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56 the city of Portland were identified as having a round-trip 16th Street Transit Mall travel time 1.3 s slower than in 2000, and four suburban Skip-stop operation on 15th and 17th Streets routes were shown to operate 2.3 s slower than in 2000. Broadway/Lincoln bus lanes 3. The running time savings that have been achieved Limited Stop Service on East Colfax Avenue. through streamlining have delayed adding buses to streamlined routes by an estimated eight years. An Each of these projects has had a significant impact on pro- annual $140,000 operating cost per saved bus, multi- viding travel time improvements to and through the down- plied by 12 routes over eight years, results in $13.4 mil- town Denver area. A further description of each project, how lion in long-term savings. The value of delaying the it developed, and its current impact are described here. purchase of 12 additional buses for eight years is an added capital cost savings. 4. The combination of focusing service increases on fre- 16th Street Mall quent service routes, accompanied by streamlining and The 16th Street mall was a project completed in 1982 that marketing efforts, has resulted in 12,000 more week- provided new low-floor, electric bus service connecting two day bus boardings than would have occurred if service new transit centers at the east and west ends of downtown; change resources were spread systemwide. These added at Blake Street and the Civic Center. The transit mall was passengers result in added fare box revenue of approx- developed as a complete rebuild of 16th Street, with granite imately $1.7 million annually. pavers and expanded sidewalks. The mall was developed with no lanes for general traffic, with emergency vehicles Figure 42 shows TriMet's current bus signal priority sys- allowed to use the transit lanes when needed. tem as it is relates to its four proposed BRT routes and the rest of the transit system. A key element of the 16th Street shuttle operation is a TSP system that enables shuttle buses to navigate the length DENVER, COLORADO of the mall with a highly reliable signal progression system. The city/county of Denver traffic engineering staff, in con- The Regional Transportation District (RTD) in Denver has junction with RTD staff, developed a "single alternate pro- been involved in transit priority development on its urban gression" system based on a 75-s downtown traffic signal streets since the early 1980s. Four substantial transit service and cycle length. It provides a green signal at each intersection facility improvements were implemented in the 19811984 time along the mall after a shuttle bus has traversed a block, made frame: a near-side stop to board and deboard passengers, and is ready FIGURE 42 TriMet TSP locations (Source: TriMet).

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57 to proceed to the next bus stop. Vehicle bus dwell times are highly consistent, between 12 and 15 s for normal board- ing conditions. Any bus bunching resulting from wheelchair boardings or other anomalies is handled by variation in recov- ery time at one of the transit centers at the end of the mall. Another priority measure is the starting signal used at each transit center. The signal aspects display both the num- ber of traffic signal cycles since the last shuttle departure (multiples of 75 s) and a diagonal bar "proceed with caution" aspect that assures the bus operator they will have a green signal indication at the next intersection. 15th/17th Street Skip-Stop Operation FIGURE 43 Overhead signal and signage--Broadway Bus Lane--Denver (Source: Denver Regional Transportation District). Associated with the development of the 16th Street Mall, the bus lanes on these two one-way streets were replaced with an "XYZ skip-stop pattern" in 1981. The stop pattern involves East Colfax Avenue Limited Stop Service three groups of buses stopping every third block, with three buses per stop. There is one stop common to all buses. The spe- In 1985, the RTD implemented one of the first BRT-type cific stop pattern for 17th Street was previously shown in chap- services in the United States, along East Colfax Avenue ter two. A total of 15 bus routes use this stop pattern on both between Fitzsimmons Medical Center and downtown Den- 15th and 17th Streets. The basic bus operation is as follows: ver. This service focused on the introduction of limited-stop bus service in the corridor, with enhanced bus stops at certain 1. Buses leaving stop pick up the green traffic signal pro- locations including greater shelter and other passenger ameni- gression band. ties. At the time of this service implementation, TSP strategies 2. Next passenger stop is made during the red signal were still not fully developed, and hence the RTD undertook phase. Buses load and unload passengers, then proceed extensive bus travel time and delay studies to determine on next green wave. where stops might be consolidated and moved to reduce bus travel time in the corridor. The three-block travel, and the increase in general traffic speed (by an average of 12.5 mph), are major factors in improved travel times. Also, with the spreading of stops, side- Existing Light Rail Lines walk crowding at bus stops decreased 40% to 50%. The more organized bus operation also resulted in a 25% to 40% increase The Denver RTD to date has implemented three light rail in the speed of general traffic on 15th and 17th Streets. lines: (1) the Southwest Line from downtown to Mineral Avenue, (2) the Southeast Line from downtown to the Den- ver Tech Center, and (3) the Central Line to Union Station. Broadway/Lincoln Bus Lanes The Southwest and Southeast lines operate at-grade on Stout and California Avenues in downtown in contraflow opera- Bus lanes on Broadway and Lincoln Streets, a major north tion on the right side of each street either next to the curb or south one-way pair between I-25 and downtown Denver, parking lane (see Figure 6). were initiated in 1976. The bus lanes, each 4 miles in length, were found to provide an average travel time savings of 5 min per bus during the peak period (0.8 min per mile). Current FasTracks and FastConnects Programs The bus lanes operate as exclusive transit lanes from 6 to 10 a.m. in the morning and from 3 to 7 p.m. in the afternoon Since 2000, the RTD has embarked on a program, called Fas- on weekdays. Tracks, to develop more than 150 miles of new rapid transit corridors in the Denver region, including BRT operating on- The initial passive bus lane signs were replaced by current street in certain corridors. Associated with FasTracks is a pro- bus lane signs with flashing yellow lights marking the times gram called FastConnects, which addresses strategies to facil- when the bus lanes are in operation, thus better alerting adja- itate passenger transfers between major routes (see Figure 44). cent general motorists (see Figure 43). There is a single bus These programs have as their core a program of transit prior- queue jump traffic signal on northbound Lincoln at 13th ity treatments. Transit priority strategy investments are being Avenue to facilitate left turns by all buses at Colfax Avenue identified based on cost-effectiveness--specifically relat- into the Civic Center station. ing ridership to capital and operating costs. The investment

