National Academies Press: OpenBook

Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH (2012)

Chapter: Chapter 2: Identification of Participating LRT Agency and Potential Study Crossings

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Suggested Citation:"Chapter 2: Identification of Participating LRT Agency and Potential Study Crossings." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
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Suggested Citation:"Chapter 2: Identification of Participating LRT Agency and Potential Study Crossings." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
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Suggested Citation:"Chapter 2: Identification of Participating LRT Agency and Potential Study Crossings." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
×
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Suggested Citation:"Chapter 2: Identification of Participating LRT Agency and Potential Study Crossings." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
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Suggested Citation:"Chapter 2: Identification of Participating LRT Agency and Potential Study Crossings." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
×
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Suggested Citation:"Chapter 2: Identification of Participating LRT Agency and Potential Study Crossings." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
×
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Suggested Citation:"Chapter 2: Identification of Participating LRT Agency and Potential Study Crossings." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
×
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Suggested Citation:"Chapter 2: Identification of Participating LRT Agency and Potential Study Crossings." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
×
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Suggested Citation:"Chapter 2: Identification of Participating LRT Agency and Potential Study Crossings." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
×
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Suggested Citation:"Chapter 2: Identification of Participating LRT Agency and Potential Study Crossings." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
×
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Suggested Citation:"Chapter 2: Identification of Participating LRT Agency and Potential Study Crossings." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
×
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Suggested Citation:"Chapter 2: Identification of Participating LRT Agency and Potential Study Crossings." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
×
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Suggested Citation:"Chapter 2: Identification of Participating LRT Agency and Potential Study Crossings." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
×
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Suggested Citation:"Chapter 2: Identification of Participating LRT Agency and Potential Study Crossings." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
×
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Suggested Citation:"Chapter 2: Identification of Participating LRT Agency and Potential Study Crossings." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
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TCRP Web-Only Document 53 3 CHAPTER 2: IDENTIFICATION OF PARTICIPATING LRT AGENCY AND POTENTIAL STUDY CROSSINGS This chapter summarizes the approach used for identifying both the participating LRT agency as well as the potential study crossings. The objectives of Task 1 were to survey LRT agencies and to identify potential highway-rail crossings suitable for further study. Task 1 was composed of the following two subtasks:  Task 1-1: Identify, select, and survey LRT agencies in North America that are candidates for LRV operation speeds exceeding 35 mph; and  Task 1-2: Identify potential crossings suitable for further study. Figure 1 illustrates the flow of the Task 1 subtasks, as well as the Task 1 output that will feed into Task 2. The findings from both of the Task 1 subtasks are discussed in more detail below. Figure 1. Subtask Flow Diagram for Task 1 Each of these subtasks is described in more detail below. IDENTIFY, SELECT, AND SURVEY LRT AGENCIES IN NORTH AMERICA THAT ARE CANDIDATES FOR LRV OPERATION SPEEDS EXCEEDING 35 MPH Immediately following kick-off of this research effort, the SAIC team participated in a teleconference with the panel and the Transportation Research Board Systems Planning Office (TRB SPO). One major topic of discussion during this teleconference was which transit agencies might be good candidates and be interested in participating in the study. As a result of the conversation, the panel recommended that the research team start Task 1 by contacting the following four transit agencies: 1. Utah Transit Authority (UTA) in Salt Lake City, UT; 2. Santa Clara Valley Transportation Authority (VTA) in Santa Clara / San Jose, CA; Task 1-1—Identify, select, and survey agencies Task 1-2—Identify potential crossings Task 2 Task 1 output: List of potential crossings for further study

