What began as a traffic study for the redevelopment of the Highland Bank site, morphed into a reconstruction project to better accommodate high volumes of traffic into and from a key shopping area in Minnetonka. In order to improve the traffic flow into and through the area, the City of Minnetonka determined the need for improvement of the I-394 ramp intersection at Plymouth Road. Under the previous configuration, only inbound access to this busy shopping area was provided on Ridgehaven Lane from southbound Plymouth Road. To provide outbound access to both Plymouth Road and I-394, Ridgehaven lane was widened and Ridgedale Drive was realigned, with a new bridge needed to allow northbound Ridgedale Drive lane to cross underneath Ridgehaven lane.
SRF developed preliminary and final construction plans, specifications and estimates for the reconfiguration of Ridgedale Drive and Ridgehaven Lane. Key to the project was the development of a vehicle and pedestrian traffic staging plan that met the needs of key businesses during construction. This partially federally funded project consisted of preliminary design, environmental documentation, and final design of roadway and utility improvements, bridge and structural retaining walls, signal and lighting systems, and streetscape improvements. Other services as part this project included traffic forecasting, survey, and right of way acquisition.
The bridge and retaining wall design was a collaborative process involving SRF’s Bridge, Roadway, and Water Resource groups, the City, and the geotechnical engineer. SRF worked with the City to develop a slab-span bridge concept that minimized structure depth and provided a cost-effective solution for this wide, short span bridge. Due to the presence of a large diameter storm sewer running through the middle of the proposed project and other utilities located within the very compressed site, extensive coordination was needed to determine appropriate retaining wall types and foundation options for both bridge and walls. SRF worked with roadway, drainage and geotechnical teams to analyze a number of design options and determine the most cost-effective solution while also minimizing risk to the City.
