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Light Rail Vehicle Collisions with Vehicles at Signalized Intersections (2008)

Chapter: Chapter Three - Countermeasures to Mitigate Collisions Between Light Rail Vehicles and Motor Vehicles at Signalized Intersections

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Suggested Citation:"Chapter Three - Countermeasures to Mitigate Collisions Between Light Rail Vehicles and Motor Vehicles at Signalized Intersections." National Academies of Sciences, Engineering, and Medicine. 2008. Light Rail Vehicle Collisions with Vehicles at Signalized Intersections. Washington, DC: The National Academies Press. doi: 10.17226/14215.
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Suggested Citation:"Chapter Three - Countermeasures to Mitigate Collisions Between Light Rail Vehicles and Motor Vehicles at Signalized Intersections." National Academies of Sciences, Engineering, and Medicine. 2008. Light Rail Vehicle Collisions with Vehicles at Signalized Intersections. Washington, DC: The National Academies Press. doi: 10.17226/14215.
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Suggested Citation:"Chapter Three - Countermeasures to Mitigate Collisions Between Light Rail Vehicles and Motor Vehicles at Signalized Intersections." National Academies of Sciences, Engineering, and Medicine. 2008. Light Rail Vehicle Collisions with Vehicles at Signalized Intersections. Washington, DC: The National Academies Press. doi: 10.17226/14215.
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Suggested Citation:"Chapter Three - Countermeasures to Mitigate Collisions Between Light Rail Vehicles and Motor Vehicles at Signalized Intersections." National Academies of Sciences, Engineering, and Medicine. 2008. Light Rail Vehicle Collisions with Vehicles at Signalized Intersections. Washington, DC: The National Academies Press. doi: 10.17226/14215.
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Suggested Citation:"Chapter Three - Countermeasures to Mitigate Collisions Between Light Rail Vehicles and Motor Vehicles at Signalized Intersections." National Academies of Sciences, Engineering, and Medicine. 2008. Light Rail Vehicle Collisions with Vehicles at Signalized Intersections. Washington, DC: The National Academies Press. doi: 10.17226/14215.
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Suggested Citation:"Chapter Three - Countermeasures to Mitigate Collisions Between Light Rail Vehicles and Motor Vehicles at Signalized Intersections." National Academies of Sciences, Engineering, and Medicine. 2008. Light Rail Vehicle Collisions with Vehicles at Signalized Intersections. Washington, DC: The National Academies Press. doi: 10.17226/14215.
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Suggested Citation:"Chapter Three - Countermeasures to Mitigate Collisions Between Light Rail Vehicles and Motor Vehicles at Signalized Intersections." National Academies of Sciences, Engineering, and Medicine. 2008. Light Rail Vehicle Collisions with Vehicles at Signalized Intersections. Washington, DC: The National Academies Press. doi: 10.17226/14215.
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Suggested Citation:"Chapter Three - Countermeasures to Mitigate Collisions Between Light Rail Vehicles and Motor Vehicles at Signalized Intersections." National Academies of Sciences, Engineering, and Medicine. 2008. Light Rail Vehicle Collisions with Vehicles at Signalized Intersections. Washington, DC: The National Academies Press. doi: 10.17226/14215.
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Suggested Citation:"Chapter Three - Countermeasures to Mitigate Collisions Between Light Rail Vehicles and Motor Vehicles at Signalized Intersections." National Academies of Sciences, Engineering, and Medicine. 2008. Light Rail Vehicle Collisions with Vehicles at Signalized Intersections. Washington, DC: The National Academies Press. doi: 10.17226/14215.
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Suggested Citation:"Chapter Three - Countermeasures to Mitigate Collisions Between Light Rail Vehicles and Motor Vehicles at Signalized Intersections." National Academies of Sciences, Engineering, and Medicine. 2008. Light Rail Vehicle Collisions with Vehicles at Signalized Intersections. Washington, DC: The National Academies Press. doi: 10.17226/14215.
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Suggested Citation:"Chapter Three - Countermeasures to Mitigate Collisions Between Light Rail Vehicles and Motor Vehicles at Signalized Intersections." National Academies of Sciences, Engineering, and Medicine. 2008. Light Rail Vehicle Collisions with Vehicles at Signalized Intersections. Washington, DC: The National Academies Press. doi: 10.17226/14215.
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Suggested Citation:"Chapter Three - Countermeasures to Mitigate Collisions Between Light Rail Vehicles and Motor Vehicles at Signalized Intersections." National Academies of Sciences, Engineering, and Medicine. 2008. Light Rail Vehicle Collisions with Vehicles at Signalized Intersections. Washington, DC: The National Academies Press. doi: 10.17226/14215.
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11 This chapter focuses on the countermeasures used to mitigate collisions between LRVs and motor vehicles at signalized intersections. According to Coifman and Bertini (3), a counter- measure for mitigating collisions between LRVs and motor vehicles should address motorists’ expectations at conventional intersections as well as work to keep motorists within the law at LRT crossings. They go on to state, A successful collision countermeasure should accomplish at least one of the following goals: Remind the driver that there are special risks in the given situation Physically prevent the driver from taking these additional risks (3, p. 4). Table 3 shows a variety of countermeasures, found in a review of the literature and through interviews with selected transit agencies, which have been tested, implemented, or suggested to mitigate collisions between LRVs and motor vehicles at signalized intersections. The sections that follow provide details on each of these countermeasures. PHYSICAL BARRIERS Physical barriers provide physical separation between move- ments. Transit agencies have employed a variety of physical barriers, including gates, bollards, and delineators to provide physical separation between LRV and motor vehicle move- ments. These countermeasures are discussed here. Gates An FTA-sponsored study was undertaken in 2002 to investi- gate the use of railroad crossing gates to reduce collisions between LRVs and motor vehicles at intersections where streets run parallel to LRT and motorists are permitted to make left turns across the tracks (8). The two types of gates included in the study were: • Left-turn gates, which can be used to physically prohibit motorists from turning left in conflict with an LRV. Left- turn gates can be installed parallel to the tracks (along the line separating the left-turn lane from the tracks in a median-running environment) or at 90 degrees to the left- turn lane directly in front of the first left-turn vehicle waiting to turn. Calgary Transit has installed both types of left-turn gates. • Four-quadrant gates—From the review of a variety of gates conducted in the FTA study, full-closure, four- quadrant crossing gates were selected as the best option as they offered a number of advantages over the other gate systems reviewed. A full-closure, four-quadrant cross- ing gate system was installed in October 1998 at the 124th Street intersection in south central Los Angeles to deter motorists from making left turns around lowered railroad crossing gates. During the experimental phase, data recorded for the first 6 months of operation at the 124th Street intersection showed that the four-quadrant gate approach resulted in a 94% reduction in the number of risky moves by motorists using the intersection. The use of four-quadrant gates has continued in Los Angeles and they have continued to have success with this counter- measure. Four-quadrant gates are effective in semi- exclusive rights-of-way, but not for street operations. Knock-Down Bollards Coifman and Bertini (3) note that at a typical median LRT crossing with left-turn pocket lanes, the left-turn lanes are often separated from the trackway by a narrow curb, which may end before the intersection to allow for installation of and passage for a pedestrian crosswalk. With the end of this curb at the crosswalk, motorists frequently enter the LRV dynamic envelope during their left turns. The problem is compounded when drivers cross the stop bar and stop at the near side of the crosswalk. In these situations, knock-down bollards can pro- vide a safe and effective means for restricting automobile movements in the crosswalk, effectively reducing the length of the potential LRV–motor vehicle collision zone. Raised Medians or Delineators In side-running, semi-exclusive alignments, raised medians or delineators can be installed to deter left-turn motorists from driving around lowered automatic gates during their turns. In this application, the raised medians or delineators are installed on the cross street, perpendicular to the tracks, between the trackway and the intersection. CHAPTER THREE COUNTERMEASURES TO MITIGATE COLLISIONS BETWEEN LIGHT RAIL VEHICLES AND MOTOR VEHICLES AT SIGNALIZED INTERSECTIONS

