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Glossary of Transportation Planning Acronyms and Terms

The transportation arena has a language all its own. Just as getting from point ‘a’ to point ‘b’ in the San Francisco Bay Area is often easier said than done, navigating your way through the complex web of transportation terminology can likewise be a challenge. While MTC strives to use plain language, acronyms and jargon invariably will creep into many discussions about transportation. For this we apologize and offer the following glossary of transportation planning acronyms and terms.


Association of Bay Area Governments
A voluntary association of counties and cities in the nine-county San Francisco Bay Area. ABAG provides demographic, financial, administrative, training and conference services to local governments and businesses. A member sits on MTC.

Article XIX Restriction

A provision in the California Constitution that limits the use of state gasoline tax revenues to projects related to roadway (including bicycle and pedestrian projects) or fixed guideway (rail or trolley coach) improvements.


Bay Area Air Quality Management District
(Also known as the Air District, since the acronym seems to take longer to say than the full name.) Regulates industry and employers to keep air pollution in check and sponsors programs to clean the air. In a joint effort known as the Regional Agency Coordinating Committee (RACC), the Air District works with MTC and the Association of Bay Area Governments on issues that affect transportation, land use and air quality.


Bay Area Toll Authority
BATA, acting as a separate legal entity of MTC, administers the base $1 toll from the Bay Area’s seven state-owned toll bridges (as opposed to the second dollar, a surcharge to cover seismic retrofit costs, which is administered by Caltrans). The state Legislature created BATA in 1998 to take over this responsibility from the California Transportation Commission (CTC).

Bay Area Partnership

Often referred to simply as “The Partnership,” this is a confederation of the top staff of various transportation agencies in the region, including MTC, public transit operators, county congestion management agencies (CMAs), city and county public works departments, ports, Caltrans and the U.S. Department of Transportation (DOT) as well as environmental protection agencies. The Partnership works by consensus to improve the overall efficiency and operation of the Bay Area’s transportation network, including developing strategies for financing transportation improvements.


California Department of Transportation
The state agency that maintains and operates California’s highway system.

Capital Funds

Moneys to cover one-time costs for construction of new projects — such as roads, bridges, bicycle/pedestrian paths, transit lines and transit facilities — to expand the capacity of the transportation system, or to cover the purchase of buses and rail cars.

Census Data

Information used by transportation planners to make projections about future Bay Area travel patterns, housing needs and the like. Required by the U.S. Constitution, the U.S. Census is a complete enumeration of the population conducted every 10 years by the U.S. Census Bureau (the last one was completed in 2000).


Congestion Management Agencies
Countywide agencies responsible for preparing and implementing a county’s Congestion Management Program. CMAs came into existence as a result of state legislation and voter approval of Prop. 111 in 1990. Subsequent legislation made them optional. Most Bay Area counties still have them. Many CMAs double as a county’s sales tax authority.


Congestion Mitigation and Air Quality Improvement Program
A federal source of funding for projects and activities that reduce congestion and improve air quality, both in regions not yet attaining federal air quality standards and those engaged in efforts to preserve their attainment status.

Committed Revenues

Revenues that are dedicated by law, ballot measure or prior MTC programming actions to specific transportation investments. Committed revenues comprise the vast majority of all funds identified in the long-term regional transportation plan. (Also see “Uncommitted Revenues.”)


A process in which transportation plans and spending programs are reviewed to ensure they are consistent with federal clean air requirements; transportation projects collectively must not worsen air quality.


California Transportation Commission
A state-level commission, consisting of nine members appointed by the governor, that establishes priorities and allocates funds for highway, passenger rail and transit investments throughout California. The CTC adopts the State Transportation Improvement Program, or STIP, and implements state transportation policy.

Environmental Justice

This term stems from a Presidential Executive Order to promote equity for disadvantaged communities and promote the inclusion of racial and ethnic populations and low-income communities in decision-making. Local and regional transportation agencies must ensure that services and benefits, as well as burdens, are fairly distributed to avoid discrimination.

Equity Analysis

Consistent with federal requirements for environmental justice, MTC conducts an equity analysis covering the 25-year regional transportation plan to determine how the benefits and burdens of the plan’s investment strategy affect minority and low-income communities.


