Glossary
Transportation Terms and Acronyms
Access, limited (or controlled access) – In transportation, to have entry and exit limited to predetermined points, as with interstates, freeways and rapid transit.
Arterial street – A major thoroughfare used primarily for through traffic rather than for access to abutting land, characterized by high vehicular capacity and continuity of movement.
Average Daily Traffic (ADT) – The average number of vehicles that pass a specified point during a 24 hour period.
Base Year – The year to which the major portion of the data gathered in a (transportation) study or survey relates. The base year is also the first year of a planning or forecast period.
Benefit cost analysis – An analytical technique that compares the costs and benefits (measured in monetary terms) of proposed programs or policy actions. Alternative actions are compared to allow selection of one or more that yields the greatest net benefit or benefit cost ratio.
Benefit cost ratio – The ratio of the dollars of benefits achievable to the given outlay of costs.
Bus Rapid Transit (BRT) – Buses operating primarily on their own dedicated lane or right-of-way.
Clean Air Act (CAA) – The Clean Air Act is the law that defines EPA's responsibilities for protecting and improving the nation's air quality and the stratospheric ozone layer. The Clean Air Act was enacted by Congress in 1990. Legislation passed since then has made several minor changes. In nonattainment and maintenance areas, federal funding and approval for transportation projects is only available if transportation activities are consistent with air quality goals through the transportation conformity process. The transportation conformity process includes a number of requirements that MPOs must meet.
Capital costs – Nonrecurring or infrequently recurring costs of long term assets such as land, structures, bridges, roadways, and vehicles (such as publicly owned and operated transit vehicles).
CART – Cleveland Area Rapid Transit; the transit operator of the Norman Bus System.
Citizens Advisory Committee (CAC) – An ACOG committee tasked with providing critical public input and expertise to help shape future transportation activities.
Commuter Rail Transit (CRT) – Passenger trains operated on or adjacent to a main line railroad track to carry riders to and from work in city centers.
Constant dollars – Current dollars, that is, the value of the dollar for the year selected as a base, adjusted by using the change in the GNP deflator index or other specified indicator between the current (base) year and the desired year. The intent of using constant dollars is to remove the distortion caused by inflation during the intervening time period.
Corridor – In planning, a broad geographical band that follows a general directional flow or connects major sources of trips. It may contain a number of streets and highways.
Council of Governments (COG) – A voluntary consortium of local government representatives, from contiguous communities, meeting on a regular basis and formed to cooperate on common planning and to solve common development problems of their area. In Central Oklahoma, the Association of Central Oklahoma Governments (ACOG) serves as the COG representing the communities within Oklahoma, Cleveland, Canadian, and Logan Counties.
COTPA – Central Oklahoma Transportation and Parking Authority; the transit operator of the Oklahoma City bus system.
Cutline – In planning, an imaginary line drawn perpendicular to the flow of traffic to measure congestion in a subarea. Cutlines are generally drawn across major traffic corridors.
Department of Transportation (DOT) – A municipal, county, state, or federal agency responsible for transportation. On the federal level, the U.S. DOT is a cabinet level federal agency responsible for the planning, safety, and system and technology development of national transportation, including highways, mass transit, aircraft, and ports. On the state level, the Oklahoma Department of Transportation (ODOT) oversees planning, design and construction of transportation improvements statewide under the direction of the Secretary/Director of Transportation.
Endangered or Threatened Species – Animal and plant species which have been identified for special protection under the Endangered Species Act of 1973.
Environmental Justice – A 1994 Presidential Executive Order implemented by the United States Department of Transportation that requires agencies receiving federal transportation dollars to identify and address, as appropriate, disproportionately high and adverse human health or environmental effects of their programs, policies, and activities on minority populations and low-income populations
Environmental Protection Agency (EPA) – An independent federal agency in the executive branch whose responsibilities include development and enforcement of national air quality emission standards and support of anti pollution activities by state and local governments.
Federal Highway Administration (FHWA) – A component of the U.S. Department of Transportation, established to ensure development of an effective national road and highway transportation system. It assists states and local governments in constructing highways and roads.
Federal Transit Administration (FTA) – A component of the U.S. Department of Transportation, delegated by the Secretary of Transportation to administer the federal transit program under the Urban Mass Transportation Act of 1964, as amended, and various other statutes.
Financial Constraint (or Fiscally Constrained) – Financial information in Metropolitan transportation plan and TIP that demonstrates that projects can be implemented using committed available, or reasonably available revenue sources, while adequately continuing to operate and maintain the transportation system.