Retractable Delineators or Barriers Retractable delineators can be installed to block unwanted vehicular movements in a number of applications and could be particularly useful where there is insufficient space for the installation of gates. The Los Angeles Department of Trans- portation (DOT) has investigated the use of retractable delin- eators to block traffic making left turns across the Long Beach Blue Line tracks at certain signalized intersections. Discus- sions between the Los Angeles DOT and a supplier in the early 2000s concluded that the particular retractable delineators 12 available at that time could not be used for the left-turn barrier application as they would not be able to perform the number of daily “up and down” cycles required (more than 200/day) at the crossing (8). Several other agencies have explored retractable delin- eators or barriers since that time. METRO in Houston is currently testing another type of retractable delineator for use in keeping motorists out of the shared LRV–left-turn lane when trains are approaching. The Michigan DOT, FRA, and Norfolk Southern Railway, in cooperation with Category Counterm easure 1 Agency Exam ple(s) 2 Gates (left-turn gates, four-quadrant gates) Calgary Transit, LACMTA Knock-down bollards DART Raised med ians/delineators TriMet, DART, NFTA (Buffalo) Physical Barriers Retractable delineators/barriers Michigan DOT Active train-approaching warning signs TriMet, DART, LACMTA Active turn-prohibition signs Houston METRO, TriMet Overhead lane-use control signs LACMTA Use and placem ent of static signs Sacram ento RT, TriMet Traffic Signs 2nd train com ing warning sign Maryland MTA Red left-turn arrows Denver RTD, TriMet Green arrow aspects for through traffic New Jersey Transit, TriMet In-roadway lights Houston METRO Programmable visibility signal heads TriMet LRT signals with form at and color different from traffic signals LACTMTA, Santa Clara VTA Signal Displays Far-side LRV signals TriMet All-red traffic signal phase LACMTA Lagging left turns LACMTA, TriMet LRV ìq ueue jum p” or “head start” Utah Traffic Signal Phasing Signal pre-em ption phasing TriMet Contrasting pavem ent treatments Houston METRO Crosshatch pavement markings New Jersey Transit Lane-use ma rkings (arrows) San Francisco MUNI Pavem ent Markings/Treatments Extending/repositioning pavem ent treatments/markings Denver RTD Public outreach ma terials LACMTA, Denver RTD Public Outreach/Education State driver’s license handbooks California Police presence LACMTA, Houston METRO Enforcem ent Photo enforcem ent LACMTA Lower train speeds TriMet Train-m ounted cam eras Sacram ento RT, Houston METRO Other LRV operator defensive driving New Jersey Transit, San Diego Metropolitan Transit System 1 These countermeasures may not be app licable in all situations, such as emergency or reverse-running operations. 2 The agencies noted are just a few examples of those using the countermeasures. Therefore, the use of the countermeasures is not necessarily limited to the agencies listed here. TABLE 3 COUNTERMEASURES USED BY TRANSIT AGENCIES TO MITIGATE COLLISIONS BETWEEN LRVS AND MOTOR VEHICLES AT SIGNALIZED INTERSECTIONS

