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Page 3 of 3 17379 Twin Lakes Rd Apartments, Elk River, MN TURN LANE REVIEW Turn lane warrant guidance is provided in multiple industry sources. Based on the urban environment and local jurisdiction of Twin Lakes Rd at the proposed access driveway, National Cooperative Highway Research Program (NCHRP) Report 457 was used as a guideline. These reports are used as the basis for many agency guidelines throughout Minnesota and the Country. PM peak hour volumes were reviewed and 500 through vehicles were assumed for each northbound and southbound approach on Twin Lakes Rd (estimated from MnDOT’s Year 2024 ADT of 10,491 vehicles/day). The estimated 25 southbound left turns into the site do warrant a left turn lane (16 lefts are the threshold) and it appears that a left turn lane could easily be constructed in the existing median. The estimated 26 northbound right turns do not warrant a right turn lane (through traffic would have to double to meet the threshold) and a northbound right turn lane is not recommended. This turn lane layout appears to be consistent at cross-streets and access points along the corridor. ACCESS CONFIGURATION REVIEW Access configuration (full, 3/4, right-in/right only) considerations include available sight distance due to the curvature on Twin Lakes Rd, emergency vehicle access and access spacing standards. Adequate intersection sight distance at the access location is available when the 30-mph advisory speed on Twin Lakes Rd is considered for northbound vehicles coming around the curve. Additionally, trees and brush could be cleared providing more sight distance looking south around the curve. A full access would be preferred for emergency vehicle since there is only access location. SUMMARY  The number of new vehicle trips estimated to be generated by the Proposed 17379 Twin Lakes Rd Apartments Development is 65 AM peak hour trips, 82 PM peak hour trips and 981 daily trips. The peak hour intensity of new traffic on Twin Lakes Rd is minimal with around 1 additional vehicle anticipated every minute during the AM peak hour and 1.4 additional vehicles every minute during the PM peak hour. Further detailed traffic study is not necessary unless there are unique City concerns. Per typical agency standards and the Institute of Transportation Engineers’ (ITE) recommended practices, a full traffic study is generally required when a development is expected to generate more than 100 peak hour trips. This proposed development is below that threshold.  A full access on Twin Lakes Rd can be considered. The existing median is wide enough to construct a southbound left turn lane. Adequate intersection sight distance at the access location looking to the south around the curve is available when the 30-mph advisory speed on Twin Lakes Rd is considered and trees and brush can be cleared to provide even more distance. A full access would be preferred for emergency vehicle since there is only one access location. Page 35 of 82