Highlights

This edition of the C&P Report is based primarily on data through 2014. In assessing recent trends, this report generally focuses on the 10-year period from 2004 to 2014. The prospective analyses generally cover the 20 year period ending in 2034; the investment levels associated with these scenarios are stated in constant 2014 dollars. This section presents key findings for the overall report; key findings for individual chapters are presented in the Executive Summary.

Highlights: Highways and Bridges

Extent of the System

Highway System Terminology

“Federal-aid highways” are roads that generally are eligible for Federal funding assistance under current law. (Note that certain Federal programs do allow the use of Federal funds on other roadways.)

The “National Highway System” (NHS) includes those roads that are most important to interstate travel, economic expansion, and national defense. It includes the entire Interstate System. The NHS was expanded under MAP-21.

Spending on the System

Extent of the highway system

Constant-Dollar Conversions for Highway Expenditures

This report uses the Federal Highway Administration’s National Highway Construction Cost Index (NHCCI) 2.0 for inflation adjustments to highway capital expenditures and the Consumer Price Index (CPI) for adjustments to other types of highway expenditures. From 2004 to 2014 the NHCCI 2.0 increased by 51.5 percent (4.2 percent per year), while the CPI increased by only 25.3 percent (2.3 percent per year). Previous editions of the C&P Report reflected an earlier version of the NHCCI, which showed smaller increases than the CPI in recent years.

Highway Capital Spending Terminology


This report splits highway capital spending into three broad categories. “System rehabilitation” includes resurfacing, rehabilitation, or reconstruction of existing highway lanes and bridges. “System expansion” includes the construction of new highways and bridges and the addition of lanes to existing highways. “System enhancement” includes safety enhancements, traffic control facilities, and environmental enhancements.


Conditions and Performance of the System

Highway vehicle miles traveled increased by 2.0 percent (0.2 percent per year) from 2004 to 2014, while highway capital spending declined by 1.0 percent in constant-dollar terms (and overall highway spending increased). These trends were present while indicators of the performance and condition of the overall system had mixed results.

Pavement Condition Trends Have Been Mixed

Pavement Condition Terminology

This report uses the International Roughness Index (IRI) as a proxy for overall pavement condition. Pavements with an IRI value of less than 95 inches per mile are considered to have “good” ride quality. Pavements with an IRI value greater than 170 inches per mile are considered to have “poor” ride quality. Pavements that fall between these two ranges are considered “fair.”

FHWA Bridge Classifications

FHWA is currently transitioning to a new set of bridge condition descriptors. Bridges are given an overall rating of “poor” if the deck, substructure, or superstructure is found to be in poor condition due to deterioration or damage. The legacy term “structurally deficient” includes “poor” bridges as well as those failing other criteria, such as adequacy of the waterway opening under the bridge. The classification of a bridge as poor or structurally deficient does not mean it is unsafe.

These classifications are often weighted by bridge deck area, recognizing that bridges are not all the same size and, in general, larger bridges are more costly to rehabilitate or replace to address deficiencies. The classifications are also sometimes weighted by annual daily traffic, recognizing that more heavily traveled bridges have a greater impact on total highway user costs.

Another legacy term is “functionally obsolete,” which relates to the geometric characteristics of a bridge (e.g., bridge width, load-carrying capacity, clearances, approach roadway alignment) in relation to current design standards. The magnitude of such deficiencies determines whether a bridge is classified as “functionally obsolete.” This metric is a legacy classification that was used to implement the Highway Bridge Program, which was discontinued as a separate program with the enactment of MAP-21. In the absence of a programmatic reason to collect the data necessary to support this classification, some of the data necessary to compute it are being removed from the National Bridge Inventory. Future editions of the C&P Report will not contain this information. This edition presents “functionally obsolete” as a measure of operational performance, rather than a measure of physical conditions.