Forecasting – In planning, the process of determining the future conditions, magnitudes, and patterns within the urban area, such as future population, demographic characteristics and travel demand.
Forecast (or target) year – In planning, the terminal year for a projection. Usually designates the year in the future for which the improvements embraced in the transportation plan are to be designed.
Freeway – A divided highway for through traffic that has full access control and grade separations at all intersections.
Goal – A broad statement of direction in which planning or action is aimed; a general value statement representing an ideal end that the community or area wishes to attain.
Grade separated crossing – A crossing where the intersecting facilities (road, rail, etc.) are separated vertically.
HOV Lane – A high occupancy vehicle lane. A lane of traffic that is delineated for use by transit buses or passenger vehicles carrying more than one occupant.
Home-based trip – A trip that has either its origin or destination at the traveler's residence.
Input – Information to be used in an analysis.
Intelligent Transportation System (ITS) – The application of advanced technology to current transportation problems, including incident detection, signal coordination, real-time information, and other technology.
Intermodal – The interaction of various modes of transportation, particularly as it relates to connections, choices, coordination and cooperation.
Intermodal Transportation Policy Committee (ITPC) – An OCARTS area committee composed of an elected official from each member entity and representatives of local, state, and federal transportation agencies. This committee is responsible for transportation policies, plan review and adoption, and development of programs for plan implementation.
Intermodal Transportation Technical Committee (ITTC) – An advisory committee to the ITPC composed of technical representatives from each OCARTS entity and representatives of transportation agencies, including staff persons knowledgeable in engineering, planning, and administration. Transportation policies, plans and programs are presented to the ITTC for a recommendation prior to consideration by the ITPC.
Intersections – Are classified into three general categories: grade- separated without ramps, grade- separated with ramps (commonly known as interchanges), and at- grade intersection. The main function of intersection is to provide for the change of route directions.
ISTEA – Intermodal Surface Transportation Efficiency Act. The Act was signed into law on December 18, 1991, and was effective for a six-year period (federal fiscal years 1992 through 1997). ISTEA resulted in broad changes to the way transportation decisions are made by emphasizing diversity and balance of modes and preservation of existing systems over construction of new transportation facilities. Plans must consider social, environmental, and energy factors in planning, programming and project selection. ISTEA was replaced by TEA-21.
Land Use – The purpose for which land or the structure on the land is being used; for example, residential, commercial, light industry, etc.
Level of Service (LOS) – A set of characteristics that indicate the quality and quantity of transportation service provided. For highway systems, a qualitative rating of the effectiveness of a highway or highway facility in serving traffic in terms of operating conditions. The Highway Capacity Manual identifies operating conditions ranging from A, for best operation (low volume, high speed), to F, for worst conditions.
Link – A section of a transportation system network defined by intersection points (nodes) at each end. A link connects two nodes, and may be one- way or two- way.
Metropolitan Statistical Area (MSA) – As designated by the U.S. Office of Management and Budget and defined by the U.S. Bureau of the Census, an MSA consists of the central county or counties containing a city or an urbanized area with a population of at least 50,000 and the adjacent or outlying counties that have close economic and social relationships with the central counties, with a total metropolitan population of at least 100,000. The term was adopted after the 1980 census and replaces the term Standard Metropolitan Statistical Area (SMSA).
Metropolitan Planning Organization (MPO) – According to the United States Code, the organization designated by the governor and local elected officials as responsible, together with the state, for transportation planning in an urbanized area. It serves as the forum for cooperative decision making by principal elected officials of general local government. In Central Oklahoma, ACOG serves as the MPO.
Metropolitan Transportation Plan – The official intermodal transportation plan developed and adopted through the Metropolitan Planning Organization's (MPO) transportation planning process; also known as the long-range plan (LRP).
Mode – A means of transporting people and goods, which includes automobiles, transit (i.e. buses, carpooling, HOV lanes, fixed guideway), bicycling, walking, air travel, railroads, waterways, and trucking.
Multimodal – Refers to all types of transportation.
Network, OCARTS – In highway engineering, the configuration of major streets and highways that constitutes the regional system.
Non home based trip – A trip that has neither its origin nor its destination at a residence.
OCARTS – Oklahoma City Area Regional Transportation Study; OCARTS refers to a geographical area within Central Oklahoma (for transportation planning) which includes all of the currently urbanized area plus the surrounding area which is anticipated to become urbanized over the next 20 years. The OCARTS area encompasses all of Oklahoma County, and Cleveland Counties with portions of Canadian, Cleveland, Grady, Logan and McClain Counties.