TCRP Web-Only Document 53 4 3. New Jersey Transit (Hudson-Bergen Line) in Jersey City, NJ; and 4. Dallas Area Rapid Transit (DART) in Dallas, TX. Utah Transit Authority Staff at UTA said they would be willing to participate in the study, but suggested that North First St. in San Jose or Lancaster Rd. in Dallas would potentially make better test beds for the project. The location suggested in Salt Lake City was 1725 E and Campus Drive; however, this segment is short, and by the time the trains get to the intersection, their speeds are coming down to 35 mph. Further, it is not certain that speeds in excess of 35 mph would be appropriate at this site regardless of the crossing control method. If UTA were selected as the test site, the agency would be willing to help facilitate the data collection effort, but would have to get the local jurisdiction’s agreement. The transit agency would be willing to change out tapes and batteries during video data collection as necessary. As an aside, UTA suggested that perhaps one reason there are so many left-turn collisions is the slower train speeds relative to the parallel traffic (drivers pass the train and then don’t give it much thought). So by increasing the train speeds, he thinks a corresponding decrease in left-turn collisions would result. Santa Clara Valley Transportation Authority The team also spoke with the General Manager of the VTA, as well as the Assistant Director of Maintenance and Security of the VTA who expressed interest in participating in TCRP A-32 and believed that North First St. would be an ideal area for the study. This segment of the LRT line comprises tracks set in rock ballast (not embedded in paving) and situated in the median of North First St. The portion of the right-of-way within the median is owned by the VTA. At most intersections the signalization is owned and operated by the City of San Jose, although a few are under the jurisdiction of Santa Clara County. Train movements at these intersections are given some degree of signal preference over conflicting movement, but they do not preempt the operation in all circumstances. These movements receive what might be called “predictive priority,” a system by which, when an approaching train is detected, the normal signal cycle is altered in various ways to reduce, and in some cases completely avoid, signal delay of train movements without seriously disrupting other vehicle movements. At present, the signal controllers at Trimble Rd. and Brokaw Rd. operate independently of any other intersections, but the city is planning to coordinate the signal controllers along North First St. in the near future to provide a progression for through traffic along North First St. Since these through movements are concurrent with the train movements and utilize the same phase in the cycle, this programming can be expected to be complementary. The VTA also indicated that it was engaged in a number of improvements to mitigate left-turn collisions along North First St. and other intersections. Construction of Phase I of the agency’s improvement project was scheduled for summer 2009, with construction of Phase II of the project scheduled for spring 2010. While the VTA did express concern about the cost of making the improvements, the fact that they are already making some improvements to the intersections in an effort to improve safety may reduce or minimize the costs of participating in the project.

TCRP Web-Only Document 53 5 New Jersey Transit (Hudson-Bergen Line) The SAIC team also spoke with staff at New Jersey Transit (Hudson-Bergen Line). They could not identify any locations where they could increase speeds above 35 mph on the Hudson- Bergen, as the distance between stations is not long enough. Dallas Area Rapid Transit (DART) The SAIC Team spoke with DART staff. DART was interested in the project; however, they were not certain that DART would be willing to or could increase the operating speed. The one potential corridor would be along Lancaster Road between Illinois Ave. and Ledbetter Dr., where stations are spaced approximately 1 mile apart. The current operating speed for LRVs and auto traffic is 35 mph. The major issue with this system is that DART has an agreement with the City not to operate faster than the adjacent roadway; if the speed of the trains were to increase, so would the adjacent roadway speeds. Recommendation Based on the information obtained through the interviews, the research team recommended the VTA as the agency to participate in the study. The VTA was willing and had a corridor that would allow for an increase in train speed. IDENTIFY POTENTIAL CROSSINGS SUITABLE FOR FURTHER STUDY The primary criteria used to select a corridor with crossings suitable for study under the TCRP A-32 project included:  LRT operates in semi-exclusive right-of-way (Types b.2, b.3, or b.4);  Posted speed limit on parallel roadway is more than 35 mph;  Crossings are not currently equipped with flashing lights or automatic gates; and  Distance between stations and adjacent crossings are sufficient to allow LRVs to accelerate from the station to the higher speeds by the crossings and decelerate from the higher speeds through the crossings to the stations. Further discussions with staff at the VTA were conducted to identify potential crossings suitable for study. It was suggested that the North First St. corridor, between Gish and Tasman, may be a good study area. Within this segment, the LRT tracks are situated in a semi-exclusive right-of- way, and there are no flashing lights or automatic gates installed at any of the crossings. The posted speed limit along North First St. within this segment ranges from 35 to 45 mph. Station- to-station spacing averages about 0.5 miles in both the northbound and southbound directions, and maximum train speeds are 35 mph in both directions within the corridor.

