Agenda - Environmental Policy Board - 08/21/2023

Home

the two signal-controlled intersections might be necessary, especially regarding timing. The signal timings were optimized when the 2040 builds were run but the phasing and cycle length were unchanged. The LOS of the intersections is the same as in the 2040 no build scenario and the delays saw only a slight increase at most intersections as a result of the build. The LOS of the EBL and WBL turning movements worsened as a result of the project, both from LOS D to LOS E. The stoplight may need a protected left phase at the PM peak hour for these movements similar to what the NBL and SBL movements already have. The project could also exacerbate the aforementioned issue with the left turns at the MN-47&Sunwood Dr intersection, since these movements show higher delays and in some cases LOS when compared to the 2040 No Build Scenario. The SimTraffic reports are provided in Appendix D. TURN LANE WARRANTS AT NORTH SITE ACCESS While the operations at the north site access are acceptable in all analysis scenarios, turn lane warrants were analyzed for the intersection in the build condition as the access is proposed to be converted from an exit only to full access. The necessity of southbound left turn lane and northbound right turn lane at CSAH 5 and the north site access was analyzed using NCHRP Report 457 - Evaluating Intersection Improvements: An Engineering Study Guide. CSAH 5 has a posted speed limit of 50 mph The guidelines from NCHRP Report 457 recommend that if the plotted volumes are to the right of the curves for the speed of the major road listed, a right turn lane be considered. The PM Peak hour is the highest of the three peak hours in terms of volumes at the intersection. Table 8 summarizes the results from Figure 2-6 from NCHRP Report 457. A northbound right turn lane is not warranted in 2027 or 2040. Table 8-Right-Turn Lane Warrants Major Road Right Turn Limiting Right Turn Condition Volume Volume Right TurnWarranted (veh/h) (veh/h) VolumeYes/no? (veh h/ ) 2027—PM Peak Hour 442 5 28 No 2040—PM Peak Hour 496 5 25 No The guidelines from NCHRP Report 457 recommend that if the plotted volumes are to the right of the curves for the speed of the major road listed, a left turn lane be considered. The PM Peak hour is the highest of the three peak hours in terms of volumes at the intersection Table 9 summarizes the results from Figure 2- 5 from NCHRP Report 457. A southbound left turn lane is not warranted in 2027 or 2040. Haviland Fields-Ramsey, MN Traffic Impact Analysis I July 2023