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Intersections and Mid-Block Crossings
Transit Signal Priority (TSP) is a powerful method which allows for modification of signal timing for transit vehicles. Note that this is different from preemption (commonly used for rail applications or emergency vehicles). TSP can be used to shorten a red phase or lengthen a green phase to accommodate an approaching transit vehicle. This accommodation can be applied to all approaching transit vehicles or only to those running behind schedule. WARRANTS The Federal Highway Administration’s (FHWA) Manual on Uniform Traffic Control Devices for Streets and Highways (MUTCD) provides standards and guidance for the application of all allowed traffic control devices including roadway markings, traffic signs, and signals. For example, stop signs and traffic signals are expected to meet minimum thresholds before application. A warrant is the threshold that includes the criteria such as number of vehicles, number of pedestrians or other users, distance to other devices, crash history, and more. These warrants are often viewed as preventing local transportation professionals from applying devices that, in their opinion, may improve safety. For example, trail and/or pedestrian crossings of busy, high-speed, wide arterial streets may need signals for user safety, but signals may not meet the MUTCD warrants. The MUTCD suggests that strict adherence to the warrants is not the only factor to evaluate when considering whether a traffic control device is justified. The warrants are a component of a broader engineering investigation and are not a substitute for engineering judgment. The MUTCD lists the satisfying conditions of a warrant as “guidance” for implementing an approved traffic control device. Guidance is defined in Section 1A.13 of the 2009 MUTCD as “a statement of recommended, but not mandatory, practice in typical situations, with deviations allowed if engineering judgment or engineering study indicates the deviation to be appropriate.” The MUTCD typically uses the verb “should” for guidance conditions, as differentiated from the verb “shall” for standards. To use some desirable traffic control devices as prescribed by Complete Streets best practices, it may be necessary to establish local warrants or modify those provided in the MUTCD to suit the Context Based Classification and Typologies. In special circumstances that deviate from the warrants, reasons for the variation must be documented. For example, Hillsborough County may establish that trail crossings, school crossings, or bus stop locations qualify for certain traffic control devices (traffic signals, pedestrian hybrid beacons, crosswalks, etc.) and treatments without meeting the warrants. Another example would be the installation of additional traffic signals to break up long stretches of corridor to manage speed through better signal coordination, increasing connectivity between neighborhoods, and providing improved crossings for vulnerable users. Bicycle Intersection Treatments People riding bikes are particularly vulnerable at intersections. Markings and facilities for bikes can be placed in intersections to increase rider comfort and increase driver awareness and anticipation of potential conflict points. The following treatments are summarized to provide an overview of treatments available. Further guidance on the use of these treatments is available in the NACTO Urban Bikeway Design Guide, Second Edition.
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