Transportation Terms
Alternatives Analysis - A detailed study of alternative transportation improvements to address specific issues in a corridor. All feasible alternatives are investigated, and the best approach is selected for implementation. An Alternatives Analysis was required by the Federal Transit Administration (FTA) as the first step in the Environmental Impact Statement process before Major Investment Studies.
Alternative Transportation - Modes of transportation other than the single-passenger motor vehicle, including but not limited to carpools, vanpools, buspools, public transit, walking, and bicycling.
Ambient Air Quality - The concentration of chemicals and other elements in the air determined over a set time period.
Arterial Street or Roadway - A major thoroughfare serving higher speed through trips, with limited access to adjacent property.
Average Daily Traffic (ADT) - The average number of vehicle trips generated during a 24-hour period from a specific site or area. This term also applies to traffic volumes on a roadway over a 24-hour period.
Average Vehicle Occupancy (AVO) - The total number of persons in all vehicles divided by the number of vehicles traveling past a selected point during a predetermined time period. AVO is usually expressed to two or three significant decimal places, such as 1.2 or 1.26.
Average Vehicle Ridership (AVR) - The average number of employees who report to a work site divided by the average number of vehicles driven by these employees, calculated for an established time period. This calculation recognizes vehicle trip reductions from telecommuting, compressed work weeks, and non-motorized transportation.
Benefit-Cost Ratio - Analysis tool used to estimate the anticipated benefits for a specific project. Estimated by dividing the dollars of discounted benefits achievable by the discounted costs.
Bid and Bid Process - The process of a public agency requesting proposals for a specific project or scope of work and the response from an individual or firm to secure a contract.
Capacity - The maximum number of vehicles (vehicular capacity) or persons (person capacity) that can pass over a given section of roadway in one or both directions during a given period of time under a prevailing management strategy that assures an acceptable level of free-flow service, usually expressed as vehicles per hour or persons per hour.
Capital Cost - The costs associated with the purchase, development or construction of fixed assets such as land, roadways, guideways, stations, buildings, and vehicles.
Commuter Rail and Commuter Rail Transit - Passenger rail service which is often operated on existing railroad rights-of-way or on trackage shared with freight railroads. Commuter rail is characterized by long distance trips, faster operating speeds, and limited service, with longer distances between stops.
Congestion Pricing - The concept of charging for the use of a transportation facility, such as a roadway, based on the level of traffic congestion. The greater the level of congestion, which usually occurs during the morning and afternoon peak-periods, the higher the cost to use the facility.
Corridor - A geographical area usually defined by a freeway, roadway, or other physical element and its immediate surrounding area, including collector routes, that has similar characteristics.
Cost-Benefit Analysis - An analytical technique that computes the costs and benefits, measured in monetary terms, of a proposed transportation improvement or policy action. Identified losses and gains experienced by society are included, and the net benefits created by an action are calculated. Alternative actions are compared to assist in the selection of those that yield the greatest net benefits or benefit-cost ratio.
Environmental Assessment (EA) - A study to determine the potential impacts on the environment from a project as required by the National Environmental Policy Act of 1969.
Environmental Impact Statement (EIS) - A comprehensive study of all the potential impacts of a project funded with federal dollars as required by the National Environmental Policy Act of 1969.
Equity - A normative measure of the fairness of a transportation project or a strategy among all users.
Feasibility Study - A study to determine the suitability of alternative projects or actions.
Fixed Guideway Transit System - Any transit system with vehicles that operate on a permanent or a fixed guideway. Examples include heavy rail, light rail, transit, monorail, and other related systems.
Grade - A raise in elevation within a specific distance. A 1-percent grade is a 1 meter raise in elevation over 100 meters of horizontal distance.
High-Occupancy Vehicle (HOV) Lane - A lane designated for exclusive use by high-occupancy vehicles (HOVs) for all or a portion of the day. An HOV lane may be on a freeway, roadway, arterial street, or in a separate right-of-way.
Infrastructure - All fixed components of a transportation system including roadways and bridges, park-and-ride lots, fixed transit components, and other elements.
Intelligent Transportation Systems (ITS) - The application of a wide range of advanced technologies to enhance the operation and management of the surface transportation system.
Interchange - The system of grade separated ramps connecting two or more freeways, toll roads, or other exclusive roadways, or connecting a roadway to an interstate.
Intermodal - The integration of multiple modes in a corridor or area.
Joint Development - Projects that involve the joint use or improvement of a piece of property. Joint developments usually involve the public and private sectors working together on a project, but they may also include public/public partnerships.
Letting - The process by which NCDOT requests and decides on bids from competing companies for work on transportation projects.
Light Rail Transit (LRT) - A mode of transit that operates on steel rails and obtains its power from overhead electrical wires. LRT may operate in single or multiple cars on separate rights-of-way or in mixed traffic.
Mass Transit and Mass Transportation - Transportation provided by public or private operators by bus, rail, ferry, or other mode that operates on a regular basis, and serves large numbers of riders.
Mode - A particular form of travel conveyances, including buses, automobiles, carpools, vanpools, single occupant vehicles, walking, bicycling, rail, air, and water-borne vessels.
Multimodal - More than one mode operating in a corridor or area.
Non-Attainment Area - A geographic area that does not meet the National Ambient Air Quality Standards for one or more pollutants.
Off-Peak Period - The period of time outside the peak commuting period, usually the midday, evening, night, and early morning.
Ozone - A highly reactive form of oxygen with a pungent odor that is formed in the atmosphere by a series of photochemical reactions involving oxides of nitrogen and reactive organic gases in the presence of sunlight. National Ambient Air Quality Standards have been established for ozone.
Peak Period - The time period in the morning and in the afternoon when the heaviest demand occurs on a given transportation facility or corridor. Usually two or more hours.
Public Transit and Public Transportation - Passenger transportation service to the public on a regular basis using vehicles that transport more than one person for compensation, usually but not exclusively over a set route or routes from one fixed point to another. Routes or schedules of this service may be predetermined by the operator or may be determined through a cooperative arrangement.
Right-of-Way - The area or property reserved for a specific transportation function such as a roadway or transit guideway.
Single Occupant Vehicle (SOV) - A motor vehicle occupied by only one person.
Smog - A general term used to describe the irritating haze produced by photochemical reactions in the atmosphere.
Transit - General term referring to all vehicles and systems that move more than one individual, includes carpools, vanpools, minibuses, buses, coaches, LRT, heavy rail, and commuter rail.
Vehicle Miles of Travel (VMT) - The total distance traveled in miles by all motor vehicles of a specific group in a given area at a given time.