By Lee Roberts
CHATTANOOGA, Tenn. (Feb. 3, 2021) – The 55th chief of engineers visited the Chickamauga Lock Replacement Project on the Tennessee River today to meet with project managers and engineers and gain a better understanding of ongoing construction of a new lock chamber.
Lt. Gen. Scott Spellmon, commanding general of the U.S. Army Corps of Engineers, welcomed Congressman Chuck Fleischmann, Tennessee 3rd District, and they received a project update, toured the existing Chickamauga Lock, then moved inside the coffer dam to get an up-close view of work crews placing concrete to build a monolith for the new 110-by-600-foot navigation lock.
The contractor, Shimmick Construction, operated a conveyor system to move concrete more than 900 feet over the existing lock, into a tower-belt system and down inside the coffer dam. The system places 200 yards of concrete per hour.
Maj. Gen. Robert F. Whittle Jr., Great Lakes and Ohio River Division commander; and Lt. Col. Sonny Avichal, Nashville District commander, joined the chief of engineers and congressman for a press conference following the tour.
In addressing the media, Fleischmann lauded the work of the Corps of Engineers and announced that $191 million has been appropriated for the project in the fiscal year 2021 budget.
“We have attained almost full funding for the entire new lock project,” Fleischmann said.
Fleischmann said the Corps of Engineers is doing an exemplary job of maintaining the existing navigation lock to keep it open to commercial and recreational vessels until the new lock begins operating.
“There are over 3,000 monitoring devices on the existing lock. A typical lock might have 100 devices. I’m here today to say that the existing lock is doing exceedingly well,” Fleischmann added.
Spellmon, who became chief of engineers in September 2020, said Chickamauga Lock is one of 239 lock chambers that the Army Corps of Engineers is responsible for nationwide.
“I want to thank Congressman Fleischmann for his leadership in getting the Corps the funding to bring this project to fruition,” Spellmon said. “The vision of the Corps is ‘We want to deliver engineering solutions for our nation’s toughest challenges.’ This is certainly one of them, and with the congressman’s leadership, he’s giving us the resources to get a project done on time and within budget.”
Shimmick Construction has worked over one million man-hours constructing the lock chamber without a lost-time accident.
“That’s a big, big deal,” Whittle said. “As you can tell, there is a lot of work getting done here. They are doing a great job. And again, with all that work and everything you have witnessed observing the project, you can see that safety record is really something to behold.”
Whittle also noted the great partnership between the Corps of Engineers and the Tennessee Valley Authority. Chickamauga Dam is a TVA project; the Nashville District operates and maintains the navigation lock.
“I just want to thank them publicly for everything they do to help us, and I know we are helping them as well. That partnership is absolutely vital,” Whittle said.
Avichal, who is responsible for managing the construction project, said he is massively impressed with the teamwork between the Corps, TVA and the contractor, which is placing 240,000 yards of concrete.
To put the concrete placement in perspective, he said it’s enough to build a two-lane highway from the lock in Chattanooga all the way to Nashville, Tennessee.
The Nashville District plans to advance construction of the upstream approach wall with an award scheduled for September 2021. Additional work on the downstream approach walls, decommissioning of the existing lock, and site restoration is planned in future contracts.
Project Manager Adam Walker said the Corps of Engineers has expended $316 million or about 42 percent of the total estimated project costs through December 2020. With the $191 million appropriation announced by the congressman, all future construction contracts can be fully funded, he said.
TVA completed construction of Chickamauga Lock and Dam in 1940. With a single chamber measuring 60-by-360 feet, the lock has since experienced structural problems resulting from alkali aggregate reaction between the alkali in the cement and the rock aggregate, which results in a physical expansion of concrete structures. The current lock chamber is also incompatible with today’s towing equipment resulting in longer than normal tow-processing times. When the new larger lock is completed, it is expected to keep open 318 miles of navigable river miles upstream of Chickamauga Lock and Dam and speed up the process of locking through with ability to process up to nine jumbo barges in one lockage. The existing lock can only handle one barge at a time.
