Transit may be configured to operate in completely separated running ways at the sides of urban boulevards. Side transitways may operate either uni-directional or bi-directional service on one side of the street.
Side transitways maintain the enhanced capacity and flow of fully separated transitways while enabling pedestrians to board directly from the sidewalk. They may also create enhanced boarding areas and buffer active users from vehicle traffic.
Used with high-quality, frequent bus or rail service, especially on one-way streets.
May be applicable in contexts with few crossings or driveways (such as waterfronts or natural boundaries).
Bike facilities, including raised cycle tracks, can be simultaneously implemented and aligned with transit operations.
Where right-side boarding is required, such as for BRT services that also operate in curbside lanes.
Placing the transitway in dedicated, separated space improves travel times by reducing conflicts with parked cars, bicycles, and some turning movements.
Side-running transitways can serve transit with potentially very high capacity and frequency, while improving the pedestrian and passenger experience of the street.
Compared to central median transitways, side transitways can reduce conflicts associated with pedestrian crossings and turning traffic, especially in edgefront conditions.
Turns across the transitway must be managed, and sometimes prohibited. Prohibiting right turns requires more guidance than left-turn prohibitions.
Transitway must be physically separated from travel lanes either by grade differences or vertical elements.
All intersections with pedestrian, bicycle, or motor vehicle traffic must be signalized. To avoid conflicts with transit vehicles, left- and right-turning traffic across the transitway must be either prohibited or accommodated using turn lanes with dedicated signal phases.
When headways are long enough to prevent turning vehicles from blocking the transitway, either a lateral offset between turning vehicles and the transitway, or a dedicated turn lane that crosses the transitway, can be used.
Place signs and design elements (like curbs with tight corner radii) to direct turning traffic from cross streets away from the transitway, and into the proper general traffic lanes.
If parking is located next to a transitway, 4 feet of clear width must be available adjacent to the parking lane to accommodate loading.
Passenger loading zones for accessible parking spaces may require 8 feet of clear width if a ramp is expected to be deployed.
“Ch. R3, Technical Requirements.” Proposed Accessibility Guidelines for Pedestrian Facilities in the Public Right-of-Way. US Access Board, Washington, DC: 2011.
Intersection design should reflect the presence of the transitway to highlight its path and deter conflicting movements. Crossings may be raised to the transitway grade at intersections and driveways, where applicable.
Pavement should be colored to emphasize dedicated lanes and deter drivers from entering them. BUS ONLY (MUTCD 3D-01) or LRT ONLY pavement markings may also be appropriate. Color application may be limited to the intersection approach.
Transitways should be implemented alongside complementary treatments such as all-door boarding, transit signal priority, and level boarding.
Provisions should be made to alert other street users when transit vehicle traffic approaches from unexpected directions.