TCRP Web-Only Document 53 6 Finally, the distance from a crossing to the nearest LRT station needs to be sufficient to allow LRVs to either accelerate from the station up to the higher speeds prior to entering the crossing (where the nearest station is upstream of the crossing) or to decelerate from the higher speeds at the crossing to the station (where the nearest station is downstream of the crossing). Where the nearest LRT station is upstream of the crossing, the LRV will need to accelerate from a stopped position at the station to 40 mph prior to entering the crossing. Assuming an LRV service acceleration rate of 2.75 mph per second, a minimum distance of approximately 425 feet is required. Where the nearest LRT station is downstream of the crossing, the LRV will need to decelerate from 40 mph at the crossing to a stopped position at the station. Assuming an LRV service deceleration rate of approximately 3 mph per second, a minimum distance of approximately 400 feet is required. The distances between the crossings and the nearest stations are shown in Table 1 and Table 2 for the northbound and southbound directions, respectively. The shaded rows indicate the distances that meet the minimum requirements for the 40 mph test. Table 1. Distances from Crossings to Nearest Station: Northbound Guadalupe Line (Gish Rd. to Tasman Dr.) Crossing Nearest Station(s) Distance to Nearest Station(s) Station South of Crossing (~425’ required to accelerate to 40 mph before crossing)1 Station North of Crossing (~400’ required to decelerate from 40 mph to station) 2 Gish Rd. Gish Station Station at crossing Sonora Ave. Gish Station 654’ south of crossing Skyport Dr. Metro Airport Station -- 1220’ north of crossing Metro Dr. Metro Airport Station Station at crossing Old Bayshore Hwy. Metro Airport Station 240’ south of crossing -- Brokaw Rd. Karina Court Station -- 1080’ north of crossing Karina Ct. Karina Court Station Station at crossing Charcot Ave. Karina Court Station 1150’ south of crossing -- Component Dr. Component Station Station at crossing Trimble Rd. Component Station 930’ south of crossing -- Bonaventura Dr. Bonaventura Station Station at crossing Plumeria Dr. Bonaventura Station 960’ south of crossing -- Orchard Pkwy. Orchard Pkwy Station Station at crossing Montague Expy. Orchard Pkwy Station 610’ south of crossing -- River Oaks Pkwy. River Oaks Station Station at crossing Rio Robles Tasman Station -- 910’ north of crossing Tasman Dr. Tasman Station 130’ south of crossing -- 1 Acceleration rate assumed to be 2.75 miles per hour per second. Acceleration distances were measured from the north end of the station to the stop bar on the northbound approach to the intersection. 2 Deceleration rate assumed to be 3 miles per hour per second. Deceleration distances were measured from the stop bar on the southbound approach to the intersection to the mid-point of the station. Note: Shaded rows represent those distances that are sufficient to allow for acceleration to or deceleration from 40 mph.

