Congress established the Highway Trust Fund in 1956 to hold highway user taxes that fund various surface transportation programs. The primary revenue sources for the Highway Trust Fund are federal excise taxes on motor fuels (gasoline, diesel, and special fuels taxes) and truck-related taxes (truck and trailer sales, truck tire, and heavy-vehicle use taxes). Fuel taxes provide about 89 percent of the excise tax income to the Highway Trust fund. The Highway Trust Fund is divided into two separate accounts—Highway and Mass Transit Accounts. The Highway Account receives the majority (approximately 89 percent in fiscal year 2013) of the tax receipts allocated to the Highway Trust fund, including the majority of the fuel taxes. All truck-related taxes are also deposited into the Highway Account. The Highway Trust Fund primarily supports surface transportation programs administered by four DOT operating administrations—FHWA, FTA, FMCSA, and NHTSA. The Highway Account funds programs administered by FHWA, FMCSA, and NHTSA, and the Mass Transit Account funds FTA programs. For fiscal year 2013, MAP-21 authorized approximately $51 billion from the Highway Trust Fund to four DOT operating administrations, most of which was authorized to FHWA (see fig. 1). These agencies provide much of this funding directly to states, metropolitan-planning organizations, and transit agencies through formula and discretionary grants, and recipients select projects to be funded, subject to federal eligibility requirements. FHWA is primarily funded from the Highway Trust Fund.percent of FHWA’s authorized funds are for the federal-aid highway program. FHWA oversees this program and distributes much of this funding to states through annual apportionments established by statutory formulas. Apportioned funds are available for states to obligate for construction, reconstruction, and improvement of highways and bridges on eligible federal-aid highway routes, as well as for other purposes authorized in law. While FHWA oversees and distributes funds to States, the responsibility for selecting specific highway projects generally rests with state DOTs and local-planning organizations, which have discretion in determining how to allocate available federal funds among various projects. Specifically, FHWA relies on its division offices—52 division offices located in each state, the District of Columbia, and Puerto Rico—to oversee projects funded through the federal-aid highway program and ensure these projects comply with federal requirements. However, FHWA is accountable for ensuring that the federal-aid highway program is delivered effectively, efficiently, and in compliance with established federal law. The remainder of FHWA’s Highway Trust Fund funding (about 10 percent) is authorized for other programs including the Federal Lands Highway Program, which provides financial and engineering assistance for a network of public roads that serve the transportation needs of Federal and Indian Lands and FHWA’s research and education activities. FHWA allocates Highway Trust funds to 28 agencies, such as the Department of Interior. See appendix II for additional information about FHWA’s federal-aid highway and other spending. FTA receives funding from both the Mass Transit Account of the Highway Trust Fund for its Formula and Bus Grants and from the General Fund for its discretionary grants, which include the Capital Investment Grants programs. FTA distributes this funding to grant recipients for several activities, including financial and technical assistance to local and state public agencies to purchase, build, maintain, and operate transportation systems, and to support planning and operations for public transit systems, including bus, subway, and light rail. FTA works in partnership with states and other grant recipients to administer federal transit programs, provide financial assistance, policy direction, technical expertise, and some oversight. State and local governments are ultimately responsible for executing most federal transit programs by matching and distributing federal funds and by planning, selecting, and supervising infrastructure projects and safety programs in accordance with federal requirements. NHTSA receives funding from both the Highway Trust Fund and the General Fund. It administers and distributes Highway Trust Fund monies by formula to states through various federal highway-safety grants, such as the State and Community Highway Safety Grant Program, which is a formula grant. This funding supports programs that work to reduce accidents from speeding, encourage the proper use of seat belts and child seats, reduce accidents from driving while intoxicated, prevent and reduce accidents between motor vehicles and motorcycles, and improve law enforcement services in motor- vehicle accident prevention and traffic supervision, among other things. NHTSA also coordinates through federal-state partnerships, regulates and issues safety standards for passenger vehicles, and addresses compliance issues with safety standards by performing tests, inspections, and investigations. FMCSA receives funding for programs from the Highway Trust Fund. FMCSA is charged with establishing and enforcing standards for motor carrier vehicles and operations, hazardous materials, and the movement of household goods, among other things. FMCSA also conducts compliance reviews of