D . Chokers
Chokers , also commonly known as bulb outs , curb extensions , or neck downs , are typically installed at curb radii . By adding chokers to curb radii , they reduce distance for pedestrians to cross streets . By reducing the distance to cross a street , pedestrian safety and vehicle movement improves ( Figure 7.9.12 and 7.9.13 ).
Chokers can be used on one side of a one-way street radius and at mid-block crossings where pedestrian traffic is high , such as in downtowns or Main Streets . They can be used at intersections to create a one-way entry or exit point for that specific street alignment .
Chokers are best used where on-street parking is dominant . When chokers are used in conjunction with landscape treatments they can enhance the street and buffer adjacent parking . Chokers help to identify mid-block crossing locations for motorists . They can be used at intersections with high volumes of traffic and significant numbers of crossings , or on minor access roads and local residential streets where there is insufficient time to cross the street .
Design Criteria :
• Maintain pedestrians ’ and motorists ’ visibility .
• Provide appropriate traffic signage and traffic signals at intersections and midblock crossings .
• Provide lighting ( street-level or pedestrianlevel ) and marked crosswalks to enhance pedestrian visibility for mid-block crossings .
• Provide adequate radius for intersections and vehicular turning movement .
• Provide median and refuge islands when the length of the crossing exceeds 33 feet or with three or more travel lanes .
• Evaluate storm drainage and utility locations prior to design and installation of chokers , curb extensions , or bulb outs .
• Provide low growing landscape and plant material in islands .
Figure 7.9.12 . Site plan of choker traffic calming device .
Figure 7.9.13 . Choker enlargement detail .
Chapter 7 : Design Guidelines | 7-81