Skip to content
U.S. Department of Transportation
People in shadow


You may need the Adobe Acrobat Reader to view the PDFs on this page.

Accessibility. The ease of reaching valued destinations, such as jobs, shops, schools, entertainment, and recreation.47

Active Transportation. Any self-propelled, human-powered mode of transportation.48

Brownfield revitalization. With certain legal exclusions and additions, the term "brownfield site" means real property, the expansion, redevelopment, or reuse of which may be complicated by the presence or potential presence of a hazardous substance, pollutant, or contaminant.49 Brownfield cleanup and redevelopment activities improve communities as dilapidated and often dangerous buildings are demolished or renovated and contaminated soil is removed and replaced. Such improvements create a sense of possibility and renewal in the community.50

Bus Rapid Transit (BRT) Systems. BRT is an innovative, high capacity, lower cost public transit solution that can significantly improve urban mobility. This permanent, integrated system uses buses or specialized vehicles on roadways or dedicated lanes to quickly and efficiently transport passengers to their destinations, while offering the flexibility to meet transit demand. BRT systems can easily be customized to community needs and incorporate state-of-the-art, low-cost technologies that result in more passengers and less congestion. 51

Complete Streets. Streets designed and operated to enable safe access and mobility for transportation system users of all ages and abilities, including pedestrians, bicyclists, motorists, and public transportation users.

Congestion Management Process (CMP). A CMP is a systematic and regionally-accepted approach for managing congestion that provides accurate, up-to-date information on transportation system performance and assesses alternative strategies for congestion management that meet state and local needs. The CMP is intended to move these congestion management strategies into the funding and implementation stages.52

Congestion Pricing. Sometimes called "value pricing," congestion pricing is a way of harnessing the power of the market to reduce traffic congestion. Congestion pricing works by shifting purely discretionary rush hour highway travel to other transportation modes or to off-peak periods. By removing even a fraction of the vehicles from a congested roadway, pricing enables the system to flow more efficiently, allowing more vehicles to move through the same physical space.53

Connectivity Index. A Connectivity Index can be used to quantify how well a roadway network connects destinations. Indices can be measured separately for motorized and nonmotorized travel, taking into account nonmotorized shortcuts, such as paths that connect cul-de-sacs, and barriers such highways and roads that lack sidewalks.54

Context Sensitive Roadway Design. This form of design promotes a collaborative, multidisciplinary process that involves all stakeholders in planning and designing transportation facilities that meet the needs of users and stakeholders. Context sensitive roadway designs are compatible with their setting and preserve scenic, aesthetic, historic and environmental resources; respect design objectives for safety, efficiency, multimodal mobility, capacity and maintenance; and integrate community objectives and values relating to compatibility, livability, sense of place, urban design, cost and environmental impacts.55

Green Infrastructure. Green infrastructure is strategically planned and managed networks of natural lands, working landscapes and other open spaces that conserve ecosystem values and functions and provide associated benefits to human populations.56 One common use in transportation of green infrastructure is as an approach to wet weather management that is cost-effective, sustainable, and environmentally friendly. Green infrastructure water management approaches and technologies infiltrate, evapotranspire, capture and reuse storm water to maintain or restore natural hydrologies.57

Greenhouse Gas (GHG) Emissions. Gases that trap heat in the atmosphere are often called greenhouse gases.58 Many chemical compounds found in the Earth's atmosphere act as "greenhouse gases," including some that occur in nature (water vapor, carbon dioxide, methane, and nitrous oxide) and others are exclusively human-made (like gases used in refrigerants).59

High Occupancy Toll (HOT) lanes. HOT lanes are limited-access, normally barrier separated highway lanes that provide free or reduced cost access to qualifying HOVs, and also provide access to other paying vehicles not meeting passenger occupancy requirements.60

Intelligent Transportation Systems (ITS). The application of advanced technologies to improve the efficiency and safety of transportation systems.61

Intermodal. The ability to connect, and the connections between, modes of transportation.62

Livability. Using the quality, location, and type of transportation facilities and services available to help achieve broader community goals. Livability in transportation helps to achieve those goals by leveraging financial resources and using the transportation planning process to advance supportive projects, policies, or decisions. Livability directly benefits people who live in, work in, or visit an area – whether in an urban, suburban, or rural context.

Managed Lanes. Transportation facilities or a set of lanes where operational strategies are proactively implemented and managed in response to changing conditions. Examples of managed lane projects include HOV lanes, HOT lanes, value priced lanes, or exclusive or special use lanes.63

Management and Operations (M&O). See transportation systems management and operations.

Metropolitan planning organization (MPO). A metropolitan planning organization (MPO) is defined in Federal Transportation Legislation (23 USC 134(b) and 49 USC 5303(c)) as the designated local decisionmaking body that is responsible for carrying out the metropolitan transportation planning process. An MPO must be designated for each urban area with a population of more than 50,000 people (i.e., for each Urbanized Area (UZA) defined in the most recent decennial Census).64

Mode Share. The percentage share that a particular type of transportation mode (i.e., car, bus, rail, plane, etc.) has in relation to other modes.65

Parking Management. Parking management includes a variety of strategies that encourage more efficient use of existing parking facilities, improve the quality of service provided to parking facility users and improve parking facility design.66

Placemaking. Placemaking is a multi-faceted approach to the planning, design and management of public spaces. Put simply, it involves looking at, listening to, and asking questions of the people who live, work and play in a particular space, to discover their needs and aspirations. This information is then used to create a common vision for that place. The vision can evolve quickly into an implementation strategy.67

Quiet Pavements. Innovative pavement technologies that result in substantial reductions in tire/pavement noise.68

