Agenda - Public Works Committee - 03/15/2022

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Buokhng a Bet et UVodd February 28, 2022 Mr. Bruce Westby, PE City Engineer City of Ramsey 7550 Sunwood Drive Northwest Ramsey, Minnesota 55303 Dear Bruce: RE: Ramsey, Minnesota CSAH 56 at Sunwood Drive Signal System Flashing Yellow Arrow Considerations SEH No. RAMSY 164323 On November 5, 2021, we reviewed the intersection of CSAH 56 (Ramsey Boulevard) and Sunwood Drive in the City of Ramsey with regards to proposed modification of the existing intersection traffic signal left turn operations. Recently, the City has received requests from the public to have flashing yellow arrow operation installed and activated at intersections like this throughout the City. In response to these requests, the City had SEH perform an analysis of the intersection to determine if flashing yellow arrow operation can be utilized there. The analysis includes review of the feasibility, cost, and safety of the intersection for flashing yellow arrow operations. Following are the results of our analysis. This 4-legged intersection was first signalized in 2004, with protected left turn phasing installed for the CSAH 56 approaches and protected/permissive left turn phasing for the Sunwood Drive approaches. The posted speed limit on CSAH 56 is 55 mph, while Sunwood Drive is posted at 30 mph to the north and 35 mph to the south. All intersection approaches have a single separate dedicated left turn lane. The City provided SEH with AM and PM peak period turning movement traffic counts for this intersection (taken on January 26-27, 2022, between the hours of 6-9 am and 3-6 pm). SEH also obtained crash data for the intersection for the most recent 5 years of available crash data (January 2017 to December 31, 2021) through the MnCMAT site. SEH then completed a brief field review of the signal system to confirm that the existing traffic signal plans correspond to the current installation of the signal system and take into account the current intersection geometries. As part of the field review, SEH also reviewed traffic signal cabinet components to determine if additional electrical equipment would be required to be provided in order to allow for flashing yellow arrow operation to be used. As part of the signal system installation, the CSAH 56 intersection approaches were set up to operate with protected left turn phasing (3-section RLA-YLA-GLA signals). A separate left turn signal is centered on both the northbound and southbound left turn lanes. Far -left pole mounted left turn signals also exist facing each CSAH 56 intersection approach. Through signals (3-section RYG) are centered on each through lane. Both approaches have a single left turn lane, two through lanes, and a separate right turn lane. The Sunwood Drive approaches currently operate with protected/permissive left turn phasing (5-section R-Y-G-YLA- GLA signals). A single overhead 5-section signal head exists facing the eastbound and westbound approaches, and this head is centered on the lane line between the left turn lane and through lane. No other overhead signal exists on either mast arm facing Sunwood Drive. Far left pole mounted 5-section signal heads also exist facing each approach. Engineers I Architects I Planners I Scientists Short Elliott Hendrickson Inc., 3535 Vadnai, Center Drive, St. Paul, MN 55110 SEH is 100% employee -owned I sehinc.com 1 651.490.2000 1 800.325.2055 1 888.908.8166 fax