Raised Medians

This median provides a refuge for pedestrian while added safety and aesthetic value to the roadway.

Medians are raised barriers in the center portion of the street or roadway that can serve as a landing place for pedestrians who cross a street midblock or at an intersection location. They may provide space for trees and other landscaping. They also have benefits for motorist safety when they replace continuous center turn lanes. Desired turning movements need to be carefully provided so that motorists are not forced to travel on inappropriate routes, such as residential streets, or make unsafe U-turns.

Continuous medians are not the most appropriate treatment in every situation. In some cases, separating opposing traffic flow and eliminating left-turn friction can increase traffic speeds by decreasing the perceived friction of the roadway. They may also take up space that can be better used for wider sidewalks, bicycle lanes, landscaping buffer strips, or on-street parking and may cause problems for emergency vehicles. In some environments, medians can be constructed in sections, creating an intermittent rather than continuous median. Another good alternative device for two-, three- or four-lane roads is the crossing island, which provides a crossing refuge for pedestrians and, in some designs, aids in decreasing vehicle speeds.

Raised medians are most useful on high-volume, high-speed roads, and they should be designed to provide tactile cues for pedestrians with visual impairments to indicate the border between the pedestrian refuge area and the motorized vehicle roadway. Examples of good and bad designs for raised median crossings can be found in Chapter 8 of Designing Sidewalks and Trails for Access: Part II of II: Best Practices Design Guide.

Purpose

  • Manage motor vehicle traffic and provide comfortable left-hand turning pockets with fewer or narrower lanes
  • Provide a landing for pedestrians crossing the street
  • Provide space for street trees and other landscaping

Considerations

  • Ensure that there is enough room for wider sidewalks, bike lanes, and planting strips before proceeding with construction.
  • Landscaping in medians should not obstruct the visibility between pedestrians and approaching motorists.
  • Median crossings at midblock and intersection locations must be fully accessible by means of ramps or cut-throughs, with detectable warnings.

Estimated cost

The cost for adding a raised median is approximately $15,000 to $30,000 per 30 m ($15,000 to $30,000 per 100 ft), depending on the design, site conditions, and whether the median can be added as part of a utility improvement or other street construction project.