Chickamauga Lock Fact Sheet
Chickamauga Lock Replacement
Description: The US Army Corps of Engineers completed a feasibility study of structural deficiencies at the existing lock in March 2002 at the request of the Tennessee Valley Authority, and recommended replacement of the lock. In February 2003, Congress authorized a 110-foot x 600-foot replacement lock and provided funding for a construction start in December 2003. The project includes relocation of roads and bridges.
Background: Chickamauga Lock is seven miles northeast of Chattanooga at Tennessee River Mile 471. The 60 feet x 360 feet lock has been in operation since 1940. From 1997 to 2003 annual tonnage passing through the lock ranged from 1.9 to 2.7 million tons. Currently some 1.3 million tons of traffic pass through each year. Soon after construction, TVA recognized that an alkali aggregate reaction problem, commonly called concrete growth, existed throughout the project. This expansion of concrete leads to stability concerns throughout the structure and misalignment of mechanical components. Engineering reliability studies indicate that the probability of an event with unacceptable, possibly even catastrophic results, increase significantly after 2010. The problem will continue to affect lock operations, and at some point the probability of such an event would cause TVA’s Dam Safety Officer to permanently close the lock to protect the public downstream of the project and TVA’s investment in other features of the project. TVA and the Corps have determined the lock could remain open until at least 2010 with an aggressive maintenance program, but costs to maintain will begin to exceed replacement costs.
In February 1999 TVA provided funds of $1.5M to initiate feasibility studies for a Chickamauga Lock replacement. A Chief’s Report was signed in May 2002 recommending construction of a 75-foot x 400-foot replacement lock adjacent to the existing structure. The FY2003 Energy & Water Development Appropriation authorized a 110-foot x 600-foot lock replacement and provided funds of $2.8M for design of road and utilities relocation, model construction and testing, and subsurface exploration to determine foundation conditions for the new lock.
A groundbreaking ceremony was held on June 18, 2005 to initiate the Road and Bridge Relocation Contract of $6M. This work was completed in February 2007. The 3-year cofferdam construction contract of $83M was awarded in September 2006. FY 2007 funds of $27M were used for construction of the cofferdam and to continue lock design. The Corps initiated a Limited Reevaluation Report (LLR) of Chickamauga Lock’s costs and benefits to better position the project for FY2010 budgeting. FY2008 funds of $34.6M were used to continue construction of the cofferdam and lock design. Funding of $42M was included in the President’s budget for FY2009 to continue cofferdam construction and lock component design.
The project is cost-shared 50/50 with the Inland Waterways Trust Fund. The total project cost is currently estimated to be $375M with an estimated lock completion date of 2015. Delays beyond that point will increase this cost estimate. Average annual benefits are $5.7M (October 2004 dollars). Approximately $173M was expended through FY2009, leaving a balance of approximately $202M to complete the project.
Importance: Chickamauga Lock is the gateway to the upper Tennessee River serving 318 miles from Chattanooga to Oak Ridge and Knoxville, Tennessee. This reach of the river provides navigation to the U.S. Department of Energy’s facilities at Oak Ridge and two nuclear power plants that serve the region. Commodities traversing Chickamauga Lock have origins or destinations in 17 states in the South, Midwest, and Mid-Atlantic regions, traveling an average 1,400 miles. Traffic forecasts by the Corp’s of Engineers’ Navigation Center indicate that tonnage levels will grow to about 11.3 million tons by 2060. Chickamauga Lock has an average locking time per tow of almost 8 hours, the highest in the Ohio River System. Only four locks in the System have a higher average delay time and none have a higher processing time. Recreational boaters use the lock at a rate of 6 to 1 over commercial vessels. In 2008, 3,985 recreational craft locked through, making the Chickamauga Lock the second busiest lock for recreation on the entire Ohio River system.
Current Work: American Recovery and Reinvestment Act funding of $62.5M is being used to fund the completion the cofferdam dam contract, mitre gate and culvert valve fabrication plus fabrication of bridges to be used during lock construction, and construction of lock approach beams.
Status: $1M funding for FY2010 will allow completion of work already under contract. Without an immediate solution to the Inland Waterway Trust Fund insolvency, the cofferdam will be completed in the summer of 2010, the water will be pumped out of the structure and tested for integrity, water will be returned and on-site construction will be suspended until Trust Fund funds become available. With two other higher priority Inland Waterway construction projects requiring the entirety of the funds at current levels, suspension of construction at Chickamauga will last more than a decade without a meaningful solution to the Trust Fund insolvency. In that period, TVA will likely close the existing lock to all traffic out of concerns for safety resulting in the Tennessee River losing 181 miles of commercially navigable waterway in addition to 61 miles of the Clinch River, 29 miles of the Little Tennessee River, and 21 miles of the Hiwassee River.