NYMTC Regional Pedestrian Safety Study - New York Metropolitan ...

The channelization by splitter islands (see Figure 5.8) improves pedestrian safety further by
providing a pedestrian refuge between traffic traveling in different directions. With the splitter
islands, pedestrians can cross the intersection in two stages and need to pay attention to vehicles
approaching from only one direction at a time.
Pedestrian crossings are uncontrolled, and
therefore might be a safety concern if not
well designed. The design should include
splitter islands, which deflect approaching
vehicles and thereby slow them and which
ensure that the pedestrian has to watch for
traffic approaching from one direction only.
The crosswalk should also be recessed so
approaching vehicles watching for traffic that
is in the circle are not in conflict with
crossing pedestrians. A Dutch study of 181
intersections that were converted to
roundabouts found a reduction in all types of
crashes of 51 percent. The reduction in
pedestrian crashes was 73 percent and in
pedestrian injury crashes was 89 percent.
(Robinson et al., 2000)
Figure 5.10 Roundabout in Suffolk County
The public’s reaction to plans for implementing roundabouts has been negative, perhaps due to
memories of the earlier rotaries. However, a survey by NYSDOT indicates that after drivers
have experienced the roundabouts they are more accepting. See Table 5.2 below.
Table 5.2 NYSDOT Survey of Public Acceptance of Roundabouts
Public Acceptance
Low Moderate High
Before Construction 29% 59% 12%
After Construction 3% 42% 55%
Source: A Citizen’s Guide to Roundabouts, NYSDOT, 2004B.
Neighborhood Traffic Circles: Neighborhood traffic circles (sometimes called mini-circles)
also require traffic generally to circulate counterclockwise around a center island, but in contrast
to roundabouts, they do not have yield control at the entrance or splitter islands. They are
typically used in very low volume, residential locations. The radius of the center island is
frequently tight, making circulation by large vehicles difficult; one solution is to use mountable
curbs on the center island. Additionally, large vehicles may be allowed to turn left in front of the
center circle (that is, circulate clockwise). Seattle found a 90 percent reduction in crashes of all
types with neighborhood traffic circles. (Harkey and Zegeer, 2004)
Narrowings: There are two types of narrowings, center island narrowings and roadway
narrowings. Center island narrowings are used as gateways to residential and/or business areas.
NYMTC Pedestrian Safety Study 68