Portfolios and Case Studies

TH 61/TH 97 Roundabouts

Written by Admin | June 14, 2022

Challenge

Prior to construction, complex intersections at TH 61 and TH 97 were prone to vehicle crashes and unfriendly to both bicyclists and pedestrians trying to navigate their way across. Complex intersection geometrics posed issues for drivers and pedestrians alike, with a combined 60 crashes in the project area from 2007 to 2009. In addition, this corridor is in close proximity to Forest Lake Area High School, which has a high traffic volume around the school day start and end times.

Solution

The fundamental goal of the TH 61 and TH 97 Roundabouts project was to resolve poor levels of service and operations and improve safety at the north and south intersections of these two trunk highways. To reach this goal, SEH was selected to lead highway design and roundabout design, among other critical tasks. The SEH team's close coordination with the City of Forest Lake and other stakeholders ultimately led to selection of the preferred alternative to design and construct two roundabouts, realign northbound TH 61 and convert the old northbound pavement into an access road for Forest Lake Area High School. This provided a safe place for buses to queue rather than on the TH 61 shoulder.

Additional safety enhancements incorporated by the project team included a grade-separated pedestrian bridge and designated at-grade pedestrian crossings. The design also incorporated a multi-use trail, completing a previously missing link to the Hardwood Creek Regional Trail.

Awards

  • 2018 MN Chapter (ACEC-MN) Honor Award | American Council of Engineering Companies

Project
TH 61/ TH 97 Roundabouts

Location
City of Forest Lake, Minnesota

Client
Minnesota Department of Transportation (MnDOT) Metropolitan District

Features

  • 2 new roundabouts
  • Grade separated pedestrian bridge (designed by MnDOT)
  • Designed at-grade pedestrian crossing
  • Rectangular rapid flash beacon
  • Multi-use trail

Services

  • Highway design
  • Landscape architecture and design
  • Lighting design
  • Roundabouts
  • Survey
  • Traffic engineering
  • Water resources engineering