Federal Highway Administration
U.S. Department of Transportation agency responsible for administering the federal highway aid program to individual states, and helping to plan, develop and coordinate construction of federally funded highway projects. FHWA also governs the safety of hazardous cargo on the nation’s highways.

Financial Constraint

A federal requirement that long-range transportation plans include only projects that have a reasonable expectation of being funded, based upon anticipated revenues. In other words, long-range transportation plans cannot be pie-in-the-sky wish lists of projects. They must reflect realistic assumptions about revenues that will likely be available during the 25 years covered in the plan.

Flexible Funding

Unlike funding that flows only to highways or only to transit by a rigid formula, this is money that can be invested in a range of transportation projects. Examples of flexible funding categories include the Surface Transportation Program (STP) and the Congestion Mitigation and Air Quality Improvement (CMAQ) program.


Federal Transit Administration
U.S. Department of Transportation agency that provides financial and planning assistance to help plan, build and operate rail, bus and paratransit systems. The agency also assists in the development of local and regional traffic reduction programs.


Fiscal Year
Annual schedule for keeping financial records and for budgeting transportation funds. California’s fiscal year runs from July 1 through June 30, while the federal fiscal year runs from Oct. 1 through Sept. 30.


Housing Incentive Program
A program initiated by MTC to provide seed money to municipalities and their development partners to encourage the development of compact residential communities near public transit hubs.

HOV Lane

High-Occupancy-Vehicle Lane
The technical term for a carpool lane, commuter lane or diamond lane.


The term “mode” is used to refer to a means of transportation, such as automobile, bus, train, ship, bicycle and walking. Intermodal refers specifically to the connections between modes.

Lifeline Transportation Network

An MTC initiative to enhance low-income residents’ access to key destinations such as job centers, government buildings and medical facilities during both peak commute periods and off-peak hours. While most of the Lifeline network identified by MTC is already served by existing transit routes, some low-income communities and/or destinations are not served by transit or lack service at specific times of day. MTC is working with transit operators and potential funding partners to fill these gaps in the network.


Low-Income Flexible Transportation
An MTC program that provides financial assistance for services to help low-income residents get to and from work and other locations. Examples of eligible LIFT projects include new and expanded public transit services, transportation to child care centers, development of child care facilities at transit hubs, rideshare activities and “guaranteed ride home” programs.


Metropolitan Planning Organization
A federally required planning body responsible for the transportation planning and project selection in its region; the governor designates an MPO in every urbanized area with a population of over 50,000. MTC is the Bay Area’s MPO.


Metropolitan Transportation Commission
The transportation planning, financing and coordinating agency for the nine counties of the San Francisco Bay Area.


Metropolitan Transportation System
A defined network of streets and roads, highways, mass transit routes, bikeways, transfer points, airports and seaports considered essential to regional mobility.

Ozone Attainment Strategy

This plan details the strategy by which the Bay Area will comply with federal ozone — or “smog” — standards. The Ozone Attainment Strategy is prepared by the Bay Area Air Quality Management District, the Association of Bay Area Governments and MTC, then submitted for review and approval by the California Air Resources Board and the U.S. Environmental Protection Agency. The plan also provides a transportation “emissions budget” that identifies allowable levels of pollution from motor vehicles traveling in the Bay Area. (Also see “Conformity.”)


Door-to-door bus, van and taxi services used to transport elderly and disabled riders. Sometimes referred to as dial-a-ride service, since trips are made according to demand instead of along a fixed route or according to a fixed schedule.

Performance Measures

Indicators of how well the transportation system or specific transportation projects will improve transportation conditions.

Potential New Revenues

Funds that may be available for transportation investment in the future if proposed new revenue sources are approved. Current legislative proposals include a $1 increase in the base toll on state-owned bridges and indexing the federal gasoline tax to inflation. These potential revenues are not included in the financially constrained portion of the long-term transportation plan.


(1) verb, to assign funds to a project that has been approved by MTC, the state or another agency and (2) noun, a system of funding for implementing transportation projects or policies, such as through the State Transportation Improvement Program. (Also see “STIP.”)

