Below is a list of terms and acronyms that you may encounter in technical reports, plans, data, informational materials, or conversations during the I-20 DeKalb HOV project.

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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.

Atlanta Regional Commission (ARC): The Metropolitan Planning Organization for the 10-county Atlanta Region.

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 a group of people such as coworkers to share the duty of driving to and from somewhere.

Categorical Exclusion (CE): Actions that do not individually or cumulatively have a significant social, economic, or environmental effect and are excluded from the requirement to prepare an EA or EIS under NEPA.

Clean Air Amendments of 1990 (CAAA): 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 cuts down on the amount of weaving and transitioning that occurs between exits located within a short amount of distance from one another.

Commute: (n) The amount of time it takes to travel regularly from one place to another, especially between home and work. (v) 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 lane.”

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 will describe 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 thru, 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.

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.

Environmental Assessment (EA): This document is prepared to determine if there will or will not be significant impacts associated with a project. This 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 reviews and studies all impacts. Generally, these studies could take several years to complete.

Environmental Justice (EJ): The fair treatment and meaningful involvement of all people regardless of race, color, national origin, or income by identifying and addressing the effects of transportation projects on the public, especially high or adverse impacts to minority or low-income populations.

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 is an HOV lane.

Freeway: A divided highway having two or more lanes for the 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.

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 would be a road to be used only by a trolley or a bus or a rail lane for heavy trail.

High Occupancy Vehicle Lanes (HOV): Lanes dedicated for exclusive use by multi-occupant vehicles such as buses and vanpools. In Atlanta, there are over 90 miles of HOV lanes on I-85, I-75 and I-20 east. In the next 10 years, as much as 45 more miles covering I-85 south, I-20 west, SR 400 and I-285 could come online.

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.

Inspection and Maintenance (I&M): Refers to legislated requirements for vehicle inspection and maintenance for air quality assurance. Georgia's I&M program was implemented by the Georgia Environmental Protection Division (EPD) in 2000. GA EPD also monitors the Inspection program statewide.

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 and SAFETEA-LU.

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 which established 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.

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

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 people. ARC is the MPO for the 10-county Atlanta Region.

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.

Multi-modal: 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 US EPA 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 of 1969 (NEPA): 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 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, intermodal transportation facilities and routes of particular importance to local governments.

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

Nonattainment Areas: Geographical areas, as defined by US EPA, whose air quality does not meet federal air quality standards designed to protect public health.

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 the children and the elderly.

Plan Development Process (PDP): A document maintained by the Preconstruction Division that is provided as guidance within the Georgia Department of Transportation 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.

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

Regional Strategic Arterial System (RSAS): Identifies key arterials within corridors carrying high traffic volumes and 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.

Right of Way (ROW): is an area which usually holds the public utilities (both overhead and underground) and acts as a buffer between transportation infrastructure (for example-road or rail) and private property.

SOV: A single occupant vehicle. It has one occupant, the driver.

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

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

Transportation Demand Management (TDM): Low cost ways to reduce demand by automobiles on the transportation system, such as programs to promote telecommuting, flextime and ridesharing.

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.

Unified Planning Work Program (UPWP): An instrument for coordinating transportation and comprehensive planning in a metropolitan region. Its intent is to broaden the MPO's awareness of local activities and plans that may impact the surface transportation system. It also ensures that planned improvements are based on a common set of existing conditions and forecasts. Lastly, the UPWP guarantees all key decisions affecting growth and development within the metropolitan area are coordinated thus lessening the potential for duplicable or conflicting planning efforts of member agencies.

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

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

VISION 2020: A planning effort that has guided the development of the Regional Transportation Plan (RTP) by providing goal statements from a shared regional vision. Transportation projects have been evaluated and prioritized based on these goals as well as other guidelines.

Helpful Acronyms

ARC: Atlanta Regional Commission
ATMS: Advanced Transportation Management System
CAAA: Clean Air Act Amendments of 1990
CCT: Cobb Community Transit
CFR: Code of Federal Regulations
CMAQ: Congestion Mitigation and Air Quality Improvement Program
CMS: Congestion Management System
CST: Construction
EJ: Environmental Justice
EPD: Environmental Protection Division (State of Georgia)
EX: Exempt
FHWA: Federal Highway Administration
FTA: Federal Transit Administration
GBT: Georgians for Better Transportation
GDOT: Georgia Department of Transportation
GF: Grandfathered
GRTA: Georgia Regional Transportation Authority
HOV: High Occupancy Vehicle
Interagency MOA: Interagency Memorandum of Agreement
ISTEA: Intermodal Surface Transportation Efficiency Act of 1991
ITS: Intelligent Transportation System
MARTA: Metropolitan Atlanta Rapid Transit Authority
MPO: Metropolitan Planning Organization
NAAQS: National Ambient Air Quality Standards
NEPA: National Environmental Policy Act of 1969
NHS: National Highway System
NOx: Nitrogen Oxides
OEL: Office of Environment/Location
PE: Preliminary Engineering
PSG: Partnership for a Smog-Free Georgia
ROW: Right-of-Way
RSAS: Regional Strategic Arterial System