Oklahoma Employment Security Commission (OESC) – An agency of the State of Oklahoma responsible for collecting and analyzing various population and employment statistics. The OESC also provides data to the U.S. Department of Labor for federal government level statistical analysis.
Output – Something produced, such as the result of an analytical process.
Parameter – A measurable, fixed characteristic of a sample or population. Also an independent variable used in the development of mathematical models.
Park and Ride – A regional or municipal system that provides parking for suburban commuters at outlying stations of a bus or rail line.
Regional Transit Dialogue (RTD) – Vision or guide for OKC metro area’s future multi-modal
transit opportunities, expand transportation options, and enhance economic development opportunities.
Right of way (ROW) – A general term denoting land, property, or interest therein, usually in a strip acquired for or devoted to transportation purposes.
SAFETAE-LU: Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users – Signed into law on August 10, 2005, SAFETA- LU guarantees funding for highways, highway safety, and public transportation totaling $244.1 billion. SAFETEA-LU represents the largest surface transportation investment in our Nation's history. The two landmark bills that brought surface transportation into the 21st century—the Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA) and the Transportation Equity Act for the 21st Century (TEA-21)—shaped the highway program to meet the Nation's changing transportation needs. SAFETEA-LU builds on this firm foundation, supplying the funds and refining the programmatic framework for investments needed to maintain and grow our vital transportation infrastructure.
Statewide Transportation Improvement program (STIP) – The STIP is similar to the TIP in that it identifies statewide priorities for transportation projects and must be fiscally constrained.
State Planning and Research Program (SPR) – Similar to the UPWP in that it lists the transportation studies, research and tasks to be performed by the state DOT staff or its consultants.
Study area – In this study, the transportation study area is synonymous with the OCARTS area; also known as metropolitan planning area and the transportation management area (TMA).
Superfund – Also known as CERCLA (Comprehensive Environmental Response Compensation and Liability Act). A Federal law that provides for compensation, cleanup, and emergency response for hazardous substances released into the environment and the cleanup of hazardous waste disposal sites.
Traffic Analysis Zone (TAZ) – A special area delineated by local transportation officials for tabulating traffic related data especially journey-to-work and place of work statistics. A TAZ usually consist of one or one or more census blocks, block groups, or census tracts.
Traffic Count – In transportation, a process that tallies a particular movement of people or vehicles past a given point during a stated time period. It may be a directional or a two-way value.
Transit Oriented Development (TOD) – Transit-oriented development (TOD) is the functional integration of land use and transit via the creation of compact, walkable, mixed-use communities within walking distance of a transit stop or station. A TOD brings together people, jobs, and services and is designed in a way that makes it efficient, safe, and convenient to travel on foot or by bicycle, transit, or car.
Transportation Demand Management – Tools designed to maximize the people-moving capability of the transportation system by increasing the number of people in each vehicle or by influencing the time of, or need to travel. To accomplish these demand-side changes, TDM programs must rely on incentives or disincentives to make the shifts in behavior attractive. Specific TDM strategies include public support, employer based support, telecommunications, land use policies, and public policy such as pricing or other regulation.
Travel Demand Modeling or Travel Forecasting – Used by transportation planners for simulating current travel conditions such as roadways, transit, and high-occupancy vehicles. 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.
Transportation Equity Act for the 21st Century (TEA-21) – TEA-21 was signed into law on June 9, 1998, and was effective for a six-year period (federal fiscal years 1998 through 2003). TEA 21 built upon the initiatives and structure established in ISTEA. New areas of program focus include safety, environmental quality, and ITS research and development. TEA-21 was replaced by SAFETEA LU.
Transportation Improvement Program (TIP) – The TIP is a financially constrained short range document that lists specific projects to be implemented within the transportation planning area. Projects included in the TIP must be consistent with the long-range plan, and inclusion of projects in the TIP is a requirement for the use of federal transportation funding.
Transportation Management Area (TMA) – An urbanized are over 200,000 in population as determined by the latest decennial census. The TMA designation applies to the entire Metropolitan Planning Area.
Transportation System Management (TSM) – That part of the urban transportation planning process undertaken to improve the efficiency of the existing transportation system. The intent is to make better use of the existing transportation system by using short term, low capital transportation improvements that generally cost less and can be implemented more quickly than large, capital intensive options.
Trip – A one way movement of a person or vehicle between two points for a specific purpose; sometimes called a one way trip to distinguish it from a round trip.
Trip purpose – The primary reason for making a trip; for example, work, shopping, medical appointment, recreation.
