AMI designed an emergency repair for a damaged shoreline behind the Fitger’s Complex in Duluth, Minnesota. AMI completed all City/County, USACE, and MnDNR permitting; attended numerous meetings with the City and Client’ completed climate conditions analysis; wave and impact analysis; and surcharge loading analysis. AMI engineered additional solutions that regained the structural integrity of the coastal shoreline while working closely with the City and the Client.

A combination of reinforced concrete retaining walls and steel sheet pile cutoff walls were designed and installed due to varying bedrock elevations. AMI analyzed the local climate conditions and designed the retaining walls for wave and ice impacts and surcharge loading from emergency vehicles. Additionally, a new boardwalk was designed as a result of the project’s high-profile and tourist location. The boardwalk was designed to closely match the existing boardwalk with the ability to remove it per the Client’s request. The boardwalk and asphalt-paved lakewalk was also widened to accommodate emergency vehicles.

The shoreline’s original damage occurred from previous storm events and elevated water levels. Two days into this project, additional erosion, roadway and shoreline damages, and loss of on-site materials occurred as a result of the October 2018 Lake Superior storm. The storm’s repercussions included an additional 50 ft. of repairs to the north end of the project.