Marine

USACE St. Paul District – Lock and Dam 3 Upper Embankments Spot Dike and Levy Improvements to the Banks of the Mississippi River Near Diamond Bluff, WI

COASTAL successfully completed a critical infrastructure project on the banks of the Mississippi River near Diamond Bluff, Wisconsin, for the USACE St. Paul District. This project aimed to bolster the river’s embankments, ensuring the safe and efficient navigation of freight along this vital waterway.

The project involved the construction of nine overflow weirs and a water control structure, along with the construction of an access trail on the river’s east bank. These measures were specifically designed to mitigate the risk of embankment failure during periods of high water flow, covering a construction footprint of approximately 4.7 acres, including 2.1 acres of designated wetland areas.

Key construction activities included the driving of 1,200 linear feet of steel sheet pile into the riverbank to depths between 40 and 80 feet, the excavation or filling of 16,000 cubic yards of material, and the reinforcement of embankment excavations with riprap over geotextile fabric. These efforts were key in strengthening a significant portion of the embankment along the 2-mile length of this project area.

Special attention was given to the environmental and cultural sensitivity of the project site. In collaboration with USACE archaeologists, we implemented protective measures to safeguard an archaeological site during the construction of the access road. This included the use of geotextile, sand cushion, and protective mats to prevent damage to the native soil.

Recognizing the project’s potential impact on local wetlands and wildlife habitats, we coordinated closely with the Wisconsin Department of Natural Resources (DNR) biologists and conservation officers to implement phasing plans to keep construction activities from disturbing nesting habitats and minimize the impact on wetlands.

Throughout the execution of these comprehensive embankment improvements, COASTAL contributed to the long-term stability and safety of the Mississippi River’s banks, ensuring the continued critical navigation of freight and protecting the surrounding natural and cultural environments.