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58 FIGURE 44 Denver RTD FastConnects system (Source: Denver Regional Transportation District).

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59 strategy that has been developed focuses on the following Transit Signal Priority Study Project. The scope of the project activities: included goals and objectives setting, system inventory and evaluation, technology review, technology strategy selection, 1. Measuring and comparing average bus versus gen- and implementation sites selection and functional design. eral traffic performance for selected links in different corridors. As part of the study, five corridors were chosen as test bed 2. Identifying potential locations to implement travel TSP corridors and simulated and analyzed under both exist- time improvement measures. ing traffic conditions and a "with TSP" scenario to determine 3. Identifying facilities, priorities, or other measures that the effect that the addition of TSP would have on both buses may improve bus travel time, by how much and the and general traffic. Findings were summarized in four cate- extent of riders affected. gories: (1) TSP Corridor Findings, (2) TSP Intersection Find- 4. Developing specifications for the identified improve- ings, (3) TSP Transit Route Findings, and (4) Corridor-Specific ments to estimate annualized capital and operating costs Findings. Key general findings were as follows: and savings. 5. Selecting projects for implementation based on fund- Larger TSP benefits to transit vehicles can be achieved ing and other relevant system-wide considerations. on corridors with regularly spaced signalized intersec- tions that have good progression or the potential for Measures of effectiveness that are being used in different good progression. corridor evaluations include: TSP is best applied to a long series of signalized inter- sections along a single travel corridor. Effects on Transit: vehicle travel time, vehicle on-time TSP study intersections with major street crossings and performance; and Effects on Traffic: vehicle-hours of delay, person-hours heavy side-street vehicle demand are more negatively of delay, vehicle travel time, vehicle travel speed, travel affected with TSP calls. time variability, and level of service. Intersections near or at capacity are more negatively affected by TSP than other intersections. Coordination among different affected organizations in Transit routes with less frequent stops and travel along implementing transit priority treatments is being addressed one street corridor realize more travel time benefits with through a work group of the regional Metropolitan Planning TSP. Organization, the Denver Regional Council of Governments Near-side bus stops limit the distance between the TSP (DRCOG). In addition, ad hoc work groups have been estab- check-in detector and the intersection from the recom- lished specific to certain projects. mended 500 ft, reducing the effectiveness of TSP. Denver Regional Transit Signal Priority Project Based on the results of the simulation results and discus- sions of the findings with DRCOG, RTD, the city/county of Since 1989, the DRCOG has been working with the Colorado Denver, and the city of Boulder, specific recommendations to DOT and local governments to coordinate and improve tim- institute TSP were made for the South Broadway, Colfax ing of the traffic signals on major streets in the region. In 2005, Avenue, Colorado Boulevard, and Lincoln Street corridors in DRCOG and RTD entered into an agreement to conduct a Denver, and the HOP corridor in Boulder.