA approval to inspect certain bridges at intervals as long as 48 months. The
interval for an underwater inspection is generally 60 months but may be interval for an underwater inspection is generally 60 months but may be
increased to 72 months with FHWA permission. Nonredundant steel tension increased to 72 months with FHWA permission. Nonredundant steel tension
members must undergo a hands-on inspection at intervals not to exceed 48 members must undergo a hands-on inspection at intervals not to exceed 48
months.months.6
 7 An on-site inspection team must have a leader who meets additional training An on-site inspection team must have a leader who meets additional training
requirements. Damage and special inspections do not require the presence of a requirements. Damage and special inspections do not require the presence of a
team leader.team leader.
 Load rating of a bridge must be under the responsibility of a registered Load rating of a bridge must be under the responsibility of a registered
professional engineer. Structures that cannot carry maximum legal loads for the professional engineer. Structures that cannot carry maximum legal loads for the
roadway must be posted.roadway must be posted.
The vast majority of inspections are performed under state authority. FHWA bridge engineers, at The vast majority of inspections are performed under state authority. FHWA bridge engineers, at
times, perform field reviews to assure that states are complying with the bridge inspection times, perform field reviews to assure that states are complying with the bridge inspection
requirements. FHWA also provides on-site engineering expertise in the examination of the causes requirements. FHWA also provides on-site engineering expertise in the examination of the causes
of catastrophic bridge failures.of catastrophic bridge failures.
Bridge Conditions
Bridge condition data reported to FHWA are collected in the National Bridge Inventory. This Bridge condition data reported to FHWA are collected in the National Bridge Inventory. This
information permits FHWA to characterize the existing condition of bridges as good, fair, or poor. information permits FHWA to characterize the existing condition of bridges as good, fair, or poor.
A bridge is considered in good condition if the deck, superstructure, and substructure are rated at A bridge is considered in good condition if the deck, superstructure, and substructure are rated at
least 7 on a 0-9 scale. If any of these bridge elements is rated 5 or 6, a bridge is considered in fair least 7 on a 0-9 scale. If any of these bridge elements is rated 5 or 6, a bridge is considered in fair
condition. A bridge is considered in poor condition if any element is rated 4 or less. A bridge condition. A bridge is considered in poor condition if any element is rated 4 or less. A bridge

4 The National Bridge Inspection Program was initiated in 1968 following the 1967 collapse of the so-called Silver
Bridge over the Ohio River. The National Bridge Inspection Standards were first issued in 1971. See FHWA, “Tables
of Frequently Requested NBI Information,” at http://www.fhwa.dot.gov/bridge/britab.cfm.
5 23 C.F.R. §650, subpart C.
6 A nonredundant steel tension member is a primary steel member in tension, or with a tension element, whose failure
would probably cause a portion of or the entire bridge to collapse. A nonredundant steel tension member was
previously known in regulation as a fracture critical member.
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Highway Bridges: Conditions, Funding Programs, and Issues for Congress

classified as poor is not necessarily unsafe but may require the posting of a vehicle weight classified as poor is not necessarily unsafe but may require the posting of a vehicle weight
restriction. When officials determine that a bridge is unsafe, it is closed to traffic. In restriction. When officials determine that a bridge is unsafe, it is closed to traffic. In 20212025, about , about
3,500 (0.53,600 (less than 1%) bridges were closed and another 62,000 (10%) had a weight restriction.%) bridges were closed and another 62,000 (10%) had a weight restriction.
In 2021, 2788 In 2025, 272,000 public road bridges (,000 public road bridges (4544%) were considered good, %) were considered good, 298310,000 (,000 (4850%) fair, and %) fair, and
4442,000 (7%) poor. The number of poor bridges declined by about ,000 (7%) poor. The number of poor bridges declined by about 1315,000 over the ,000 over the 1014-year period -year period
from 2012 to from 2012 to 20212025, whereas the number of bridges in good condition dropped by , whereas the number of bridges in good condition dropped by 914,000, and the ,000, and the
number of bridges in fair condition increased by number of bridges in fair condition increased by 3547,000 ,000 (Table 1).
Table 1. Bridge Condition Ratings, 2012 and 2021
2012
2021

Rating
Number Percentage Number Percentage
Good
287,194
47.3
278,128
44.9
Fair
262,878
43.3
297,908
48.1
Poor
57,049
9.4
43,586
7.0
Total
607,121
100.0
619,622
100.0
2025

2012

2025

Rating

Number

Percentage

Number

Percentage

Good

287,194

47.3

272,779

43.7

Fair

262,878

43.3

309,729

49.6

Poor

57,049

9.4

41,685

6.7

Total

607,121

100.0

624,193

100.0

Source: Bureau of Transportation Statistics, Bureau of Transportation Statistics, National Transportation Statistics, Table 1-28, , Table 1-28, at https://www.bts.gov/https://www.bts.gov/
content/condition-us-highway-bridgescontent/condition-us-highway-bridges.
Notes: Data for 2012 are as of December 31. Data for 2021 are as of June 15.
. Notes: Bridge counts and conditions for 2012 were finalized and published as of December 31, 2012. Bridge counts and conditions for 2025 were finalized and published as of June 15, 2025. About 80% of the bridges in poor condition in About 80% of the bridges in poor condition in 20212025 were located in rural areas. Nevertheless, were located in rural areas. Nevertheless,
urban bridges in poor condition are generally much larger and carry more traffic than those in urban bridges in poor condition are generally much larger and carry more traffic than those in
rural areas and, therefore, are more expensive to fix. In rural areas and, therefore, are more expensive to fix. In 20212025, 58% of the total deck area of , 58% of the total deck area of
bridges in poor condition was in urban areas. The amount of deck area in poor condition has bridges in poor condition was in urban areas. The amount of deck area in poor condition has
dropped by about the same proportion in urban and rural areas from 2012 through dropped by about the same proportion in urban and rural areas from 2012 through 2021, nearly
30%.
Figure 1. Urban and Rural Highway Bridges in Poor Condition, 2012-2021

Source: Bureau of Transportation Statistics, National Transportation Statistics, Table 1-28, at https://www.bts.gov/
content/condition-us-highway-bridges.
Notes: Data for 2012-2020 are as of December 31. Data for 2021 are as of June 15.
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2025, roughly 30% (Figure 1). Bridges on Interstate Highways are generally in better condition than those on more lightly Bridges on Interstate Highways are generally in better condition than those on more lightly
traveled routes: 3% of urban Interstate Highway bridges were considered poor in traveled routes: 3% of urban Interstate Highway bridges were considered poor in 20212025, whereas , whereas
76% of urban bridges on local roads were classified as poor.% of urban bridges on local roads were classified as poor.79 Likewise, 3% of rural Interstate Likewise, 3% of rural Interstate
Highway bridges were poor in Highway bridges were poor in 20192025, compared with , compared with 1110% of rural bridges on local roads. In % of rural bridges on local roads. In 2021,
2025, 9% of bridges owned by local governments were classified as poor, compared with 9% of bridges owned by local governments were classified as poor, compared with 54% of state-% of state-
owned bridges. For bridge condition ratings by state and territory, seeowned bridges. For bridge condition ratings by state and territory, see Table A-1.
Bridge Infrastructure Funding
Federal and State Roles
Federal bridge funding shares the basic attributes of federal aid to highways, which is
administered by FHWA.8 Most of this funding is apportioned by formula to the states from the
Highway Trust Fund and is not subject to annual appropriation by Congress. Each state’s funds
are divided among 10 so-called core formula programs established by law. State departments of
transportation (state DOTs) are free to spend the funds allocated to each program in any way
consistent with that program’s purposes, so long as they comply with detailed federal planning
guidelines and performance management measures.9 State DOTs execute the contracts and
oversee the construction process. The decision about how much of a state’s formula funding to
spend on bridges rather than roads is generally up to the state DOT.10 States are allowed to
transfer (“flex”) up to 50% of each core formula program’s apportioned funds to other formula
programs.11 Most bridge projects receive a federal cost share of up to 80%, but for bridges on
Interstate Highways, the share is generally up to 90%. The use of federal funds for bridges, unlike
most road funding, is not restricted to designated federal-aid highways and may be used on any
bridge listed in the National Bridge Inventory.
In addition, states or municipalities may seek discretionary (competitive) grants awarded by
FHWA or the Office of the Secretary of Transportation. For example, the Nationally Significant

7 Interstates are the highest class of roadways in FHWA’s functional classification system, and local roads are the
lowest.
8 CRS Report R47022, Federal Highway Programs: In Brief, by Robert S. Kirk.
9 FHWA’s Final Rule for National Performance Management Measures: Assessing Pavement Condition for the
National Highway Performance Program and Bridge Condition for the National Highway Performance Program
became effective on February 17, 2017. See 82 Federal Register 5886, at https://www.federalregister.gov/documents/
2017/01/18/2017-00550/national-performance-management-measures-assessing-pavement-condition-for-the-national-
highway.
10 The main exception under the core formula programs is that under the Surface Transportation Block Grant Program
(STBG), an amount equal to 15% of a state’s FY2009 Highway Bridge Program apportionment must be set aside from
certain population-based set-asides for spending on off-system bridges. Another of the programs, the National Highway
Performance Program, requires that, if in the preceding three years more than 10% of the total deck area of bridges in
the state on the National Highway System (NHS) is located on bridges classified in poor condition, the state must set
aside an amount equal to 50% of the state’s FY2009 Highway Bridge Program apportionment for eligible projects on
bridges on the NHS. The penalty remains in effect until the NHS deck area on bridges in poor condition is brought
below 10% of the total NHS deck area in the state.
11 Metropolitan Planning Program funds and suballocated funds under the STBG are among those shielded from
transfer. See FHWA, “Transferability of Apportioned Program Funding under 23 U.S.C. 126,” at
https://www.fhwa.dot.gov/cfo/23usc126_transferability.cfm.
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Table A-1.

Figure 1. Urban and Rural Highway Bridges in Poor Condition, 2012-2025 Source: Bureau of Transportation Statistics, National Transportation Statistics, Table 1-28, https://www.bts.gov/content/condition-us-highway-bridges.

Notes: Bridge counts and conditions for 2012-2020 were finalized and published as of December 31 of each year. Beginning in 2021, bridge counts and conditions were finalized and published as of June 15 of each year.

Bridge Vulnerabilities to Extreme Events

In addition to obsolescence and deterioration due to aging and vehicle use, bridges are vulnerable to other kinds of risks, sometimes called "extreme events," including natural hazards (earthquakes, flooding, wildfires, etc.), vehicle fires, and vessel strikes.¹⁰ Bridges can be made more resilient to these risks by initial design or by retrofitting. Some states in the western United States, for instance, have been following seismic design practices since the early 1970s, after the 1971 San Fernando, CA, earthquake.¹¹ In many situations, identifying risks can be difficult and the mitigation costs can be prohibitive.

