The Chickamauga Lock Replacement Project in Chattanooga, Tenn., is advancing with the U.S. Army Corps of Engineers seeking a contractor for the final phase of work. Officials estimate the price somewhere between $100 million and $250 million, solicitation documents show.
The firm fixed-price contract would cover construction of the downstream approach walls extending under and beyond a railroad bridge, records show. It would also include construction of a pair of 30-ft-dia mooring cells, plus connecting the upstream approach walls to the lock chamber and related work. The contractor would finally be responsible for decommissioning the original lock, installing a concrete thrust block and stone infill to resist concrete expansion and wet commissioning of the new lock chamber.
Work on this contract is expected to overlap with the two earlier contracts, according to Capt. Joseph Cotton, project manager with the Corps’ Nashville District. The Corps previously awarded a $245-million lock chamber contract to Shimmick Construction Co. Inc. in 2017 and a $61-million upstream approach wall contract to CJ Mahan Construction Co. LLC in 2021.
The Corps issued a request for proposals this month for the project's final contract, and responses are due by May 20. Officials expect to award the contract in the fall, according to Cotton.
The lock is located on the Tennessee River at the Chickamauga Dam, which forms Chickamauga Lake. An average of 1 million tons of cargo pass through it each year and it is the second-most used lock nationally for recreation with an average of 3,500 vessels per year, according to the Corps. The lock was built in 1940. It has needed repairs related to alkali aggregate reaction, which has resulted in outages.
The planned 110-ft x 600-ft lock would allow up to nine barges through at a time, compared to just one barge with the current lock, which measures 360 ft x 60 ft.
“This replacement project will increase reliability of the inland navigation system and improve the overall efficiency of industry for many years to come,” Cotton said in a statement.
Officials have previously said they expect the new lock chamber to be completed in the fall of 2026, and for most of the other work to be finished by the end of 2028.
The Tennessee Valley Authority owns the Chickamauga Dam, which includes a 119-MW hydroelectric plant. The Corps is responsible for maintaining the river’s navigation channel. Through a partnership with TVA, the Corps operates nine locks on the Tennessee River and one on the Clinch River.
