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146 APPENDIX E Glossary of Terms Multimodal Facilities: The combination of physical facil- Transit Mode Terminology: ities for highways, public transit, pedestrians and bicycles. Local Bus: The most common form of public transit in the (Multimodal Facilities = Highways + Transit + Pedestrians + United States, it is distinguished by single bus vehicles op- Bicycles). erating with a capacity of 35 to 50 seated passengers, oper- Corridor: The combination of multimodal facilities and ated along fixed routes, running in mixed-flow traffic along the land uses surrounding them. (Corridor = Multimodal surface streets. Since they run in mixed traffic, buses are typ- Facilities + Surrounding Land Uses). The interaction of multi- ically slower than other forms of transit, and because they modal facilities and land uses can take many forms, but can follow fixed routes with frequent stops, they typically travel generally be described as ranging from auto-oriented to transit- at slower speeds than auto traffic in the same corridor. oriented corridors. These two polarities are described in greater Express/Rapid Bus: Generally distinguished from local bus detail below. service by the limited number of stops made along a fixed route. The route can be in a surface street in mixed-flow Multimodal Corridor "New Paradigm": Optimized com- traffic lanes either on a local surface street or a freeway. binations of multimodal facilities and land uses. Fewer stops mean fewer opportunities to attract passen- Physical Context: Refers to the characteristics of the land gers, so this mode is best suited to serve a large destination use, urban design (street and block characteristics), social, such as a central business district paired with either a sys- economic, demographic, and so on surrounding the existing tem of widely spaced intermodal transfer stations (for ex- or future transportation facilities. ample, park-and-ride lots surrounding stations) or dense residential clusters. Also called rapid or transit-priority Institutional Context: Refers to the institutional arrange- buses, express buses can be fitted with signal priority tech- ments for physical design, highway operations, other modal nology to increase running speeds. Other route improve- operations, and land development decisions along and near the ments include queue jump lanes, bus stop "bulb-outs," and corridor. This also includes institutional arrangements for pro- exclusive bus lanes. These improvements are also associ- viding access to the corridor from the area served by the corri- ated with BRT (see description below), but unless most or dor as well as the policies, regulations, and other transportation all of these elements are in place and in use, the route is gen- management actions that help determine corridor operations. erally considered express or rapid bus, not a full BRT sys- Intermodal Facilities/Station: A station or node where tem. Express bus service with park-and-ride lots around transfers between travel modes are facilitated. their stations can serve at relatively low corridor residential densities of four dwelling units per acre and CBDs as small System Access: Refers to the characteristics of how the trans- as 20 million square feet because this configuration draws portation facility is accessed, including transit stations, bus on a large commuter shed. Pedestrian access stations re- stops, on- and off-ramps-and so on quire higher corridor residential densities of 15 dwelling Central Business District (CBD): The CBD is the central units per acre or more and a CBD of at least 50 million district of a city, usually typified by a concentration of retail square feet.2 Express buses are also very flexible. An express and commercial buildings.1 2Pushkarev, B. & J. Zupan, Public Transportation and Land Use Policy. Indiana 1 University Press, Bloomington, IN, 1977. p. 187.

