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Traffic Impact Study Little Canada Caribou Coffee Alliant No. 218-0047.0 11 April 11, 2018 4.5 Intersection Capacity Analysis – With Improvements The logical first step in attempting to address potential operational issues under year 2020 conditions is to optimize traffic signal timing for the anticipated future volumes. Should signal timing optimization not produce the desired delay and queueing outputs, signal phasing and/or roadway geometric improvements could be considered. It should be noted that the signalized study intersection is coordinated with signals at the I-35E Northbound Ramps/ Little Canada Road and Little Canada Road/Centerville Road intersections. Optimization of this signal system was performed under the forecasted year 2020 conditions using Synchro/SimTraffic software. Results of the year 2020 intersection capacity analysis presented in Table 6 indicate that the I-35E Southbound Ramps/Little Canada Road/Country Drive study intersection could be expected to operate near the LOS C/D threshold overall with signal optimization improvements. Potential side-street delay and queueing issues on the southbound Country Drive approach are expected to be addressed without additional signal phasing and/or roadway geometric improvements. No significant impacts to other study intersection approaches were observed in the traffic simulation. Detailed operations and queuing analysis results are presented in Appendix A. Table 6 – Year 2020 Intersection Capacity Analysis with Improvements 4.6 Little Canada Road Pavement Markings and Lane Configurations A lane striping change occurred along Little Canada Road in year 2015 after the gas station/ convenience store, which previously occupied the proposed development parcel, had closed. The striping change incorporated dedicated left-turn lanes in the eastbound/westbound directions of Little Canada Road on the bridge over I-35E. While the striping change has increased capacity between the I-35E ramp terminal intersections, it now presents a potential safety issue for westbound Little Canada Road motorists desiring to access the proposed development. Confusion among westbound motorists whether to use the dedicated left-turn lane or the adjacent through lane to access the proposed development could lead to additional vehicle conflicts within an already complicated intersection. Spacing along Little Canada Road is such that the County Drive and southbound I-35E Exit Ramp intersections are forced to operate under one traffic signal. To clarify the lane designations entering this complicated area, two alternative pavement marking modifications are shown for consideration in Figure 7. Further discussion with public stakeholders is recommended to discuss the pros/cons of each alternative in determining the most appropriate pavement marking configuration for Little Canada Road, and whether or not signal indication improvements should be associated with any lane configuration changes. I-35E Southbound Ramps/ Little Canada Road/ Country Drive Traffic Signal 2020 D /D 36.0 /48.3 C /E 34.8 /58.1 Overall Intersection LOS / Worst Approach LOS Overall Intersection Delay / Worst Approach Delay Intersection Traffic Control Year AM Peak Hour PM Peak Hour LOS Delay (s)LOS Delay (s)