Unified Planning Work Program (UPWP) – The annual management plan for a metropolitan planning program designed to coordinate the planning activities of all participants in the planning process.
Urban transportation planning process – The federally required planning process for urbanized areas that is aimed at developing programs to meet a region's transportation needs by analyzing the existing system and preparing plans and studies in a comprehensive, continuing, and cooperative manner. Also known as the metropolitan planning process, it results in several documents including a unified planning work program (UPWP), a transportation improvement program (TIP), and a long-range regional transportation plan (LRP).
Urbanized Area (UZA) – An area that contains a city of 50,000 or more population plus surrounding area meeting density criteria as defined by the U.S. Census Bureau.
Vehicle Hours of Travel (VHT) – On roadways, a measurement of the total hours traveled by all vehicles in the area for a specified time period. It is calculated by multiplying the number of vehicles times the number of hours traveled in a given area or on a given roadway during the time period.
Vehicle Miles of Travel (VMT) – On roadways, a measurement of the total miles traveled by all vehicles in the area for a specified time period. It is calculated by multiplying the number of vehicles times the number of miles traveled in a given area or on a given roadway during the time period. In transit, the number of vehicle miles operated on a given route or line or network during a specified time period.
Volume – In transportation, the number of units (passengers or vehicles) that pass a point on a transportation facility during a specified interval of time, usually one hour.
Volume to Capacity Ratio (V/C Ratio) – A measure of the congestion level of streets and highways which compares the vehicular carrying capacity of a roadway with the actual volume of vehicles which travel the roadway, within a specified period of time.
Year of Expenditure (YOE) – Revenue and cost estimates that reflect inflation rate(s) anticipated for a future year or group of years. YOE dollars are required under SAFETEA-LU to demonstrate financial constraint of the metropolitan long-range plan and TIP.
Acronyms and Abbreviations
AASHTO American Association of State Highway Transportation Officials
ACOG Association of Central Oklahoma Governments
ADA Americans with Disabilities Act of 1990
ADT Average Daily Traffic
APTAC Areawide Planning and Technical Advisory Committee
B/C Benefit to Cost
BRT Bus Rapid Transit
BEA Bureau of Economic Analysis
CAA Clean Air Act
CAC Citizens Advisory Committee
CART Cleveland Area Rapid Transit
CBD Central Business District
CMP Congestion Management Process
CMAQ Congestion Mitigation and Air Quality Improvement Program
COTPA Central Oklahoma Transportation and Parking Authority
CRT Commuter Rail Transit
CTPP Census Transportation Planning Package
DEIS Draft Environmental Impact Statement
EPA Environmental Protection Agency
FHWA Federal Highway Administration
FTA Federal Transit Administration
GAM Growth Allocation Model
GIS Geographic Information Systems
HOV High Occupancy Vehicle
IMS Intermodal Management System
ISTEA Intermodal Surface Transportation Efficiency Act of 1991
ITPC Intermodal Transportation Policy Committee
ITS Intelligent Transportation Systems
ITTC Intermodal Transportation Technical Committee
LOS Level of Service
LRP Long range (Transportation) Plan
LRTP Long Range Transit Plan
MOU Memorandum of Understanding
MPO Metropolitan Planning Organization
MSA Metropolitan Statistical Area
NEPA National Environmental Policy Act
NOX Nitrogen Oxide
NPTS National Personal Transportation Survey
OCARTS Oklahoma City Area Regional Transportation Study
ODOC Oklahoma Department of Commerce
ODOT Oklahoma Department of Transportation
OESC Oklahoma Employment Security Commission
OTA Oklahoma Turnpike Authority
RTDM Regional Travel Demand Model
PIP Public Involvement Process
RTD Regional Transit Dialogue
ROW Right-of-Way
SAFETEA-LU Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users
SIC Standard Industrial Classification
SOV Single Occupancy Vehicle
SPR State Planning and Research Program
STIP Statewide Transportation Improvement Program
TAZ Traffic Analysis Zone
TDF Travel Demand Forecasting
TDM Transportation Demand Management
TEA-21 Transportation Equity Act for the 21st Century of 1998
TIP Transportation Improvement Program
TMA Transportation Management Area
TOD Transit Oriented Development
TRB Transportation Research Board (of the National Academy of Sciences)
TSM Transportation Systems Management
UPWP Unified Planning Work Program
UZA Urbanized Area
V/C Volume to Capacity
VHT Vehicle Hours of Travel
VMT Vehicle Miles of Travel
YOE Year of Expenditure
