Consider the Context
Different activities and users require different treatments. A commercial street, for example, requires more room for pedestrians, cyclists, and transit users than a support street predominantly used for loading or unloading of goods.
One-way streets are best used where streets are laid out in a grid or when there are nearby opposite direction streets to ensure network connectivity. One-way operation is well-suited for narrow streets and alleys where vehicle access is needed but two lanes are not possible. In a well-connected network, one-way streets provide high capacity per lane, freeing up space for non-traffic uses with minimal traffic impact. One-way streets should be used in conjunction with turn and speed management and traffic calming measures such as street and lane narrowing or repurposing excess road width for designated pedestrian, cycle, and transit facilities.
Two-way streets provide increased network connectivity, especially where the street network is irregular, with frequent dead ends, or where there are limited options for continuous travel across long distances.1 Two-way streets provide improved access and tend to reduce local vehicle distance traveled by providing more direct vehicle routes. In places with narrow road width and low vehicle volumes, two-way streets have a traffic calming effect, lowering speeds which reduces crash severity. However, on wider streets or in areas with high vehicle volumes, two-way streets can increase crash frequency due to increased complexity at intersections and turns across oncoming traffic.
Continuous lanes move traffic along a corridor, with turn lanes where necessary. Cities should allocate the number of lanes based on need, not road width. If there is additional width, space should be repurposed for pedestrian, cycle, or transit facilities.
Separate Turn Movements
Separate turn movements where high pedestrian volumes and vehicle turn movements coincide. Use separate turn phases or turn lanes, or move turns to a different intersection with fewer foot crossings. Problematic turns should be consolidated and relocated to areas where the turns can be accommodated.
Use signals and other traffic control elements to reduce long vehicle queues that block pedestrian crossings and cross streets, erode the walking environment, or create the potential for gridlock. Where a large street narrows, or where a highway transitions into a street, use signals to keep queues on the larger street or highway rather than overwhelming the smaller street. When congestion exists along a route operating at capacity, bottlenecks can be moved upstream, creating room for transit, walking, and cycle facilities.
Reducing the volume of traffic that enters a district improves total trip times and reduces the delays for buses in mixed traffic. This reduction can be achieved through pricing, route metering, and volume and access management.