Public awareness about the vulnerability of certain bridges to vessel strikes was heightened when, on March 26, 2024, the containership Dali collided with the Francis Scott Key Bridge in Baltimore, MD, causing it to collapse. As part of its investigation of the incident, the National Transportation Safety Board (NTSB) completed a vulnerability assessment of the Key Bridge to collapse from a vessel strike.¹² NTSB concluded that the Key Bridge was above an acceptable threshold of collapse risk from a vessel strike as established by the American Association of State Highway and Transportation Officials (AASHTO). NTSB "also identified 68 other bridges frequented by ocean-going vessels that were constructed before the AASHTO guidance was issued in 1991, have not undergone a vulnerability assessment based on recent vessel traffic, and, therefore, have an unknown level of risk of collapse from a vessel collision."¹³ Thus, NTSB called on these bridge owners to conduct an assessment and, if necessary, to "develop and implement a risk reduction plan that includes input from the interdisciplinary team [consisting of FHWA, Coast Guard, and Corps of Engineers], identifies short- and long-term strategies to reduce risk, and considers the safety of the vessels and structures in the waterways."¹⁴

According to NTSB, as of November 25, 2025, bridge owners of 22 of the 68 bridges had reported that they were under the AASHTO threshold, and 14 were over the threshold with risk reduction planning in progress. Vulnerability assessments of the remaining 32 bridges were reported as being "in progress."¹⁵ According to one news report, the Delaware River Port Authority is developing protection for two bridges at risk of vessel strikes—the Benjamin Franklin Bridge and the Walt Whitman Bridge. Costs of these projects were reported as being "about $100 million to $150 million for each bridge." Some vulnerable bridges, such as the Chesapeake Bay Bridge in Maryland, might need to be replaced, presumably at greater cost than adding protection to existing facilities.¹⁶

Bridge Infrastructure Funding Federal and State Roles

Federal bridge funding shares the basic attributes of federal aid to highways, which is administered by FHWA.¹⁷ Most of this funding is apportioned by formula to the states from the Highway Trust Fund and is not subject to annual appropriation by Congress. Each state's funds are divided among 10 so-called core formula programs established by law. State departments of transportation (state DOTs) are free to spend the funds allocated to each program in any way consistent with that program's purposes, so long as they comply with detailed federal planning guidelines and performance management measures.¹⁸ State DOTs execute the contracts and oversee the construction process. The decision about how much of a state's formula funding to spend on bridges rather than roads is generally up to the state DOT.¹⁹ States are allowed to transfer ("flex") up to 50% of each core formula program's apportioned funds to other formula programs.²⁰ Most bridge projects receive a federal cost share of up to 80%, but for bridges on Interstate Highways, the share is generally up to 90%. The use of federal funds for bridges, unlike most road funding, is not restricted to designated federal-aid highways and may be used on any bridge listed in the National Bridge Inventory.

In addition, states or municipalities may seek discretionary (competitive) grants awarded by FHWA or the Office of the Secretary of Transportation. For example, the Nationally Significant Freight and Highway Projects Program (renamed INFRA) also may award funding for large Freight and Highway Projects Program (renamed INFRA) also may award funding for large
bridge projects.bridge projects.12
21 Congress and Bridge Policy
For the first 53 years of federal aid to highways, federal policy left decisions about allocating For the first 53 years of federal aid to highways, federal policy left decisions about allocating
money to bridge projects to the states. There was no federal program funding dedicated to money to bridge projects to the states. There was no federal program funding dedicated to
bridges. This changed following the collapse of the so-called Silver Bridge over the Ohio River in bridges. This changed following the collapse of the so-called Silver Bridge over the Ohio River in
December 1967, which resulted in the deaths of 46 people. Congress required the Secretary of December 1967, which resulted in the deaths of 46 people. Congress required the Secretary of
Transportation to establish the NBIS in 1968. In February 1970, FHWA reported that of the Transportation to establish the NBIS in 1968. In February 1970, FHWA reported that of the
563,000 bridges in the United States, 88,900 were 563,000 bridges in the United States, 88,900 were “"critically deficient.critically deficient.”" Despite the findings, the Despite the findings, the
agency recommended against funding a agency recommended against funding a “"special bridge programspecial bridge program”" on the grounds that such a on the grounds that such a
program would program would “"necessarily be at the expense of other urgent highway needs.necessarily be at the expense of other urgent highway needs.”13
"²² Contrary to this recommendation, the Federal-Aid Highway Act of 1970 (P.L. 95-599) authorized Contrary to this recommendation, the Federal-Aid Highway Act of 1970 (P.L. 95-599) authorized
the discretionary Special Bridge Replacement Program, the first stand-alone federal highway the discretionary Special Bridge Replacement Program, the first stand-alone federal highway
bridge funding program. Having a stand-alone program was a way for Congress to dedicate bridge funding program. Having a stand-alone program was a way for Congress to dedicate
certain funding to bridges rather than roads. The Surface Transportation Assistance Act of 1978 certain funding to bridges rather than roads. The Surface Transportation Assistance Act of 1978
((P.L. 95-599) replaced this with a new formula-based Highway Bridge Replacement and P.L. 95-599) replaced this with a new formula-based Highway Bridge Replacement and
Rehabilitation Program, which expanded eligibilities to include bridge rehabilitation and projects Rehabilitation Program, which expanded eligibilities to include bridge rehabilitation and projects
on off-system bridges. Roughly 20% of the programon off-system bridges. Roughly 20% of the program’'s funding was set aside for a bridge s funding was set aside for a bridge
discretionary program for large bridge projects. These discretionary funds were under the control discretionary program for large bridge projects. These discretionary funds were under the control
of FHWA.of FHWA.
The 1991 Intermodal Surface Transportation Efficiency Act (P.L. 102-240) allowed a state to The 1991 Intermodal Surface Transportation Efficiency Act (P.L. 102-240) allowed a state to
transfer 40% of its bridge apportionment to other highway programs (the percentage was transfer 40% of its bridge apportionment to other highway programs (the percentage was
increased to 50% in 1998). The Moving Ahead for Progress in the increased to 50% in 1998). The Moving Ahead for Progress in the 21st21^st Century Act (MAP-21; Century Act (MAP-21;
P.L. 112-141), enacted in 2012, allowed the dedicated bridge program—then called the Highway P.L. 112-141), enacted in 2012, allowed the dedicated bridge program—then called the Highway
Bridge Program—to expire at the end of FY2012, largely returning the decision to the states on Bridge Program—to expire at the end of FY2012, largely returning the decision to the states on
how much of their federal formula grants to spend on bridges. This situation persisted until how much of their federal formula grants to spend on bridges. This situation persisted until
Congress passed the IIJA, which reasserted bridge spending as a congressional priority.Congress passed the IIJA, which reasserted bridge spending as a congressional priority.
Recent Spending History, FY2015-FY2021
Under the Fixing America’s Surface Transportation Act (FAST Act; P.L. 114-94), as amended
through FY2021, bridge projects were funded from highway programs that states or grantees
could also use to fund road projects. States also had access to residual funds from the expired
Highway Bridge Program. Table 2 shows the total obligation of federal funding for bridges,
including funds from the former Highway Bridge Program and those from all other programmatic
sources, from FY2015 through FY2021. The table also expresses obligations in constant FY2015
dollars to show the impact of inflation.

12 INFRA awards are administered by the Office of the Secretary of Transportation, not by FHWA.
13 U.S. Congress, House Committee on Public Works, 1970 National Highway Needs Report, committee print, 91st
Cong., 2nd sess., February 1970, H.Prt. 91-27 (Washington, DC: GPO, 1970), pp. 30-32. The report estimated that there
were 24,000 deficient bridges on the federal-aid system and 64,900 deficient bridges off the federal-aid system.
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Table 2. Trends in Federal Bridge Obligations, FY2015-FY2021
(current and inflation-adjusted dollars in millions)

FY2015
FY2016
FY2017
FY2018
FY2019
FY2020
FY2021
Total (Current $)
$6,804
$7,095
$6,666
$7,092
$7,365
$7,797
$8,569
% Change from

+4%
-6%
+6%
+4%
+6
+10
Previous Year
Highway Bridge
Program (pre-FY2013
$243
$80
$72
$44
$2
$56
-$38
Program)
Surface Transportation
$604
$587
$558
$1,662
$2,212
$2,317
$2,173
Block Grant Program
National Highway
$3,638
$3,910
$3,937
$3,790
$4,033
$4,171
$3,998
Performance Program
All Other Programs
$2,319
$2,518
$2,099
$1,596
$1,118
$1,253
$2,436
Total (Inflation-
$6,804
$7,078
$6,492
$6,613
$6,682
$7,003
$7,379a
Adjusted, 2015$)
% Change from

+4%
-8%
+2%
+1%
+5
+5%
Previous Year
Sources: Federal Highway Administration (FHWA). Cost adjustments for FY2016-FY2020 calculated by CRS
using Bureau of Economic Analysis, Price Indexes for Gross Government Fixed Investment by Type, National Income
and Product Accounts Table 5.9.4, Line 40: State and local highways and streets. Weighted average used to
approximate fiscal years.
Notes: For a detailed table of bridge obligations for these years, see Table A-2. Totals reflect ongoing
obligations of funds under prior authorizations. Totals may not add due to rounding. Highway Bridge Program
funding for FY2015-FY2021 reflects funds unobligated when the program was discontinued at the end of FY2012.
Surface Transportation Block Grant Program includes both Surface Transportation Program and Surface
Transportation Block Grant Program funds. Annual appropriations from FY2018 to FY2020 are included in All
Other Programs.
a. FY2021 cost adjustment based on FHWA, National Highway Construction Cost Index, adjusted to fiscal year
average.
During FY2021, obligations for spending on bridges were approximately 26% higher than in
FY2015. When adjusted for inflation in road construction costs, however, the increase was about
8% during these years.
Additional Appropriated Funds
Beginning in FY2018, Congress has appropriated funding for bridges outside the authorization
process. The Consolidated Appropriations Act, 2018 (P.L. 115-141) included $225 million for a
competitive bridge program for states with a population density of 100 per square mile or less.
The Consolidated Appropriations Act, 2019 (P.L. 116-6) provided $475 million for a Bridge
Replacement and Rehabilitation Program, to be distributed by formula to states for which the
percent of total bridge deck area classified as poor was at least 7.5%. The Further Consolidated
Appropriations Act, 2020 (P.L. 116-94) provided $1.15 billion but broadened the eligibility to
states for which the percentage of total bridge deck area classified as poor is at least 5%. The
Consolidated Appropriations Act, 2021 (P.L. 116-260) provided $1.08 billion for this program.
For these years, Congress in effect pursued a two-pronged approach by making bridges eligible
for funding at state discretion under the large highway formula programs established in
authorization acts and supplementing these funds with targeted bridge funding in annual
appropriations acts.
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Bridge Funding and Policy Changes in the IIJA
Bridge Funding and the IIJA The IIJA both reauthorized spending authority from the Highway Trust Fund for highway The IIJA both reauthorized spending authority from the Highway Trust Fund for highway
programs at an increased level and provided an additional boost to infrastructure spending via programs at an increased level and provided an additional boost to infrastructure spending via
multiyear supplemental appropriations from the Treasury general fund. Some programs multiyear supplemental appropriations from the Treasury general fund. Some programs are
were authorized to receive additional funding subject to appropriation in future annual appropriations authorized to receive additional funding subject to appropriation in future annual appropriations
acts.acts.
New Bridge Programs
The IIJA created two stand-alone programs dedicated to bridge projects:The IIJA created two stand-alone programs dedicated to bridge projects:
 The Bridge Replacement, Rehabilitation, Preservation, Protection, and The Bridge Replacement, Rehabilitation, Preservation, Protection, and
Construction Program, generally referred to as the Bridge Formula Program Construction Program, generally referred to as the Bridge Formula Program
(BFP), is to distribute $5.5(BFP), was authorized at $5.50 billion annually billion annually to the states through FY2026.through FY2026.
 The Bridge Investment Program (BIP) The Bridge Investment Program (BIP) iswas authorized authorized to distribute nearly $16
at an annual average $3.15 billion in competitive grants through FY2026, although billion in competitive grants through FY2026, although $3.265an annual average $0.65 billion of that billion of that
amount amount iswas subject to future appropriations subject to future appropriations (see Table 32). Table 2. New Highway Bridge Programs: IIJA Funding

