Purpose
The Lock Guidewalls-Distress Repair Recommendations project for Locks and Dams 2 through 10 has been ongoing since the mid-1990s. Over the years, distresses of the guidewalls have been observed. These distresses have led to primarily serviceability and safety issues associated with the kevel on the upper guidewall. In addition, the guidewall 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 guidewall 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
Guidewalls 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, guidewalls 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 on monoliths along the guidewalls at several locks. Tow traffic often reports movement in the guidewalls. U.S. Army Corps of Engineers (USACE) engineers recommend that every end monolith located the upper and lower guidewalls 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 guidewall monoliths.
Status
The 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 Lock and Dam 5 end cell is planned for construction contract award beginning of fiscal year 2026, pending available construction funding. Pending available funding, a design contract for the Lock and Dam 5A, Lock and Dam 7, and Lock and Dam 9 end cells is anticipated for fiscal year 2026 or fiscal year 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
Guidewall 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 ~$1.65 million
Lock and Dam 5A, 7, and 9 end cells
Anticipated construction cost ~$10 million each