Purpose
The Lock Guide Walls-Distress Repair Recommendations project for Locks and Dams 2 through 10 has been ongoing since the mid-1990s. Over the years, distresses of the guide walls have been observed. These distresses have led to primarily serviceability and safety issues associated with the kevel on the upper guide wall. In addition, the guide wall end monoliths have been used by the towing industry as targets when landing on each wall. These repeated impacts have contributed to the separation of the end guide wall monoliths and have caused severe concrete damage, leading to significant and costly repairs. The purpose of the end cell projects is to extend the longevity of each site and to reduce operability issues and required maintenance.
Location
Locks and Dams 5, 5A, 7 and 9.
Description
Guide walls are long extensions of lock walls, in either the upstream or downstream direction, and are parallel to the lock wall. At Mississippi River Locks and Dams 2 through 10, guide walls primarily serve to guide the long tows into the lock and to provide mooring facilities for tows too long to be accommodated in a single lockage. Periodic inspections have identified cracks in monoliths along the guide walls at several locks. Tow traffic often reports movement in the guide walls. U.S. Army Corps of Engineers (USACE) engineers recommend that every end monolith located at the upper and lower guide walls of Locks 2 through 10 have an end cell designed and constructed. The end cells will absorb energy from barge impacts and prevent damage to the guide wall monoliths.
Status
USACE has evaluated the other lock and dam sites within the St. Paul District for future construction projects. A design contract was awarded in May 2024 for the Lock and Dam 5 end cell; the construction contract for this work will be awarded in the beginning of fiscal year 2026, pending available construction funding. An Architect-Engineer Design contract for the Lock and Dam 5A and 7 end cells is planned for fiscal year 2026. Pending available funding, an Architect-Engineer Design for the Lock and Dam 9 end cell is also anticipated for fiscal year 2026 or 2027.
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
Guide wall end cell design and construction at the locks and dams is completed with 100% federal funds.
Lock and Dam 5 end cell
Anticipated construction cost ~$11 million
Funds allocated to date ~$1.80 million
Lock and Dam 5A, 7, and 9 end cells
Anticipated construction cost ~$10 million each