(millions of current dollars)

Program

FY2022

FY2023

FY2024

FY2025

FY2026

Annual Average(FY2022-FY2026) Program Total(FY2022-FY2026)

Total

$8,547

$8,627

$8,647

$8,697

$8,747

$8,653

$43,265

BFP (Assured)

$5,500

$5,500

$5,500

$5,500

$5,500

$5,500

$27,500

BIP (Total)

$3,047

$3,127

$3,147

$3,197

$3,247

$3,153

$15,765

BIP (Assured)

$2,447

$2,487

$2,497

$2,522

$2,547

$2,500

$12,500

BIP (STA)^a

$600

$640

$650

$675

$700

$653

$3,265

Source: FHWA.

).
If the states continue to spend on bridges from their ongoing federal programs at the
FY2021 level, these new IIJA programs would roughly double average annual spending
(unadjusted for inflation) on highway bridges. Adjusting these amounts for expected
inflation using the Congressional Budget Office (CBO) gross domestic product (GDP)
price index for FY2017-FY2032 indicates a substantial loss of purchasing power over the
life of the IIJA. However, most of the increase in new federal bridge spending remains.
Table 3. New Highway Bridge Programs: IIJA Funding
(millions of nominal dollars unless indicated)
Annual Average Program Total
Program
FY2022
FY2023
FY2024
FY2025
FY2026 (FY2022-FY2026) (FY2022-FY2026)
Total
$8,547
$8,627
$8,647
$8,697
$8,747
$8,653
$43,265
BFP (Assured)
$5,500
$5,500
$5,500
$5,500
$5,500
$5,500
$27,500
BIP (Total)
$3,047
$3,127
$3,147
$3,197
$3,247
$3,153
$15,765
BIP (Assured)
$2,447
$2,487
$2,497
$2,522
$2,547
$2,500
$12,500
BIP (STA)
$600
$640
$650
$675
$700
$653
$3,265
Projected Total
$8,086
$7,915
$7,762
$7,656
$7,541
$7,792
$38,960
FY2021$a
Projected
Cumulative %
Loss of
-5%
-8%
-10%
-12%
-14%
-10%
-10%
Purchasing
Power Since start
of FY2022a
Source: FHWA. Projected inflation-adjusted totals reflect the projected value at the end of the year of initial
availability. Most funds are available for obligation for four years. According to FHWA, 84% of obligated funds, on
average, are outlayed in the first three years after obligation.
Notes: BFP = Bridge Formula Program; BIP = Bridge Investment Program; STA = authorized funds subject to BFP = Bridge Formula Program; BIP = Bridge Investment Program; STA = authorized funds subject to
future appropriations. future appropriations. Assured funding refers to multiyear appropriations and Highway Trust Fund (HTF) funded funding refers to multiyear appropriations and Highway Trust Fund (HTF) funded
authorizations, which may be obligated without further appropriations action. HTF funds may be subject to authorizations, which may be obligated without further appropriations action. HTF funds may be subject to
changes to limitations on obligations.changes to limitations on obligations.
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a. Inflation projections based on Congressional Budget Office (CBO), GDP Price Index FY2017-FY2032, in
CBO, The Budget and Economic Outlook: 2022 to 2032. Calculated and adjusted to FY2021=100 by CRS.
a. For annual appropriations of bridge funding, see Table 3. Bridge Formula Program
BFP funds are distributed to states (including the District of Columbia and Puerto Rico) based on BFP funds are distributed to states (including the District of Columbia and Puerto Rico) based on
each stateeach state’'s cost to replace its poor-condition bridges and to rehabilitate its fair-condition bridges, s cost to replace its poor-condition bridges and to rehabilitate its fair-condition bridges,
relative to the total nationwide cost.relative to the total nationwide cost.1423 The IIJA funds the program with $5.5 billion annually over The IIJA funds the program with $5.5 billion annually over
the life of the act. The minimum amount a state will receive is $45 million annually. At least 15% the life of the act. The minimum amount a state will receive is $45 million annually. At least 15%
of each stateof each state’'s funds must be spent on bridges not on the federal-aid system, so-called s funds must be spent on bridges not on the federal-aid system, so-called “"off-off-
system bridges,system bridges,”" and $165 million (3%) is set aside annually for bridges on tribal lands. and $165 million (3%) is set aside annually for bridges on tribal lands.1524 Off- Off-
system bridges, owned by sub-state government entities or federally recognized tribes, are system bridges, owned by sub-state government entities or federally recognized tribes, are
eligible for eligible for a 100% federal share. State DOTs choose the projects, other than for tribal lands 100% federal share. State DOTs choose the projects, other than for tribal lands
bridges. The funds may be used for highway bridge replacement, rehabilitation, preservation, bridges. The funds may be used for highway bridge replacement, rehabilitation, preservation,
protection, or construction projects on any bridge listed in the National Bridge Inventory or any protection, or construction projects on any bridge listed in the National Bridge Inventory or any
new highway bridge that upon completion would be included in the inventory. BFP funds may new highway bridge that upon completion would be included in the inventory. BFP funds may
not be transferred to other programs. This formula program is entirely funded with multiyear not be transferred to other programs. This formula program is entirely funded with multiyear
appropriations from the general fund.appropriations from the general fund.
Bridge Investment Program
The BIP provides competitive grants for bridge replacement, rehabilitation, preservation, or The BIP provides competitive grants for bridge replacement, rehabilitation, preservation, or
resiliency improvements for bridges on the National Bridge Inventory.resiliency improvements for bridges on the National Bridge Inventory.1625 The IIJA authorizes an The IIJA authorizes an
average annual $3.153 billion for the program, of which roughly one-fifth is subject to annual average annual $3.153 billion for the program, of which roughly one-fifth is subject to annual
appropriations. A state or group of states, sub-state governmental entities or groups of such appropriations. A state or group of states, sub-state governmental entities or groups of such
entities, special purpose districts or public authorities that serve a transportation function, entities, special purpose districts or public authorities that serve a transportation function,
metropolitan planning organizations that serve populations over 200,000, federal land metropolitan planning organizations that serve populations over 200,000, federal land
management agencies, tribal governments, or any combination of the aforementioned entities management agencies, tribal governments, or any combination of the aforementioned entities
may apply directly to the U.S. Department of Transportation.may apply directly to the U.S. Department of Transportation.17 BIP grants can be used to replace, BIP grants can be used to replace,
rehabilitate, preserve, or protect (including adding resilience features) bridges or to replace or rehabilitate, preserve, or protect (including adding resilience features) bridges or to replace or
rehabilitate culverts to improve flood control and habitat connectivity for aquatic species. A rehabilitate culverts to improve flood control and habitat connectivity for aquatic species. A
grantee may also use BIP funding to pay subsidy costs of a federal loan under the Transportation grantee may also use BIP funding to pay subsidy costs of a federal loan under the Transportation
Infrastructure Finance and Innovation Act (TIFIA).Infrastructure Finance and Innovation Act (TIFIA).
The program creates three categories of projects for which eligible entities may apply:The program creates three categories of projects for which eligible entities may apply:
 $20 million is set aside annually for planning, feasibility analysis, and revenue $20 million is set aside annually for planning, feasibility analysis, and revenue
forecasting grants. There is no minimum size for planning grants.forecasting grants. There is no minimum size for planning grants.
 Large Bridge Project grants are available for projects with total eligible costs of Large Bridge Project grants are available for projects with total eligible costs of
greater than $100 million. The maximum award may not exceed 50% of the total greater than $100 million. The maximum award may not exceed 50% of the total
eligible project cost, making the minimum award amount $50 million. The award eligible project cost, making the minimum award amount $50 million. The award
may be split into a multiyear award over four consecutive fiscal years.