Reliability. Refers to the degree of certainty and predictability in travel times on the transportation system. Reliable transportation systems offer some assurance of attaining a given destination within a reasonable range of an expected time. An unreliable transportation system is subject to unexpected delays, increasing costs for system users.69

Road Diets. Entails removing travel lanes from a roadway and utilizing the space for other uses and travel modes.70

Road pricing. Road pricing refers to a fee related to the use of a roadway facility. Road pricing may impose a price on a vehicle's use of the road based on time of day, location, type of vehicle, number of occupants, or other factors.71

Sprawl. Urban form that connotatively depicts the movement of people from the central city to the suburbs. Concerns associated with sprawl include loss of farmland and open space due to low-density land development, increased public service costs, and environmental degradation as well as other concerns associated with transportation.72

Sustainability. Meeting the needs of the present without compromising the ability of future generations to meet their own needs.73 Sustainability incorporates the 'triple bottom line' concept, which includes giving consideration to three primary principles: equity (also known as social or people), ecology (also known as environment), and economy (also known as the bottom line or cost component). The goal of sustainability is "the satisfaction of basic social and economic needs, both present and future and, the responsible use of natural resources, all while maintaining or improving the well-being of the environment and ecology on which life depends."74

Traffic Calming. The combination of mainly physical measures that reduce the negative effects of motor vehicle use, alter driver behavior and improve conditions for non-motorized street users.75 Transportation systems management and operations (M&O). An integrated program to optimize the performance of existing infrastructure through the implementation of systems, services, and projects designed to preserve capacity and improve security, safety, and reliability of the transportation system.76

Travel Time Index. The travel time index is a measure of average conditions that tells one how much longer, on average, travel times are during congestion compared to during light traffic.77

47 Levinson, D. M. and E. Istrate, Access for Value: Financing Transportation Through Land Value Capture, The Brookings Institute, 2011. Available at: [ Return to note 47 ]

48 Centers for Disease Control and Prevention (CDC), CDC Transportation Recommendations, April 2010. Available at: [ Return to note 48 ]

49 U.S. EPA, Brownfields and Land Revitalization, November 2009. Available at: [ Return to note 49 ]

50 Clean Ohio Fund, "Brownfield Revitalization." Available at: [ Return to note 50 ]

51 National BRT Institute, What is BRT?, 2009. Available at: [ Return to note 51 ]

52 U.S. DOT, FHWA, Congestion Management Process: A Guidebook, April 2011. Available at: [ Return to note 52 ]

53 U.S. DOT, FHWA, Congestion Pricing, A Primer, December 2006. Available at: [ Return to note 53 ]

54 Victoria Transport Policy Institute, Roadway Connectivity, March 2011. Available at: [ Return to note 54 ]

55 Institute of Transportation Engineers (ITE), Designing Walkable Urban Thoroughfares: A Context Sensitive Approach: An ITE Recommended Practice, 2010. Available at: [ Return to note 55 ]

56 The Conservation Fund, "What Is Green Infrastructure?" Available at:[ Return to note 56 ]

57 U.S. EPA, Managing Wet Weather with Green Infrastructure, January 2011. Available at: [ Return to note 57 ]

58 U.S. EPA, "Greenhouse Gas Emissions," April 2011. Available at: [ Return to note 58 ]

59 U.S. Department of Energy, Energy Information Administration, "What Are Greenhouse Gases?," April 2004. Available at: [ Return to note 59 ]

60 U.S. DOT, FHWA, A Guide for HOT Lane Development, March 2003. Available at: [ Return to note 60 ]

61 U.S. DOT, FHWA, Planning Glossary. Available at: [ Return to note 61 ]

62 U.S. DOT, FHWA, Planning Glossary. Available at: [ Return to note 62 ]

63 U.S. DOT, FHWA, Managed Lanes: A Primer, August 2008. Available at: [ Return to note 63 ]

64 U.S. DOT, FHWA, Census Issues: Frequently Asked Questions, March 2003. Available at:[ Return to note 64 ]

65 Caltrans, "Glossary," California Transit-Oriented Development, 2000. Available at: [ Return to note 65 ]

66 Victoria Transport Policy Institute, The TDM Encyclopedia, June 2011. Available at: [ Return to note 66 ]

67 Project on Public Spaces, "What is Placemaking?" Available at: [ Return to note 67 ]

68 U.S. DOT, FHWA, Quiet Pavement Systems in Europe, FHWA International Technology Exchange Program, April 2005. [ Return to note 68 ]

69 U.S. DOT, FHWA, Planning Glossary. Available at: [ Return to note 69 ]

70 Institute of Transportation Engineers, Road Diet Handbook, 2004. Available at: [ Return to note 70 ]

71 U.S. DOT, FHWA, Road Pricing Defined. Available at: [ Return to note 71 ]

72 U.S. DOT, FHWA, Planning Glossary. Available at: [ Return to note 72 ]

73 World Commission on Environment and Development, "Towards Sustainable Development," in Our Common Future, 1987. Available at: [ Return to note 73 ]

74 U.S. DOT, FHWA, "What is Sustainability?" in Sustainable Highways Evaluation Tool, August 2006. Available at: [ Return to note 74 ]

75 Lockwood, Ian, "ITE Traffic Calming Definition," ITE Journal, July 1997, pg. 22. [ Return to note 75 ]

76 Transportation Research Board, Glossary of Regional Transportation Systems Management and Operations Terms, Transportation Research Circular, E-C133, April 2009. Available at: [ Return to note 76 ]

77 U.S. DOT, FHWA, Travel Time Reliability: Making it there on Time, All the Time, January 2006. Available at: [ Return to note 77 ]

previous | Table of Contents