13 the FHWA, are currently testing a type of retractable barrier to discourage drivers from driving around the crossing gates at a crossing in Wayne County (9). The delineators are activated by a signal from the crossing gate system and reach their full deployment in about 6 s (Figure 2). Metro in Los Angeles is interested in the possible trial application of these same retractable barriers across the far side of the marked crosswalk to block the left-turn pocket lane. Los Angeles noted a number of potential issues with this appli- cation, including interaction of the delineators with pedes- trians in the crosswalk, vehicles encroaching into the cross- walk, life expectancy of the delineators with the number of up-and-down cycles required for light rail operations, and failure of the delineators. TRAFFIC SIGNS McCormick and Sanders (cited in reference 3) noted that most linguistic research indicates that active, affirmative statements generally are easier to understand than passive or negative statements. In addition, Whitaker and Stacey (cited in refer- ence 3) found that permissive stimuli (e.g., “do”) produced faster responses than prohibitive stimuli (e.g., “do not”). In the METRORail Traffic Safety Assessment (4), it was noted that the traffic control devices in use placed an emphasis on pro- hibited rather than permitted movements and the possibility of driver confusion about where turns were allowed and where through movements were the only permitted movements. The recommendation to METRO was displaying permitted move- ments provides positive guidance, which could ease decision load on drivers and could result in fewer last-second decisions in complex driving conditions. Specific recommendations for signage included • Overhead lane-use control signs in place of extra turn- prohibition signs; and • (Turn) ONLY signs where there was only one permit- ted movement at an intersection. Active Train-Approaching Warning Signs Active train-approaching warning signs supplement the turn arrow signal indication, which serves as the primary regulatory control device at the intersection. These active signs warn motorists of the increased risk associated with violating the turn arrow signal indication (1). Transit agencies have imple- mented a variety of active “train-approaching” warning signs, ranging from the use of pedestrian heads that display the words, “TRAIN” or “TRAIN COMING,” to the use of the W10-7 (Light Rail Transit Approaching) LRV-activated flash- ing blank-out signs suggested in the Manual on Uniform Traf- fic Control Devices for Streets and Highways (MUTCD) (10) (Figures 3 through 5). LACMTA uses the MUTCD sign, but supplements the LRV icon with the word “TRAIN” (Figure 6). In most applications, the icon sign flashes to draw more attention from motorists. Some agencies even use a varia- tion of the orientation of the LRV icon depending on which approach the sign is targeting. For example, in Portland (Oregon), motorists in the left-turn pocket lanes see an icon portraying the front of an LRV, whereas motorists on the cross-street approach to the tracks see an icon portraying the side or profile view of an LRV. The orientation of the LRV icon is meant to provide additional directional information to the motorists. At some agencies, these signs have evolved over the years depending on current practice and available funding. Many transit agencies, including TriMet, Houston METRO, and LACMTA have found these signs to be an effective means FIGURE 2 Retractable barriers under test in Wayne County, Michigan (Courtesy: Michigan Department of Transportation). FIGURE 3 MUTCD W10-7 (Light Rail Transit Approaching) sign.