14 FHWA, Revised Apportionment of Fiscal Year (FY) 2022 Highway Infrastructure Program Funds for the Bridge
Formula Program Pursuant to the Infrastructure Investment and Jobs Act, Notice N 4510.867, April 8, 2022, at
https://www.fhwa.dot.gov/legsregs/directives/notices/n4510867.cfm.
15 23 U.S.C. §202(d).
16 FHWA, “Bridge Investment Program,” at https://www.fhwa.dot.gov/bridge/bip/, updated July 18, 2022.
17 FHWA, “View Grant Opportunity: Bridge Investment Program,” June 10, 2022, at https://www.grants.gov/view-
opportunity.html?dpp=1&oppId=341050.
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 may be split into a multiyear award over four consecutive fiscal years. Bridge Project grants are available for projects with total eligible costs of $100 Bridge Project grants are available for projects with total eligible costs of $100
million or less. The maximum award may not exceed 80% of the total eligible million or less. The maximum award may not exceed 80% of the total eligible
project cost, and the minimum award is $2.5 million.project cost, and the minimum award is $2.5 million.
The IIJA allows up to 5% of BIP funding to be used for eligible projects that consist solely of The IIJA allows up to 5% of BIP funding to be used for eligible projects that consist solely of
culvert replacement or rehabilitation of bridge-sized culverts (as defined under 23 C.F.R. culvert replacement or rehabilitation of bridge-sized culverts (as defined under 23 C.F.R.
§650.305) for flood control or to improve habitat connectivity for aquatic species.§650.305) for flood control or to improve habitat connectivity for aquatic species.
Other sources of federal assistance may be used to satisfy the nonfederal share as long as the total Other sources of federal assistance may be used to satisfy the nonfederal share as long as the total
federal share does not exceed the amount allowable under 23 U.S.C. §120 or 23 U.S.C. §124 for federal share does not exceed the amount allowable under 23 U.S.C. §120 or 23 U.S.C. §124 for
off-system bridges. For a federal land management agency, tribal government, or a consortium of off-system bridges. For a federal land management agency, tribal government, or a consortium of
tribal governments, federal funds made available under non-BIP federal programs (including tribal governments, federal funds made available under non-BIP federal programs (including
Tribal Transportation Program and Federal Lands Transportation Program funds) may be used to Tribal Transportation Program and Federal Lands Transportation Program funds) may be used to
pay the remaining cost of a BIP project.pay the remaining cost of a BIP project.
Federal Lands and Tribal Bridges
Most funding for highways and bridges owned by the federal government or by Indian tribes does Most funding for highways and bridges owned by the federal government or by Indian tribes does
not come from the regularly apportioned programs discussed above. Funding is authorized not come from the regularly apportioned programs discussed above. Funding is authorized
separately, primarily from two stand-alone programs: the Tribal Transportation Program and the separately, primarily from two stand-alone programs: the Tribal Transportation Program and the
Federal Lands Transportation Program.Federal Lands Transportation Program.1826 The Tribal Transportation Program funds are under the The Tribal Transportation Program funds are under the
control of the tribes, in cooperation with the Department of the Interior and the Department of control of the tribes, in cooperation with the Department of the Interior and the Department of
Transportation. The Federal Lands Transportation Program funds are under the control of the Transportation. The Federal Lands Transportation Program funds are under the control of the
federal land management agencies, with assistance and oversight from the Department of federal land management agencies, with assistance and oversight from the Department of
Transportation. A third program, the Federal Lands Access Program, funds facilities that provide Transportation. A third program, the Federal Lands Access Program, funds facilities that provide
access to federal lands. The use of these funds in each state is determined by a state committee access to federal lands. The use of these funds in each state is determined by a state committee
that includes representatives of FHWA, the state DOT, and a political subdivision of the state.that includes representatives of FHWA, the state DOT, and a political subdivision of the state.
Compared with the core highway formula programs, these programs are small. The IIJA Compared with the core highway formula programs, these programs are small. The IIJA provides
provided $602 million annually for the Tribal Transportation Program and $439 million annually for the $602 million annually for the Tribal Transportation Program and $439 million annually for the
Federal Lands Transportation Program. The Federal Lands funding amount is divided among the Federal Lands Transportation Program. The Federal Lands funding amount is divided among the
National Park Service ($346 million), the Fish and Wildlife Service ($36 million), the U.S. Forest National Park Service ($346 million), the Fish and Wildlife Service ($36 million), the U.S. Forest
Service ($26 million), and other federal land management agencies ($31 million). The IIJA Service ($26 million), and other federal land management agencies ($31 million). The IIJA
providesprovided $298 million annually for the Federal Lands Access Program. These three programs $298 million annually for the Federal Lands Access Program. These three programs’
' funds must cover road and bridge needs, and the funds may be used on public transportation funds must cover road and bridge needs, and the funds may be used on public transportation
projects. These programs are paid for from the Highway Trust Fund.projects. These programs are paid for from the Highway Trust Fund.
The IIJA also The IIJA also providesprovided $205 million per year specifically for tribal bridges with funding set aside $205 million per year specifically for tribal bridges with funding set aside
from the larger bridge programs, a sizable increase for tribal bridges annually under prior law, and from the larger bridge programs, a sizable increase for tribal bridges annually under prior law, and
$55 million annually under the National Significant Federal Lands and Tribal Projects Program. $55 million annually under the National Significant Federal Lands and Tribal Projects Program.
The IIJA created several new discretionary highway and bridge grant programs for which tribal The IIJA created several new discretionary highway and bridge grant programs for which tribal
projects are eligible.projects are eligible.
Other Program Sources of Bridge Funding19
Funding Broad sources of highway funding for states to improve their bridges existed prior to the IIJA and Broad sources of highway funding for states to improve their bridges existed prior to the IIJA and
have been continued at increased funding levels. In particular, three of these formula programs—have been continued at increased funding levels. In particular, three of these formula programs—
the Surface Transportation Block Grant Program, the National Highway Performance Program, the Surface Transportation Block Grant Program, the National Highway Performance Program,

18 CRS In Focus IF12129, Tribal Highway and Public Transportation Programs, by William J. Mallett.
19 CRS Report R47022, Federal Highway Programs: In Brief, by Robert S. Kirk (see tables 1 and 2 for a complete
listing of IIJA highway programs).
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and the National Highway Freight Program—together have been the major sources of bridge and the National Highway Freight Program—together have been the major sources of bridge
funding since FY2013 and continue to be available for bridge projects. Funding from other legacy funding since FY2013 and continue to be available for bridge projects. Funding from other legacy
formula programs, such as Transportation Alternatives and the Congestion Mitigation and Air formula programs, such as Transportation Alternatives and the Congestion Mitigation and Air
Quality Improvement Program, also can be used, depending on the specifics of the project. Quality Improvement Program, also can be used, depending on the specifics of the project.
According to FHWA data, in FY2021, $8.6 billion was obligated for bridge projects from all
federal highway program sources (see Table 2). Competitive grant program grants (e.g., from
INFRA) and the Local and Regional Project Assistance Program (also referred to as RAISE
grants) continue to be available for bridge projects. Appalachian Development Highway System
appropriations provided in the IIJA and annual appropriations bills may be used for bridge
projects on that system.
FHWA’ FHWA's Emergency Relief Program
The Emergency Relief Program provides funding for bridges damaged in natural disasters or that The Emergency Relief Program provides funding for bridges damaged in natural disasters or that
are subject to catastrophic failures from an outside source.are subject to catastrophic failures from an outside source.2027 The program provides funds for The program provides funds for
emergency repairs to restore essential travel immediately after the failure to restore essential emergency repairs to restore essential travel immediately after the failure to restore essential
traffic, as well as for longer-term permanent repairs.traffic, as well as for longer-term permanent repairs.
The IIJA changed the time frame within which the federal government will pay 100% of the cost The IIJA changed the time frame within which the federal government will pay 100% of the cost
of emergency repairs from 180 days to 270 days from the date of the disaster. Later repairs, as of emergency repairs from 180 days to 270 days from the date of the disaster. Later repairs, as
well as permanent repairs, such as reconstruction or replacement of a collapsed bridge, are well as permanent repairs, such as reconstruction or replacement of a collapsed bridge, are
reimbursed at the same federal share that would normally apply to the federal-aid highway reimbursed at the same federal share that would normally apply to the federal-aid highway
facility. The IIJA strengthens the language permitting the funding of added protective features to facility. The IIJA strengthens the language permitting the funding of added protective features to
include features that are economically justifiable improvements that will mitigate the risk of include features that are economically justifiable improvements that will mitigate the risk of
recurring damage from extreme weather, flooding, and other natural disasters. The act also adds a recurring damage from extreme weather, flooding, and other natural disasters. The act also adds a
list of eligible protective features under the program.list of eligible protective features under the program.
New Non-bridge Programs That Can Assist Bridge Projects

Francis Scott Key Bridge (Maryland)

In certain circumstances, Congress has provided funding or special conditions for specific emergency relief (ER) projects. The American Relief Act (P.L. 118-58), enacted in December 2024, provided 100% ER funding for response to damage caused by the cargo ship Dali to the Francis Scott Key Bridge in Maryland, less any amounts recovered through compensation, insurance, and other such payments.²⁸

Non-bridge Programs That Can Assist Bridge Projects The IIJA created new formula and competitive grant programs that, while not stand-alone bridge The IIJA created new formula and competitive grant programs that, while not stand-alone bridge
programs, can provide funding for bridge projects, depending on the specifics of the project. programs, can provide funding for bridge projects, depending on the specifics of the project.
Among these programs are the following:Among these programs are the following:
 Promoting Resilient Operations for Transformative, Efficient, and Cost-
saving Transportation saving Transportation (PROTECT) funds can be used for bridge-related funds can be used for bridge-related
infrastructure resilience spending. The IIJA infrastructure resilience spending. The IIJA fundsfunded this new core formula program this new core formula program
at an annual average of $1.46 billion. The act also created a PROTECT at an annual average of $1.46 billion. The act also created a PROTECT
competitive grant program funded at an annual average of $300 million.competitive grant program funded at an annual average of $300 million.
 Rural Surface Transportation Grant Program iswas funded at an annual average funded at an annual average
of $400 million.of $400 million.
 Nationally Significant Projects Program (also referred to as MEGA) is a (also referred to as MEGA) is a
multimodal program designed to fund large, complex transportation multimodal program designed to fund large, complex transportation
infrastructure projects, including highway bridges. The program infrastructure projects, including highway bridges. The program iswas funded at $1 funded at $1
billion annually from multiyear appropriations and authorized to receive an billion annually from multiyear appropriations and authorized to receive an
additional $2 billion annually, subject to appropriation. The program is additional $2 billion annually, subject to appropriation. The program is
administered by the Office of the Secretary of Transportation.administered by the Office of the Secretary of Transportation.
 National Culvert Removal, Replacement, and Restoration Grant Program is is
a multimodal program a multimodal program to be administered by the Office of the Secretary that

20 CRS Report R45298, Emergency Relief for Disaster-Damaged Roads and Public Transportation Systems, by Robert
S. Kirk and William J. Mallett.
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funds projects that improve or restore passage of anadromous fish (such as
salmon). The program is funded at an annual average of $200 million in
multiyear appropriations and authorized at $800 million annually, subject to
appropriations.
Future Bridge Funding Needs
Every two years or so, FHWA assesses the condition and performance of the nation’s highways
administered by the Office of the Secretary that funds projects that improve or restore passage of anadromous fish (such as salmon). The program was funded at an annual average of $200 million in multiyear appropriations and authorized at $800 million annually, subject to appropriations.Annual Appropriated Funds From FY2018 through FY2026, Congress appropriated funding for bridges outside the authorization process (Table 3). This annual appropriation of funds has continued through the period covered by the IIJA. In total, over the nine fiscal years from FY2018 through FY2026, about $5.7 billion was appropriated, an annual average of $633 million (in nominal dollars). Some of these funds were for a competitive bridge program for states with a population density of 100 or fewer per square mile (e.g., Consolidated Appropriations Act, 2018 [P.L. 115-141]). Other amounts were distributed by formula to states for which the percentage of total bridge deck area classified as poor was at least 7.5% (e.g., Consolidated Appropriations Act, 2019 [P.L. 116-6]).²⁹ For these years, Congress in effect pursued a two-pronged approach by making bridges eligible for funding at state discretion under the large highway formula programs established in authorization acts and supplementing these funds with targeted bridge funding in annual appropriations acts. Table 3. Bridge Funding in Annual Appropriations Acts

FY2018-FY2026

Fiscal Year

Amount($ millions)

Legislation

2018

225

Consolidated Appropriations Act, 2018 (P.L. 115-141)

2019

475

Consolidated Appropriations Act, 2019 (P.L. 116-6)

2020

1,150

Further Consolidated Appropriations Act, 2020 (P.L. 116-94)

2021

1,080

Consolidated Appropriations Act, 2021 (P.L. 116-260)

2022

1,145

Consolidated Appropriations Act, 2022 (P.L. 117-103)

2023

1,145

Consolidated Appropriations Act, 2023 (P.L. 117-328)

2024

50

Consolidated Appropriations Act, 2024 (P.L. 118-42)

2025

50

Full-Year Continuing Appropriations and Extensions Act, 2025 (P.L. 119-4)

2026

375

Consolidated Appropriations Act, 2026 (P.L. 119-75)

Total

5,695

NA

Annual Average

633

NA

Source: CRS.

Note: NA = Not applicable.

