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32 traffic controls in place, left-turn violations continued to METRO system. To improve traffic operations and to min- occur (21). In an effort to mitigate these left-turn violations imize common types of collisions between LRVs and motor and collisions, in 1999 DART implemented "train coming" vehicles, the following features were incorporated into the signs at the intersections. These signs display an LRV icon and planning, design, and/or construction of the METRO light the text, "Train Coming." The signs illuminate on detection of rail system (24): an LRV from either direction. The signs are placed in the median on a pedestal pole directly across from the left-turn Protected left- and right-turn lanes. Turns across the pocket lane. There is also an additional left-turn signal in tracks will be made only from exclusive (left- or right- this location (21). Since the installation of these signs, the turn-only) turn lanes. "Protected" signals will control number of collisions between LRVs and left-turning motorists left- and right-turn movements by red, amber, and green has been reduced dramatically. arrows, which are considered to be the safest form of turning control used by traffic engineers. Other cities tried using special "No Left-Turn" or "No Right-Turn" VALLEY METRO (PHOENIX) signs in shared lanes that activate when a train is approaching; however, based on discussions with the The 20-mile initial METRO light rail line is scheduled to begin LRT operating systems, these signs were mostly ignored operations in December 2008. The METRO system will oper- by motorists, resulting in accidents. ate at street level in a lane separated from traffic, and trains will Longer left-turn lanes. Left-turn storage bays will travel primarily in the street median. When METRO construc- be lengthened to handle projected 2020 traffic condi- tion is complete, there will be improved light-rail synchro- tions, including storage for the added U-turns that nized signals at 148 intersections. That number includes 15 will be required to access some driveways and local new signals added to create more U-turn areas for business streets. Adequate storage is critical to improving safety access (22). and reducing congestion caused by traffic backing into through-travel lanes. METRO is currently testing LRVs on Washington Street LRV cameras. Cameras will be installed on the Metro between 48th and 56th Streets. During this testing, auto- LRVs so that train operators can better see obscured mobile traffic travels alongside the LRV that is operated at very pedestrians and obstructions. They will also be installed slow speeds (22). METRO is working with residents, schools, on the vehicle exterior for monitoring and recording traf- and businesses in the area to ensure that they all understand fic conditions, unsafe driving behaviors, and accidents. the basics of light rail safety. Beginning December 3, 2007, Controlled track crossings. For safety reasons, traffic will METRO stopped using police officers to guide traffic at inter- be allowed to cross the tracks only at a controlled loca- sections. Instead, both LRVs and automobile traffic are being tion. Green-arrow signal indications for left turns and controlled by METRO's traffic management system. The new U-turns will replace solid-green balls. Special signing, system will control all intersections on Washington Street such as the flashing LRV-activated train-approaching between 44th Street and Priest Drive (23). sign, will be installed. Six-in. curbs. METRO will use 6-in. curbs to separate In the spring of 2008, METRO gradually began expanding and protect traffic from the rail guideway. Some cities its vehicle testing activities. At that time, they began a public use curbs, and others use concrete barriers (e.g., San education campaign on the safety rules for light rail with the Jose), paint (e.g., Salt Lake City), or traffic buttons (e.g., goal of raising the awareness of rail safety and encouraging Houston) to delineate the dynamic envelope of the train. safe behaviors. METRO plans to use the communication New frontage roads. Access on one-way streets will be resources of their partner cities and sought communication maintained for businesses with the use of new 16-ft partnerships with the Valley's businesses, neighborhood frontage roads when needed. Drivers will be able to enter groups, community organizations, and the news media (24). the frontage roads at traffic signals and exit at signalized slip ramps to re-enter the main flow of traffic. New spe- To make it safer and more street-friendly, METRO's light cially designed frontage roads were designed to handle rail design was influenced by discussions with other rail large trucks and emergency access and are necessary to authorities and cities. Observing and researching similar maintain safe business access on the one-way streets. light rail systems around the country proved to be invaluable This is the first design of its kind being used specifically in determining appropriate system enhancements for the for light rail applications in the United States.