Characteristics of Transit Supportive Places
Transit supportive places are locations where the presence of effective and predictable transit can be enhanced through appropriate patterns and types of development. Research has shown that the presence or absence of certain physical design features, transit characteristics, and other supportive polices that promote a diversity of land uses, compact design, greater transportation mode choice, and safe and walkable streets can reduce driving and increase transit ridership, walking, and biking (Cervero and Ewing, 2010; Rajamani, et. al. 2013; Niemeier, Bai, and Handy, 2011). Early research identified three “Ds” (density, diversity and design) as essential elements of transit supportive development (Cervero and Kockelman, 1997). Further analytical research revealed other common elements, including destination accessibility, distance to transit, demographics, and demand management.
Based on an analysis of the literature, 10 characteristics or elements were identified that are considered to be best practices that promote the creation of transit supportive places. These best practices form the organizational structure for the tools that will be used in the Transit Supportive Planning Toolkit. It is important to note that these practices need to be used together in varying degrees to achieve development patterns and transportation systems that create livable places while also increasing transit ridership and reducing GHG emissions.
Each of the 10 characteristics described below has a linked page, which lists potential strategies for implementation, and delves into the potential effectiveness of each strategy to reduce VMT, lower greenhouse gas emissions, and support transit ridership. The metric that is used to evaluate the relative effectiveness of an individual element is “elasticity.” Elasticity measures the percentage change in the dependent variable, such as walking or transit use, in response to a 1% change in an independent variable, such as transit service, land use density, or land use mix. A positive elasticity indicates the effect is the same as the cause. For example, a 0.07 elasticity for walking with respect to land use density means that each 1% increase in density causes walking to increase 0.07%.
Best Practice Characteristics
Compact design, or density, refers to the number of people, homes, or jobs per unit of area. Higher density, especially within a quarter or half mile of a transit facility, can impact travel behavior by providing more opportunities to live in close proximity to transit. These residents have improved mobility choices, and if mixed-use is combined with greater density, they also benefit from reduced travel distances for daily activities and decreased reliance on the automobile. Compact design is also associated with other common characteristics of transit supportive development, including regional accessibility, land use mix, and more transportation options.
Complete neighborhoods refer to places where people have safe and convenient access to goods and services. Complete neighborhoods include a variety of housing options, retail and commercial services, and community services. Complete neighborhoods bring land uses and amenities closer together, reduce travel distances, and allow for more non-automobile trips. As with Compact Development, the common practice is that the greatest area of impact for Complete Neighborhoods is within a half mile of fixed guideway transit facilities, such as rail, and a quarter mile of major bus facilities.
Well-connected streets and non-automobile networks bring destinations closer together, reduce travel distances, and improve pedestrian and bicycle access to adjacent areas and uses. Poorly connected street and non-automobile networks with cul-de-sacs, frequent dead ends, and difficult-to-cross streets provide less accessibility than a well-connected network. Street connectivity is measured by the number of intersections per square mile, portion of four-way stops, percentage of cul-de-sacs, path directness, or road density, among other measures.
Placing buildings towards the edges of streets and public spaces helps to create walkable urban environments. Buildings placed near the edge of sidewalks help provide a sense of definition to streets and also emphasize the pedestrian access compared to locations where parking is located between the sidewalk and the building. Placing buildings behind parking lots isolates pedestrians from activities and uses, requires them to walk greater distances, and exposes them to more vehicular traffic. Curb-cuts, driveways, and service entrances and load areas further disrupt pedestrian access.
Low-income residents, including seniors, often have some of the lowest rates of car ownership and highest rates of transit ridership. Adding new affordable housing near transit can improve access to employment, health care, and education opportunities and reduce commuting cost for low-income families, while creating a more efficient transit system. Housing is considered affordable when it costs no more than 30% of the monthly household income. Designated affordable housing generally serves households earning less than 60% of the area median income. If economic conditions are right, transit investment may increase property values around the stations, which in turn creates a need to preserve existing affordable housing near transit. Challenges may include pressure to convert affordable units to market rate, loss of housing stock, and population displacement.
Increased property values near transit stations may put cost pressures on existing businesses by attracting new retailers and jobs that compete with existing neighborhood businesses. Commercial stabilization measures can help protect and encourage existing small, local businesses that serve the needs of neighborhood residents. These businesses may benefit from an increase in pedestrian activity and transit riders, while providing the goods and services needed by riders and reducing the need for additional auto trips.
Prioritizing transit and active transportation as the first and highest priority of a circulation network may result in increased transit service, through better travel times and speeds, which can result in significant transit ridership improvements. Transit-first policies prioritize transit and non-motorized transportation modes and can be used to support decision-making related to sustainable transportation. Policies can be used during development review, allocation of right-of-way, and planning and design efforts to ensure the expedited movement of transit vehicles and to improve the safety of pedestrians and cyclists accessing transit stops. Transit accessibility refers to the ease of accessing that service by vehicle, walking, biking, or transit. Accessibility is a measure that considers both transportation and land use.
Improving transit station and stop design can increase the comfort, convenience, and attractiveness of transit, supporting TOD and increasing transit ridership. On average, transit riders spend 10% - 30% of the trip waiting for transit vehicles. Many transit riders are sensitive to the conditions where they wait, encouraging or discouraging ridership based on station conditions. Offering amenities and services, and providing a clean and safe environment, makes riding transit more convenient.
Parking management affects the relative supply, price, and regulation of parking facilities within an area. Efficient parking management can reduce the parking supply needed, allowing an increase in land use intensity, mix of uses, wider sidewalks, and bike networks. Parking management strategies may also reduce vehicle ownership and use.
Transportation Demand Management (TDM) refers to various strategies aimed at more efficient use of transportation systems. TDM strategies influence a variety of factors to encourage greater transportation system efficiency, including trip mode, trip timing, travel safety, and trip cost. Benefits of TDM include reduction in road and parking congestion, pollution reduction, increase in transit ridership, and more efficient land use.
Quality of pedestrian and bicycle circulation conditions affect travel activity including transit ridership. Adding pedestrian and bicycle amenities to station areas and connecting those facilities to the surrounding area can create a more accessible transit environment, encouraging new riders.