Bridge Condition Trends Have
Been Mixed

  • Based directly on bridge counts, the share of bridges classified as poor has improved, dropping from 11.0 percent in 2004 to 8.7 percent in 2014 (and to 8.3 percent in 2015). The share of NHS bridges classified as poor also improved over this period, dropping from 5.6 percent to 4.1 percent (and to 3.7 percent in 2015).
  • Weighted by deck area, the share of bridges classified as poor improved, declining from 9.4 percent in 2004 to 6.7 percent in 2014 (and to 6.4 percent in 2015). The deck area-weighted share of poor NHS bridges dropped from 8.7 percent to 5.8 percent over this period (and to 5.5 percent in 2015).
  • Weighted by deck area, the share of bridges classified as structurally deficient improved, declining from 10.1 percent in 2004 to 7.1 percent in 2014. The deck area-weighted share of structurally deficient NHS bridges dropped from 8.9 percent to 6.0 percent over this period.
  • While the percentage of poor bridges has declined over the last decade, the share of bridges classified as good has also gone down. Weighted by deck area, the share of bridges classified as good worsened, declining from 46.1 percent in 2004 to 44.7 percent in 2014 (before rebounding to 45.5 percent in 2015). The deck area-weighted share of good NHS bridges dropped from 43.8 percent to 42.2 percent over this period (rising to 43.0 percent in 2015).

Operational Performance in Urbanized Areas Has Slowly Worsened

  • The Texas Transportation Institute 2015 Urban Mobility Scorecard estimates that the average commuter in 471 urbanized areas experienced a total of 42 hours of delay resulting from congestion in 2014, up from 41 hours in 2004. Congestion delay was worse in the largest metro areas, for example averaging 82 hours in Washington D.C., 80 hours in Los Angeles/Long Beach, 78 hours in San Francisco/Oakland, and 74 hours in New York/Newark. Total delay experienced by all urbanized area travelers combined rose by 11.5 percent from 6.1 billion hours in 2004 to 6.8 billion hours in 2014, an all-time high.
  • The combined cost of wasted time and wasted fuel caused by congestion in urbanized areas rose from an estimated $136 billion in 2004 to $160 billion in 2014. Although these costs had declined during the most recent recession, they now exceed their pre-recession peak.
  • One indicator with more positive trends relates to bridge geometrics, which can influence operational performance. Based directly on bridge counts, the share of bridges classified as functionally obsolete declined from 15.2 percent in 2004 to 13.8 percent in 2014 (unchanged at 13.8 percent in 2015). Weighted by deck area, the share of bridges classified as functionally obsolete improved slightly, dropping from 20.5 percent in 2004 to 20.3 percent in 2014 (before rebounding to 20.5 percent in 2015). Functional obsolescence tends to be a more significant problem on larger bridges carrying more traffic.
Highway system trends

Highway Safety Improved Overall, but Nonmotorist Fatalities Rose

Future Capital Investment Scenarios

The scenarios that follow pertain to spending by all levels of government combined for the 20-year period from 2014 to 2034 (reflecting the impacts of spending from 2015 through 2034); the funding levels associated with all of these analyses are stated in constant 2014 dollars. The results below apply to the overall road system; separate analyses for the Interstate System, the NHS, and Federal-aid highways are presented in the body of this report.

Modeled vs. Nonmodeled Investment


Each highway investment scenario includes projections for system conditions and performance based on simulations using the Highway Economic Requirements System (HERS) and National Bridge Investment Analysis System (NBIAS). Each scenario scales up the total amount of simulated investment to account for capital improvements that are outside the scopes of the models, or for which no data are available to analyze. In 2014, 13.5 percent of highway capital spending was used for system enhancements (safety enhancements, traffic control facilities, and environmental enhancements) that neither model analyzes directly. An additional 15.8 percent was used in 2014 for pavement and capacity improvements on non-Federal-aid highways; FHWA does not collect the detailed information for such roadways that would be necessary to support analysis using HERS. (FHWA does collect sufficient data for all of the nation’s bridges to support analysis using NBIAS.)

