Final Chickamauga Lock Contract Awarded
The Nashville Engineer District announced the award of the final contract in the Chickamauga Lock Replacement Project on February 13 to C.J. Mahan Construction Company LLC of Urbancrest, Ohio.
The project, at Tennessee River Mile 471 in Chattanooga, Tenn., replaces the 60-by-360-foot lock built in 1940 with a new 110-by-600-foot lock. An alkali-aggregate reaction in the concrete of the original lock is causing concrete to expand and crack and has led to structural deficiencies.
The base approach wall and decommissioning contract was awarded for $192,143,924.90 and includes the downstream approach walls, breaching the existing dam to connect the upstream approach to the new lock, bringing the new lock into operation and removing the cofferdam, according to a news release from the district.
“We are proud to award this contract for this important navigation infrastructure project,” Lt. Col. Guillermo Guandique, Nashville District commander, said in the release. “The entire USACE team managing this project is ready to work with our contract partner and move the project to the finish line and deliver a new and larger operational lock.”
The lock replacement project was authorized in 2003, with construction beginning the following year. Construction was suspended from 2012 to fiscal year 2015 due to funding restraints within the Inland Waterways Trust Fund.
Lee Roberts, a public affairs specialist for the Nashville Engineer District, said the new lock is now expected to be operational in 2028, once the cofferdam is breached, the riverside approach walls are complete and portions of the existing dam spillway and gates are removed.
The final construction contract will commence once the upstream approach wall work is complete and when portions of the cofferdam work areas are made available by the lock chamber contractor, Shimmick Construction Company, Roberts said. The lock chamber contract is approximately 76 percent complete, according to the Nashville Engineer District. Construction of the upstream approach wall, also by contractor C.J. Mahan, is roughly 70 percent complete.
Before beginning mobilization on the final contract, C.J. Mahan will create a detailed construction schedule for the upcoming work. An updated project timeline will be available following the finalization of that schedule, Roberts said.
The new lock will handle nine jumbo (35-foot by 195-foot) barges in one lockage, compared to one barge per lockage in the existing lock, an 80 percent increase in efficiency to the navigation industry.
“When complete, recreational vessels and commercial tows will maintain access to 318 miles of navigable waterways upstream, and tows will more efficiently deliver commodities up and down the Tennessee River,” said Bob Winters, Nashville District project manager.
Featured image caption: An aerial photo from January 21 shows the progress of construction at the Chickamauga Lock Replacement Project. The Nashville Engineer District announced the award of the final contract in the project February 13. (Photo by Nashville Engineer District)