Bridge Spending History, FY2016-FY2025 Adjusted for inflation, average annual bridge spending (as measured by funding obligations) has been 22% higher in the IIJA period (FY2022-FY2025) to date than under the previous authorization law, the Fixing America's Surface Transportation Act (FAST Act; P.L. 114-94) as extended (FY2016 through FY2021). Average annual spending has been $12.0 billion in the IIJA period to date and $9.8 billion in the FAST Act period (FY2025 dollars). Programmatic funding sources have shifted from highway programs that states or grantees could also use to fund road projects, such as the Surface Transportation Program and the National Highway Performance Program, to other programs dedicated to bridge projects (Figure 2). For more detailed data, see Table A-2.

Figure 2. Trends in Federal Bridge Obligations by Program, FY2016-FY2025

(inflation-adjusted FY2025 dollars)

Source: Federal Highway Administration (FHWA).

Notes: "Other" includes funding from the Bridge Formula Program and Bridge Investment Program. Inflation adjustment by CRS using Bureau of Economic Analysis, Price Indexes for Gross Government Fixed Investment by Type, National Income and Product Accounts Table 5.9.4, Line 40: State and local highways and streets. Weighted average used to approximate fiscal years. Future Bridge Funding Needs Every two years or so, FHWA assesses the condition and performance of the nation's highways and bridges, documents current spending by all levels of government, and estimates future and bridges, documents current spending by all levels of government, and estimates future
spending needs to maintain or improve current conditions and performance.spending needs to maintain or improve current conditions and performance.2130 As with any attempt As with any attempt
to forecast future conditions, a host of simplifying assumptions, omissions, and data problems to forecast future conditions, a host of simplifying assumptions, omissions, and data problems
influence these estimates. Among other things, the estimates rely on forecasts of travel demand. influence these estimates. Among other things, the estimates rely on forecasts of travel demand.
Despite such uncertainties and assumptions, these estimates provide a way to assess the level of Despite such uncertainties and assumptions, these estimates provide a way to assess the level of
current spending compared with what would be needed in the future under different scenarios. current spending compared with what would be needed in the future under different scenarios.
Because of the modeling involved, FHWABecause of the modeling involved, FHWA’'s future needs estimates for bridges are limited to s future needs estimates for bridges are limited to
fixing deficiencies in existing bridges only when the benefits outweigh the costs.fixing deficiencies in existing bridges only when the benefits outweigh the costs.
The most recent assessment was published in The most recent assessment was published in 20212024 based on based on 20162014-2018 data. Represented in data. Represented in 2021
2024 dollars, this assessment showed that dollars, this assessment showed that $17.2an annual average of $20.4 billion was spent on bridge rehabilitation or billion was spent on bridge rehabilitation or
replacement by governments at all levels replacement by governments at all levels in 2016from 2014 to 2018. An additional $1. An additional $1.9 billion billion-$2 billion per year was spent on the was spent on the
construction of new bridges.construction of new bridges.2231 It estimated that fixing all bridge deficiencies existing in It estimated that fixing all bridge deficiencies existing in 2016
2018 would cost $would cost $148248 billion (in billion (in 20212024 dollars). This figure is dollars). This figure is almost nine12 times the level of spending times the level of spending
on bridge rehabilitation and replacement in on bridge rehabilitation and replacement in 2016.23
2014-2018.³² Of course, fixing all deficient bridges overnight is not feasible. FHWA, therefore, estimated how Of course, fixing all deficient bridges overnight is not feasible. FHWA, therefore, estimated how
this investment backlog may change at various levels of spending during this investment backlog may change at various levels of spending during 2017-20362019-2038, taking into , taking into
account the deterioration of existing bridges over that period. The results of this analysis are seen account the deterioration of existing bridges over that period. The results of this analysis are seen
inin Figure 23. FHWA estimated that eliminating the backlog by FHWA estimated that eliminating the backlog by 20362038 would require an investment would require an investment
of $28.of $28.19 billion annually (in billion annually (in 20212024 dollars).

Figure 3. Estimated Effect of Various Spending Levels on Bridge Investment Backlog

(average annual spending for 20 years)

Source: U.S. Department of Transportation, FHWA, and Federal Transit Administration, Status of the Nation's Highways, Bridges, and Transit: Conditions and Performance Report to Congress, 25^th ed., 2024, exhibit 10-20, https://www.fhwa.dot.gov/policy/25cpr/.

Notes: The current funding level is the annual average from 2014 to 2018, and the 20-year spending scenarios are for 2019 through 2038. CRS adjusted the data expressed in 2018 dollars to 2024 dollars using Bureau of Economic Analysis, Price Indexes for Gross Government Fixed Investment by Type, National Income and Product Accounts Table 5.9.4, Line 40: State and local highways and streets.

The IIJA provided an increase in federal highway funding overall and created new dedicated bridge funding programs dollars).
The IIJA provided an increase in federal highway funding overall and created new dedicated
bridge funding programs that provide an annual average of $7.8 billion (in 2021 dollars) (Table
3)(Table 2). If states . If states decidewere to commit the same amount of to commit the same amount of their general federal highway funding to federal highway funding to
bridges as they did in bridges as they did in FY2021, about $8.6 billion, total federal FY2022-FY2025, an average of about $11.7 billion annually (in 2024 dollars), total funding committed to bridges funding committed to bridges
would be about $would be about $16.424.9 billion annually billion annually. Assuming (in 2024 dollars). This assumes that state and local funds that state and local funds would continue to provide continue to provide
53% of all bridge spending53% of all bridge spending, as has been the case in recent years, total bridge spending could
amount to around $34.8 billion per year (in 2021 dollars) under the IIJA.24
This bridge spending estimate does not take into account the increase in funding for general
highway programs in the IIJA or the improved opportunity for accessing competitive grant
programs for bridge projects. Even so, the funding amounts in the IIJA could conceivably allow
for total spending for five years at the level FHWA estimates would be needed to eliminate bridge

21 The “maintain” scenario assumes that capital investment changes so that selected measures of bridge performance in
2036 are maintained at their 2016 levels. The “improve” scenario is the level of spending in which the investment is
made in all projects by 2036 for which the economic benefits are equal to or greater than the economic costs.
22 U.S. Department of Transportation, FHWA, and Federal Transit Administration, Status of the Nation’s Highways,
Bridges, and Transit: Conditions and Performance Report to Congress, 24th ed., pp. 2-17, October 2021, at
https://doi.org/10.21949/1521794.
23 Ibid., exhibit 10-15.
24 The historical estimate of the state and local share of highway capital outlays is taken from Congressional Budget
Office, Public Spending on Transportation and Water Infrastructure, 1956 to 2017, supplemental tables 1, 2, and 6, at
https://www.cbo.gov/publication/54539.
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Highway Bridges: Conditions, Funding Programs, and Issues for Congress

deficiencies if continued over 20 years (i.e., $28.1 billion per year), and have $6.7 billion per year
available for the construction of new bridges. However, as state and local governments make
most of the decisions concerning which projects to pursue and, within the limits of federal
matching share requirements, how much of their own money to commit, it is uncertain whether
total bridge spending will achieve this level.
Figure 2. Estimated Effect of Various Spending Levels on Bridge Investment Backlog
(Average annual spending for 20 years)

Source: U.S. Department of Transportation, FHWA, and Federal Transit Administration, Status of the Nation’s
Highways, Bridges, and Transit: Conditions and Performance Report to Congress, 24th ed., October 2021, exhibit 10-15.
Notes: The current funding level is for 2016, and the 20-year spending scenarios are for 2017 through 2036.
CRS adjusted the data expressed in 2016 dollars to 2021 dollars using the implicit GDP deflator.
Issues for Congress
The IIJA replaced the former policy of gradual improvement of the nation’s bridges with a more
ambitious program to speed up the pace of bridge improvements. The implementation of this
policy and its success in improving bridge conditions are likely to be of ongoing concern to
Congress.
Loss of Purchasing Power
Because inflation was low for many years, it was not an issue during the reauthorization debate
that preceded passage of the IIJA. However, more rapid price rises since early 2020 have raised
the prospect that inflation may erode the value of the increased bridge spending provided in the
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IIJA. Inflation projections by CBO suggest that the funds authorized and appropriated in the IIJA
could lose 10% of their purchasing power over the period FY2022-FY2026. 25
The loss of purchasing power could be greater than this, given that indexes of highway
construction costs have risen faster over the last five years than the measure used by CBO.26
Another factor that could make the impact of inflation more severe is the way funding for
highways is distributed and managed. Each year’s federal highway funds are made available for
obligation for four years. Obligation occurs when the state or grantee signs a project agreement
with FHWA in which FHWA commits to the federal portion of the project cost. According to
FHWA, 84% of funds are spent within three years of obligation, but some funds take as long as
nine years to expend.27 The time involved in expending authorized funds could make the loss in
purchasing power greater than indicated in Table 3.
Programmatic Substitution
Given as has been the case in recent years.³³ If this funding level were to continue over 20 years, the bridge investment backlog would be reduced by about 90%, according to FHWA estimates. Additional funding would be needed for the construction of new bridges. As state and local governments make most of the decisions concerning which projects to pursue and, within the limits of federal matching share requirements, how much of their own money to commit, it is uncertain whether total bridge spending will achieve this level. Issues for Congress

The IIJA replaced the former policy of gradual improvement of the nation's bridges with a more ambitious program to speed up the pace of bridge improvements. Evaluations of the implementation of this policy and its success in improving bridge conditions are likely to be of concern to Congress in a reauthorization of the surface transportation programs.

Bridge Funding Programs

The overall level of highway infrastructure funding and the amount dedicated to bridges by Congress is likely to be an issue in reauthorization of federal highway programs after the expiration of IIJA. IIJA created two new bridge funding programs and provided most of the funding as multiyear advanced appropriations from the Treasury general fund. Congress might decide to continue these programs with general funds or switch the funding source to the HTF. Alternatively, Congress might decide not to reauthorize these dedicated bridge programs, thereby allowing states to decide whether or not to use federal highway funds for bridge projects.

The collapse of the Francis Scott Key Bridge in Baltimore, MD, as a result of a vessel strike has highlighted the vulnerability of some bridges to cargo ships.³⁴ Although the cost of reducing these vulnerabilities to an acceptable level is unknown, anecdotal evidence suggests the cost might be high relative to current resources, especially resources available at the state and local levels. Congress could provide funding dedicated to reducing these vulnerabilities, either as a set-aside from existing bridge programs or as a new program. Another option is that Congress could require state and local bridge owners to reduce these vulnerabilities to an acceptable level with current federal and nonfederal funding.

Congress could consider whether the Harbor Maintenance Trust Fund (HMTF) is an appropriate funding source to provide navigation safety features at bridges in the navigation channel, such as dolphins or bumpers and fenders protecting bridge piers from vessel strikes.³⁵ Such projects would require an appropriation and legislative change in the types of projects supported by HMTF expenditures. These actions could be controversial because of their effect on the funding of existing types of projects that support HMTF taxpayers, primarily importers of waterborne cargo. Another issue might be the agency responsible for implementing navigation safety features at bridges. Many HMTF-funded projects—maintenance dredging, breakwater and jetty maintenance, and construction and operation of dredged material disposal facilities—are directly carried out by the Army Corps of Engineers.³⁶ By contrast, highway bridge projects, even if supported by federal funds, are typically carried out by state and local governments. Type of Funding Distribution Another potential issue could be the manner in which funding is distributed. In the IIJA, Congress created several competitive surface transportation funding programs, including one specifically for bridge projects. A rationale for these programs is to concentrate relatively large sums of funding on projects that may have significant national and regional benefits. In some cases, project sponsors have had difficulty funding these projects from federal formula funds, federal loans, and nonfederal sources. Consequently, some older and obsolete bridges have continued to serve vehicular traffic but less reliably and safely than might otherwise be possible.

