Shoreline rehabilitation and outfall stabilization along Lake Superior

AMI provided design and construction administration services for multiple shoreline restoration projects along Congdon Boulevard in Duluth, Minnesota.

AMI completed shoreline rehabilitation projects at two locations along Congdon Boulevard, including the design of a concrete retaining wall and rehabilitation of a failing bin wall system. Both projects addressed shoreline deterioration caused by wave action, ice forces, and ongoing erosion while protecting infrastructure located along the Lake Superior shoreline.

The concrete retaining wall project was located along a curved section of highway with limited site access. AMI developed a design that restored shoreline conditions and helped protect the roadway from slope failure. Improvements included a concrete seawall anchored to bedrock, a concrete apron at a previously failed outfall, and placement of armor stone behind the wall based on wave analysis and overtopping evaluations.

At this Congdon Boulevard site, AMI addressed deterioration of an existing corrugated steel bin wall that had experienced corrosion, soil loss, and structural distress. The project also included rehabilitation of a large outfall affected by settlement and shoreline instability. AMI developed a repair strategy that incorporated galvanized steel plating, micropiles (rock bolts), and mass concrete placements to stabilize the structure and extend its service life.

Throughout construction, AMI provided construction administration services, including contractor coordination, documentation of field conditions, review of construction progress, and communication with the City regarding project status and potential design modifications. The project also included improvements to the stormwater system through the design of an enlarged inlet structure to better capture runoff from the adjacent roadway.