14 pedestrian heads to display the words, “No Left Turn,” to the use of the “No Right/Left Turn Across Tracks” activated blank-out signs suggested in the MUTCD (R3-1a, R3-2a signs shown in Figure 7) (10). To restrict turns when an LRV is approaching, some agencies use the activated blank- out versions of the MUTCD no right- or left-turn symbol sign (R3-1/R3-2) shown in Figure 8, as was recommended in TCRP Report 17 (1). Sacramento RT formerly used acti- vated blank-out signs with the words, “No Left/Right Turn.” Currently they use the activated blank-out versions of the R3-1 and R3-2 symbol signs, as shown in Figure 9, which they believe work better than the text versions of the signs. METRO in Houston uses no right- or left-turn activated blank-out symbol signs that incorporate the tracks symbol, as illustrated in Figures 10 and 11. FIGURE 4 Train-activated warning sign—Hiawatha Line, Minneapolis (Courtesy: Calvin Henry-Cotnam). FIGURE 5 Train-activated warning sign in Houston. FIGURE 6 Train-activated warning sign in Los Angeles. FIGURE 7 MUTCD R3-1a and R3-2a signs. of reducing left-turn collisions. Newer LRT systems have benefited from the use of these signs by older LRT systems and have incorporated the latest technology into their systems’ designs. Active turn-prohibition signs are generally used where left and right turns are permitted across the tracks except when an LRV is approaching. Transit agencies have implemented a variety of active turn-prohibition signs, ranging from the use of

15 Overhead Lane-Use Control Signs Where motorists make left turns from the wrong lane (usually in the case of mixed-use operations), the use of overhead lane- use control signs can provide positive guidance and can indi- cate the allowable movements from each lane. The lane-use signs can be supplemented with the word ONLY when only one movement is permitted from the lane. Figure 12 shows the use of the MUTCD overhead lane-use control signs R3-5 (through-only) and R3-5a (left-turn only). Figure 13 shows the use of an overhead lane-use control sign in Houston, which incorporates the tracks symbol. Overhead advance intersection lane-use control signs can also be used to provide advance warning to motorists (4). Use and Placement of Static Signs Signalized intersections that incorporate LRT by design are complex intersections. When a multitude of signs are present at these intersections it can cause visual clutter, increase driver information processing time, and increase the potential for missing important information regarding permitted or prohib- ited movements and LRT presence. Consolidating traffic sign messages where possible and eliminating unnecessary redun- dancies can reduce the visual clutter as well as the chance of driver error (4). One way to reduce the number of signs placed at the intersection is to use the MUTCD combination “No left- turn/No U-turn” symbol sign (R3-18) instead of two separate signs (Figure 14). FIGURE 8 MUTCD R3-1 and R3-2 signs. FIGURE 9 No right-turn activated blank-out sign in Sacramento (Courtesy: Sacramento Regional Transit District). FIGURE 10 No left-/right-turn-activated blank-out signs with tracks symbol (Courtesy: Metropolitan Transit Authority of Harris County, Texas). FIGURE 11 No right-turn-activated blank-out sign with tracks symbol in Houston. FIGURE 12 MUTCD overhead lane-use control signs. FIGURE 13 Overhead lane-use control signs in Houston (Courtesy: Houston METRO).