Compared with formula funding, competitive funding places a greater administrative burden on project sponsors and is not guaranteed. Given the interest in "extra" federal funding among project sponsors, many applications are likely to be unsuccessful. For example, there were 33 eligible applications for large bridge funding under the FY2024 BIP. Of these 33 applications, FHWA recommended funding for 13 projects.³⁷

Nonfederal Funding for Bridges Another criticism of federal funding, especially competitive funding, is that it may substitute for nonfederal funding. Thus, in some cases, for example, a large competitive federal grant might replace nonfederal funding, such as a new or higher user fee. Research by CBO has estimated that state and local governments that receive federal grants for highway projects "reduce their own per capita spending on highway capital by 26 cents for an additional dollar of annual federal formula grants."³⁸ This raises the possibility that more federal funding will lead to less combined state and federal spending on highway bridges than previous state and local spending patterns imply. Furthermore, given the large increase in bridge spending from bridge-only programs, states may choose to rely the large increase in bridge spending from bridge-only programs, states may choose to rely
mainly on BFP and BIP to fund bridge projects and use a greater share of their core formula funds mainly on BFP and BIP to fund bridge projects and use a greater share of their core formula funds
on non-bridge highway projects. This could result in the net increase in spending on bridges being on non-bridge highway projects. This could result in the net increase in spending on bridges being
less than Congress may have assumed in enacting the IIJA.
Maintenance of Effort
Research by CBO has estimated that state and local governments that receive federal grants for
highway projects “reduce their own per capita spending on highway capital by 26 cents for an
additional dollar of annual federal formula grants.”28 This raises the possibility that the IIJA will
lead to less combined state and federal spending on highway bridges than previous state and local
spending patterns imply.
Tolling of Non-tolled Bridges
less than Congress may have intended.

Possible options for Congress include imposing maintenance-of-effort requirements on bridge spending, although these would reduce funding flexibility at the state and local level, and can be difficult to enforce.³⁹ Another option for Congress is to lower the maximum federal share of bridge project funding. The maximum federal share for a large bridge project (defined as a project of $100 million or more) in the BIP was 50%, lower than for most highway and bridge projects administered by FHWA. A relatively low matching share could inhibit state and local governments from pursuing bridge projects.

Another consideration is the effect of federal funding on the use by state and local governments of bridge tolling. Wider use of tolling could allow for more rapid improvement of major bridges. Heavily traveled Wider use of tolling could allow for more rapid improvement of major bridges. Heavily traveled
bridges can be attractive targets for conversion to toll facilities—many bridges have no bridges can be attractive targets for conversion to toll facilities—many bridges have no
convenient alternatives, so drivers may find it difficult to avoid paying whatever toll is imposed. convenient alternatives, so drivers may find it difficult to avoid paying whatever toll is imposed.
In some cases, tolling authorities offer relief for certain drivers, such as those with income below a certain threshold.⁴⁰ The revenue stream provided by tolls can make bridge building and reconstruction an attractive The revenue stream provided by tolls can make bridge building and reconstruction an attractive
investment for private entities that are interested in participating in a public-private partnership. investment for private entities that are interested in participating in a public-private partnership.
Tolling can also help projects become eligible for a TIFIA loan that requires a dedicated revenue Tolling can also help projects become eligible for a TIFIA loan that requires a dedicated revenue
stream for repayment.stream for repayment.2941 Currently, any toll-free federal-aid highway bridge may be converted to Currently, any toll-free federal-aid highway bridge may be converted to

25 CBO, Budget and Economic Outlook: 2022-2032, June 2022, at https://www.cbo.gov/data/budget-economic-data#7.
26 For FY2017-FY2020, the U.S. Bureau of Economic Analysis Highways and Streets index rose an average of 4.25%
more than CBO gross domestic product (GDP) projections. For FY2017-FY2021, the National Highway Construction
Cost Index exceeded the CBO GDP index by an average of 2.4% per year.
27 FHWA, Funding Federal Aid Highways, “Outlay of Funding,” January 2017, at https://www.fhwa.dot.gov/policy/
olsp/fundingfederalaid/06.cfm.
28 Sheila Campbell and Chad Shirley, Fiscal Substitution in Spending for Highway Infrastructure, CBO, Working
Paper 2021-13, October 2021, pp. 1-45, at https://www.cbo.gov/publication/57430. The report notes that their finding
is at the lower end of estimates in existing literature.
29 CRS Report R44910, Tolling U.S. Highways and Bridges, by Robert S. Kirk.
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tolling and receive federal highway aid if the conversion is related to the reconstruction or tolling and receive federal highway aid if the conversion is related to the reconstruction or
replacement of the bridge. Also, new bridges may be tolled.replacement of the bridge. Also, new bridges may be tolled.30
42 The large increase in The large increase in IIJA bridge funding could on the one hand lessen the use of tolling as a bridge funding could on the one hand lessen the use of tolling as a
financing option, given that bridge tolls are often unpopular. On the other hand, the IIJA financing option, given that bridge tolls are often unpopular. On the other hand, the IIJA provides
provided $50 million annually to the Congestion Relief Program for congestion solutions, including the $50 million annually to the Congestion Relief Program for congestion solutions, including the
imposition of tolls for congestion pricing. Congress may want to imposition of tolls for congestion pricing. Congress may want to explore whether the IIJA has
consider how federal funding programs affected the use of tolls to fund construction or reconstruction of bridges.affected the use of tolls to fund construction or reconstruction of bridges.
Spending on Off-System Bridges
Historically, nearly all federal highway funding was restricted to roads and bridges on the federal-Historically, nearly all federal highway funding was restricted to roads and bridges on the federal-
aid highway system. Highway bridges have been the main exception to the rule. A minimum level aid highway system. Highway bridges have been the main exception to the rule. A minimum level
of spending on off-system bridges, which typically carry much less traffic than bridges on the of spending on off-system bridges, which typically carry much less traffic than bridges on the
federal-aid system, has been required in every highway authorization bill since 1978.federal-aid system, has been required in every highway authorization bill since 1978.
Congress’ Congress's interest in funding off-system bridges was affirmed under the IIJA. The existing off-s interest in funding off-system bridges was affirmed under the IIJA. The existing off-
system bridge spending requirements were continued and the set-aside for off-system projects has system bridge spending requirements were continued and the set-aside for off-system projects has
been strongly supported by predominantly rural states and by many county and municipal been strongly supported by predominantly rural states and by many county and municipal
governments. The policy could be an issue if it constrains resources available to repair or replace governments. The policy could be an issue if it constrains resources available to repair or replace
more heavily traveled bridges on major roads.

30 The exception to the reconstruction or replacement requirement would be to convert all or some of the bridge lanes to
a congestion pricing facility under the Value Pricing Pilot Program.
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Appendix.
more heavily traveled bridges on major roads. Appendix. Table A-1. Bridge Condition by State and Territory
(data as of June 15, (data as of June 15, 2021)
All
2025)

State

All Bridges (number)

Condition Rating (number)
Condition Rating (percentage)
Bridges
State
(number)
Good
Fair
Poor
Good
Fair
Poor
Alabama
16,164
6,550
9,028
586
40.5
55.9
3.6
Alaska
1,632
716
782
134
43.9
47.9
8.2
Arizona
8,467
5,275
3,075
117
62.3
36.3
1.4
Arkansas
12,941
6,234
6,028
679
48.2
46.6
5.2
California
25,737
12,224
12,020
1,493
47.5
46.7
5.8
Colorado
8,869
3,063
5,337
469
34.5
60.2
5.3
Connecticut
4,361
1,249
2,881
231
28.6
66.1
5.3
Delaware
875
291
567
17
33.3
64.8
1.9
Dist. of Columbia
246
74
165
7
30.1
67.1
2.8
Florida
12,680
8,052
4,169
459
63.5
32.9
3.6
Georgia
14,987
11,054
3,614
319
73.8
24.1
2.1
Hawaii
1,162
265
810
87
22.8
69.7
7.5
Idaho
4,561
1,322
3,001
238
29.0
65.8
5.2
Illinois
26,846
12,848
11,593
2,405
47.9
43.2
9.0
Indiana
19,337
7,866
10,389
1,082
40.7
53.7
5.6
Iowa
23,870
9,354
10,012
4,504
39.2
41.9
18.9
Kansas
24,925
13,335
10,313
1,277
53.5
41.4
5.1
Kentucky
14,410
4,089
9,331
990
28.4
64.8
6.9
Louisiana
12,782
5,931
5,220
1,631
46.4
40.8
12.8
Maine
2,485
728
1,443
314
29.3
58.1
12.6
Maryland
5,446
1,789
3,404
253
32.8
62.5
4.6
Massachusetts
5,245
1,321
3,468
456
25.2
66.1
8.7
Michigan
11,284
4,091
5,953
1,240
36.3
52.8
11.0
Minnesota
13,496
7,857
5,021
618
58.2
37.2
4.6
Mississippi
16,788
9,921
5,693
1,174
59.1
33.9
7.0
Missouri
24,590
9,654
12,718
2,218
39.3
51.7
9.0
Montana
5,266
1,600
3,301
365
30.4
62.7
6.9
Nebraska
15,348
7,966
6,102
1,280
51.9
39.8
8.3
Nevada
2,067
1,070
968
29
51.8
46.8
1.4
New Hampshire
2,527
1,344
989
194
53.2
39.1
7.7
New Jersey
6,798
1,809
4,507
482
26.6
66.3
7.1
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All
Condition Rating (number)
Condition Rating (percentage)
Bridges
State
(number)
Good
Fair
Poor
Good
Fair
Poor
New Mexico
4,025
1,466
2,351
208
36.4
58.4
5.2
New York
17,555
6,355
9,528
1,672
36.2
54.3
9.5
North Carolina
18,877
7,840
9,712
1,325
41.5
51.4
7.0
North Dakota
4,285
2,046
1,758
481
47.7
41.0
11.2
Ohio
27,151
16,493
9,324
1,334
60.7
34.3
4.9
Oklahoma
23,220
9,898
11,026
2,296
42.6
47.5
9.9
Oregon
8,235
2,800
5,053
382
34.0
61.4
4.6
Pennsylvania
23,166
7,705
12,263
3,198
33.3
52.9
13.8
Rhode Island
779
168
475
136
21.6
61.0
17.5
South Carolina
9,395
4,142
4,754
499
44.1
50.6
5.3
South Dakota
5,886
1,943
2,925
1018
33.0
49.7
17.3
Tennessee
20,331
8,689
10,801
841
42.7
53.1
4.1
Texas
55,175
27,807
26,579
789
50.4
48.2
1.4
Utah
3,056
1,005
1,988
63
32.9
65.1
2.1
Vermont
2,836
1,494
1,274
68
52.7
44.9
2.4
Virginia
13,997
4,644
8,823
530
33.2
63.0
3.8
Washington
8,358
4,331
3,626
401
51.8
43.4
4.8
West Virginia
7,314
1,719
4,105
1,490
23.5
56.1
20.4
Wisconsin
14,307
7,289
6,031
987
50.9
42.2
6.9
Wyoming
3,114
920
1,964
230
29.5
63.1
7.4
Guam
10
2
6
2
20.0
60.0
20.0
Puerto Rico
2,334
426
1,626
282
18.3
69.7
12.1
U.S. Virgin Islands
24
4
14
6
16.7
58.3
25.0
Total
619,622
278,128
297,908
43,586
44.9
48.1
7.0
Source: Federal Highway Administration (FHWA), National Bridge Inventory, “