Combining these two percentages yields a total of 29.3 percent; each scenario for the overall road system was scaled up so that nonmodeled investment would comprise this share of its total investment level.

Highway Investment / Performance Analyses


To provide an estimate of the costs that might be required to maintain or improve system performance, this report includes a series of investment/performance analyses that examine the potential impacts of alternative levels of future combined investment by all levels of government on highways and bridges for different subsets of the overall system

Drawing on these investment/performance analyses, a series of illustrative scenarios was selected for more detailed exploration and presentation.

The Sustain 2014 Spending scenario and the Maintain Conditions and Performance scenario each assume a fixed level of highway capital spending in each year in constant-dollar terms (i.e., spending keeps pace with inflation each year).

Spending under the Improve Conditions and Performance scenario varies by year depending on the set of potential cost-beneficial investments available at that time. Because there is an existing backlog of cost-beneficial investments that have not previously been addressed, investment under this scenario is frontloaded, with higher levels of investment in the early years of the analysis and lower levels in the latter years.

Sustain 2014 Spending Scenario

Maintain Conditions and Performance Scenario

Highway system trends

Improve Conditions and Performance Scenario

Highlights: Transit

Extent of the System

Bus, Rail, and Demand Response: Transit Modes


Public transportation is provided by several different types of vehicles that are used in different operational modes. The most common is fixed-route bus service, which uses different sizes of rubber-tired buses that run on scheduled routes. Commuter bus service is similar, but uses over-the-road buses and runs longer distances between stops. Bus rapid transit is high-frequency bus service that emulates light rail service. Públicos and jitneys are small owner-operated buses or vans that operate on less-formal schedules along regular routes.

Larger urban areas are often served by one or more varieties of fixed-guideway (rail) service. These include heavy rail (often running in subway tunnels), which is primarily characterized by third-rail electric power and exclusive dedicated guideway. Extended urban areas may have commuter rail, which often shares track with freight trains and often uses overhead electric power (but may also use diesel power or third rail). Light rail systems are common in large-and medium-sized urban areas; they feature overhead electric power and run on track that is entirely or in part on city streets that are shared with pedestrian and automobile traffic. Streetcars are small light rail systems, usually with only one or two cars per train that often run in mixed traffic. Hybrid Rail, previously reported as light rail or commuter rail, is a mode with shared characteristics of these two modes. It has higher average station density (stations per track mileage) than commuter rail and lower than light rail; it has a smaller peak-to-base ratio than that of commuter rail. Cable cars, trolley buses, monorail, and automated guideway systems are less-common fixed-guideway systems.

Demand-response transit service is usually provided by vans, taxicabs, or small buses that are dispatched to pick up passengers upon request. This mode is mostly used to provide paratransit service as required by the Americans with Disabilities Act. These vehicles do not follow a fixed schedule or route.

2004-2014 Transit Trends. This exhibit illustrates transit trends in urban areas from 2004 to 2014. All levels of government spent a combined $65.1 billion in 2014 to provide public transportation and maintain transit infrastructure, with $47.6 billion spent for the operating expenses. Of this, 35.5 percent was system-generated revenue, 8.6 percent was federal funding, 25.4 percent was state sources, and 30.4 percent was local sources. Public transit agencies spent $17.5 billion on capital investments in 2014. Federal funding (including Recovery Funds) of capital investments comprised 42.0 percent of total 2014 spending, while 13.7 percent was state sources and 44.6 percent was local sources. Total annual route miles increased 11.4 percent from 225,383 in 2004 to 251,121 in 2014. Average annual route miles traveled by bus increased by 10.6 percent, average annual route miles traveled by heavy rail increased by 2.0 percent, average annual route miles traveled by commuter rail increased by 27.2 percent, and average annual route miles traveled by light rail increased by 113.1 percent. The annual number of transit fatalities, including suicide and commuter rail fatalities, increased by 30.0 percent from 2004 to 2014, rising from 247 fatalities to 321 fatalities. Average operating cost per vehicle mile for the top 10 agencies increased by 23.2 percent from 2004 to 2014, rising from $12.9 to $15.9 in constant dollars; nationwide, the average operating cost per vehicle mile increased by 9.7 percent (from $9.2 to $10.1 in constant dollars) from 2004 to 2014. Average recovery ratios for the top 10 agencies decreased by 3.5 percent, from a 33.9 average recovery ratio in 2004 to a 32.7 average recovery ratio in 2014; nationwide average recovery ratios for the top 10 agencies increased 2.6 percent, from a 35.2 average recovery ratio in 2004 to a 36.1 recovery ratio in 2014.