16 section, the gates remain down as the second train passes through the crossing; however, if the first train has finished crossing the intersection, the presence of the second train causes the gates to come back down before reaching their full vertical position (11). As part of a demonstration project sponsored by TRB, the Maryland Mass Transit Administration (MTA) tested a sec- ond train coming warning sign. The active sign flashed the word “WARNING,” which was followed by a steady appear- ance of the words, “2nd Train Coming,” which was followed by an animation of an LRT moving through a crossing (see Figure 17). This display was supplemented with flashing bea- cons to attract motorists’ attention to the new sign (11). The sign was mounted on the cantilever arm at a heavily trav- eled highway rail intersection where trains operate at a speed of 50 mph. Risky behaviors were observed during a period before the sign was installed and during two periods after the sign was installed. Overall, the findings demonstrated that during the second 30-day period after the sign was installed, less risky behavior was observed than during the first “after” period. A significant reduction of 26% was noted in the fre- quency of vehicles that crossed the tracks after the first LRV cleared the crossing while the gates were ascending but had not reached the full upward position, and before the gates descended again on activation of the circuits by the second train. However, it was still observed that the majority of drivers attempted to travel through the crossing as soon as the gates began to ascend, with or without the indication of a second train coming. Left Turns Can Be Accomplished by Making Signs Showing Three Consecutive Right Turns In addition to the signs used by transit agencies to mitigate col- lisions between LRVs and motor vehicles, the Texas Trans- portation Institute (TTI) recommended that Houston METRO make use of signs showing that left turns can be accomplished FIGURE 14 Combination no left-turn and no U-turn sign (MUTCD R3-18 sign). FIGURE 15 Example of sign clutter and misplacement. FIGURE 16 Use of the MUTCD No Turns sign. FIGURE 17 Second train coming warning sign (Courtesy: Ziad Sabra, Sabra, Wang and Associates, Inc.). Sign placement can also help motorists focus on the information that is intended for them. For example, left- and U-turn-prohibition signs should be placed in the median, on the far-left side, or on the left side of the signal mast arm (not on the right side of the intersection). Figure 15 shows an example of the No U-turn sign placed over the far-right lane of traffic and where the combination No left-turn/No U-turn sign would be appropriate to reduce sign clutter. Likewise, right-turn-prohibition signs should only be placed on the right side of the intersection. When both right and left turns are pro- hibited at an intersection, the MUTCD No Turns sign (R3-3) can be placed on the signal mast arm (4) (Figure 16). Second Train Coming Warning Sign One of the most challenging aspects that the Baltimore LRT system experienced after start-up was the “second train com- ing” phenomenon that occurs on double track crossings. This phenomenon occurs when two trains traveling in opposite directions activate the crossing equipment within seconds of each other. If the first train has not finished crossing the inter-

17 by making three consecutive right turns. Along some LRT alignments, there may be few locations where left turns are permitted across the tracks, which could lead to increased pressure for motorists to turn left where left turns are possible, even if they are prohibited. Posting advanced signs showing motorists that they can accomplish upcoming left turns by making three consecutive right turns starting beyond the cross street might help reduce the number of left-turn violations. This can be iterated in public education materials by including instructions for accomplishing a left turn by making three suc- cessive right turns (4). SIGNAL DISPLAYS Red Left-Turn Arrows Red left-turn arrows (as shown in Figure 18) provide more positive guidance to motorists than red balls. At a few inter- sections in Denver with LRT, where left turns are made from a one-way street onto another one-way street, left turns on red are not allowed owing to the LRT tracks. In RTD’s experi- ence, the red left-turn arrow signal display has worked better than the combination of a red ball and static signs stating “No Turn on Red.” Motorists seem to have more respect for the red arrow signal display than the static sign, as they will violate the signs more often than the signals. Green Arrow Aspects for Through Traffic In an effort to provide positive guidance, the METRORail Traffic Safety Assessment report recommended the use of green arrow aspects on traffic signal heads instead of green balls and redundant turn-prohibition signs (4) (Figures 19 and 20). Coifman and Bertini also recommend the use of green arrow aspects for through traffic to reduce the chance that a driver turning left will mistake the through traffic signals for the turning movement, which can happen for a number of rea- sons. First, there are generally more through signals than turn arrows. Second, the surface area of the green ball is greater than the surface area of an arrow, making it more prominent. Third, the transmittance of a green filter is greater than that of a red filter. For these reasons, the through traffic signal balls have a greater probability of being perceived by a driver than do the left-turn arrow signals (3). If green arrow aspects are used for through movements, a green ball should still be used in the right lane where right turns are permitted across the par- allel crosswalk pedestrian movement. In-Roadway Lights In-roadway lights are defined in the MUTCD (10) as “special types of highway traffic signals installed in the roadway surface to warn road users that they are approaching a condition on or adjacent to the roadway that might not be readily apparent and might require the road users to slow down and/or come to a stop” (10). In 2006, Houston METRO began testing an application of in-roadway lights to get motorists’ attention to stop at the red lights on the cross-street approaches to sig- nalized intersections with LRT and to reduce encroachment into the intersection. The lights being tested by METRO are red, installed along the stop bar, and flicker at a fast rate. An application of the in-roadway lights at one intersection in Houston is illustrated in Figure 21, as an LRV approaches from the right. Over the past year, METRO has installed in-roadway lights at 11 intersections and experienced only two red-light running accidents at the 11 intersections since installation (the lights have been installed at the intersections on average for about 11 months). This compares with about eight red-light running accidents per year on average at these same inter- sections for the previous 3-year period, a reduction METRO views as significant. Although this application was to prevent red-light running on the cross street, it could have the same effect, for some align- ments, for left-turning traffic. LACMTA reported that they are currently considering using the in-roadway lights to mitigate left-turn motorist violations at intersections with LRV. FIGURE 18 Use of a red arrow to prohibit the left-turn movement. FIGURE 19 Use of green arrow aspects for through traffic. FIGURE 20 Use of arrows to control traffic movements.

