Contact

U.S. Army Corps of Engineers
St. Paul District
Programs & Project Management

332 Minnesota St., Suite E1500
St. Paul, MN 55101

(651) 290-5755

cemvp-pm@usace.army.mil

Mississippi River Locks and Dams 2–10: Miter Gate Replacements

U.S. Army Corps of Engineers, St. Paul District
Published April 17, 2025
Updated: April 17, 2025
Purpose

Locks and Dams 2 through 10 have used the same miter gates since their construction in the 1930s. Over time, the gates have been damaged and distressed, leading to serviceability and safety issues. This project will replace the gates and upgrade the anchorage systems, increasing navigational longevity and operational readiness while decreasing repair costs and downtime due to maintenance or failure.

Location

Upper Mississippi Locks and Dams 2 through 10.

Description

To allow watercraft to pass through stretches of river of various depths, Congress authorized a series of locks and dams along the Mississippi River. Miter gates and the anchorages upon which they rest are an integral part of those locks.

Miter gates are comprised of two leaves that provide a closure at one end of a lock at a “miter,” or angle. Each lock has a set upstream and downstream miter gate. In coordination with other systems, these gates allow water levels within the lock to be controlled.

Status

Two U.S. Army Corps of Engineers (USACE) districts — St. Paul and Rock Island — have been collaborating to design and install new miter gates for the locks and dams of the Upper Mississippi. To comply with modern design codes and best practices, the new miter gates are significantly heavier than the originals. Thus, USACE is also upgrading the miter gate anchorages.

New miter gates for Locks and Dams 6, 7 and 9 are in fabrication. The Lock and Dam 6 and 7 gates are scheduled for installation in summer 2025. The Lock and Dam 9 gates are scheduled to be installed in summer 2026.

The districts awarded a fabrication contract for new Lock and Dam 3 and 4 miter gates in fall 2024. The new Lock 3 miter gates are scheduled for installation in summer 2028, and the Lock 4 gates are scheduled for installation in summer 2029.

St. Paul District engineers have completed designing new miter gates for Lock and Dam 5. USACE will advertise the Lock and Dam 5 miter gate fabrication contract in the future according to the operations division’s budget priorities.

Authority

Congress authorized the Upper Mississippi River 9-Foot Channel Navigation Project as part of the River and Harbor Act approved July 3, 1930.

Funding

Miter gate replacement design and construction at the locks and dams are 100% federally funded.

Fiscal year 2025
Lock and Dam 6 and 7 gate installation              $2,500,000
Lock and Dam 7 and 9 anchorage upgrades      $3,000,000
Lock and Dam 5 gate fabrication award            $10,000,000

Fiscal year 2026
Lock and Dam 9 gate installation                         $1,250,000