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19 remove the anticipation of making the left turn by allowing near and far sides of the stop bar can also be used to increase protected left turns at the end of the through green phase, rather the visibility of the stop bar (4). 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. Crosshatch Pavement Markings Some agencies have implemented crosshatch pavement mark- Light Rail Vehicle "Queue Jump" or "Head Start" ings at intersections to mitigate collisions between LRVs and motor vehicles. Crosshatch pavement markings are used An LRV queue jump can be accomplished by giving LRVs a to designate an area on the pavement where motor vehicles brief head start of 2 to 4 s before motor vehicle traffic after a should not be stopped, such as on approaches to LRT tracks red signal. This head start helps establish LRV presence at where drivers have a tendency to encroach on the tracks. intersections and was recommended to Houston METRO to help prevent illegal left turns in front of LRVs (4). Lane-Use Markings (Arrows) Signal Pre-Emption Phasing Where motorists make left turns from the wrong lane, lane-use markings can be placed in individual lanes on the approach Transit priority that skips a normal signal phase can catch to the intersections. By providing markings on the pavement, drivers by surprise. If possible, the normal sequence of signal drivers are more likely to see them. Markings should be placed phases should not be disrupted (3). This can be accomplished so that they are not concealed by the first one or two vehicles by returning to the phase that was pre-empted by the LRV. in the queue. The lane-use arrows can be supplemented with the word ONLY when only one movement is permitted from the lane (4). PAVEMENT MARKINGS AND/OR TREATMENTS Contrasting Pavement Treatments Extending or Repositioning Pavement Treatments and Markings Contrasting pavement treatments include colored concrete, brick, etc. (Figure 23). They are used to improve the con- To keep right-turning motorists from crossing the stop bar and spicuity of the tracks and to delineate the dynamic envelope of encroaching into the dynamic envelope of the train, RTD in the train. Along the Metro Blue Line in Los Angeles, at loca- Denver extended the concrete apron of the train 8 ft into the tions with side-running operation, drivers on the cross-street right-turn lane, moved the stop bar 5 ft further upstream (from approach to the intersection encroach into the dynamic enve- 15 ft to 20 ft), and applied new pavement markings. As a result lope of the train. To keep drivers back, LACMTA enhanced of the treatments, risky behaviors by motorists decreased the crosswalk before the tracks to make it more noticeable by significantly (7). using a colored concrete pattern. Contrasting pavements on the 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- FIGURE 23 Contrasting pavement treatment in Houston ties where the public may not be familiar with LRT opera- (Courtesy: Houston METRO). tions (4) and, according to Coifman and Bertini (3, p. 10), "An