For the Chicago Avenue and Waterman Drive intersection, further analysis was performed, considering that (1) the EB left/thru movements on Waterman Drive are expected to increase; (2) the stacking of the EB left/thru movement on Waterman Drive prohibits the EB right turning movement; and (3) two cyclist crashes have occurred at this intersection in 2022, or 20% of all crashes on Waterman Drive during the crash study period. A roundabout analysis was completed in SIDRA 9 to evaluate roundabout operations at the Chicago Avenue and Waterman Drive intersection.
As shown in Table 6-4, the suboptimal queueing conditions of the EB movements in Table 6-3 is resolved with a proposed roundabout. Moreover, a roundabout would provide a safer condition for all transportation modes, considering the two crashes with bicyclists in 2022.
Table 6-4: LOS, Delay and Queue Length Summary
2034 Background Conditions
Chicago Avenue/ Waterman Drive Roundabout
SIDRA CAPACITY ANALYSES - Delay, LOS, and Maximum Queue Length Summary
Background Weekday 2034
Chicago Avenue/Waterman Drive Roundabout
Intersection and Type of Control Movement and Approach Turn Lane Storage (ft) AM PEAK HOUR PM PEAK HOUR MIDDAY PEAK HOUR
Delay1 (sec/veh) LOS1 HCS 95th Percentile Queue Length (ft) Delay1 (sec/veh) LOS1 HCS 95th Percentile Queue Length (ft) Delay1 (sec/veh) LOS1 HCS 95th Percentile Queue Length (ft)
Chicago Avenue (N-S) EB Approach 6.4 A 37.3 7.2 A 45.4 4.9 A 19.6
Waterman Drive (E-W) WB Approach 4.7 A 5.4 5.3 A 8.1 4.0 A 2.2
Roundabout NB Approach 5.7 A 29.7 7.6 A 59.2 5.0 A 24.2
SB Approach 6.4 A 50.9 7.9 A 85.2 4.9 A 32.3
Overall 5.0 A 50.9 7.6 A 85.2 4.9 A 32.3
6-9