Good

Fair

Poor

Good

Fair

Poor

Alabama

16,181

5,801

9,835

545

35.9

60.8

3.4

Alaska

1,660

766

770

124

46.1

46.4

7.5

Arizona

8,587

5,430

3,062

95

63.2

35.7

1.1

Arkansas

12,978

5,770

6,513

695

44.5

50.2

5.4

California

25,975

12,239

12,452

1,284

47.1

47.9

4.9

Colorado

8,990

3,035

5,538

417

33.8

61.6

4.6

Connecticut

4,363

1,210

2,944

209

27.7

67.5

4.8

Delaware

874

376

488

10

43.0

55.8

1.1

Dist. of Columbia

261

90

166

5

34.5

63.6

1.9

Florida

13,070

7,705

5,005

360

59.0

38.3

2.8

Georgia

15,090

10,876

3,951

263

72.1

26.2

1.7

Hawaii

1,180

461

652

67

39.1

55.3

5.7

Idaho

4,646

1,468

2,928

250

31.6

63.0

5.4

Illinois

26,927

12,012

12,352

2,563

44.6

45.9

9.5

Indiana

19,542

8,213

10,286

1,043

42.0

52.6

5.3

Iowa

23,716

9,329

9,964

4,423

39.3

42.0

18.6

Kansas

24,891

12,966

10,624

1,301

52.1

42.7

5.2

Kentucky

14,590

3,916

9,586

1,088

26.8

65.7

7.5

Louisiana

12,684

4,802

6,459

1,423

37.9

50.9

11.2

Maine

2,542

637

1,513

392

25.1

59.5

15.4

Maryland

5,500

1,753

3,507

240

31.9

63.8

4.4

Massachusetts

5,311

1,291

3,519

501

24.3

66.3

9.4

Michigan

11,397

3,778

6,369

1,250

33.1

55.9

11.0

Minnesota

13,551

7,636

5,306

609

56.4

39.2

4.5

Mississippi

16,711

9,070

6,674

967

54.3

39.9

5.8

Missouri

24,647

9,180

13,304

2,163

37.2

54.0

8.8

Montana

5,235

1,682

3,165

388

32.1

60.5

7.4

Nebraska

15,412

8,169

6,088

1,155

53.0

39.5

7.5

Nevada

2,123

1,200

901

22

56.5

42.4

1.0

New Hampshire

2,549

1,303

1054

192

51.1

41.3

7.5

New Jersey

6,825

1,732

4,701

392

25.4

68.9

5.7

New Mexico

4,033

1,356

2,505

172

33.6

62.1

4.3

New York

17,666

5,698

10,227

1,741

32.3

57.9

9.9

North Carolina

19,343

8,800

9,161

1,382

45.5

47.4

7.1

North Dakota

4,250

1,782

1,998

470

41.9

47.0

11.1

Ohio

26,713

16,242

9,205

1,266

60.8

34.5

4.7

Oklahoma

22,926

9,515

11,692

1,719

41.5

51.0

7.5

Oregon

8,329

2,645

5,262

422

31.8

63.2

5.1

Pennsylvania

23,314

8,019

12,482

2,813

34.4

53.5

12.1

Rhode Island

787

196

481

110

24.9

61.1

14.0

South Carolina

9,504

3,568

5,334

602

37.5

56.1

6.3

South Dakota

5,883

2,038

2,900

945

34.6

49.3

16.1

Tennessee

20,374

8,620

10,867

887

42.3

53.3

4.4

Texas

56,951

29,423

26,848

680

51.7

47.1

1.2

Utah

3,144

659

2,376

109

21.0

75.6

3.5

Vermont

2,866

1,348

1,404

114

47.0

49.0

4.0

Virginia

14,143

4,609

9,049

485

32.6

64.0

3.4

Washington

8,520

4,343

3,704

473

51.0

43.5

5.6

West Virginia

7,345

1,960

4,078

1,307

26.7

55.5

17.8

Wisconsin

14,498

6,749

6,773

976

46.6

46.7

6.7

Wyoming

3,138

895

2,019

224

28.5

64.3

7.1

Guam

NA

NA

NA

NA

NA

NA

NA

Puerto Rico

2,434

414

1,676

344

17.0

68.9

14.1

U.S. Virgin Islands

24

4

12

8

16.7

50.0

33.3

Total

624,193

272,779

309,729

41,685

43.7

49.6

6.7

Source: Federal Highway Administration (FHWA), National Bridge Inventory, "Bridge Condition by Functional Bridge Condition by Functional
Classification, Classification, 2021,” at 2025," https://www.fhwa.dot.gov/bridge/https://www.fhwa.dot.gov/bridge/fc.cfm.

Note: Data for Guam for 2025 are unavailable.

fc.cfm.

Congressional Research Service

16

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Table A-2. Bridge Obligations by Program: FY2015-FY2021
(, FY2016-FY2025 (millions of current dollars)current dollars)
Total
FY2015-
Program
FY2015
FY2016
FY2017

FY2017

FY2018
FY2019
FY2020
FY2021
FY2021
Interstate Maintenance
11,385,907
2,406,944
2,305,999
8,908,364
2,240,105
13,272,298
9,477,424
49,997,043
National Highway Sys.
55,928,169
37,274,844
29,941,503
26,125,570
20,040,402
3,527,492
23,401,906
196,239,887
Surface Transport. Prog.
2,254,453,670 2,409,636,416
2,107,910,876
2,566,044582
2,515,966,628
2,316,890,215
2,173,135,549 16,344,037,666
Nat. High. Perf. Prog.
3,638,484,037
3,910,107,620
3,936,571913
3,789,511,563
4,032,500,809
4,171,434,995
3,997,708,956 27,476,499,892
Nat. High. Freight Prog.
—
237,121,333
106,864,872
260,926,616
155,729,020
273,439,100
146,527,328
1,180,608,268
Transport. Alternatives
2,368,351
6,332,735
3,967,287
3,562,061
7,840,507
4,620,312
25,406,477
54,097,730
Bridge Programs
243,314,396
79,924,642
71,802,855
43,968,419
2,091,860
55,980,591
(38,274,968)
458,807,795
Cong. Mit. & Air Quality
62,542,855
38,121,580
44,430,292
31,197,678
30,500,730
22,739,297
38,935,285
268,467,717
Appalach. Dev. High. Sys.
51,015,156
158,589,439
63,980,429
(586,007)
10,843,215
(3,839,007)
16,112,142
296,115,367
High Priority Projects
10,125,976
17,908,671
15,770,437
13,463,004
6,370,325
3,613,582
14,115,583
81,367,578
Min. Guar.—TEA-21
10,404,647
10,711,287
1,828,744
(266,006)
(2,089,107)
200,855
(1,784,047)
19,006,374
Equity Bonus Exempt
211,958,856
8,778,554
16,978,609
4,605,487
7,038,169
12,624,969
8,089,598
270,074,242
Coord. Bord, Infra. Prog.
2,569,474
3,142,320
6,169,284
(232,028)
(1,000,000)
105,999
—
4,470,410
Safe Routes to School
694,649
—
—
(24,133)
—
—
—
670,516
Planning and Research
—
—
—
130,043
151,500
—
132,140
413,682
CRRSAA
—
—
—
—
—
—
262,853,966
262,853,966
All Others
248,261,223
181,235,160
257,267,156
344,279,171
576,427,938
922,323,453
1,893,522,594
4,423,316,695
Total
6,803,507,637
7,095,006,638
6,665,970,255
7,091,614,385
7,364,652,101
7,796,934,150
8,569,359,933 51,387,044,829
Source: FHWA.
Notes: Displays funds from the Fixing America’s Surface Transportation Act (FAST Act; P.L. 114-94), as extended, as well as ongoing obligation of funds from earlier
authorization acts.

FY2019

FY2020

FY2021

FY2022

FY2023

FY2024

FY2025

Interstate Maintenance

$2

$2

$9

$2

$13

$9

$2

($0)

$3

($10)

National Highway System

$37

$30

$26

$20

$4

$23

$7

$8

($1)

$13

Surface Transportation Program

$2,410

$2,108

$2,566

$2,516

$2,317

$2,173

$2,965

$2,557

$2,580

$2,167

National Highway Performance Program

$3,910

$3,937

$3,790

$4,033

$4,171

$3,998

$4,157

$3,608

$3,649

$3,877

National Highway Freight Program

$237

$107

$261

$156

$273

$147

$179

$184

$289

$246

Transportation Alternatives

$6

$4

$4

$8

$5

$25

$14

$8

$12

$9

Bridge Programs

$80

$72

$44

$2

$56

($38)

$12

$2

($2)

$2

Congestion Mitigation & Air Quality

$38

$44

$31

$31

$23

$39

$62

$62

$57

$28

Appalachian Development Highway System

$159

$64

($1)

$11

($4)

$16

$19

$13

($0)

$0

High Priority Projects

$18

$16

$13

$6

$4

$14

$13

$1

$2

($0)

Minimum Guarantee, TEA-21

$11

$2

($0)

($2)

$0

($2)

$2

($0)

($4)

($0)

Equity Bonus Exempt

$9

$17

$5

$7

$13

$8

$10

$1

$10

($4)

Coordinated Border Infrastructure Program

($3)

$6

($0)

($1)

$0

$0

($0)

($0)

$0

$0

Safe Routes to School

$0

$0

($0)

$0

$0

$0

$0

$0

$0

$0

Planning and Research

$0

($0)

$0

$0

$0

$0

$0

$0

$0

$0

CRRSAA

$0

$0

$0

$0

$0

$263

$234

$443

($6)

$1

Carbon Reduction Program

$0

$0

$0

$0

$0

$0

$1

$5

$21

$15

PROTECT Formula Program

$0

$0

$0

$0

$0

$0

$98

$132

$57

$87

All Other

$181

$257

$344

$576

$922

$1,894

$2,163

$4,085

$5,729

$6,621

Total

$7,095

$6,666

$7,092

$7,365

$7,797

$8,569

$9,938

$11,110

$12,396

$13,051

Source: FHWA. Notes: CRRSAA = Coronavirus Response and Relief Supplemental Appropriations Act, 2021 (P.L. 116-260); TEA-21 = Transportation Equity Act for the CRRSAA = Coronavirus Response and Relief Supplemental Appropriations Act, 2021 (P.L. 116-260); TEA-21 = Transportation Equity Act for the 21st
21^st Century (P.L. 105-178). Totals may not add due to rounding. Amounts in parentheses indicate net de-obligations during the fiscal year.Century (P.L. 105-178). Totals may not add due to rounding. Amounts in parentheses indicate net de-obligations during the fiscal year.
CRS-17

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Highway Bridges: Conditions, Funding Programs, and Issues for Congress




Author Information

Robert S. Kirk
William J. Mallett
Specialist in Transportation Policy
Specialist in Transportation Policy




Disclaimer
This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan
shared staff to congressional committees and Members of Congress. It operates solely at the behest of and
under the direction of Congress. Information in a CRS Report should not be relied upon for purposes other
than public understanding of information that has been provided by CRS to Members of Congress in
connection with CRS’s institutional role. CRS Reports, as a work of the United States Government, are not
subject to copyright protection in the United States. Any CRS Report may be reproduced and distributed in
its entirety without permission from CRS. However, as a CRS Report may include copyrighted images or
material from a third party, you may need to obtain the permission of the copyright holder if you wish to
copy or otherwise use copyrighted material.