TCRP Web-Only Document 53 7 Table 2. Distances from Crossings to Nearest Station: Southbound Guadalupe Line (Tasman Dr. to Gish Rd.) Crossing Nearest Station Distance to Nearest Station Station North of Crossing (~425’ required to accelerate to 40 mph before crossing) 1 Station South of Crossing (~400’ required to decelerate from 40 mph to station) 2 Tasman Dr. Tasman Station -- 290’ south of crossing Rio Robles Tasman Station 760’ north of crossing -- River Oaks Pkwy River Oaks Station Station at crossing Montague Expy. Orchard Pkwy Station -- 1170’ south of crossing Orchard Pkwy. Orchard Pkwy Station Station at crossing Plumeria Dr. Orchard Pkwy Station 1130’ north of crossing -- Bonaventura Dr. Bonaventura Station Station at crossing Trimble Rd. Bonaventura Station 440’ north of crossing -- Component Dr. Component Station Station at crossing Charcot Ave. Component Station 1110’ north of crossing -- Karina Ct. Karina Court Station Station at crossing Brokaw Rd. Karina Court Station 500’ north of crossing -- Old Bayshore Hwy. Metro Airport Station -- 830’ south of crossing Metro Dr. Metro Airport Station Station at crossing Skyport Dr. Metro Airport Station 660’ north of crossing -- Sonora Ave. Gish Station 1206’ south of crossing Gish Rd. Gish Station Station at crossing 1 Acceleration rate assumed to be 2.75 miles per hour per second. Acceleration distances were measured from the south end of the station to the stop bar on the southbound approach to the intersection. 2 Deceleration rate assumed to be 3 miles per hour per second. Deceleration distances were measured from the stop bar on the northbound approach to the intersection to the mid-point of the station. Note: Shaded rows represent those distances that are sufficient to allow for acceleration to or deceleration from 40 mph. In further conversations with the VTA, the research team learned that the VTA had just released a bid for a left-turn and track intrusion mitigation project, which created an interesting and unique opportunity for the TCRP A-32 project. Currently, there are active warning signs that indicate a train is approaching for the North First St. left-turn movements at each intersection, but there are no gates and no indicators other than traffic signals for perpendicular traffic on the North First St. segment. An analysis of historical collision rates showed that left-turn and track- intrusion incidents are the predominant types of incidents on the VTA system. The VTA’s safety improvement project involves the implementation of strategies to reduce left-turn collisions and track intrusions at high-incident locations, several of which are situated along the North First St. corridor under investigation. Specifically, the following intersections are included in the first phase of work:  North First St. and Brokaw Rd.  Capitol Ave. and McKee Rd.  North First St. and Tasman  North First St. and Burton  North First St. and Charcot Ave.  Hostetter Rd. and Capitol Ave.

TCRP Web-Only Document 53 8  Lawrence Expy. and Tasman Dr.  North First Street and Karina Court  Woz Way and San Carlos Street As can be seen in the list of intersections, four of the intersections that will be improved in Phase I of the VTA’s project are located along the North First Street corridor between Gish Road and Tasman Road. Work planned at these locations includes the following:  Install recessed stop bars 20 ft from crosswalk with “KEEP CLEAR” markings downstream of each stop bar;  Install additional signage, including: – Signs that read “Do Not Drive on Tracks” (R15-6 or R15-6a) placed between tracks at crosswalk and oriented towards cross-street left turning traffic;  Install additional pavement markings, including: – Painted “bull nose” with double yellow stripe and two-way yellow retro-reflective raised pavement markers; – Lane line and center line extensions through intersections for cross-street left turn movements;  Replace existing single flash active Train Approaching Sign (W10-7) with a dual flash sign that adds a No Left Turn icon and alternates between the Train icon and the No Left Turn icon;  Install three Caltrans Type Q “markers” / bollards between left-turn lane and trackway between stop bar and crosswalk; and  Install Caltrans Type K-1 “markers” / reflectors between tracks at crosswalk. Phase I design has been reviewed by the California Public Utilities Commission (CPUC), the City of San Jose, and other jurisdictions, with review comments being included in the final design. Phase I is expected to be complete by the end of September 2009, and Phase II construction is projected to begin in spring 2010. As noted in the amplified work plan for this TCRP A-32 project, one of the challenges of the project was to identify a transit agency that was willing to participate not only by increasing the speeds of the trains, but also by implementing safety countermeasures as part of the test of increased speeds. With no financial resources offered to the participating agency to procure and install the safety measures for the TCRP demonstration test, it was recognized that it may be difficult to identify an agency willing to absorb the costs of participation. Therefore, the timing of the VTA improvement project was serendipitous in that the VTA had already gone through the process of determining the most common types of collisions along their LRT line (namely left-turn and track-intrusion); identifying countermeasures to mitigate these incidents; and conducting the planning, reviewing, and approval process for the countermeasures. In many ways, this finding simplified the TCRP A-32 project. Task 2 of the project involved identifying promising safety countermeasures, analyzing the safety and operational aspects of the countermeasures, matching safety measures to specific sites/intersections, and doing a preliminary cost estimate. For the VTA’s particular set of

