List of Terms Explained


Alternatives Analysis: During the environmental process, the consideration and discussion of all reasonable alternatives or the reasonable range of alternatives at a comparable level of detail to avoid any indication of a bias towards a particular alternative(s). Although the "no-build alternative" (which might include short-term minor activities) might not seem reasonable, it must always be included in the analysis. Alternatives analysis indicate why and how the particular range of project alternatives was developed, including what kind of public and agency input was used, and why and how alternatives were eliminated from consideration. It must be made clear what criteria were used to eliminate alternatives, at what point in the process the alternatives were removed, who was involved in establishing the criteria for assessing alternatives, and the measures for assessing the alternatives' effectiveness.
In reference to FTA’s New Starts Program,an alternatives analysis study is an early step in the project development process for projects that may request funding. The study must be consistent with current FTA Section 5309 "New Starts" requirements and be comprised of the following steps: (1) Review previous and related studies and findings and incorporate the previous analysis into the development of key project elements, (2) Define the project purpose and establish the project goals and objectives, (3) Define project corridor, effected areas of a new service, and proposed alignments, (4) Develop a list of alternatives as well as a screening process that will ultimately be used to select a locally preferred alternative (LPA), (5) Develop detailed information for each of the short list alternatives, including ridership, operating plans, capital costs, operations and maintenance costs, environmental factors, and (6) Conduct public meetings and solicit public input throughout the process.

Ambient Air: USEPA. The portion of the atmosphere, external to buildings, to which the general public has access.

Americans with Disabilities Act (ADA): Federal legislation passed in 1990 that prohibits discrimination on the basis of disability. Further requires all transportation facilities must be accessible.

Arterial: A major thoroughfare that is vital for moving people and goods; feeds into the interstate and freeway systems.

Attainment: USEPA. Any area that meets the national primary or secondary ambient air quality standard for the pollutant.

Barrier-Separated Facility: A special purpose lane, such as an HOV lane, that is physically separated by guardrail or concrete median barriers from adjacent mixed-flow freeway lanes. A barrier or buffer may separate the opposing direction of traffic within a barrier-separated facility.

Baseline Conditions: In transportation, the existing environmental physical conditions in the vicinity of the project when notice to proceed is issued, which provide baseline physical conditions against which project-related changes can be compared. In reference to FTA’s New Starts program, the baseline alternative must include in the project corridor all reasonable cost-effective transit improvements short of investment in the new start project. Depending on the circumstances and through prior agreement with FTA, the baseline alternative can be defined appropriately in one of three ways. First, where the adopted financially constrained regional transportation plan includes within the corridor all reasonable cost-effective transit improvements short of the new start project, a no-build alternative that includes those improvements may serve as the baseline. Second, where additional cost-effective transit improvements can be made beyond those provided by the adopted plan, the baseline will add those cost-effective transit improvements. Third, where the proposed new start project is part of a multimodal alternative that includes major highway components, the baseline alternative will be the preferred multimodal alternative without the new start project and associated transit services. Prior to submittal of a request to enter preliminary engineering for the new start project, grantees must obtain FTA approval of the definition of the baseline alternative.

Build Alternative(s): The alternative(s) being evaluated as the proposed action during the environmental review process.

Bus Rapid Transit (BRT): A flexible and reliable bus system with train-like operating characteristics that can be used on its own guideway, in HOV lanes or on city streets.

Busway: A special roadway designed for exclusive use by buses. It may be constructed at, above, or below grade and may be located in separate rights-of-way or within highway corridors.

Capacity: The rate of vehicular or person flow that can be expected to cross a point on a lane or roadway during a specific period.

Carpool: An arrangement made by two or more people to share a ride using their personal vehicles.

Carpool Lane: A term used to refer to high-occupancy vehicle lanes in some regions of the United States.

Categorical Exclusion (CE): A categorical exclusion is the lowest level of environmental analysis and documentation that may be required under NEPA regulations. This occurs when a proposed project or action is categorically excluded from a detailed environmental analysis because it will not significantly impact the environment. A specific list of CE actions normally not requiring NEPA documentation is set forth in 23 CFR 771.117(c). Other projects, pursuant to 23 CFR 771.117(d), may also qualify as CEs if appropriately documented.

