US Army Corps of Engineers
Nashville District

District Digest News Stories

Chickamauga Lock Replacement Project builds on Joint Risk Register

Nashville District Public Affairs
Published April 26, 2019
Construction workers with AECOM work in the coffer dam to prepare the foundation April 25, 2019 for concrete placement as part of the Chickamauga Lock Replacement Project Lock Chamber Contract, which is managed by the U.S. Army Corps of Engineers Nashville District.  The Tennessee Valley Authority project is located on the Tennessee River in Chattanooga, Tenn. (USACE photo by Lee Roberts)

Construction workers with AECOM work in the coffer dam to prepare the foundation April 25, 2019 for concrete placement as part of the Chickamauga Lock Replacement Project Lock Chamber Contract, which is managed by the U.S. Army Corps of Engineers Nashville District. The Tennessee Valley Authority project is located on the Tennessee River in Chattanooga, Tenn.

Construction workers with AECOM work in the coffer dam to prepare the foundation April 25, 2019 for concrete placement as part of the Chickamauga Lock Replacement Project Lock Chamber Contract, which is managed by the U.S. Army Corps of Engineers Nashville District.  The Tennessee Valley Authority project is located on the Tennessee River in Chattanooga, Tenn. (USACE photo by Lee Roberts)

Construction workers with AECOM work in the coffer dam to prepare the foundation April 25, 2019 for concrete placement as part of the Chickamauga Lock Replacement Project Lock Chamber Contract, which is managed by the U.S. Army Corps of Engineers Nashville District. The Tennessee Valley Authority project is located on the Tennessee River in Chattanooga, Tenn.

Construction workers with AECOM work in the coffer dam to prepare the foundation April 25, 2019 for concrete placement as part of the Chickamauga Lock Replacement Project Lock Chamber Contract, which is managed by the U.S. Army Corps of Engineers Nashville District.  The Tennessee Valley Authority project is located on the Tennessee River in Chattanooga, Tenn. (USACE photo by Lee Roberts)

Construction workers with AECOM work in the coffer dam to prepare the foundation April 25, 2019 for concrete placement as part of the Chickamauga Lock Replacement Project Lock Chamber Contract, which is managed by the U.S. Army Corps of Engineers Nashville District. The Tennessee Valley Authority project is located on the Tennessee River in Chattanooga, Tenn.

Construction workers with AECOM work in the coffer dam to prepare the foundation April 25, 2019 for concrete placement as part of the Chickamauga Lock Replacement Project Lock Chamber Contract, which is managed by the U.S. Army Corps of Engineers Nashville District.  The Tennessee Valley Authority project is located on the Tennessee River in Chattanooga, Tenn. (USACE photo by Lee Roberts)

Construction workers with AECOM work in the coffer dam to prepare the foundation April 25, 2019 for concrete placement as part of the Chickamauga Lock Replacement Project Lock Chamber Contract, which is managed by the U.S. Army Corps of Engineers Nashville District. The Tennessee Valley Authority project is located on the Tennessee River in Chattanooga, Tenn. (USACE photo by Lee Roberts)

Construction workers with AECOM work in the coffer dam to prepare the foundation April 25, 2019 for concrete placement as part of the Chickamauga Lock Replacement Project Lock Chamber Contract, which is managed by the U.S. Army Corps of Engineers Nashville District.  The Tennessee Valley Authority project is located on the Tennessee River in Chattanooga, Tenn. (USACE photo by Lee Roberts)

Construction workers with AECOM work in the coffer dam to prepare the foundation April 25, 2019 for concrete placement as part of the Chickamauga Lock Replacement Project Lock Chamber Contract, which is managed by the U.S. Army Corps of Engineers Nashville District. The Tennessee Valley Authority project is located on the Tennessee River in Chattanooga, Tenn.

CHATTANOOGA, Tenn. (April 26, 2019) – As Corps of Engineers officials and their contract partner prepare to place concrete for a new navigation lock at Chickamauga Dam on the Tennessee River, they are actively working together to reduce safety risk as well as construction risks that could affect contract costs and schedule, and identify opportunities for improvement as part of a headquarters pilot program called the “Joint Risk Register.”

According to Adam Walker, U.S. Army Corps of Engineers Nashville District project manager for the Chickamauga Lock Replacement Project, the register is being used to identify risk, potential impacts, and mitigation measures associated with the lock chamber contract.

Nashville District’s construction reps coordinate weekly, monthly, quarterly and as needed with the team at AECOM to communicate and update the register to keep the project safely moving forward and to find opportunities to improve processes. The register is also visible away from the job site in both organizations for additional input and direction.