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147 bus--such as AC Transit's Transbay routes from the East be financially feasible. Minimum corridor residential den- Bay to downtown San Francisco--can run as a local service sities for LRT range from 9 to 12 dwelling units per acre.2 in a collector mode, then as an express bus to the destination. Heavy Rail/Rapid Transit (HRT): Heavy rail transit pro- Bus Rapid Transit (BRT): The most important feature of vides intraurban service running on exclusive, dedicated, BRT is that it runs on a dedicated, exclusive lane of travel, fully grade-separated rights-of-way. Called "heavy" because giving it a high level of service reliability (since it does not of its large passenger capacity, HRT can generally carry compete for right-of-way with other modes) and speed. up to 400 passengers per track per hour at high speeds and Bus priority technologies (such as signal prioritization) are excellent service reliability. Cars are generally designed to often used to improve travel times and provide a competi- carry 90 to 150 people each in comfort, and up to double tive edge to BRT vis--vis other modes. Off-bus fare collec- that in "crush load" conditions. The trains are typically very tions as well as platform boarding and alighting are fre- long compared to LRT, up to 8 to 11 cars depending on quently used to reduce dwell times at stops.2 In addition to their size. To reduce dwell times and increase service speeds, operational improvements, the cost of a BRT system can be HRT systems have fare collections in the stations, as well as about one-third that of a light rail system.3 This makes BRT high-level station platforms and more doors per car than feasible for somewhat less dense and smaller CBD corridors other vehicles to speed boarding and alighting.2 Express than more capital-intensive rail systems. As a rule of thumb, HRT service is sometimes provided via additional, parallel minimum CBD size for a BRT system to generate adequate tracks to allow skip-stop trains.7 HRT is generally thought ridership is around 25 million square feet.4 to be financially infeasible for corridors with CBDs less than Light Rail Transit (LRT): Light rail vehicles run singly or in 50 million square feet and corridor residential densities less short trains on tracks in a variety of right-of-way environ- than 12 dwelling units per acre.2 ments, including mixed-flow surface streets, dedicated Commuter Rail: Commuter rail provides service between lanes with grade crossings, and fully grade-separated dedi- a metropolitan area's suburban areas and its main CBD. It cated facilities.2 Compared to BRT, LRT offers and requires usually shares tracks with other railroad traffic (freight and more fixed capital investments and, as such, is thought to intercity passenger) and so can suffer from delays due to be more attractive to riders and developers.5 Another ad- these competing uses. Usually, its power source is on-vehicle vantage of LRT, particularly in comparison to heavy or (locomotive) versus off-track (for example, overhead wires commuter rail, is its operating flexibility. LRT can operate and middle third rail). Commuter rail almost always runs in mixed traffic and exclusive rights-of-way conditions, all at grade since locomotives are too heavy for aerial or along the same line.2 This is important because many free- subways, and they typically have stub-end stations at the way right-of-ways do not penetrate downtown areas, and periphery of downtowns. Suburban stations almost always LRT can do so on city streets at a relatively low cost com- have surface parking. Typically, commuter trains run less pared to heavy or commuter rail (see below).6 Therefore, frequently than other forms of rail transit, often only dur- for multimodal corridors where transit is being retrofitted ing peak periods. In this way, they tend to cater to "choice" into an existing freeway right-of-way, the freeway need not riders who prefer public transport because of speed, relia- run directly to the activity center that the transit system will bility, and avoidance of traffic congestion and parking serve. Rather, the LRT system can take advantage of the op- problems. To compete with auto traffic travel times, com- portunities for colocating its tracks along an available free- muter trains are often scheduled to skip stops, resulting in way right-of-way for most of the route, then veer away to express and local services in the same corridor. Compared run on surface streets to reach the CBD. Minimum CBD to intercity rail service, commuter rail has more frequent size for an LRT system is around 35 million square feet, but stops and seating densities. This requires train equipment for lines that can be built along existing rights-of-way (such with high acceleration and deceleration as well as seating as a freeway), CBDs as small as 20 million square feet may and door configurations that allow rapid loading and un- loading. In these ways, commuter rail equipment and sys- tem design are comparable to HRT or LRT, but the route distances are often longer, ranging between 15 and 30 miles. 3Leal, Monica T. & Robert L. Bertini, Bus Rapid Transit: An Alternative For De- Because of these design features, there are few commuter veloping Countries, 4TCRP Report 90, Volume 2, page 2-4. 5Diaz, Roderick B., Impacts Of Rail Transit On Property Values. http://www. 6Examples of LRT systems traveling on city streets through central business dis- 7Examples of HRT systems providing express service include Chicago, New York tricts include Boston, Edmonton, Philadelphia, Pittsburgh and San Jose. City, and Philadelphia.

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148 rail station area TODs. Where development densities pro- rail is generally thought to be financially infeasible for cor- vide an adequate ridership market, commuter lines are ridors with CBDs less than 50 million square feet. The electrified and the stations have platforms and automatic CBD should have a pre-existing rail line serving it, and the doors. Where corridor market densities are lower, slower service corridor residential densities should be no less than speeds are acceptable and diesel-pulled trains with low- 1 to 2 dwelling units per acre2 with good transit and auto level station platforms are frequently used.2 Commuter feeder access to corridor stations.