Clean Air Amendments of 1990 (CAA): Federal legislation that establishes acceptable levels of certain criteria pollutants.

Collector: Intended to balance access and mobility considerations by serving through movement as well as access to land. Collectors connect traffic on highways and arterials to local streets and adjacent land.

Collector Distributor (CD): A CD system appears on a freeway system. The local and through traffic is separated by a median or wall. The use of CDs reduces the amount of weaving and transitioning that occurs between exits located within a short amount of distance from one another.

Community Improvement District (CID): A geographically defined district in which commercial and industrial property owners vote to impose a self-tax to fund community improvements. Residential and agricultural properties are included in the CID boundaries, but are not taxed. The revenue generated by the district is used to implement a variety of projects and programs that will serve to benefit the immediate area.

Commute: The amount of time it takes to travel regularly from one place to another, especially between home and work.

Commuter: A person that travels regularly between places, especially between home and work.

Commuter Lane: See “High-Occupancy Vehicle (HOV) Lanes.”

Concept: An alternative or “footprint” for a project that is evolving and being revised based on the project need and purpose and potential project impacts until it is approved by Georgia DOT and becomes the “preferred alternative” or approved concept.

Concept Development Stage: A stage in the Preliminary Engineering phase of the Georgia DOT plan development process. The objective of the Concept Development Stage is to develop a Concept Report that describes a recommended project “footprint” (or “Build Alternative” or “No-Build Alternative”) that addresses the project’s “Need and Purpose” after preliminary traffic and operational studies, accident analysis, determination of project deficiencies, planning requirements, development of environmental constraints (an on-site, drive-through screening of the project area), study of alternatives, permit requirements, social and economic considerations, utility considerations, right-of-way impacts, and other analyses have been made.

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

Conservation Cluster Development: Conservation/Cluster Development Subdivision is a subdivision design that preserves important natural features such as open fields, hilltops, forests, and rivers. Conservation/Cluster Development Subdivision locates houses on smaller parcels of land, and the land that would have been allocated to individual lots is preserved in its natural state as open space for the subdivision. This open space is permanently set aside for public or private use and will not be developed. Typically, road frontage, lot size, setbacks, and other traditional subdivision design requirements are redefined to permit the developer to preserve water features, natural areas, historical sites, or other unique characteristics of the land.

(CCDOD) - Conservation Cluster Development Overlay Zoning District: See above: Conservation Cluster Development:

Corridor: In planning, a broad geographical area of land that follows a general direction flow or connects major sources of trips. It may contain a number of streets, highways, transit lines and routes. It generally follows an interstate, freeway or major roadway.

Development of Regional Impact (DRI): A large-scale development project, regardless of the mix of land uses, which is likely to impact the transportation network and environment beyond the limits of the jurisdiction in which it is being constructed.

Diamond Lane: A term used to refer to high-occupancy vehicle lanes in some regions of the United States because of the diamond symbol on signing and pavement markings.

Draft Environmental Impact Statement (DEIS): A draft version of the Environmental Impact Statement that documents the potential social, economic and environmental impacts of a proposed project or action and proposed measures to mitigate those impacts. The draft is released to the public and impacted agencies for review and comment.

Environmental Assessment (EA): Completion of an environmental assessment is the second level of analysis and documentation under NEPA. This document is prepared to determine whether the proposed project or action will significantly affect the environment. If not, a finding of no significant impact (FONSI) may be issued. The FONSI may also address actions that will be taken to reduce potentially significant impacts. However, if significant environmental impacts will occur, an Environmental Impact Statement (EIS) is prepared. The EA document is subject to FHWA approval and must be made available for public inspection and comment.

Environmental Impact Statement (EIS): This document is prepared for projects that will have significant social, economic, or environmental effects and involves review and study all impacts. Generally, these studies could take several years to complete.
This is the highest level of environmental analysis and documentation in the NEPA process. An EIS assesses the environmental impacts of a proposed project or action and its alternatives. The EIS includes public input as well as input from other federal agencies and outside parties during preparation. The draft EIS is open for public comment when complete. If significant impacts are expected, an EIS may be prepared without having to first prepare an EA. After a final EIS is prepared, a public record of decision (ROD) is prepared addressing how the findings of the EIS, including consideration of alternatives, were incorporated into the final decision-making process.

