Sidewalk Expansion

Usage: Limited

A sidewalk expansion involves widening the sidewalk over a full block, typically extending across multiple blocks along a corridor, often requiring Lane Removal or consolidation to create additional pedestrian space. Many corridors experience a high volume of foot traffic, but the existing sidewalks are too narrow to comfortably accommodate these trips. Sidewalk Expansions have been implemented through DOT’s “Super Sidewalk” Operational Projects, such as the 2022 initiative on 9th Avenue using Color Surface Treatments and flexible delineators to define pedestrian zones along the curb.

Once completed, a sidewalk expansion is considered a Full Sidewalk, with expanded pedestrian space and a furnishing zone along the new curb line.
 

9th Avenue, Manhattan
8th Avenue, Manhattan

Benefits

  • Review benefits for Curb Extension
  • Provides additional pedestrian space, alleviating overcrowding and significantly enhancing safety and comfort in areas where existing sidewalks are insufficient to accommodate high foot traffic.
  • Expanding sidewalk space improves pedestrian comfort and convenience, supporting an increase in walking trips and enhancing overall mobility
  • Provides opportunities for greening and other amenities within the furnishing zone, enriching the pedestrian experience and contributing to a more vibrant and active streetscape
     

Considerations

  • Sidewalk expansions must consider various constraints such as drainage, grading, utility infrastructure, and traffic impacts, which may limit their feasibility and usage
  • A traffic study may be required to assess the impacts of sidewalk expansion, particularly when lane removal is necessary
  • A modal share analysis may be useful to evaluate the distribution of trips by different transportation modes, such as walking, micromobility, public transit, or vehicle
  • When expanding an existing sidewalk, plan for the relocation of amenities in the current furnishing zone, such as fire hydrants, street furniture, and light poles. While many elements can be moved to the new curb line, street trees must remain in place. The design should thoughtfully integrate the existing placement of street trees, ensuring they remain undisturbed and are well-incorporated into the expanded sidewalk layout. Review Tree Beds
  • Consider access at the curb and dynamic uses. Review Curb Management
  • While limited and typically as part of new development, consider opportunities for widening the sidewalk within private property; review Department of City Planning Sidewalk Widening zoning provisions 
  • In areas where sidewalk expansions are not feasible, consider Curb Extension and Mid-Block Narrowing
     

Application

  • Sidewalk Expansions are ideal for corridors with heavy pedestrian traffic, such as areas near transit hubs, commercial districts, and other high-activity areas
  • DOT has implemented Sidewalk Expansions in multiple locations as “Super Sidewalks” through Color Surface Treatments and flexible delineators
     

Design

  • Review Full Sidewalk
  • Sidewalks should be as wide as possible appropriate to foot traffic and available street width. Review Pedestrian Mobility Plan
  • Must be designed to maintain positive drainage from the building, drainage of stormwater from the gutter, and not cause ponding; depending on site-specific grading conditions, this might include properly locating or relocating catch basins
  • In challenging grading locations, consider use of a trench drain where maintenance can be provided
  • Sidewalk expansions must conform to ADA requirements for a minimum clear-path width and provision of spaces where wheelchair users can pass one another or turn around
  • Install new pedestrian ramps per DOT standards; review Pedestrian Ramps
  • Review Sidewalks for information on options for sidewalk materials
  • Relocate street lights and signal infrastructure to the new curb per DOT standards; may require a lighting study to determine the appropriate number and location of poles given the widened sidewalk. Review Lighting Chapter
  • Relocate street furniture as appropriate; review Furnishings Chapter for siting guidelines and requirements. The area within 18 inches of the curb should be kept free of all obstructions
  • Preserve existing trees in place – review Tree Preservation and Protection. Consider planting new or additional trees at the expanded curb line; review Tree Beds
  • For “Super Sidewalks”, edge objects like planters, granite blocks, and flexible delineators should be placed around painted curb extensions and marked pedestrian areas to create a clear boundary, buffer them from travel lanes, and enhance visibility for pedestrians, including those with vision impairments