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LIGHT RAIL VEHICLE COLLISIONS WITH VEHICLES AT SIGNALIZED INTERSECTIONS SUMMARY At their start-up, new light rail transit (LRT) operating systems typically experience undesir- able frequencies of light rail vehicle (LRV)motor vehicle collisions, particularly where motor vehicles cross LRT tracks located in or adjacent to highway intersections that are con- trolled by conventional traffic signals (i.e., street-running operations). Over time, as agencies have gained experience with LRT operations, they have addressed the problems through engineering, education, and enforcement efforts. This report is a synthesis of today's state of the practice with regard to mitigating collisions between LRVs and motor vehicles at signal- ized intersections. This synthesis will help transit agencies to better understand, and to learn from, the experiences of other agencies facing similar challenges. The objective of this study was to report on the mitigation methods tested and used by tran- sit agencies to reduce collisions between LRVs and motor vehicles where LRT runs through or adjacent to highway intersections controlled by conventional traffic signals, with a particular focus on collisions occurring between LRVs and vehicles making left turns at intersections. This synthesis includes success stories and specific actions taken to achieve positive results, as well as examples of unsuccessful actions. The issues addressed include a range of LRT opera- tions and environments (median-running, side-running, contra-flow, and mixed-use LRT align- ments), urban and suburban settings, and a variety of U.S. geographic regions. As directed by the topic panel, the technical approach for this synthesis project included a review of recent relevant literature as well as structured telephone interviews with the fol- lowing transit agencies: Tri-County Metropolitan Transportation District of Oregon (TriMet)--Portland, Oregon; Denver Regional Transportation District (RTD); Metropolitan Transit Authority of Harris County (METRO)--Houston, Texas; Los Angeles County Metropolitan Transportation Authority (LACMTA); New Jersey Transit--HudsonBergen Light Rail; Sacramento Regional Transit District (RT); and Dallas Area Rapid Transit (DART). A review of the most recent literature and structured interviews with these transit agencies revealed that collision types and circumstances vary between agencies, depending on a variety of factors. However, transit agencies with LRT systems consistently reported that most colli- sions between LRVs and motor vehicles are caused by motorists making illegal or improper turns or running red lights. The most common scenarios of left-turn and right-angle collisions at signalized intersections have been categorized as the following: Motorists in left-turn pocket lanes violate the red left-turn signal indication and collide with LRVs approaching from behind. Motorists make illegal left turns against static no left-turn signs (at locations where turns are prohibited) and collide with LRVs approaching from behind. Motorists violate active turn-prohibition signs and train-approaching warning signs in conflict with LRV operation (at locations where turns are permitted or prohibited).

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2 Motorists make left turns from adjacent through-only lanes instead of from the lanes shared with the LRVs (mixed-use alignment). Drivers encroach on or stop on the tracks and are struck by an LRV (coming from either direction) at a right angle (side-running alignment only). Drivers run a red signal indication and collide with an LRV (coming from either direc- tion) at a right angle. Transit agencies have taken a number of approaches and have implemented a variety of countermeasures to mitigate collisions between LRVs and motor vehicles at signalized inter- sections. These countermeasures include physical barriers, traffic signs, signal displays, traffic signal phasing, pavement markings and/or treatments, public outreach and/or education, police and photo enforcement, and others such as lower train speeds, standardized crossings, and LRV operator defensive driving. This synthesis report describes 34 countermeasures and presents case studies of recent applications of many of the countermeasures by transit agencies. Although some of these countermeasures have been more effective than others, there have been few empirical studies conducted to examine the effectiveness of the coun- termeasures in terms of reducing the frequency and severity of collisions. Despite the efforts put forth by transit agencies and city and county traffic engineering departments, collisions between LRVs and motor vehicles at signalized intersections continue to occur, and agencies continue to seek out innovative countermeasures in an effort to further reduce the frequency and severity of these collisions.