Agenda - Planning Commission - 08/02/2018

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destined for the North Dayton development. As River Hills Parkway is a two-lane roadway the daily volume capacity is up to 18,300 vehicles per day. However, as the road is a residential roadway a livability threshold of 1,000 vehicles can also be considered. This means that the roadway has sufficient capacity for the projected 2025 build volumes and issues are not expected due to traffic volumes. However, volumes may be higher than preferred by residents. Once additional accesses are added to the North Dayton site along N Diamond Lake Road, such as the northern Zanzibar Lane extension, these volumes are expected to decrease. An additional planning level review of 70th Street and River Road north of the development and east of TH 101 was completed to determine if the existing two- lane configuration with by-pass lanes is sufficient for the expected 2025 volumes. With less than five percent of expected trip generation originating from this area, only minor increases in traffic are expected due to developments within Dayton. Based on MnDOT's most recent AADT counts, River Road carries roughly 5,300 vehicles a day with 70th Street carrying less than 1,000 vehicles per day. Based on the determined trip generation and a two percent per year traffic increase, both roadways are well below their planning level capacities even if all the generated traffic entering Dayton River Road from the north was condensed on either of the roadways. b. Existing and 2025 Intersection Vehicular Analysis Individual intersections can perform poorly during peak periods while the overall roadway corridor is operating with an uncongested daily volume to capacity ratio lower than 1.0. Therefore, capacity analyses are performed for the study intersections to determine if they need improvements such as turn lanes or an upgrade in traffic control. The existing and forecasted turning movement volumes along with the existing intersection configurations and traffic control were used to develop the average delay per intersection in each study scenario. The delay calculations were done in accordance with the Highway Capacity Manual, 6th Edition using the Vistro software package. The full calculations for each study scenario, including Level of Service (LOS) grades and queue lengths, are included in the Appendix. Also, included in the Appendix is a guide explaining the Level of Service grade concept. Chart 2 (a.m. peak hour) and Chart 3 (p.m. peak hour) show the average peak hour delay per traffic signal -controlled intersection for each study scenario. The LOS D/E boundary of 55 seconds of delay per vehicle is considered the threshold between acceptable and unacceptable traffic signal operation in Minnesota. The initial signal timing for the existing conditions was provided by the County and MnDOT. Based on ITE's recommendation of updating traffic signal timing plans every three to five years, the signal timing plans used in the 2025 analysis models were optimized to best accommodate the forecasted traffic volumes. Traffic Impact Study 11 North Dayton Development CONSULTING