Environmental Justice (EJ): The concept of determining whether a governmental project, program or policy will disproportionately and adversely affect a disadvantaged community or population. The 1994 Federal Executive Order 12898 requires such analysis as well as involvement of specific minority and low-income populations in the project planning process.

Expressway: A divided highway facility usually having two or more lanes for the exclusive use of traffic in each direction and partial control of access.

Facility: The means by which a transportation mode is provided. For example, a sidewalk is a facility as well as an HOV lane.

Federal Highway Administration (FHWA): The division of the U.S. Department of Transportation that provides federal financial and technical assistance in planning, constructing and upgrading the nation’s network of highways, roads and bridges.

Federal Transit Administration (FTA): The division of the U.S. Department of Transportation that provides federal financial and technical assistance in planning, constructing and upgrading transit systems at the local, regional and national levels.

Final Environmental Impact Statement (FEIS): The final version of the EIS that is prepared and submitted after comments on the Draft EIS are received and reviewed. The Final EIS must contain the lead agency’s responses to all received comments and must discuss any opposing views on issues raised. The FEIS is filed with the U.S. Environmental Protection Agency, and a 30-day time period is allotted for public review. Once the FEIS is submitted, the lead agency prepares a Record of Decision (ROD) on the proposed action.

Freeway: A divided highway having two or more lanes for the free and exclusive use of traffic in each direction and full control of access. The freeway is the only type of highway intended to provide complete "uninterrupted" flow.

Frontage Road: A roadway that parallels a major transportation facility such as a freeway. It serves to collect and distribute traffic along the major facility without impeding flow along the freeway.

Functional Classification: Streets provide two distinct functions: mobility (through movement) and access to land. Functional classification is a hierarchical ranking based on the degree of mobility and access that a street provides. Streets are generally classified as arterials, collectors and local streets.

General-Purpose Lane: A lane that accommodates all types of vehicular traffic on the highway.

Grade: The slope (ratio of change in elevation to change in distance) of a roadway typically given in percent. For example, a 2% grade represents 2 feet of elevation change over a 100-foot distance.

Guideway: A travel way, separated from other transportation modes, that supports a form of transit. An example is a road to be used only by a trolley or a bus or a rail lane for heavy trail.

High-Occupancy Toll (HOT) Lanes: Lanes that combine HOV lanes with tolling to allow non-HOV vehicles to use HOV lanes by paying a toll. The lanes are “managed” through congestion pricing to maintain free flow conditions even during the height of rush hours.

High-Occupancy Vehicle (HOV) Lanes: Lanes restricted to vehicles, including buses, with more than one occupant. HOVs encourage ridesharing and can improve transit operations. HOV lanes can be limited to two, three, or more occupants per vehicle to regulate traffic flow.

Infrastructure: In transportation planning, the fundamental facilities and elements of a transportation system serving a county, city, or area, such as roads, rails, sidewalks, and traffic signals.

Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA):  Federal legislation that authorizes federal highway, highway safety, transit, and other surface transportation projects. The bill was signed into law in December 1991 and expired on September 30, 1997.  (Also see "Transportation Equity Act for the 21st Century.")

Inspection and Maintenance (I&M): Refers to legislated requirements for vehicle inspection and maintenance for air quality assurance.

Intermodal: Interconnectivity between various types (modes) of transportation.

Intermodal Surface Transportation Efficiency Act (ISTEA): Landmark federal legislation signed into law in 1991. It made broad changes in the way transportation decisions are made by emphasizing diversity and balance of modes as well as the preservation of existing systems and construction of new facilities. The law expired in 1997, but much of the program is carried forward by TEA-21.

Land Use: Refers to the manner in which portions of land or the structures on them are used, such as commercial, residential, industrial, etc.

Land Use Plan: A plan that establishes strategies for the use of land to meet identified community needs.

Level of Service (LOS): A qualitative measure describing operational conditions within a traffic stream and motorists' perceptions of those conditions. For example, LOS A is free flow; B: stable flow; C: stable flow but beginnings of congestion; D: high density but stable flow; E: at capacity level; and F: stop and go.

