5.8. SR 02-22-2005 - Laserfiche WebLink

Home Browse Search

p.m. peak hour. With the proposed development, the northbound and the southbound left turns and the through movements will op~rate at LOS F. This situation is not uncommon,<especially. for left turns and through movements on a minor street approach with stop sign control at a high-volume roadway. Altliough traffic signal control could provide better openitionsat this intersection, this mitigation was not examined given the close 'spacing of less than 400 feet . between Carson Street and TH 169. In addition to the capacity analyses, we simulated trafficconditions-forthe 2006 build condition using the Simtraffic 6 software package. One ofthe results that the simulation generates is queues for various movements. Our simulation resulted in queuing atboth the subject interseCtions for the 2006 build condition during both the a.m. and the p.m. peak hours. These results clearly indicate that the p.m. peak hour is the most critical period for queuing. The industry practice is to design for the 95th percentile queues. The p;m. peak hour 95th percentile queue for the eastbound movements at the TH 169/Main Street inten;ection is about 276 feet, which principally is caused. by through movements. The 95th percentile queuing for the westbound movements at the Main Street/Carson Street intersection is about 74 feet, which principally is caused" by the left turns. These 95th percentile queues are within the available stacking space of about 320 feet on Main Street between Carson Street and TH 169. Our overall conclusion from the capacity analyses and simulation is that the proposed development will have minimal impacts on the TH 169/Main Street intersection and on Main Street at Carson Street. We acknowledge that the proposed access plan is not ideal and results. in individual movements operating ar poor levels of service. However, given the location of this property and the access constraints that exist, the proposed access location is the best possible solution. . Although other measures such as channelizing islands can be used to improve existing and future LOS E and F operations at the TH 169IMain Street intersection, we understand that < Mn/DOTis not planning on any changes at this intersection. Instead, discussions are underway regarding upgrading TH 169 to a freeway in the future to accommodate the already high traffic volumes. Considering findings from our analyses and MniDOT's plans for the future, we do not recommend any changes to Main Street or TH 169 to accommodate the . projected 2006 build traffic as the proposed development would not cause any significant changes in the 2006 no-build operations.