Intersections are the most complex roadway facilities, with turn lanes, pedestrian crossings, transit stops, signage, signals, and other elements all concentrated in one location. Multiple travel movements and modes all must share a limited area; the land value associated with the access and visibility of corner properties adds another dimension. However, vehicle-related design considerations alone generally determine intersection geometry, and accommodating cars and trucks often comes at the expense of other travel modes. For example, designing intersections for large vehicle- and/or higher-speed turning movements limits the potential to provide pedestrian refuges, small radius corners, bus stop bulb-outs, bike lanes, and other multimodal facilities.
Local communities and agencies should evaluate the function of an intersection relative to the full range of travel modes as well as frontage land use. The appropriate design vehicle should be used to support multimodal travel through intersections. For example, in node area intersections with high levels of pedestrian and/or transit transfer activity, corners should have the minimum radius feasible in order to reduce vehicle-turning speeds, shorten crosswalk distances, and to maximize bus stop waiting area. Dual left turn lanes should be eliminated to accommodate pedestrian refuges where possible, with longer stacking turn lanes and/or modified signal timing employed instead. Building setbacks should be considered to create additional sidewalk space and visibility of first floor businesses. Figures 5-5a through 5-5d depict the various intersection configuration possibilities for the GBI corridor.
