Safe Streets Arlington Plan Safe Streets Arlington Plan | Page 99

Kimley > Horn

60 to 80 %
13
19
34.23
66.95
1.14
2.12
80 to 100 %
20
139
66.95
2277.07
2.12
47.64
Bicycle & Pedestrian HIN
0 to 20 %
0
1
0
6.78
0
0.6
20 to 40 %
2
4
6.78
10.86
0.6
0.96
40 to 60 %
5
12
10.86
16.05
0.96
1.36
60 to 80 %
13
14
16.05
24.36
1.36
1.73
80 to 100 %
15
38
24.36
170.6
1.73
8.82
The total score is then calculated by adding up the crash count , crash frequency , and the critical crash rate scores for a maximum of 15 and minimum of 3 . The highest ranked segments were identified and used as part of the selection of the HIN .
EXAMPLE CALCULATION
Matlock Rd ( Between Stephens St and Bardin Rd )
• Total KAB crashes ( Weighted ) = 86 o Top 20 % Quantile = 5 points
• Crash Frequency = 168 crashes / mile o Top 20 % Quantile = 5 points
• Critical Crash Rate Ratio = 12.1 o Top 20 % Quantile = 5 points
• Total Score = 15 points
HIGH-INJURY NETWORK SCREENING
The selection of the HIN prioritizes high scoring segments , while also maximizing the amount of KAB crashes and minimizing the percentage of total roadway network . Roadway segments were selected as part of the HIN with the following parameters :
• Total score is in top 40 % quantile o 11-15 total points for the Vehicular HIN o 10-15 total points for the Bicycle & Pedestrian HIN
• Gaps between high scoring segments are connected o Typically , within ~ 3 roadway segments where KAB crashes present o Lower scoring segments close most gaps
• Roadway segments capture the majority of network KAB crashes (> 50 %)
APPENDIX A : HIGH INJURY NETWORK METHODOLOGY A-5