The U.S. Army Corps of Engineers, St. Paul District, awarded a $2.4 million contract to American Mine Services (AMS) of Boulder, Colorado, on Sept. 28, to construct bulkhead slots on the intermediate wall and river wall upstream of the miter gates in the auxiliary lock chamber at Lock and Dam 3 located in Welch, Minnesota, on the Mississippi River.

The project work consists of the demolition of a section of the existing concrete monoliths, wall armor, ladders, handrails and electrical conduits within the footprint of the new bulkhead slots. The wall armor, ladders and handrails are replaced upon installation of the bulkhead slot assembly, a one-piece steel fabrication to support the installation of temporary bulkheads as a temporary damming surface during future replacement or maintenance of the auxiliary miter gates.

A localized cofferdam and dewatering system are necessary for the construction in the auxiliary lock and will not impact navigation. Construction completion for this work at Lock and Dam 3 is expected in December 2024.

This project is funded under the authority of the Rivers and Harbors Act of 1930. Design funding was provided through the Corps’ Operations and Maintenance Appropriation. Funding for award was received through the Fiscal Year 2023 Consolidated Appropriations Act.

The St. Paul District navigation program provides a safe, reliable, cost-effective, and environmentally sustainable waterborne transportation system on the Upper Mississippi River for the movement of commercial goods and for national security needs. To do this, the district maintains a 9-foot navigation channel and 13 locks and dams from Minneapolis to Guttenberg, Iowa. Keeping this system open is vital to the nation’s economy. Nearly 12 million tons of commodities passed through Lock and Dam 10 in 2022. This included nearly 8 million tons of farm products such as corn and soybeans. The industries making these shipments saved approximately $430 million by using the inland waterways instead of overland shipping methods.