Federal Transit Funding Urban and Rural

Federal Transit Administration (FTA) Urbanized Area Formula Funds are apportioned to urbanized areas (UZAs), as defined by the Census Bureau. UZAs in this report were defined by the 2010 census. Each UZA has a designated recipient, usually a metropolitan planning organization (MPO) or large transit agency, which then sub-allocates FTA funds in its area according to local policy. The designated recipient may then allow these organizations to apply directly for a grant with FTA as a designated recipient. In small urban and rural areas, FTA apportions funds to the State, which allocates them according to State policy. Indian tribes are apportioned their formula funds directly. Once obligated in a grant, all funds then become available, on a reimbursement basis.

Spending on the System

Conditions and Performance of the System


Some Aspects of System Performance Have Improved

Fatalities Increased Due to an Increase in Suicides

Transit Trends 2004-2014

Unlinked Passenger Trips, Passenger Miles, Route Miles, and Revenue Miles


Unlinked passenger trips (UPT), also called boardings, count every time a person gets on an in-service transit vehicle. Each transfer to a new vehicle or route is considered another unlinked trip, so a person’s commute to work may count as more than one trip if that person transferred between routes.

Passenger miles traveled (PMT) simply count how many miles people travel on transit. UPT and PMT are both commonly used measures of transit service consumed.

Directional route miles (DRM) measure the number of miles of transit route available to customers. They are directional because each direction counts separately; thus, a one-mile-out and one-mile-back bus route would be two DRM. Vehicle Revenue Miles (VRM) count the miles of revenue service provided by transit operators over their networks.

Future Capital Investment Scenarios–Systemwide

As in the highway discussion, the transit investment scenarios that follow pertain to spending by all levels of government combined for the 20-year period from 2014 to 2034 (reflecting the impacts of spending from 2015 through 2035); the funding levels associated with all of these analyses are stated in constant 2014 dollars. These transit scenarios also assume an immediate jump to a higher (or lower) investment level that is maintained in constant-dollar terms throughout the analysis period.

Included in this section for comparison purposes is an assessment of the investment level needed to replace all assets that are currently past their useful life or that will reach that state over the forecast period. This level of investment would be necessary to achieve and maintain a state of good repair (SGR), but would not address any increases in demand during that period. Although not a realistic scenario, it provides a benchmark for infrastructure preservation investment requirements. All capital investment scenarios are subjected to cost-benefit constraints.

State of Good Repair – Expansion vs. Preservation


State of Good Repair (SGR) is defined in this report as all transit capital assets being within their useful service life. This is a general construct that allows FTA to estimate system preservation needs. The analysis looks at the age of all transit assets and adds the value of those that are past the age at which that type of asset is usually replaced to a total reinvestment needs estimate. Some assets may continue to provide reliable service well past the average replacement age and others will not; over the large number of assets nationally, the differences are assumed to average out. Some assets will need to be replaced, some will just get refurbished

Expansion needs are treated separately in this analysis. They result from the need to add vehicles and route miles to accommodate more riders. Failure to meet this type of need results in crowded vehicles and represents a lost opportunity to provide the benefits of transit to a wider customer base.

Future Transit Capital Investment Scenarios

Sustain 2014 Spending Scenario

Low-Growth Scenario

High-Growth Scenario

Report Submitted to Congress on November 22, 2019.
Page posted on October 22, 2020