Raised Speed Reducer

Usage: Wide

A raised area of a roadway that deflects both the wheels and frame of a traversing vehicle with the purpose of reducing vehicle speeds. The two basic types of raised speed reducers are speed humps and speed cushions. Both are typically raised 3 to 4 inches above the level of the roadway, and both have a proven speed-reducing track record in New York City. While speed humps span the width of the street, a speed cushion is divided into narrow segments, so that vehicles with wider wheel bases (buses, emergency vehicles, large trucks) are not affected.

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Sterling Place, Brooklyn


  • Compels drivers to travel at speeds no higher than the street’s design speed


  • Speed humps may impact emergency vehicle movement
  • May generate additional noise


  • May be requested by the public, Community Boards, or elected officials with approval based upon speed, crash, street-geometry, and street-operations criteria
  • Speed humps are not appropriate on "local" or "through" truck routes or MTA bus routes, emergency vehicle response routes, or street blocks with FDNY houses or hospitals located on them
  • Neither speed humps nor speed cushions are appropriate on streets with more than one moving lane per direction
  • School locations are given priority


  • Space raised speed reducers to maintain desired operating speeds
  • Appropriate warning signs and roadway markings should accompany raised speed reducers
  • Locate raised speed reducers in the middle of the roadway, with the gutters kept clear for proper road drainage
  • Use signage or other methods to alert operators of snow-clearing vehicles to the presence of raised speed reducers
  • While raised speed reducers are an effective method to retrofit streets to reduce motor vehicle speeds in lieu of street reconstruction, all reconstructed streets should be designed to achieve desired speeds, e.g., using appropriate roadway width and alignment, horizontal deflection, traffic controls, trees, and other traffic calming treatments
  • Utilize recycled content in paving materials