18 Far-Side Light Rail Vehicle Signals When LRT bar signals are placed in advance of an inter- section (i.e., near-side signals), LRVs are required to stop before reaching the intersection. By installing the bar signals on the far side of the intersections and instructing LRV opera- tors to pull up to the stop bar on a red indication, it establishes an LRV presence at the intersection and could help to reduce illegal left turns (4). TRAFFIC SIGNAL PHASING Traffic signal phasing deals with the order in which the per- mitted and protected movements are allocated at signalized intersections. The following traffic signal phasing schemes have been recommended specifically to mitigate collisions between LRVs and motor vehicles. All-Red Traffic Signal Phase The all-red traffic signal phase holds all vehicular traffic on red while the LRV passes through the intersection. The purpose of the all-red phase is to discourage illegal left-turn movements across the LRV tracks by prohibiting all movements while the LRV is present at the intersection. There is evidence to suggest that motorists in the left-turn lanes may cue off of the cross- street traffic in anticipation of a leading left turn, or that they may cue off of the parallel through traffic movements or sig- nal indications rather than focusing on the left-turn signal indi- cation (1,3). By holding all traffic on red, motorists are less likely to make illegal movements across the tracks. Transit agencies including TriMet, LACMTA, and Houston METRO have implemented all-red phases at signalized intersections along their LRT alignment. Lagging Left Turns Motorists sometimes initiate their left turns as soon as the cross-street traffic receives the red, but before they receive the green arrow indication (1). This is particularly common at locations with leading left-turn phases, as motorists cue off the cross-street signals in anticipation of the leading left turn [Coifman and Bertini (3) noted that LRT accident reports suggest that this is occurring]. When the leading left-turn sig- nal phase is pre-empted by an approaching LRV, the motorist anticipating the leading left turn could be in conflict with the LRV. Likewise, some motorists will “sneak” through the inter- section at the end of their protected turn phase. When the protected left-turn phase is a leading left turn, this can put motorists in danger of being struck by an LRV approaching during the parallel through traffic’s green phase. The use of lagging left turns can mitigate the possibility of collisions in both of these situations. Lagging left turns help FIGURE 21 In-roadway lights in Houston (Courtesy: METRO). FIGURE 22 LRT signals (Courtesy: Jon Bell). Programmable Visibility Signal Heads Programmable visibility signal heads reduce the visibility of the signals from adjacent lanes. These signal heads can be used to reduce the likelihood that motorists in the left-turn lane will cue off the signals for the through traffic (3,4). Light Rail Transit Signals with Format and Color Different from Traffic Signals The use of LRT signals that look similar to traffic signals (e.g., colored ball, “T,” or “X” signals) tend to confuse motorists (e.g., motorists may interpret a green “T” signal that is visible from a left-turn pocket as a left-turn arrow). There- fore, LRT signals should be clearly distinguishable from con- ventional traffic signal displays in terms of format and color and their indications should be meaningless to motorists with- out the provision of supplemental signs. LRT bar signals are white, monochrome bar signals that are separated in space from motor vehicle signals (1) (Figure 22).

