Raised Medians:
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Medians are raised barriers in the center portion of the street or roadway
that can serve as a place of refuge for pedestrians who cross a street
midblock or at an intersection location. They may provide space for trees
and other landscaping that, in turn, can help change the character of
a street and reduce speeds. They also have benefits for motorist safety
when they replace 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 may not be 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.1
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Manage motor vehicle traffic and provide comfortable left-hand turning
pockets with fewer or narrower lanes.
Provide a refuge for pedestrians crossing the street.
Provide space for street trees and other landscaping. |
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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. |
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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. |
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Adapted from Making Streets That Work, Seattle, 1996
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