TCRP Web-Only Document 53 9 improvements, these steps have been largely taken; however, it should be noted that considering the VTA’s safety improvement project did not replace the research that would be conducted for TCRP A-32, rather it complemented it. In moving forward with Task 2, the study team focused on identifying countermeasures that could supplement and/or complement the VTA’s countermeasures. For example, emphasis was placed on identifying countermeasures to mitigate cross-street and pedestrian collisions. Recognizing the benefits of building on the VTA’s improvements, the TCRP A-32 research team considered, as an additional criterion, the intersections that would be improved as part of the VTA’s project. Selecting crossings as test locations that were going to be improved would encourage the VTA’s participation in the TCRP demonstration project. Further, with the high number of intersections being improved, it did not necessarily limit the TCRP A-32 research team from selecting appropriate and representative test sites, rather, it helped the team focus on which ones should be selected. Tables 3 and 4 summarize the crossings along the North First Street corridor (northbound and southbound directions, respectively). Checkmarks indicate which crossings meet each of the criteria specified for selection as a test site, with consideration for the crossings being improved by the VTA. The shaded rows indicate the crossings that met all four of the TCRP A-32 criteria. Five crossings met the criteria in both the northbound and southbound directions:  Brokaw Rd.;  Charcot Ave.;  Trimble Rd.;  Plumeria Dr.; and  Montague Expy. Considering exclusively those crossings that are also VTA improvement sites leaves Brokaw Rd., Charcot Ave., and Trimble Rd. in both the northbound and southbound directions.

TCRP Web-Only Document 53 10 Table 3. Northbound North First Street Crossings Meeting Selection Criteria (Including VTA Improvements) Crossing Original Selection Criteria Additional Criterion Semi- exclusive ROW Posted speed limit >35 mph No flashing lights / gates Sufficient distance between crossing and nearby station(s) VTA Improvements Gish Rd.   Sonora Ave.    Skyport Dr.    Metro Dr.   Old Bayshore Hwy.    Brokaw Rd.      Karina Ct.     Charcot Ave.      Component Dr.    Trimble Rd.     1 Bonaventura Dr.    Plumeria Dr.     Orchard Pkwy.    Montague Expy.     River Oaks Pkwy    Rio Robles    Tasman Drive      1To be improved during Phase II of the VTA’s improvement project (Spring 2010) Note: Rows with lighter shading indicate crossings that meet the four original criteria for possible test sites. Rows with darker shading indicate crossings that meet the four original criteria for possible test sites and are also receiving VTA safety improvements.

TCRP Web-Only Document 53 11 Table 4. Southbound North First Street Crossings Meeting Selection Criteria (Including VTA Improvements) Crossing Original Selection Criteria Additional Criterion Semi- exclusive ROW Posted speed limit >35 mph No flashing lights / gates Sufficient distance between crossing and nearby station(s) VTA Improvements Tasman Drive     Rio Robles     River Oaks Pkwy    Montague Expy.     Orchard Pkwy    Plumeria Dr.     Bonaventura Dr.    Trimble Rd.     1 Component Dr.    Charcot Ave.      Karina Ct.     Brokaw Rd.      Old Bayshore Hwy.    Metro Dr.   Skyport Dr.    Sonora Ave.    Gish Rd.   1To be improved during Phase II of the VTA’s improvement project (Spring 2010) Note: Rows with lighter shading indicate crossings that meet the four original criteria for possible test sites. Rows with darker shading indicate crossings that meet the four original criteria for possible test sites and are also receiving VTA safety improvements. Recommendation Considering the criteria specified for test site selection, as well as the VTA improvement sites, the research team selected the following three crossings as test sites in both the northbound and southbound directions:  Brokaw Rd.;  Charcot Ave.; and  Trimble Rd. The research team did discuss the intersection of North First St. and Montague Expy. with the VTA as a potential test site. This is the sole intersection in the corridor that is not controlled by the City of San Jose; rather, this intersection is controlled by Santa Clara County. However, including this crossing as a test site was potentially problematic for two reasons. First, from a jurisdictional standpoint, selection of this site would require buy-in, approvals, and cooperation from a third agency. Further, the Montague Expressway is a major thoroughfare on which the county wants to keep traffic moving. Therefore, the priority at the intersection of North First St. and Montague Expy. is given to the Montague Expy. Knowing that the priority is not given to North First St. or the LRT, from a technical standpoint, it will be difficult to test higher speeds through this crossing.

