11/21/2013 9:50:00 AM Dakota County approves 52/86 overpass
by Ken Haggerty
The Dakota County Board of Commissioners approved $288,833 to hire engineering firm TKDA out of St. Paul for design work on a new overpass and ramp project at the intersection of U.S. Highway 52 and Dakota County 86 (280th Street) in Randolph Township to the northwest of Cannon Falls.
Dakota County and Minnesota Department of Transportation (MnDOT) are cooperating on the design and construction of the project, with a target for 2015 construction.
This project will also include reconstruction of 1.3 miles of County 86 from Hwy. 52 to the east county line.
According to information included in Dakota County Transportation Director Mark Krebsbach's request for funding for the design, since 2008 there have been 14 injury crashes and 21 property damage crashes reported at the intersection, including a fatal crash earlier this year. Of the 35 reported crashes, 19 have been right-angle crashes.
The design includes ramps in the northwest and southeast quadrants that will enter and exit from the right lane of Hwy. 52 with right turns only. All traffic crossing the highway or making left turns at the intersection would utilize the overpass, thereby providing greater safety for both through traffic and traffic turning at the intersection.
The intersection is currently scheduled for construction of a "Reduced-Conflict Intersection" (RCI) by MnDOT. An RCI would require traffic crossing 52 on 86 and traffic wanting to turn left onto 52 from 86 to turn right and make a subsequent u-turn on 52. Although an RCI design will reduce crashes at the intersection, it will not eliminate left turns like an overpass design will, noted Krebsbach.
The RCI project was originally scheduled for 2013 construction, but has been delayed to 2014 to allow for development of the overpass and interchange project as a replacement for the RCI project, said Krebsbach.
The County is the lead agency for the project, including preliminary design, right of way acquisition, and construction administration. Dakota County staff has requested MnDOT provide the final design plans for the project.
This project must be let by June 30, 2015 to take advantage of MnDOT Cooperative Agreement funds. The timeline therefore required moving quickly to hire a consultant for preliminary design engineering. MnDOT layout approval is needed within five months of execution of a contract and a 30 percent design layout is required by the end of May 2014. Right of way requirements will need to be established by the end of August 2014. MnDOT will complete final design by February 2015 for a spring 2015 letting of bids.
Four proposals were received
and evaluated by transportation staff for the design. TKDA was selected as the preferred professional design engineering consultant based on six criteria.
Dakota County staff is currently working with MnDOT to determine final State funding contribution toward construction of the project.