Proposition 42

A state constitutional amendment passed by California voters in March 2002 that permanently dedicates 100 percent of the state sales tax on gasoline for transportation investments, although the Legislature is able to suspend these provisions in times of fiscal crisis.


Regional Agency Coordinating Committee
A nine-member committee — composed of three representatives each from MTC, the Bay Area Air Quality Management District and the Association of Bay Area Governments — that coordinates activities of the three agencies on issues that affect transportation, land use and air quality.


Regional Transit Expansion Program
An identified list of high-priority rail and express/rapid bus improvements to serve the Bay Area’s most congested corridors. The program was adopted in December 2001 pursuant to MTC Resolution 3434 to establish clear priorities for the investment of transit expansion funds over the next decade.

Resolution 3434

See Regional Transit Expansion Program.

Return to Source

A requirement with some funding programs (such as TDA) that the money flow back to the county where it originated from tax revenues, regardless of need.


Regional Transportation Improvement Program
A listing of highway, local road, transit and bicycle projects that the region hopes to fund; compiled by MTC every two years from priority lists submitted by local jurisdictions. The California Transportation Commission (CTC) must either approve or reject the RTIP in its entirety. Once the CTC approves an RTIP, it is combined with those from other regions to comprise 75 percent of the funds in the State Transportation Improvement Program or STIP. (Also see “STIP.”)


Regional Transportation Plan
A master plan to guide the region’s transportation investments for a 25-year period. Updated every three years, it is based on projections of growth in population and jobs and the ensuing travel demand. Required by state and federal law, it includes programs to better maintain, operate and expand transportation. The Bay Area’s 2005 update of its long-range transportation plan, now under way, is known as Transportation 2030.


Service Authority for Freeways and Expressways
As the region’s SAFE, MTC, in partnership with the California Highway Patrol and the California Department of Transportation, oversees the installation and operation of call boxes along Bay Area freeways and highways, and administers a roving tow truck service to quickly clear incidents from the region’s most congested roadways. State legislation in 1987 created the MTC SAFE, which is funded in part through a $1 surcharge on motor vehicle registrations.

Sales Tax Authority

An agency that administers a voter-approved county transportation sales tax program; in most Bay Area counties, the congestion management agency (CMA) also serves as the sales tax authority.

Self-Help Counties

A term used to describe counties that have taken the initiative to supplement available state and federal funds by enacting local voter-approved funding mechanisms — such as half-cent sales taxes — to pay for transportation improvements. In the Bay Area, five counties have passed such measures: Alameda, Contra Costa, San Francisco, San Mateo and Santa Clara.

Smart Growth

A set of policies and programs designed to protect, preserve and economically stimulate established communities, while protecting valuable natural and cultural resources and limiting sprawl.


Single-Occupant Vehicle
A vehicle with one occupant, the driver, who is sometimes referred to as a “drive alone.”


State Transit Assistance
Provides funding for mass transit operations and capital projects.


State Transportation Improvement Program
What the California Transportation Commission (CTC) ends up with after combining various RTIPs, as well as a list of specific projects proposed by Caltrans. Covering a five-year span and updated every two years, the STIP determines when and if transportation projects will be funded by the state. Projects included in the STIP must be consistent with the long-range transportation plan.


Surface Transportation Program
One of the key funding programs in TEA 21. STP moneys are “flexible,” meaning they can be spent on mass transit, pedestrian and bicycle facilities, as well as on roads and highways.

System Management

A coordinated series of programs involving MTC and partner agencies such as the California Highway Patrol and Caltrans to make the region’s existing transportation system work more efficiently. These efforts include congestion relief initiatives such as the roving Freeway Service Patrol tow trucks, and traveler information programs such as the toll-free 511 phone service and the Web page.


Transportation Control Measure
A strategy to reduce driving or smooth traffic flows in order to cut auto emissions and resulting air pollution. Required by the Clean Air Act, TCMs for the Bay Area are developed by MTC. Examples of TCMs include carpool lanes, roving tow truck patrols to clear stalls and accidents from congested roadways, new or increased transit service, and ridesharing services to get people into carpools and vanpools.


