Appendix D Traffic Impact Analysis - westplainseis.com

HCM Signalized Intersection Capacity Analysis
4: Hwy. 2 & Garfield St. 2/14/2011
Movement EBL EBT EBR WBL WBT WBR NBL NBT NBR SBL SBT SBR
Lane Configurations
Volume (vph) 141 2097 17 46 2168 266 52 29 118 215 23 110
Ideal Flow (vphpl) 1900 1900 1900 1900 1900 1900 1900 1900 1900 1900 1900 1900
Total Lost time (s) 5.5 5.5 5.5 5.5 5.5 5.5 5.0 5.0 5.0 5.0
Lane Util. Factor 1.00 0.95 1.00 1.00 0.95 1.00 1.00 1.00 1.00 1.00
Frt 1.00 1.00 0.85 1.00 1.00 0.85 1.00 0.88 1.00 0.88
Flt Protected 0.95 1.00 1.00 0.95 1.00 1.00 0.95 1.00 0.95 1.00
Satd. Flow (prot) 1787 3574 1599 1787 3574 1599 1770 1638 1805 1665
Flt Permitted 0.05 1.00 1.00 0.05 1.00 1.00 0.58 1.00 0.55 1.00
Satd. Flow (perm) 85 3574 1599 88 3574 1599 1072 1638 1037 1665
Peak-hour factor, PHF 0.93 0.93 0.93 0.93 0.93 0.93 0.93 0.93 0.93 0.93 0.93 0.93
Adj. Flow (vph) 152 2255 18 49 2331 286 56 31 127 231 25 118
RTOR Reduction (vph) 0 0 4 0 0 70 0 52 0 0 51 0
Lane Group Flow (vph) 152 2255 14 49 2331 216 56 106 0 231 92 0
Heavy Vehicles (%) 1% 1% 1% 1% 1% 1% 2% 2% 2% 0% 0% 0%
Turn Type pm+pt Perm pm+pt Perm Perm Perm
Protected Phases 1 6 5 2 4 8
Permitted Phases 6 6 2 2 4 8
Actuated Green, G (s) 94.7 88.2 88.2 89.7 85.7 85.7 32.0 32.0 32.0 32.0
Effective Green, g (s) 94.7 88.2 88.2 89.7 85.7 85.7 32.0 32.0 32.0 32.0
Actuated g/C Ratio 0.68 0.63 0.63 0.64 0.61 0.61 0.23 0.23 0.23 0.23
Clearance Time (s) 5.5 5.5 5.5 5.5 5.5 5.5 5.0 5.0 5.0 5.0
Vehicle Extension (s) 3.0 3.0 3.0 3.0 3.1 3.1 3.0 3.0 3.0 3.0
Lane Grp Cap (vph) 136 2248 1006 105 2185 977 245 374 237 380
v/s Ratio Prot c0.05 0.63 0.01 0.65 0.06 0.06
v/s Ratio Perm c0.70 0.01 0.29 0.13 0.05 c0.22
v/c Ratio 1.12 1.00 0.01 0.47 1.07 0.22 0.23 0.28 0.97 0.24
Uniform Delay, d1 46.8 26.0 9.7 33.8 27.2 12.2 44.1 44.6 53.7 44.2
Progression Factor 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00
Incremental Delay, d2 112.2 19.7 0.0 3.3 40.0 0.1 0.5 0.4 50.9 0.3
Delay (s) 159.1 45.7 9.7 37.0 67.2 12.4 44.5 45.1 104.6 44.5
Level of Service F D A D E B D D F D
Approach Delay (s) 52.6 60.8 44.9 81.6
Approach LOS D E D F
Intersection Summary
HCM Average Control Delay 58.0 HCM Level of Service E
HCM Volume to Capacity ratio 1.05
Actuated Cycle Length (s) 140.2 Sum of lost time (s) 10.5
Intersection Capacity Utilization 105.9% ICU Level of Service G
Analysis Period (min) 15
Description: Optimized Timing/Phasing
Add NB Lt turn bay, reconfigure SB approach
c Critical Lane Group
West Plains Development Traffic Impact Analysis
Synchro 7 - Report
2032-Alternative 3 Buildout-Mitigated Page 3