Congressional Research Service
R47194 · VERSION 1 · NEW
18

Robert S. Kirk, retired CRS Specialist in Transportation Policy, contributed to an earlier version of this report.

Footnotes

1.

National Transportation Safety Board (NTSB), Collapse of the Fern Hollow Bridge, Highway Investigation Report HIR-24-02, February 21, 2024, https://www.ntsb.gov/investigations/AccidentReports/Reports/HIR2402.pdf.

2.

Federal Highway Administration (FHWA), National Bridge Inventory, "Bridge Condition by Owner, 2025," https://www.fhwa.dot.gov/bridge/nbi/no10/owner25.cfm.

3.

Arterials, including Interstates, are roads designed to provide for relatively long trips at high speed and usually have multiple lanes and limited access. Principal arterials exclude rural and urban minor arterials. FHWA, National Bridge Inventory, "Bridge Condition by Functional Classification, 2025," https://www.fhwa.dot.gov/bridge/fc.cfm.

4. FHWA, National Bridge Inventory, "Bridge Condition by Functional Classification, Average Daily Travel (ADT), 2025," https://www.fhwa.dot.gov/bridge/fc.cfm. 5.

The National Bridge Inspection Program was initiated in 1968 following the 1967 collapse of the so-called Silver Bridge over the Ohio River. The National Bridge Inspection Standards were first issued in 1971. See FHWA, "Tables of Frequently Requested NBI Information," http://www.fhwa.dot.gov/bridge/britab.cfm.

6.

23 C.F.R. §650, subpart C.

7.

A nonredundant steel tension member is a primary steel member in tension, or with a tension element, whose failure would probably cause a portion of or the entire bridge to collapse. A nonredundant steel tension member was previously known in regulation as a fracture critical member.

8.

FHWA, National Bridge Inventory, "Bridge Condition by Posting Status, 2025," https://www.fhwa.dot.gov/bridge/nbi/posting.cfm.

9.

Interstates are the highest class of roadways in FHWA's functional classification system, and local roads are the lowest.

10. FHWA, "Seismic and Multi-Hazard Resilience," https://www.fhwa.dot.gov/bridge/seismic/. Although not considered in this report, bridges are also vulnerable to nefarious actions, including terrorism. For more information, see CRS Report R48878, Critical Infrastructure: Emerging Trends and Policy Considerations for Congress, by Brian E. Humphreys. 11.

CRS Report R41746, Earthquake Risk and U.S. Highway Infrastructure: Frequently Asked Questions, by William J. Mallett, Nicole T. Carter, and Peter Folger.

12.

According to NTSB, a vulnerability assessment is "a mathematical risk model calculated using data on bridge/span geometry and design, pier protection and lateral capacity, the characteristics of vessel traffic transiting the main navigation channel, waterway characteristics, and other factors." NTSB, Safeguarding Bridges from Vessel Strikes: Need for Vulnerability Assessment and Risk Reduction Strategies, MIR-25-10, March 18, 2025, p. 1, https://www.ntsb.gov/investigations/AccidentReports/Reports/MIR2510.pdf (hereinafter, NTSB, Safeguarding Bridges).

13.

NTSB, Safeguarding Bridges, pp. 1-2.

14.

NTSB, Safeguarding Bridges, p. 2.

15.

NTSB, "Summary of Bridge Owner Responses to Safety Recommendations H-25-3 and H-25-4," updated November 25, 2025, https://www.ntsb.gov/Advocacy/SafetyIssues/Pages/Summary-of-Bridge-Owner-Responses-to-Safety-Recommendations-H-25-3-and-H-25-04.aspx.

16.

Pavan Acharya, "These Bridges Are at Risk of Disaster. Fixing Many of Them Will Take Years," Politico, February 22, 2026, https://www.politico.com/news/2026/02/22/bridges-from-san-diego-to-philadelphia-are-at-risk-from-ship-collisions-but-efforts-to-protect-them-are-moving-slowly-00780267.

17.

CRS Report R47002, Federal Public Transportation Program: In Brief, by William J. Mallett.

18.

FHWA's Final Rule for National Performance Management Measures: Assessing Pavement Condition for the National Highway Performance Program and Bridge Condition for the National Highway Performance Program became effective on February 17, 2017. See 82 Federal Register 5886, https://www.federalregister.gov/documents/2017/01/18/2017-00550/national-performance-management-measures-assessing-pavement-condition-for-the-national-highway.

19.

The main exception under the core formula programs is that under the Surface Transportation Block Grant Program (STBG), an amount equal to 15% of a state's FY2009 Highway Bridge Program apportionment must be set aside from certain population-based set asides for spending on off-system bridges. Another of the programs, the National Highway Performance Program, requires that, if in the preceding three years more than 10% of the total deck area of bridges in the state on the National Highway System (NHS) is located on bridges classified in poor condition, the state must set aside an amount equal to 50% of the state's FY2009 Highway Bridge Program apportionment for eligible projects on bridges on the NHS. The penalty remains in effect until the NHS deck area on bridges in poor condition is brought below 10% of the total NHS deck area in the state.

20.

Metropolitan Planning Program funds and suballocated funds under the STBG are among those shielded from transfer. See FHWA, "Transferability of Apportioned Program Funding under 23 U.S.C. 126," https://www.fhwa.dot.gov/cfo/23usc126_transferability.cfm.

21.

INFRA awards are administered by the Office of the Secretary of Transportation, not by FHWA.

22.

U.S. Congress, House Committee on Public Works, 1970 National Highway Needs Report, committee print, 91^st Cong., 2^nd sess., February 1970, H.Prt. 91-27 (Washington, DC: GPO, 1970), pp. 30-32. The report estimated that there were 24,000 deficient bridges on the federal-aid system and 64,900 deficient bridges off the federal-aid system.

23.

FHWA, Revised Apportionment of Fiscal Year (FY) 2022 Highway Infrastructure Program Funds for the Bridge Formula Program Pursuant to the Infrastructure Investment and Jobs Act, Notice N 4510.867, April 8, 2022, https://www.fhwa.dot.gov/legsregs/directives/notices/n4510867.cfm.

24.

23 U.S.C. §202(d).

25. FHWA, "Bridge Investment Program," https://www.fhwa.dot.gov/bridge/bip/. 26.

CRS In Focus IF12129, Tribal Highway and Public Transportation Programs, by William J. Mallett.

27.

CRS Report R47724, Emergency Relief Program for Disaster-Damaged Highways and Bridges, by Ali E. Lohman.

28.

CRS Report R48028, Baltimore Bridge Collapse: Frequently Asked Questions (FAQ), by John Frittelli, Ben Goldman, and Ali E. Lohman.

29.

The Consolidated Appropriations Act, 2026 (P.L. 119-75), appropriated $25 million for bridges that are classified by the Bureau of Reclamation as "Type 3" bridges, are owned by a county government, are eligible under the federal lands access program, and cross a water conveyance structure owned by the Bureau of Reclamation.

30.

The "maintain" scenario assumes that capital investment changes so that selected measures of bridge performance in 2038 are maintained at their 2018 levels. The "improve" scenario is the level of spending in which the investment is made in all projects by 2038 for which the economic benefits are equal to or greater than the economic costs.

31. U.S. Department of Transportation, FHWA, and Federal Transit Administration, Status of the Nation's Highways, Bridges, and Transit: Conditions and Performance Report to Congress, 25^th ed., 2024, pp. 2-22, 7-7, https://www.fhwa.dot.gov/policy/25cpr/. 32.

U.S. Department of Transportation, FHWA, and Federal Transit Administration, Status of the Nation's Highways, Bridges, and Transit: Conditions and Performance Report to Congress, 25^th ed., 2024, exhibit 7-11.

33.

The historical estimate of the state and local share of highway capital outlays is taken from Congressional Budget Office, Public Spending on Transportation and Water Infrastructure, 1956 to 2017, supplemental tables 1, 2, and 6, https://www.cbo.gov/publication/54539.

34.

NTSB, "Summary of Bridge Owner Responses to Safety Recommendations H-25-3 and H-25-4."

35.

The balance in the Harbor Maintenance Trust Fund (HMTF) at the end of FY2025 was approximately $10 billion. Department of the Treasury, Bureau of the Fiscal Service, Treasury Bulletin, March 2026, p. 76, https://fiscaldata.treasury.gov/datasets/treasury-bulletin/pdo-1-offerings-of-regular-weekly-treasury-bills.

36.

For more information on the HMTF, see CRS In Focus IF11645, Distribution of Harbor Maintenance Trust Fund Expenditures, by John Frittelli and Nicole T. Carter.

37.

FHWA, Annual Report on Funding Recommendation: Fiscal Year 2024 Bridge Investment Program Large Bridge Projects, June 2024, https://www.fhwa.dot.gov/bridge/bip/fy24_annualreport_funding_largebridgeprojects.pdf.

38.

Sheila Campbell and Chad Shirley, Fiscal Substitution in Spending for Highway Infrastructure, CBO, Working Paper 2021-13, October 2021, pp. 1-45, https://www.cbo.gov/publication/57430. The report notes that their finding is at the lower end of estimates in existing literature.

39.

CRS Report R46343, Transportation Infrastructure Investment as Economic Stimulus: Lessons from the American Recovery and Reinvestment Act of 2009, by William J. Mallett.

40.

For example, the Virginia Department of Transportation (VDOT) and a private partner, Elizabeth River Crossing, offer toll relief from Elizabeth River Tunnels for Hampton Roads residents with annual incomes below $65,000. See VDOT, "VDOT Toll Relief," updated August 4, 2025, https://www.vdot.virginia.gov/travel-traffic/commuters/toll-roads/.

41.

CRS Report R47573, Funding and Financing Highways and Public Transportation Under the Infrastructure Investment and Jobs Act (IIJA), by Robert S. Kirk and William J. Mallett.

42.

The exception to the reconstruction or replacement requirement would be to convert all or some of the bridge lanes to a congestion pricing facility under the Value Pricing Pilot Program.

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