19 remove the anticipation of making the left turn by allowing protected left turns at the end of the through green phase, rather than at the beginning. Likewise, left-turn motorists who sneak through the intersection during a lagging left-turn phase will not be in conflict with an LRV. Light Rail Vehicle “Queue Jump” or “Head Start” An LRV queue jump can be accomplished by giving LRVs a brief head start of 2 to 4 s before motor vehicle traffic after a red signal. This head start helps establish LRV presence at intersections and was recommended to Houston METRO to help prevent illegal left turns in front of LRVs (4). Signal Pre-Emption Phasing Transit priority that skips a normal signal phase can catch drivers by surprise. If possible, the normal sequence of signal phases should not be disrupted (3). This can be accomplished by returning to the phase that was pre-empted by the LRV. PAVEMENT MARKINGS AND/OR TREATMENTS Contrasting Pavement Treatments Contrasting pavement treatments include colored concrete, brick, etc. (Figure 23). They are used to improve the con- spicuity of the tracks and to delineate the dynamic envelope of the train. Along the Metro Blue Line in Los Angeles, at loca- tions with side-running operation, drivers on the cross-street approach to the intersection encroach into the dynamic enve- lope of the train. To keep drivers back, LACMTA enhanced the crosswalk before the tracks to make it more noticeable by using a colored concrete pattern. Contrasting pavements on the near and far sides of the stop bar can also be used to increase the visibility of the stop bar (4). Crosshatch Pavement Markings Some agencies have implemented crosshatch pavement mark- ings at intersections to mitigate collisions between LRVs and motor vehicles. Crosshatch pavement markings are used to designate an area on the pavement where motor vehicles should not be stopped, such as on approaches to LRT tracks where drivers have a tendency to encroach on the tracks. Lane-Use Markings (Arrows) Where motorists make left turns from the wrong lane, lane-use markings can be placed in individual lanes on the approach to the intersections. By providing markings on the pavement, drivers are more likely to see them. Markings should be placed so that they are not concealed by the first one or two vehicles in the queue. The lane-use arrows can be supplemented with the word ONLY when only one movement is permitted from the lane (4). Extending or Repositioning Pavement Treatments and Markings To keep right-turning motorists from crossing the stop bar and encroaching into the dynamic envelope of the train, RTD in Denver extended the concrete apron of the train 8 ft into the right-turn lane, moved the stop bar 5 ft further upstream (from 15 ft to 20 ft), and applied new pavement markings. As a result of the treatments, risky behaviors by motorists decreased significantly (7). Reducing Number of Transverse Roadway Markings In addition to the pavement marking and/or treatment counter- measures used by transit agencies to mitigate collisions between LRVs and motor vehicles, the TTI recommended that METRO reduce the number of transverse roadway markings in certain locations. Too many transverse markings on the roadway in the vicinity of the intersection can make it difficult for motorists to distinguish one from another, such as near intersections where there is a crosswalk, stop bar, and railroad markings. Without a clear definition of the stop line, drivers may be confused as to where to stop. The number of transverse lines can be reduced by using an alternative pattern for cross- walk markings (4). PUBLIC OUTREACH AND EDUCATION Public education plays a vital role in LRT safety in locali- ties where the public may not be familiar with LRT opera- tions (4) and, according to Coifman and Bertini (3, p. 10), “An FIGURE 23 Contrasting pavement treatment in Houston (Courtesy: Houston METRO).

education program is critical for start-up systems where drivers are unfamiliar with street railways.” Recommendations for public education and outreach programs from the METRORail Traffic Safety Assessment (4) included • Focusing the public education and outreach program on how and when to make left turns along the LRT line and the importance of obeying traffic regulations. • Emphasizing in the public education program the impor- tance of driving defensively and that traffic regulations are meant for the safety of the traveling public. • Prominently displaying safety education materials in businesses and commercial buildings in localities along the LRT alignment that had a high rate of noncompliance with traffic regulations. • Distributing, by location, pamphlets to passing motorists and pedestrians. LACMTA has maintained a very active and aggressive public outreach program, which includes visiting schools, public events, churches, and businesses to give presentations and to distribute safety brochures and DVDs. Public education is also conducted through radio and television advertisements. Metro in Phoenix is trying to boost public awareness and persuade drivers to follow traffic laws before the LRT begins servicing passengers in December 2008. Metro has put together a safety campaign based on a variety of campaigns used by other transit agencies (12). The safety campaign includes the following: • A segment aimed at kids, which is being shared with schools near the transit line; • A DVD that will be widely available and shared with traffic schools; • Adding light rail information in the Arizona driver’s manual and rail questions on the driver’s test; • Increased traffic law enforcement along the Metro line to discourage illegal turns that could result in collisions; • Sending safety brochures to large employers or organi- zations near the track; • Working with professional sports teams to show videos or present other safety information at games; and • Providing information in English and Spanish. State Driver’s License Handbooks The California Driver Handbook addresses LRT safety and specifically calls out the issue of left-turn accidents at intersections (13). The handbook states that, “Light rail vehicles have the same rights and responsibilities on pub- lic roadways as other vehicles. Although everyone must follow the same traffic laws, light rail vehicles, because of their size, require exceptional handling ability” (13, p. 36). It also states 20 Safely share the road with light rail vehicles by: • Being aware of where light rail vehicles operate. Buildings, trees, etc., cause blind spots for the trolley operator. • Never turning in front of an approaching light rail vehicle. • Maintaining a safe distance from the light rail vehicle if it shares a street with vehicular traffic. Looking for approaching light rail vehicles before you turn across the tracks. Complete your turn only if a signal (if installed) indi- cates you may proceed. Light rail vehicles can interrupt traffic signals, so do not pro- ceed until the signal light indicates you may (13, p. 36). In addition, there is a diagram indicating that motorists should not turn left in front of an LRV traveling in the same direction (Figure 24). Other states, including Texas, Colorado, Oregon, and Arizona, have also incorporated LRT education material into their driver’s license manuals. ENFORCEMENT Most accidents appear to be the result of traffic violations and driver error; therefore, there is a need for a strong pro- gram of enforcement of traffic regulations. Enforcement should reduce the frequency of violations and resulting con- flicts and collisions with LRVs (4). Police Presence Assigning police to locations where violations frequently occur will help remind drivers to obey traffic regulations. Publicizing the enforcement program will encourage drivers to take traffic regulations more seriously (4). As part of a demonstration project in the mid-1990s, LACMTA assigned sheriff’s deputies to enforce grade crossing safety along the FIGURE 24 Diagram from California Driver Handbook (Source: California Department of Motor Vehicles 2008).