motor carriers’ operations at their places of business as well as roadside inspections of drivers and vehicles, and can assess a variety of penalties, including fines and orders for noncompliant motor carriers to cease interstate operations. The largest of the federal motor carrier safety-grant programs funded from the Highway Trust Fund—the Motor Carrier Safety Assistance Program Grants—provides funding to states to reduce crashes, fatalities, and injuries related to commercial motor vehicle transportation. MAP-21 also authorized Highway Trust Fund funds to be used for agency’s administrative expenses. Currently, FHWA, FMCSA, and NHTSA all receive funding from the Highway Trust Fund for administrative expenses. FTA does not currently receive funding from the Highway Trust Fund for administrative expenses but requested such funding for fiscal year 2015. FHWA collects and reports information on activities funded with obligations from the Highway Trust Fund. FHWA tracks this data for individual projects segments or contracts, but does not collect and report aggregate spending data at the project level for the majority of projects on a routine basis. FTA also collects data on the activities that are funded with Highway Trust Fund obligations each year, while NHTSA and FMCSA collect and report data on obligations from the Highway Trust Fund by grant programs. FHWA, NHTSA, and FMCSA also receive funding from the Highway Trust Fund for administrative expenses. Information on administrative obligations is available in annual budget requests. In fiscal year 2013, FHWA obligated about $41 billion from the Highway Trust Fund, most of which (about $39 billion) was apportioned to states for activities to improve the nation’s roadway and bridge infrastructure through the federal-aid highway program. Our analysis of fiscal year 2013 federal-aid highway program obligations shows that states obligated most of this funding for road and bridge improvements (47 percent for States roads in addition to 17 percent for bridges) (see fig. 2 below).obligated about 20 percent of Highway Trust Fund monies for project development activities including planning, engineering, and acquiring rights-of-way. Additionally, 9 percent was obligated for safety, enhancements and other improvements, including about 1 percent for sidewalks and bicycle trails. We further analyzed road and bridge improvements and found that about 90 percent of obligations went toward reconstruction, resurfacing, and rehabilitation activities, while about 10 percent went toward new construction. Additional information about road and bridge improvements and funding by program are available in appendix II. While FHWA collects information in FMIS on the type of activities funded with Highway Trust Fund monies, it does not currently collect and report aggregate spending data at the project level for the majority of projects on a routine basis.individual project segments or contracts, but not for an entire project. For example, as shown in figure 3, a new highway project generally has four stages: (1) planning, (2) preliminary design and environmental review, (3) final design and right-of-way acquisition and (4) construction. Each stage can include multiple project segments or contracts over many years with distinct obligations at any given time, and FHWA does not currently link all project segments or contracts associated with an entire project in FMIS. Although FHWA is able to collect and report federal obligations by individual contract, it is not able to aggregate this information to collect and report total federal obligations for an entire project. FTA collects and reports information on activities funded with obligations from the Highway Trust Fund. FTA, through its grant management system—the Transportation Electronic Award and Management system, reports information on federal obligations in its annual statistical summaries, and makes this information publicly available on its website. The statistical summaries provide information about federal funds obligated each fiscal year for each of FTA’s grant programs by categories of activities, such as obligations for “bus purchases” or “fixed guideway modernization” (such as rail purchases). FTA obligated approximately $9 billion in fiscal year 2013 from the Mass Transit Account of the Highway Trust Fund through its Formula and Bus Grants programs. These grant programs provided funding for a range of activities, such as to modernize existing rail systems, to increase access to transportation in rural areas, and to restore, replace and acquire buses and other equipment. As shown in table 1, FTA obligated about $3 billion for activities to modernize or improve existing fixed guideway systems, which include among other things, purchases and rehabilitation of rail equipment, and station enhancements. FTA also obligated about $1.5 billion and $2 billion, respectively, for bus purchases and other bus activities in fiscal year 2013. FMCSA collects and reports obligations from the Highway Trust Fund at the grant program level, in its grant management data system, Grant Solutions, and Delphi, DOT’s accounting system. As shown in table 2, FMCSA obligated about $298 million in fiscal year 2013, primarily through grants to states to improve commercial motor carrier vehicle safety, border enforcement, and vehicle license and information systems programs.