Many narrow or crowded down town streets operate informally as shared streets during rush hour or at lunchtime, but are not regulated as such. A commercial shared street environment should be considered in places where pedestrian activity is high and vehicle volumes are either low or discouraged. Commercial shared streets can be designed for narrow or wide cross sections, but become increasingly complex and difficult to maintain as a shared space as width increases.
From 1960–80, many neighborhood main streets and downtown retail corridors were converted to pedestrian-only usage. These conversions were often called “pedestrian malls.” In an era of declining downtown retail revenues due to competition from shopping center developments outside of historic cores, many of these conversions were unsuccessful or suffered from poor maintenance and a lack of programming or policing.1
Commercial shared streets differ from this earlier generation of pedestrian malls in both their regulation and implementation. Shared streets maintain access for vehicles operating at low speeds and are designed to permit easy loading and unloading for trucks at designated hours. They are designed to implicitly slow traffic speeds using pedestrian volumes, design, and other cues to slow or divert traffic.
Existing Conditions
The street in the rendering above is a common sight in many older cities where downtown commercial streets may predate wider grid streets. In newer cities, a retail district with heavy parking utilization and narrow, congested sidewalks may have similar conditions or opportunities.
1Sidewalk congestion creates unsafe conditions, as crowding forces some pedestrians to walk in the street to avoid crowds.
Vehicles in search of on-street parking create traffic congestion.
2Loading and unloading trucks obstruct pedestrian and vehicle traffic. Truck drivers park on the side walk to preserve vehicle flow while unloading, forcing pedestrians to mix with motorists.
Recommendations
The street illustrated above depicts a 22-foot shared way within a 30-foot right-of-way.
3Textured or pervious pavements that are flush with the curb reinforce the pedestrian-priority operation of the street and delineate a non-linear path of travel or narrow carriageway. Special pavements, especially unit pavers, may be subject to additional maintenance costs and should be selected based on regional climate and long-term durability. Selection of snowplow-compatible materials is recommended for colder climates. Drainage channels should be provided either at the center of the street or along the flush curb, depending on existing conditions and the overall street width. Drainage channels are often used to define the traveled way from the clear path.2
4Commercial shared streets should be accessible by single unit trucks making deliveries. Where commercial alleys are non-existent, it may be advantageous to design a shared street to accommodate large trucks, though significant changes to the design should be avoided. Designated loading and unloading zones may be defined through differences in pavement pattern or use of striping and signage.
5Street furniture, including bollards, benches, planters, street lights, sculptures, trees, and bicycle parking, may be sited to provide definition for a shared space, subtly delineating the traveled way from the pedestrian-exclusive area.
Shared streets may be closed to through traffic for specific portions of the day. Use movable planters and time-of-day restrictions to regulate the shared space.
Provide tactile warning strips at the entrance to all shared spaces. Warning strips should span the entire intersection crossing.
Prior to the application of a shared street, cities are encouraged to experiment with car-free hours or to test a conversion using temporary materials to evaluate the potential impact on traffic operations.
Commercial shared streets restrict transit access. For pedestrian streets that provide direct transit access, consider the application of a transit mall.3
Depending on the overall street width, designers may consider providing a 3–5-foot-clear path protected from
traffic. The clear path should be defined using planters, bollards, and street furniture, as well as detectable
warning strips or textured pavers. For narrower shared streets and alleys, use of a clear path is discouraged.
Shared streets should be designed so that people walk comfortably and naturally within the roadway.
Street furniture helps define the shared space.
- The first pedestrian-only outdoor mall opened in Kalamazoo, MI, in 1959. For case studies of early pedestrian malls, see:
Roberto Brambilla and Gianni Longo, For Pedestrians Only: Planning, Design, and Management of Traffic-free Zones, (New York: Whitney Library of Design, 1977). ↩︎ - The San Francisco Better Streets Plan provides guidance on “channels” and “runnels” that may be suitable for center street drainage.
“Channels and Runnels,” San Francisco Better Streets: A Guide to Making Street Improvements in San Francisco, accessed May 21, 2013, http://www.sfbetterstreets.org/find-project-types/greening-and-stormwater-management/stormwater-overview/channels-and-runnels/. ↩︎ - “Transit Mall Case Studies,” (San Francisco County Transportation Authority). ↩︎