21 conducted traffic enforcement operations and distributed safety tip handouts to both motorists and pedestrians. LACMTA organized the multi-jurisdictional committee of law enforce- ment. Although the primary thrust of the operation was safety education, law enforcement did issue citations to members of the public who flagrantly violated traffic safety rules (14). Photo Enforcement In an effort to reduce risky behaviors such as driving around crossing gates and running red lights, LACMTA has success- fully used photo enforcement at both gated and non-gated crossings. Along the Metro Blue Line, LACMTA uses photo enforcement to cite drivers for running red left-turn arrows and, as a result, accidents caused by motorists making illegal left turns have been reduced by 62% since left-turn enforce- ment began in 2004 (15) (Figure 25). OTHER Lower Train Speeds TriMet began operation of their MAX Yellow Line in May 2004 with trains operating at 30 mph, as opposed to 35 mph. Although they originally had plans to raise the speed to 35 mph, they have not yet seen a reason to do so. In more than 3 years of operation, they have only experienced 11 left-turn collisions, which have been widely distributed across the many crossings along the corridor, and are believed to be the result of in part to the lower operating speeds. Train-Mounted Cameras Several agencies, including Houston METRO, Sacramento RT, and LACMTA have train-mounted cameras that are positioned outward. Figure 26 shows Sacramento RT’s train-mounted FIGURE 25 Photo enforcement camera (Courtesy: Los Angeles County MTA). FIGURE 26 Sacramento RT’s train-mounted camera (left) and view from camera (right) (Courtesy: Sacramento Regional Transit District). Metro Blue Line, and they continue their police presence today. Law enforcement in Los Angeles coordinated a joint Safety Awareness and Enforcement Operation at some of the busiest Metro Blue Line rail crossings to take place on a weekday morning. Deputies from Metro Transit Services Bureau, the Los Angeles Police Department, the Long Beach Police Department, and Los Angeles County Sheriff’s Department

22 FIGURE 27 Houston METRO’s train-mounted camera (left) and view from camera (right) (Courtesy: Houston METRO). camera. In the photograph on the left, the camera is posi- tioned in the center of the front windshield of the train just above the windshield wiper. The photograph on the right shows the view captured by the camera from the train. Fig- ure 27 shows Houston METRO’s train-mounted camera. In the photograph on the left, the camera is positioned on the exterior front-right of the train. The photograph on the right shows the view captured by the camera from the train. These cameras have been helpful in reviewing collisions to deter- mine causes, which can in turn help agencies identify appro- priate mitigation strategies to reduce collisions. Light Rail Vehicle Operator Defensive Driving Although LRVs cannot be steered like motor vehicles and have a much greater stopping distance than motor vehicles, several transit agencies have incorporated the concepts of motor vehicle defensive driving as part of their new and recur- rent operator instruction. The concepts focus on LRV opera- tors maintaining an awareness of their surroundings through looking well ahead of the LRV’s direction of travel, by scan- ning from curb face to curb face, and continuous movement of the eyes. Standardized Crossings TCRP Report 17 recommends that LRT crossings be standard- ized throughout the system (1). Coifman and Bertini (3) point out that at many LRT crossings the traffic signal is the only con- trol device to keep drivers out of harm’s way. Therefore, every effort should be made to standardize LRT crossings throughout LRT systems, and if possible, between LRT systems.

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TRB's Transit Cooperative Research Program (TCRP) Synthesis 79: Light Rail Vehicle Collisions with Vehicles at Signalized Intersections explores mitigation methods tested and used by transit agencies to reduce collisions between light rail vehicles (LRVs) and motor vehicles where light rail transit (LRT) runs through or adjacent to highway intersections controlled by conventional traffic signals.

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