Synthesis of Safety for Traffic Operations - Transports Canada

Synthesis of Safety for Traffic Operations March 2003
The residual or carryover effects of these treatments were assessed one week after
removal; the results are in Table 8.13.
TABLE 8.13: Mean Speed Effects of Speed Display Boards after Removal
Treatment
Reduction in Mean Speed (km/h)
Along side Downstream
Board Only 2.7 1.0
Board + Enforcement 0.3 1.0
Curbside Parking
Main (1984)
Main (1984) undertook a before-after analysis of collision rates on a sampling of arterial
streets in the City of Hamilton, Ontario, to assess the safety impacts of curbside parking
prohibitions. The parking prohibitions were full-time and generally accompanied by a
stopping prohibition during the weekday morning and afternoon peak travel periods. Site
selection was intended to be representative of the entire system, with all sites in areas that
were fully developed.
The results of the safety analysis are shown in Table 8.14. The total number of collisions
do not include collisions at signalized intersections. All six of the road sections under
analysis displayed a reduction in the collision rate, with an average reduction of 37% or a
CMF of 0.63.
TABLE 8.14: Safety Effects of Prohibiting Curbside Parking
Section Length
Year
Before
After
Implemented # AWDT Rate # AWDT Rate
CMF
1 1.03 1969 19 3660 4.8 9 3860 2.2 0.46
2 0.75 1969 38 4410 11.0 19 4610 5.2 0.47
3 1.71 1968/9 76 7850 5.4 58 9600 3.4 0.63
4 0.43 1975 40 20560 4.3 30 21600 3.1 0.72
5 0.84 1973 76 16180 5.3 62 18910 3.7 0.70
6 1.90 1970 477 20180 11.9 463 24370 9.5 0.80
Average 0.63
McCoy et al (1990)
McCoy et al (1990) using an extensive dataset from the Nebraska highway system
investigated the relative safety of different types of curbside parking (i.e., parallel, lowangle
and high-angle parking). The study employed a cross-sectional study design with
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