Case study | Structural Engineering
METRO Blue Line Extension (Bottineau)
Details
Owner
Metropolitan Council
Client
Kimley-Horn and Associates, Inc.
Project Cost
$1.536 Billion
Status
Completed 2022
Summary
The planned METRO Blue Line Extension (Bottineau) light rail transit project will expand the existing Blue Line 13 miles northwest from downtown Minneapolis through north Minneapolis, Golden Valley, Robbinsdale, Crystal and Brooklyn Park, drawing riders northwest of Brooklyn Park. The line has 11 new stations in addition to Target Field Station where it will continue as the METRO Blue Line, providing one-seat rides to Minneapolis-St. Paul International Airport and the Mall of America. It connects Minneapolis and the region’s northwest communities with existing LRT on the METRO Green Line, future LRT on the METRO Green Line Extension (Southwest LRT), bus rapid transit on the METRO Orange Line and METRO Red Line, the Northstar commuter rail line and local and express bus routes.
Project
Kaskaskia Engineering Group, LLC (KEG) provided noise wall and retaining wall design and plan development for the project. A total of five miles of retaining walls were required, and in some of those areas noise walls were built on top. The types of retaining walls constructed along the corridor included a corridor protection wall between the existing BNSF railroad and the LRT line, cast-in-place concrete, and soldier pile retaining walls.
In addition to the noise walls constructed on top of retaining walls, there were additional freestanding noise walls along the corridor. The noise walls consist of concrete posts with timber battens and planks. In addition to the structural design, aesthetics played a key role in the design and development of the noise walls. Throughout the corridor, soil conditions were not optimal adding additional challenges to the project.
The rail line goes through residential areas where barriers are needed to prevent people from accessing the tracks or the overhead electric lines. Additionally, KEG assisted other consulting firms in designing soldier pile walls and cast-in-place walls along the route.