Oakland, California-based Shimmick Construction is the prime contractor to construct the new 110-by-600-foot lock chamber on the Tennessee River.
But Shimmick officials said the cost of their original $240 million project should be increased and more time given for completion due to delays and costs caused by COVID-19, material inflation, tight labor markets and supply delivery challenges. The Army Corps of Engineers and Shimmick are working through an Alternate Dispute Resolution process to resolve the contract cost issues, and a Defense Contracting Audit Agency is reviewing the project, according to a statement from the Corps.
The increased cost for the project is a combination of several factors to include recent project delays, changes in site conditions, design enhancements and the overall inflation factor associated with labor and material in today's economy," Jasper, the interim project office chief for the Army Corps of Engineers Nashville District, said in a statement.
Jasper said Shimmick expects to complete its work in August 2025, and the Corps projects the overall project will be completed "in the 2028-2029 time frame."
"An additional $237 million is required to fully fund the project," Jasper told the Inland Waterways Users Board. "Current market conditions, extended project duration and increased inflationary rates will have impacts on required cost to complete the project."
Need for a new lock
Jasper said the new lock is required due to problems with "concrete growth" in the current 83-year-old lock, "which threatens the stability and operatability of the existing lock."
The Tennessee Valley Authority, which was created in 1933 to harness the power and navigation of the Tennessee River, originally built the Chickamauga Dam and Lock using nearby rock aggregate that has since developed some structural problems.
The Chickamauga Dam remains a TVA project, but the Chickamauga Lock is maintained and operated by the Army Corps of Engineers and is funded with both congressional appropriations and proceeds from diesel taxes paid by river barges on America's inland waterways.
About 1 million tons of freight a year is moved through the Chicamauga Lock, and the new lock is projected to reduce commercial transit times by 80%. The Chickamauga Lock is also the most active lock on the Tennessee River for recreational vessels, with more than 3,500 vessel lockages annually.
Cline Jones, the executive director for the Tennessee River Valley Association, said the barge industry was "surprised" by the size of the cost increases for the Chickamauga Lock replacement. But Jones, who has advocated for the new lock for more than a decade, insists the investment will pay off America.
"This is certainly a worthwhile project with over 319 miles of navigable river above the Chick Lock, including major facilities in Oak Ridge and nuclear plants at Sequoyah and Watts Bar that depend upon the river," Jones said in a telephone interview Thursday. "Some products can only be moved by water and they can't be shipped by rail or highway. This is still very important to this region and to the country."
Jones said the bigger lock will help accommodate more and faster shipments of goods on America's inland waterways, one of the most efficient means of transporting heavy commodities and equipment.
The Corps projects the lock helps keep up to 150,000 trucks off Interstate 75 and lowers the transportation costs for many companies, including Olin Corp. in Cleveland, Tennessee, and A.E. Staley in Loudon.
Delays and cost overruns
Work on the Chickamauga Lock stalled for several years more than a decade ago when Congress didn't provide enough funds to sustain the work on the replacement lock in Chattanooga.
To help boost funding for the inland waterways network, U.S. Rep. Chuck Fleischmann, R-Tennessee, and others in Congress worked with the barge industry to gain congressional approval of an increase in the diesel fuel tax paid by barge operators to help fund part of the Inland Waterways Trust Fund that pays for dams and locks.
Fleischmann is a longtime supporter of the replacement lock at the Chickamauga Dam, jokingly calling it "the Chuck lock" because of his work on the House appropriations committee to support the replacement lock.
"These projects, like many large Corps projects, have faced delays and cost escalations, including Chickamauga Lock in my district," Fleischmann said in a statement last month. "Execution of the Chick Lock project seems to be on a better path now, but we need to continue working to improve project delivery of these critical water resources infrastructure projects."
Work continues on the lock project, but the Corps decided against allocating any new funds for more contracts in the current fiscal year while it reassessed its cost and completion schedule.
"The lack of funding this year will not impact ongoing work on the replacement lock," Jasper said in a statement earlier this year.
The upstream approach wall above the Chickamauga Dam, originally planned to be completed by May 2024, is only 12% completed. "Poor geology" has required revisions to planned foundation elevations, and the contractor has submitted a cost adjustment for redesign of the drill shafts.
To build the new replacement lock, Shimmick is excavating 9,900 cubic yards of rock, demolishing approximately 3,600 cubic yards of existing reinforced concrete spillway and installing 43 reinforced concrete drilled shafts. The project also includes the construction of a new operations building and gate control shelters, the installation of electrical and mechanical systems to support the lock and operations building, and the operation and maintenance of the automated instrumentation system and dry commissioning of the lock
The conveyor system Shimmick developed delivers concrete overland and over the existing lock to prevent any disruptions to lock operations.
"We are exceptionally proud to work on this important project for the U.S. Army Corps of Engineers – a project that will benefit the region now and for years to come – and are dedicated to delivering quality work that aligns with our commitment to providing the absolute best service and support to the communities we serve," Shimmick spokeswoman Clara Marshall said in a statement.
But Shimmick declined to discuss its requests for additional time and money to complete its work at the Chickamauga Dam. Last year, the contractor requested an additional $96.3 million and 590 days to complete its work, according to Stephanie Hall, deputy district engineer for the Nashville engineering district.
Kentucky Lock costs rise
Downstream on the Tennessee River, the new Kentucky Lock near Gilbertville, Kentucky, is facing an even bigger cost overrun than the replacement lock at the Chickamauga Dam.
Jasper told the Inland Waterway Users Board the total project cost estimate for the new Kentucky Lock indicates an additional $332 million is required to finish that project.
The Corps is adding a new 1,200-foot lock on the landward side of the existing 600-foot lock at the Kentucky Dam to expand river shipping capacity.
Delays and resulting cost increases at the Kentucky Lock project were blamed on a "very competitive labor market with limited labor resources."
Deb Calhoun, senior vice president of the barge industry trade group known as the Waterways Council, said the new and bigger locks are critical to maintaining and growing river shipping, which she said is better for the environment and helps reduce highway congestion.
"Chickamauga Lock, like many projects, is facing challenges, but we look forward to it becoming operational," Calhoun said in a statement.
Chickamauga Lock at a glance:
Developer: The Tennessee Valley Authority originally built the lock along with the Chickamauga Dam in the late 1930s.
Operator: The 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 and 60 feet wide and opened in 1940.
New lock: The replacement lock will be 600 feet long and 110 feet wide and is projected to be operational by 2029.
Traffic: The lock handles about 1 million tons of freight a year and is the busiest lock for recreational vessels on the Tennessee River. The new lock will be able to accommodate multibarge shipments and move freight faster than the existing lock.
The problem: The existing lock suffers from "concrete growth" in the rock aggregate, requiring extensive maintenance to continue operating the lock.
Cost: Construction of the new lock is now projected to cost a total of $954.4 million.
Source: Army Corps of Engineers