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OCR for page 55
55 The conservative approach involves modifications to the exist- Infrared technology in a suburban area west of Portland--on ing priority system such as increasing the frequency of prior- Tualatin Valley Highway, TriMet was ready to proceed with ity calls, allowing any bus to obtain priority regardless of the a wider scale application of this technology. number of passengers on board or its on-time performance, and longer green extension/red truncation green phase alloca- At the same time, the city of Portland was interested in tions to bus operations. The advanced approach would take applying the Optical Infrared technology for emergency the necessary steps to ensure that a bus clears an intersection vehicle preemption on a portion of its signal system, and hence without stopping, similar to the full priority operation used for TriMet and the city cooperated on submitting a grant appli- light rail. cation for $4.5 million to obtain Congestion Mitigation and Air Quality (CMAQ) funding to develop a combined transit From a technology perspective, Metro is proceeding with priority/emergency vehicle preemption system in the city. This an on-board systems integration project that will include wire- was known as the "Streamline" program. The intended goal of less communications to the TSP equipment in the signal equip- the program for TriMet was to recoup its investment through ment, as opposed to the original radio frequency tag/wayside running time saved by "streamlining"--in other words, if four reader technology. This system has been estimated to save or five buses could be saved during peak period operation, the 70% of the cost of installing TSP per intersection. Using this bus operating cost savings would offset the investment in tran- new system, TSP is scheduled to be installed at 120 intersections sit preferential treatments paid for through TriMet's contribu- in the five Rapid Ride corridors. tions to the program. To date, signal priority has been installed at 275 intersections using the Opticom Infrared technology. PORTLAND, OREGON Since the opening of the first LRT line in 1986, two addi- tional lines have been developed with extensive street- TriMet, the public transit agency in the Portland, Oregon, area, running operation: (1) the Westside line (opened in 1998), includes bus, light rail, and streetcar operations. It has been which operates on-street using Morrison/Yamhill Streets, implementing transit priority treatments on the street system in 18th Avenue, and SW Jefferson Street on the west side of its region since the late 1970s, primarily in the city of Portland. downtown, and along Washington Street through central Hillsboro (now connected with the Eastside line to form the History Blue Line), and (2) the Yellow Line (opened in 2004), which operates much of its route along North Interstate Avenue in Transit priority treatments in Portland started with the 5th and a median transitway through north Portland. 6th Avenue bus malls in 1976. These streets were primarily used by local and express buses, with general traffic sharing In 2001, the Portland Streetcar line opened, operating the street, in certain blocks in their own lanes (primarily for along 10th and 11th Avenues though downtown Portland and hotel and parking garage access). This was followed by the along Lovejoy and Northrup Streets in northwest Portland-- implementation of median bus lanes on Barbur Boulevard sharing the right through lane on these streets with general south of downtown Portland in 1978 (these lanes were discon- traffic. In September 2009, the original bus malls along 5th tinued in 1984 owing to some intersection crash experience). and 6th Avenues were reopened to include LRT vehicles and In 1985, Portland's first light rail line opened between down- general traffic along their entire length, along with bus traffic. town and Gresham, with the line downtown operating in on- street dedicated lanes next to general traffic (on Morrison and Impacts of the Streamline Program Yamhill Streets), and a median transitway configuration along East Burnside Street east of I-205. The Streamline program was applied to 12 of the more heav- In 1992, TriMet received a grant from the FTA to develop ily used routes in TriMet's bus system. In an evaluation of on-street priority and stop improvements and initiated a Transit the effectiveness of the program, four specific measures were Streets Program in the city of Portland. This program was ori- identified through "before" and "after" assessments of each ented to bus stop improvements (new or improved passenger route: ridership changes, additional fare revenue, on-time waiting areas, curb ramps, shelter pads), but did include some performance, and roundtrip time savings. The following is a intersection priority treatments such as bus bypass lanes, stop summary of streamlining impacts that have been identified to relocation, and special signal phasing. date, from a 2007 report: In 1994, TriMet ventured into bus signal priority develop- 1. The time savings resulting from streamlining has not ment. It started with a test of two alternate bus detection tech- allowed any permanent reduction in the number of peak nologies on Powell Boulevard (LoopComm--an inductive buses on a route--therefore, no short-term operations loop/transponder system and TOTE--a radio frequency tag/ savings. wayside reader system). This was followed by a test of the 2. The 12 streamlined routes, on average, operate a round Optical Infrared bus detection technology on Multnomah trip 0.8 s faster than during the weekday a.m. peak period Boulevard in 1995. After further testing of the Optical in 2000. In comparison, seven non-streamlined routes in