Pedestrian Signal Safety - AAA Foundation for Traffic Safety

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For the major street approaches, there was no change in LOS (LOS C remained the same) for all
volume groups and pedestrian walking speed scenarios analyzed. The increase in ADPV under
existing volume conditions as compared to a modeled increase of 15 percent above existing volumes
for the 3.00 ft./sec., 3.50 ft./sec., and 4.00 ft./sec. pedestrian walking speeds was 4, 3, and 2 sec.,
respectively. The lowest delay value modeled was 23 sec. and the highest delay value modeled was
29 sec.
For the minor street approaches, delays decreased as walking speeds decreased because the traffic
along the minor street approaches required less green time than the pedestrian clearance time.
LOS ranged from LOS B to LOS C for each of the volume and pedestrian walking speed scenarios
analyzed. The range in ADPV under existing volume conditions as compared to a modeled increase
of 15 percent above existing volumes irrespective of the walking speed assumption was 20 sec. to 24
sec.
Table G-12. Salt Lake City, Utah intersection characteristics: approach lane usage, peak-hour traffic
volumes, and cycle length.
Approach
Northbound
(MJ)
Southbound
(MJ)
Eastbound
(MN)
Westbound
(MN)
MJ
approach
MN
approach
Number of approach lanes
L LT T TR R Total
-10
percent
Existing
Peak-hour tra ffic vol umes
(existing and m odeled)
+5
percent
+10
percent
+15
percent
1 0 3 0 1 5 964 1,071 1,125 1,178 1,232
1 0 3 0 1 5 428 476 500 524 547
1 0 1 1 0 3 362 402 422 442 462
1 0 2 1 0 4 497 552 580 607 635
2 0 6 0 2 10 1,392 1,547 1,624 1,702 1,779
2 0 3 2 0 7 859 954 1,002 1,049 1,097
Total 4 0 9 2 2 17 2,251 2,501 2,626 2,751 2,876
Cycle len gth: 120 sec.
* Note: L = left; LT = left-through; T = through; TR = through-right; R = right.
Vol ume
range
1,392 –
1,779
859 –
1,097
2,251 –
2,876