D . Curb Ramps
Curb ramps are important devices at intersections because they facilitate crossing for wheelchair users , people pushing strollers , bicyclists , and others . Curb ramps provide transition areas from street to sidewalk where a raised curb is located ( Figure 7.41.5 ).
Design Criteria :
• The curb ramp must meet American with Disabilities Act ( ADA ) standards .
• The minimum width for exterior ramps is 5 feet .
• A minimum of 4 feet ( 5 feet preferred ) should be provided at the top of the ramp for turning or bypassing the ramp .
• Ramp and approaches shall be clear of obstacles , such as fire hydrants , poles , and inlets .
• A level landing area should be provided at both ends of the curb ramp to provide a resting zone for users .
• The low end of the ramp or curb cut should meet the grade of the street with a smooth transition .
• Curb ramps shall be provided at channelization islands in an intersection and median refuge island , unless the full cut through openings are provided at grade with the street .
• Curb ramp surfaces should be textured to meet ADA standards and to prevent slippage ( Figure 7.41.6 ).
• Provide detectable warning pavement or
Figure 7.41.5 . The curb ramps below are aligned with the marked crosswalk and are ideally perpendicular to the roadway
Figure 7.41.6 . The curb ramp with detectable warning strip at intersection .
pavers ( truncated dome ) at the bottom of the ramp .
• Good drainage at intersection corners is important so that standing water does not accumulate within the crossing area .
• Storm drainage inlets should be placed on the uphill side of the crosswalks and outside the crosswalk area .
E . Islands and Refuges
Pedestrian refuge islands are typically raised islands located along the centerline of a street . They are typically constructed at wide intersections with several travel lanes and turn lanes . Refuge islands allow pedestrians to cross fewer lanes at one time and should be wide enough to hold several pedestrians at once ( Figures 7.41.7 and 7.41.8 ).
Design Criteria :
• Refuge islands should be a minimum of t least 6 feet wide ( preferably 8 feet ).
• An area should be provided for accessible pedestrian push-buttons .
• Vehicular and pedestrian visibility should be maintained if landscape enhancements are provided in the refuge area .
• On narrow islands ( 6 feet wide ) bollards should be installed for added protection for waiting pedestrians .
• For narrow refuge islands , at-grade cuts are needed for wheelchair access .
• For wider islands , curb ramps with level landings are needed .
• Refuge islands are best applied on wide streets ( four or more lanes ) with moderate
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