“It highlights risk that they identify as part of their workflow and we’ll identify risk that we identify from the government’s point of view, and just talk about them as a group and figure out what is the best way to mitigate those and get ahead of them before they actually occur,” Walker explained.

The contractor is on site and has already constructed a concrete batch plant. A prime example of improvement identified as part of the Joint Risk Register involved obtaining four material storage silos for concrete production from the Louisville District’s operational Olmstead Dam Construction Project on the Ohio River.  The additional silos provide a full month of material storage for use during peak production.

“The contractor came to us and identified that there is a risk of having a shortage of materials for concrete placements, and they could benefit from something like this,” Walker said.

AECOM is currently mobilizing equipment into the coffer dam and building a conveyor system that will stretch about 900 feet from the batch plant, under the highway bridge, over the existing navigation lock, and into the coffer dam. When complete, the conveyor belt system enables the contractor to move up to 200 yards of concrete per hour into a tower-belt system inside the coffer dam as needed over the duration of construction of the new 110-by-600-foot navigation lock.

Bill Groth, AECOM project manager, said having a Joint Risk Register is unique for the $240 million contract because it does provide a systemic process to collectively mitigate risk while constructing the monoliths for the lock chamber and installing the miter gates.

“Having a Joint Risk Register and being able to share the concerns of both parties, I think we’re working toward a common goal of addressing everyone’s concerns – at the same time lowering the stress levels on the job because now we know what’s ahead of us. We can plan for those things, and then when something new pops up we’re only dealing with one issue, not many issues,” Groth said.

He noted that with this project there is open dialogue and discussion in advance to identify things that can happen and then to identify ways to mitigate the risks. For instance with the conveyor system, he said they discussed what could happen to people and things beneath it. As a result, pans and nets are being placed beneath the conveyors to catch dropped objects.

“Anytime we can have a meeting or system that involves more open dialogue, I think it’s really good,” Groth added.  “I think a lot of confusion comes in projects from people not really understanding each other and a failure to communicate, and failing to communicate until it’s too late, until things have gone awry.”

Groth stressed that communicating early and expressing concerns on both sides makes it possible to deal with issues in a timely manner to promote safety, save costs, and expedite scheduling.

The U.S. Army Corps of Engineers Headquarters began testing the Joint Risk Register in 2018 at the Chickamauga Lock Replacement Project, but has since implemented the register across the entire Corps of Engineers, including all other projects within the Nashville District.

Kenny Simmons, architect in the U.S. Army Corps of Engineers Construction Branch, said the Joint Risk Register makes it possible for the Corps to build relationships and collaborate with private sector partners while developing processes and tools to deliver projects more effectively.

“Chickamauga Lock is an excellent test project for the Joint Risk Register,” Simmons said. “We’ve been working with them to fine tune the strategy before rolling it out as formal policy.  They have been giving us feedback on a monthly basis on the progress and possible adjustments we’ll make to that policy in the future to better prepare the Corps of Engineers across the enterprise.”

As the Corps rolls out more advanced partnering techniques for construction contracts, officials plan to include the Joint Risk Register in formal policy updates.

“So this is just one tool in the tool bag for working with private industry after a contract is awarded, and in being more successful in project delivery,” Simmons said.

In keeping with the chief of Engineers’ call to revolutionize how the Corps of Engineers conducts its business, Nashville District leadership welcomed the opportunity to make the Chickamauga Lock Replacement Project a test project for the register.  

“We saw that as a significant opportunity for us to help shape enterprise level policy,” said Lt. Col. Cullen Jones, Nashville District commander.  “Going into the initial partnering meeting we sat down and kind of explained that we’re going to be the example that other large-scale projects are going to be moving to into the future.”

Jones said the cross talk with AECOM is making it possible to actively mitigate risks and capitalize on the opportunities to aggressively deliver the project.

“Looking at both the risks that we have in the future and putting controls in place to mitigate them so they don’t hinder production, while at the same time looking at ways we can capture a schedule advantage and maintain a high quality… that’s going to eventually save us money and be of greater benefit to the taxpayer.”

Headquarters is actively monitoring the efforts to reduce risk at the project to share both successes and lessons learned corporately across the Corps of Engineers, while the project reaps the benefits from the register, which reduces risk and keeps the construction project moving safely ahead toward completion.

The Tennessee Valley Authority 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 and speed up the process of locking through with ability to process up to nine jumbo barges in one lockage.

(The public can obtain news, updates and information from the U.S. Army Corps of Engineers Nashville District on the district’s website at http://www.lrn.usace.army.mil, on Facebook at http://www.facebook.com/nashvillecorps, and on Twitter at http://www.twitter.com/nashvillecorps.)