Traffic Congestion Relief Program
A five-year state transportation investment plan passed by the California Legislature and signed into law by Governor Gray Davis in 2000. The plan originally called for $6.8 billion of spending (with $1.7 billion to the Bay Area) from fiscal 2000–01 to 2005–06, but subsequent refinancing agreements postponed the funding until fiscal 2002–03 to 2007–08.


Transportation Development Act
State law enacted in 1971. TDA funds are generated from a tax of one-quarter of one percent on all retail sales in each county; used for transit, special transit for disabled persons, and bicycle and pedestrian purposes. TDA moneys are collected by the state and allocated in the Bay Area by MTC to fund transit operations and programs. In non-urban areas, TDA funds may be used for streets and roads under certain conditions.


Transportation Enhancement Activities
A TEA 21 funding category. Ten percent of STP moneys must be set aside for projects that enhance the compatibility of transportation facilities with their surroundings. Examples of TEA projects include bicycle and pedestrian paths, restoration of rail depots or other historic transportation facilities, acquisition of scenic or open space lands next to travel corridors, and murals or other public art projects.

TEA 21

Transportation Equity Act for the 21st Century
Passed by Congress in May 1998, this federal transportation legislation retains and expands many of the programs created in 1991 under the Intermodal Surface Transportation Efficiency Act (ISTEA). Reauthorizes federal surface transportation programs for six years (1998–2003) and significantly increases overall funding for transportation.

Title VI

Refers to Title VI of the Federal Civil Rights Act of 1964, and requires that transportation planning and programming be nondiscriminatory on the basis of race, color and national origin. Integral to Title VI is the concept of environmental justice. (Also see “Environmental Justice.”)


Transportation Improvement Program
A short-term (covering three years) program of transportation projects that will be funded with all federal funds expected to flow to the region; the projects contained in the TIP are drawn from, and consistent with, the long-range transportation plan.


Transportation for Livable Communities
Program created by MTC in 1998 to fund small-scale, community- and transit-oriented projects that improve neighborhood vitality.


Transit-Oriented Development
A type of development that links land use and transit facilities to support the transit system and help reduce sprawl, traffic congestion and air pollution. It includes housing, along with complementary public uses (jobs, retail and services), located at a strategic point along a regional transit system, such as a rail hub.

Transportation 2030 Plan

The long-range transportation planning effort now under way in the nine-county Bay Area to guide transportation policy and investment decisions through the year 2030.

Travel Demand Model

Used by transportation planners for simulating current travel conditions and for forecasting future travel patterns and conditions. Models help planners and policy-makers analyze the effectiveness and efficiency of alternative transportation investments in terms of mobility, accessibility, and environmental and equity impacts.

Tribal Government Consultation

A formal process between MPOs and federally recognized Indian tribes, which are recognized as sovereign nations, that calls for government-to-government consultation regarding transportation planning and programming efforts.

Uncommitted Revenues

Anticipated transportation revenues available for new investments after accounting for revenue committed by law, ballot measure or MTC programming actions. These revenues account for about 10 percent of all revenues forecasted to be available over the 25-year period of the regional transportation plan, and are the major focus of the update process. (Also see “Committed Revenues.”)


United States Department of Transportation
The federal cabinet-level agency with responsibility for highways, mass transit, aviation and ports; it is headed by the Secretary of Transportation. The DOT includes the Federal Highway Administration and the Federal Transit Administration, among others. There also are state DOTs (known in California as Caltrans).

Value Pricing

The concept of assessing higher prices for using certain transportation facilities during the most congested times of the day, in the same way that airlines offer off-peak discounts and hotel rooms cost more during prime tourist seasons. Also known as congestion pricing and peak-period pricing, examples of this concept include higher bridge tolls during peak periods or charging single-occupant vehicles that want to use carpool lanes.


Vehicle Miles Traveled

One vehicle (whether a car carrying one passenger or a bus carrying 30 people) traveling one mile constitutes a vehicle mile. VMT is one measure of the use of Bay Area freeways and roads.