Linked Trip: Travel Demand Modeling term used to describe a trip from its beginning to its end regardless of the mode types (walk, bus, car, etc.) used.

Local Street: Emphasizes access to land. Local streets provide access between land and the adjacent street system.

Locally Preferred Alternative (LPA): The alternative selected by local decision-makers as the preferred solution to a corridor’s identified needs. It is part of the FTA’s Alternatives Analysis Process, which requires an analysis of the LPA as a component of the environmental review.

Managed Lanes: Managed lanes are used in conjunction with general-purpose lanes to improve traffic flow on the overall highway system. A managed lane is one where access to the lane is restricted based on occupancy, tolls and/or vehicle classification. Examples of managed lanes include high-occupancy vehicle (HOV) lanes, high-occupancy toll (HOT) lanes, and truck-only lanes (TOLs).

Metropolitan Planning Organization (MPO): A federally required planning body responsible for transportation planning and project selection in its region; the governor designates an MPO in every urbanized area with a population of over 50,000.

Mobility 2030: The most recent long-range Regional Transportation Plan adopted by the Atlanta Regional Commission for dealing with the current and expected demands being placed on the region’s transportation system.

Mode: A particular form of travel, e.g., walking, traveling by automobile, traveling by bus, traveling by train.

Multimodal: Refers to the availability of multiple transportation options, especially within a system or corridor. A concept embraced in ISTEA, a multimodal approach to transportation planning focuses on the most efficient way of getting people or goods from place to place, be it by truck, train, bicycle, automobile, airplane, bus, boat, foot or even computer modem.

National Ambient Air Quality Standards (NAAQS): Issued by USEPA and determines the amount of total emissions of criteria pollutants that can be produced in a geographic location by transportation facilities.

National Environmental Policy Act (NEPA) of 1969: An act that requires federal agencies to consider the potential economic, social, and environmental consequences of projects and proposals, document the analysis, and make this information available to the public for comment prior to project implementation.

National Highway System (NHS): Includes the interstate system and other routes identified as having strategic defense characteristics as well as routes providing access to major ports, airports, public transportation, and intermodal transportation facilities, and routes of particular importance to local governments.

New Starts (from FTA): The New Starts Program is a funding source for local transit “guideway” projects, such as rapid rail, light rail, commuter rail, people movers, and exclusive facilities for buses and other high-occupancy vehicles (such as bus rapid transit). Projects must compete nationally for New Starts funding.

Need and Purpose Statement: The National Environmental Policy Act of 1969 (NEPA) requires the development of a Project Need and Purpose Statement as part of the environmental documentation for projects that receive federal funding. This statement provides the basis for evaluating project alternatives. For transportation projects, the Project Need and Purpose Statement describes the transportation-related problem(s) in an area and explains the purpose of the project, such as solving transportation needs, achieving state or regional transportation system objectives, or accomplishing land use, economic development, or growth objectives.

Nitrogen Oxides (NOx): (pronounced "knocks") Emission that forms from combustion of fossil fuels. NOx reacts with heat and sunlight to produce smog, especially in New York's hot, dry months between July and September.

No-Build Alternative: Serves as the baseline for the environmental analysis documented in the Draft Environmental Impact Statement to evaluate future conditions if a proposed project is not built.

Nonattainment Area (from USEPA): Any area that does not meet (or that contributes to ambient air quality in a nearby area that does not meet) the national primary or secondary ambient air quality standard for the pollutant.

Ozone: A colorless gas formed when volatile organic compounds and NOx combine in sunlight. There are two types of ozone. The "good" ozone protects the earth from the sun's harmful ultraviolet rays. The "bad" ozone usually lingers at ground level and can cause respiratory problems, especially in children and the elderly.

Park-and-Ride Lot: Parking facilities at transit stations, bus stops, and highway on-ramps to facilitate transit and rideshare use. Some include bicycle parking. Parking is generally free.

Peak-Hour Service: Weekday a.m. and p.m. service during commute hours, which carry a maximum number of passengers.

Plan Development Process (PDP): A document maintained by the Preconstruction Division of the Georgia Department of Transportation to provide guidance in developing project plans and fulfilling its mission to provide a safe, efficient, and sustainable transportation system through dedicated teamwork and responsible leadership supporting economic development, environmental sensitivity, and improved quality of life.

