The U.S. Army Corps of Engineers Nashville District and the Tennessee Valley Authority have released a timeline for planned repairs to the main chamber at Wilson Lock, which has been closed since Sep. 25, 2024.
The current projected date for reopening the main chamber is spring 2025. This timeline is subject to change dependent on many factors, including weather and the availability of materials and staff.
“We understand that the closure of the main chamber has a significant impact on the navigation industry that operates on the Tennessee River,” said Lt. Col. Robert Green, USACE Nashville District commander. “Returning the main chamber of Wilson lock to operation as soon as possible is a priority for USACE and the Nashville District in particular.”
Green added, “we are conducting temporary repairs over the next month and once complete, we will be coordinating with our partners at TVA to evaluate risks associated with returning the main chamber to limited operations while parts are fabricated for a more permanent repair.”
With a maximum lift of 100 feet, the main chamber at Wilson Lock is the highest single-lift lock east of the Rocky Mountains. An auxiliary chamber has two 60-by-300-foot chambers that operate in tandem. The auxiliary chamber is currently open, although its smaller size and longer lock times have led to shipping delays. The lock and dam provides flood mitigation, hydropower generation and navigation control for the community of Florence, northern Alabama in general, and the inland shipping industry.
The USACE Engineer Research and Development Center (ERDC) in Vicksburg, Miss. assigned a Remotely-Operated Vehicle team to assist the Nashville District in obtaining underwater photos and video footage of the cracks in the lock gates. The Great Lakes and Ohio River Division has also tasked vessels from the Rivers Regional Repair Fleet to position at Wilson Lock to assist with moving heavy equipment and gate components during repair operations.
Key milestones in the repair timeline include:
• Repairs to the river caisson slot, completed mid-November.
• USACE-TVA risk assessment, scheduled to be completed in early December.
• First dewatering of the main chamber lower end to inspect and conduct initial repairs to assess the risk of returning to limited operation, scheduled from early November to late December 2024.
• Determining the root cause of the pintle cracking, scheduled to be completed by the end of 2024.
• Second dewatering to replace pintle assemblies and complete repair and stabilization of the gates, scheduled for the first three months of 2025.
• Completion of repairs to the pintle and gates, scheduled to be completed in spring 2025.
“Our goal is to complete this repair as soon as possible while doing our utmost to ensure the safety of our crews,” said Megan Simpson, Maintenance section chief with the Nashville District. “Wilson Lock is a vital component of a navigation system that helps provide economic and hydrological stability to the Tennessee River Basin.”
The Tennessee Valley Authority owns the locks and dams along the Tennessee River and the U.S. Army Corps of Engineers operates and maintains the locks for navigation, in partnership with TVA.
The Nashville District has a longstanding partnership with the Tennessee Valley Authority to operate and maintain navigation facilities on the Tennessee River. More than 11.4M tons of goods make their way to and from the Ohio River every year through USACE-managed locks on the Tennessee River.