TCRP Web-Only Document 53 12 The only other crossing that met all of the TCRP A-32 criteria for selection of a test site was the intersection of North First St. and Plumeria Dr. This intersection is the next four-way intersection to the north of the crossing at Trimble. Due to the similarity and proximity of these two intersections, it seemed more prudent to select the crossing at Trimble Rd. as a test site simply because it is one of the VTA’s improvement sites. If the Plumeria crossing had been selected, the VTA would have then had to improve that intersection as well. Summary of Study Segment and General Intersection Design and Operational Characteristics The “study segment” stretches from Brokaw Rd. north to Trimble Rd., a distance of about 1 mile, and traverses five signalized intersections: Brokaw Rd., Karina Ct., Charcot Ave., Component Dr., and Trimble Rd. Figure 2 shows the study segment as it relates to the larger San Jose area, and Figure 3 shows the specific study intersections within the study segment as well as their relation to the other two signalized intersections within the study segment. Figure 2. Study Area Location

TCRP Web-Only Document 53 13 Figure 3. Study Intersections Intersection Geometrics Figure 4, Figure 5, and Figure 6 show the geometry of the three study sites using aerial imagery. Figure 4. Aerial View of North First Street and Brokaw Rd.

TCRP Web-Only Document 53 14 Figure 5. Aerial View of North First Street and Charcot Ave. Figure 6. Aerial View of North First Street and Trimble Rd.

TCRP Web-Only Document 53 15 Table 5 summarizes the general geometric characteristics of the three study intersections. The designs of the study intersections, in general, provide separate lanes for the different movements (left-turn, through, right-turn). Two of the intersections are at right angles, with the intersection at Brokaw Rd. being at a slight skew (approximately 75 degrees). The intersection designs provide sufficient sight distance for all four approaches to each of the three intersections. Table 5. Summary of Geometric Characteristics of Intersections within the Study Segment Brokaw Charcot Trimble Total # of Major Street NB lanes 4 4 4 LT ......................................................................... 1 2 2 (Length of LT bay) ............................................. 300' 300' 300' THRU .................................................................... 2 2 2 RT ......................................................................... 1 shared shared Crosswalk ............................................................. no yes yes Bike lane ............................................................... no yes yes Total # of Major Street SB lanes 3 3 4 LT ......................................................................... 1 1 2 (Length of LT bay) ............................................. 275' 300' 300' THRU .................................................................... 2 2 2 RT ......................................................................... narrow area narrow area shared Crosswalk ............................................................. yes yes yes Bike lane ............................................................... yes yes yes Total # of Minor Street EB lanes 6 4 5 LT ......................................................................... 2 2 1 (Length of LT bay) ............................................. 300' 450' 300' THRU .................................................................... 3 2 3 RT ......................................................................... 1 narrow area 1 Crosswalk ............................................................. yes yes yes Bike lane ............................................................... yes no yes Total # of Minor Street WB lanes 4 4 5 LT ......................................................................... 2 2 2 (Length of LT bay) ............................................. 240' 250' 300' THRU .................................................................... 2 2 3 RT ......................................................................... 1 narrow area 1 Crosswalk ............................................................. yes yes yes Bike lane ............................................................... yes no yes Distance to nearest NB station 1080' N of intersection 1150' S of intersection 930' S of intersection Distance to nearest SB station 500' N of intersection 1110' N of intersection 440' N of intersection Approximate intersection angle 75 degrees 90 degrees 90 degrees 4-way 4-way 4-way

