Chickamauga Lock at a glanceDeveloper: The Tennessee Valley Authority originally built the lock along with the Chickamauga Dam in the late 1930s.Operator: The U.S. Army Corps of Engineers operates the lock and took over its maintenance in the 1980s.Existing lock: The lock through the Chickamauga Dam is 360-feet long, 60-foot wide and was opened in 1940.New lock: The replacement lock will be 600-feet long, 110-feet wide and could be finished in six to eight years, if more funding is provided.Traffic: The lock handled about 1 million tons of freight last year, down from 2.7 million tons a year before the recession. The lock also allows hundreds of recreational boats to travel from Chickamauga Lake to Nickajack Lake.The problem: The existing lock suffers from "concrete growth" in the rock aggregate, requiring "aggressive maintenance" to maintain the lock. A new and bigger lock also would cut the time for multi-barge shipments to go through the lock.Status: Construction began on the new lock in 2005 but was largely halted in 2010 when funding ran out.Cost: The new lock is projected to cost $860 million. The Corps of Engineers has spent $186 million so far.Source: U.S. Army Corps of Engineers
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As crews work this week to assess the damaged condition of the idled lock at Chickamauga Dam, the estimated cost for its replacement continues to increase.
The projected cost of finishing a new and bigger lock at the Chickamauga Dam rose another $162 million this summer after the U.S. Army Corps of Engineers reassessed the project using a new risk-based system the agency hopes will be more reliable. The higher projection swells the estimated cost of the new Chickamauga Lock to $860 million, nearly triple the original estimate when the project was authorized by Congress in 2003.
The extra expense is making it harder to complete the new lock from the Inland Waterways Trust Fund, which is equally funded by diesel fuel taxes from the barge industry and federal dollars appropriated by Congress. There currently isn't enough money in the trust fund to sustain work at the new Chickamauga lock even though the existing lock has been temporarily shut down because of a crack in a steel support beam on the upper gate.
"The shut down of the Chickamauga Lock is a real hardship for river shipments on upper part of the Tennessee River, but hopefully this will be a wake up call for the Corps and Congress to do more to make sure the new replacement lock is funded and can be completed," said Cline Jones, the executive director for the Tennessee River Valley Association in Decatur, Ala.
The existing lock, which was built by the Tennessee Valley Authority in the 1930s, suffers from "concrete growth" in the rock aggregate of its chamber walls. The Corps, which took over operation of the lock in the 1980s, is having to do "aggressive maintenance" to keep the old lock in operation.
The lock is the most heavily monitored of any in the United States because of its crumbling condition. On Monday, a routine inspection by the Corps found a crack in the gate beam and engineers ordered the lock shut down until the gate is assessed and repairs are made.
The closing of the lock Monday forced Serodino Inc. to shut down its tugboat operation between Chattanooga and Knoxville and temporarily lay off 16 employees. Peter Serodino said he hopes the old lock is soon repaired so his employees can get back to work and industry on the river can resume river shipments.
TVA and the U.S. Department of Energy rely upon the river and the Chickamauga Lock for delivery of major nuclear and power plant equipment, and manufacturers like Olin in Charleston and A.E. Staley in Loudon need the river for commodity and product deliveries.
"We need this lock to stay open," Serodino said.
Bill Peoples, chief of public affairs for the Corps' Nashville District Office, said engineers from the Corps were studying the gate problem Thursday to assess what repairs will be needed before the old lock can resume operation. The Corps estimates the lock will be closed for three weeks, although that time could be changed once the lock problem is assessed and its fix is determined.
Since the lock unexpectedly shut down Monday afternoon, barge and recreational boat traffic on the Tennessee River between the Chickamauga and Nickajack reservoirs has been halted.
The closing has brought a new urgency to finishing the replacement lock even as rising costs and budget constraints make it harder to fund.
U.S. Sen. Lamar Alexander, R-Tenn., said each barge replaces 65 trucks on Interstate 75 and the river provides cheaper and more energy efficient movement of goods in the region.
"Failure of the existing lock - a real possibility if the delay in funding takes too long - would threaten jobs in Chattanooga and throughout East Tennessee, including at the Oak Ridge National Laboratory, nuclear weapons facilities, nuclear power plants and manufacturing facilities," Alexander said in a statement earlier this week. "If the Lock is closed it will put at least 150,000 trucks back on I-75, and if the new expanded Lock is built it will take 100,000 trucks off I-75."
The Corps of Engineers invested $186 million in design and construction work for the new lock from 2005 through 2010, but there has been no funding for the project since and work has been suspended and the concrete batch plants used to start the project have been moved elsewhere.
"With additional funding we could probably restart work in six months or so, and we estimate we could complete the project in six to eight years," Don Getty, project manager for the new Chickamauga Lock, said Thursday.
Getty said the delays and uncertainty of funding have pushed up the construction costs of the Chickamauga project. The new estimate also is higher because is is based upon 2024 costs, not the original estimates prepared more than a decade ago.
The new risk-based estimating process is designed to ensure at least an 80 percent probability of finishing a project at the estimated price or lower. The Corps adopted the new cost-projection approach to limit the agency's frequent cost overruns on major projects.
At the Olmsted Lock and Dam on the Ohio River, for instance, the projected cost of the project jumped the original 1995 estimate of $775 million to a new estimate of $3.1 billion in 2024 dollars. The extra funds required to replace two 1920's era Ohio River dams has absorbed virtually all of the money available to build new locks and dams in the federal Inland Waterways Trust Fund.
The House and Senate have voted differing budget versions for fiscal 2015 to allocate more money for inland waterway projects and Alexander said he hopes in the lame duck session after next Tuesday's election that Congress might also raise the diesel tax on barges to provide even more funds.
The Chickamauga Lock replacement project is fourth in line for federal funding, behind the Olmsted lock and dam in Ohio, the lower Monongehela lock and dam in Pennsylvania and the Kentucky Dam in Kentucky.
Contact Dave Flessner at email@example.com or at 757-6340.