Preferred Alternative: The project “footprint” or alternative recommended in the concept report during the Concept Development Stage and approved by Georgia DOT. (Also see Concept Development Stage.)

Program: A system of funding for implementing transportation projects or policies.

Public Information Open House/Public Hearing Open House (PIOH/PHOH): A public gathering for residents to learn about and provide input on transportation projects that may impact their community.

Record of Decision (ROD): A written public record issued by the lead federal agency once all requirements of the environmental review process have been satisfied. It explains the reasoning behind why a particular course of action was chosen, identifies alternatives that were considered, and summarizes specific mitigation measures that will be incorporated into a project.

Regional Strategic Arterial System (RSAS): Identifies key arterials within corridors carrying high traffic volumes that are important to moving people, goods and services through the region. RSAS streets are monitored for congestion, safety and land use. These roads receive primary consideration in planning and funding.

Rideshare: Refers to carpooling and vanpooling (the term is sometimes also applied to public transit, particularly commuter express bus).

Right-of-Way (ROW): An area that usually holds public utilities (both overhead and underground) and acts as a buffer between transportation infrastructure (e.g., road or rail) and private property.

Single-Occupant Vehicle (SOV): A vehicle that has one occupant, the driver.

Stakeholder: An individual or organization involved in or potentially affected by a proposed transportation project. This may include the public, elected government officials, local government staff, and state and federal agency staff as well as non-profit organizations or special interest groups.

State Road and Tollway Authority (SRTA): State of Georgia agency serving as one of the financing arms for state transportation agencies. SRTA is empowered to sell bonds for transportation projects and to manage the state’s toll road facilities. Currently, the agency manages the state’s only toll road, Georgia 400.

Teleworking: The ability to do your work at a location other than your "official duty station." (Aso called telecommuting.)

Traffic Incident Management Enhancement (TIME) Task Force: A task force formed to address the critical issues related to incident management in the Atlanta region. This task force is made up of concerned incident responders from transportation agencies, fire, rescue, police, towing, emergency medical services, etc.

Transportation Control Measure (TCM): A strategy to reduce driving or smooth traffic flows in order to reduce automobile emissions and resulting air pollution. Examples of TCMs include HOV lanes, new or increased transit service, or a program to promote carpools and vanpools.

Transportation Demand Management (TDM): a general term for strategies that result in more efficient use of transportation resources, while providing a wide variety of mobility options for those who wish to travel.

Transportation Enhancement (TE) Activities: A funding category created in the 1991 Intermodal Surface Transportation Efficiency Act (ISTEA). Ten percent of STP monies must be set aside for projects that enhance the compatibility of transportation facilities with their surroundings.

Transportation Equity Act for the 21st Century (TEA-21):  Federal legislation that authorizes Federal highway, highway safety, transit, and other surface transportation programs. The bill was signed into law on June 9, 1998, and covers the period of October 1, 1997 through September 30, 2003. TEA-21 succeeds the Intermodal Surface Transportation Efficiency Act (ISTEA), which expired on September 30, 1997. 

Transportation Management Association (TMA): Private, non-profit, member-controlled organizations that provide transportation services in a particular area. The Atlanta Region has eight formal TMAs.

Transportation System Management (TSM): Actions that control or improve the movement of cars and trucks on the highway system and buses on the transit system. It includes the coordination of the available transportation systems for more efficient operations.

Truck Only Lanes (TOL): Managed lanes primarily intended for the use of heavy trucks and are typically barrier separated where feasible. These lanes would primarily serve “through-trucks” which do not have local deliveries. TOL improve safety and operation by physically separating heavy trucks from automobile traffic. TOL also provides truckers with faster and more reliable travel time. Truck Only Lanes, when tolled, are typically referred to as Truck only Toll (TOT) lanes.

Unclassifiable: USEPA. Any area that cannot be classified on the basis of available information as meeting or not meeting the national primary or secondary ambient air quality standard for the pollutant.

Unlinked Trip: A trip on a particular link; a subset of a linked trip.

Vanpool: A group of 7 to 15 people who commute together on a regular basis in a van.

Vehicle Miles Traveled (VMT): On highways, a measurement of the total miles traveled by all vehicles in an area for a specified time period.