TCRP Web-Only Document 53 16 Traffic Volumes Table 6 shows the traffic volumes by turning movement. Traffic volumes were collected in 2008 and 2009, and according to the City of San Jose, traffic volumes have not changed by any noticeable margin since they collected these data. Peak hourly traffic volumes in the northbound direction along North First St. alone range from 533 vehicles per hour (vph) to 1,416 vph. The southbound peak hourly volumes range from a low of 400 vph to a high of 1,420 vph. On the cross-streets, the highest peak hourly volume, 1,786 vph between the hours of 8:00 a.m. and 9:00 a.m., occurs on the westbound Brokaw Rd. approach to North First St. The volumes of left-turn movements from North First St. across the track way ranged from a low of 46 vph on the southbound approach at Charcot Ave. to a high of 256 vph on the northbound approach at Trimble Rd. Table 6. Traffic Volumes at Study Intersections on North First Street Intersection of North First St. @ Northbound AM (PM) Southbound AM (PM) Eastbound AM (PM) Westbound AM (PM) Date Counted and Total Peak Hourly Volume AM (PM) Peak Hours RT THR LT RT THR LT RT THR LT RT THR LT Brokaw Rd. 309 (295) 660 (330) 106 (53) 120 (255) 231 (930) 85 (224) 83 (60) 672 (840) 542 (314) 385 (186) 1072 (918) 329 (463) 9/23/08 4616 (4919) 8:00-9:00 AM 5:00-6:00 PM Charcot Ave. 100 (58) 564 (354) 75 (121) 205 (527) 289 (601) 46 (93) 11 (81) 602 (216) 532 (203) 55 (37) 166 (593) 45 (107) 3/24/09 2699 (3000) 7:45-8:45 AM 5:00-6:00 PM Trimble Rd. 165 (71) 988 (519) 256 (252) 23 (121) 303 (923) 61 (130) 140 (119) 701 (984) 194 (117) 43 (36) 958 (767) 305 (241) 9/23/08 4165 (4285) 8:00-9:00 AM 4:45-5:45 PM Source: City of San Jose Department of Streets and Traffic. Pedestrian and Bicycle Volumes All intersections have crosswalks and pedestrian signal displays. The pedestrian signals are timed to allow pedestrians to cross and clear the total width of North First St. from curb to curb in a signal pedestrian phase. Walk indications are displayed for at least 7 seconds before the Flashing Don’t Walk signal indication is displayed. None of the pedestrian signals have countdown displays. The number of pedestrians crossing at any of the intersection approaches ranges from 5 to 15 per hour. It is worth noting that the east-west, i.e., conflicting movements with light rail, pedestrian volumes at the intersections during the peak hours varied from 2 to 11

TCRP Web-Only Document 53 17 pedestrians per hour. Bicyclists are very few as well. Bicycle lanes are provided throughout the corridor, but less than 5 bicyclists per hour are usually observed during the peak period. LRT Operational Data Light rail operates at up to 35 miles per hour (mph) in the study section. The posted speed limit on North First St. at the study sites is 45 mph. Light rail operates with approximately 7 to 8 minute headways in both the north and south direction during the peak hours. Traffic Signal Timing The current operations at all three intersections include an eight-phase sequence with protected left-turn phasing for both North First St. and the cross-streets. All intersections have exclusive left-turn lanes. All left turns on the cross-streets have a lead-lead left-turn phase sequence. On North First St., the left-turn phase sequence is all lead-lead with the exception at Charcot Ave., which operates in a lag-phase sequence. All signals use Model 2070 controllers and special software by Fourth Dimension™ for transit signal priority (TSP). The TSP function in the software allows the controller to change left-turn phasing, skip phases, and also shorten phase timing in order to accommodate signal priority request by the VTA light rail vehicles.

Next: Chapter 3: Assessment of the Operational and Safety Aspects of Existing, Alternative, and Possible Supplemental Traffic Control Devices »
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TRB’s Transit Cooperative Research Program (TCRP) Web-Only Document 53: Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH presents the findings of a micro-simulation modeling study that explored the impacts of higher light rail vehicle speeds on intersection safety.

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