Ryan Cleary (right), a civil engineer for the U.S. Army Corps of Engineers Nashville District, briefs Col. Herlihy (second from left), commander of the Great Lakes and Ohio River Division, on the installation and welding progress of the miter gates at the Chickamauga Lock Replacement Project in Chattanooga, Tennessee, Feb. 20, 2026. Looking on are Lt. Col. Guillermo Guandique (left), Nashville District commander, and Bob Winters (second from right), a project manager for the lock. USACE COURTESY IMAGE
Division Commander’s Visit Highlights People, Partnerships in Mission Delivery
Key Themes: Workforce excellence, regional partnerships, and infrastructure modernization
Project Impact: 80% reduction in river transit times; enhanced flood control safety
NASHVILLE, Tenn. — To truly understand the challenges of modernizing America’s inland waterways, you have to walk the ground and talk to the people who make it happen every day. That’s exactly what Col. Daniel J. Herlihy, commander of the Great Lakes and Ohio River Division, did during a visit last week to two of the Nashville District’s most complex and critical projects.
The colonel, who assumed command of the division Aug. 13, 2025, oversees seven districts across 17 states. He visited the Nashville District Feb. 18-20 to get a firsthand look at major infrastructure projects and meet the teams making them happen. His tour focused on people and operations, with stops at Center Hill Dam in Lancaster, Tennessee, and Chickamauga Lock in Chattanooga, Tennessee.
Construction progresses on the new lock chamber for the U.S. Army Corps of Engineers Nashville District’s Chickamauga Lock Replacement Project in Chattanooga, Tennessee, shown Feb. 20, 2026. The chamber is 76 percent complete as part of a multi-contract effort to modernize the waterway. The new 110-by-600-foot lock will allow nine jumbo barges to pass through at once, a significant increase from the current single-barge capacity. USACE COURTESY IMAGE
“You can’t understand it until you walk on the ground and talk to the people and really get a firsthand view of the challenges and opportunity we have,” Herlihy said. “So, this is absolutely critical, it is something that I enjoy just getting that opportunity to see our folks.”
Herlihy toured Center Hill Dam on the Caney Fork River Feb. 19, where a significant spillway gate replacement project is underway. Onsite, project leaders briefed him on the history that necessitated the replacement of the dam’s eight massive spillway gates. Officials explained that during the wettest season on record in 2019, the lake rose to nearly 80% of its flood control capacity, placing immense pressure on the original 1948 gates.
Anthony Rodino (right), chief of the Programs and Project Delivery Branch for the U.S. Army Corps of Engineers Nashville District, briefs Col. Herlihy (left), commander of the Great Lakes and Ohio River Division, during a tour of Center Hill Dam in Lancaster, Tennessee, Feb. 19, 2026. Rodino provided an overview of the dam’s operations and the status of the spillway gate replacement project. The U.S. Army Corps of Engineers Nashville District is replacing spillway gates at Wolf Creek Dam in Jamestown, Kentucky, and Center Hill Dam in Lancaster, Tennessee, to upgrade its flood risk and water management infrastructure in the Cumberland River Basin. In this photo, spillway gates are assembled on a barge at Center Hill Dam Feb. 19, 2026. USACE PHOTO BY NOE GONZALEZ
The gates, which have exceeded their design life, urgently needed replacement. The project will ensure the safety of the public downstream for years to come. The new, heavier gates require modernizing the original lifting equipment. By utilizing a unique collaborative dynamic with the contractor, lessons learned are being transferred in real-time between various district projects to enhance efficiency.
Mega-Project Progress at Chickamauga
At Chickamauga Lock, the focus shifted to a mega-project that will dramatically improve efficiency on the Tennessee River. The new 110-by-600-foot lock is designed to reduce commercial transit times by an estimated 80% and increase capacity nine-fold.
Massive miter gates are stacked inside the new 110-by-600-foot lock chamber at the U.S. Army Corps of Engineers Nashville District’s Chickamauga Lock Replacement Project in Chattanooga, Tennessee, Feb. 20, 2026. Crews are currently in the process of installing and welding the 14 new gates, a critical phase in the construction that will ultimately lead to an 80% increase in navigation efficiency on the Tennessee River. USACE COURTESY IMAGE
“TVA is the owner of the locks, but USACE is a very proud partner… a very strong and effective relationship,” said Adam Hale, Nashville District project manager. Hale detailed the immense economic impact of the waterway, noting that over 40 million tons of commodities pass through these locks annually. “It is not just about moving products through the river. It is about empowering the economies and improving lives up and down this Tennessee River.”
Investing in People
Throughout his visit, Herlihy emphasized that the strength of the Corps lies in its people. He recognized multiple team members throughout his visit, presenting them with division coins for their noteworthy contributions. Lt. Col. Guillermo Guandique, Nashville District commander, noted that having senior leaders engage directly with subject matter experts builds confidence across the entire organization.
Col. Herlihy, commander of the Great Lakes and Ohio River Division, poses for a group photo with U.S. Army Corps of Engineers Nashville District leaders, project managers, engineers, and specialists in front of newly assembled spillway gates at Center Hill Dam in Lancaster, Tennessee, Feb. 19, 2026. The team briefed the commander on the progress of the major gate replacement project during his tour of the facility. USACE COURTESY IMAGE
Members of the project delivery team for the Chickamauga Lock Replacement project gather for a group photo on a construction barge. The team includes U.S. Army Corps of Engineers personnel and project contractors.
Lt. Col. Guillermo Guandique, commander of the U.S. Army Corps of Engineers Nashville District, briefs Col. Herlihy, commander of the Great Lakes and Ohio River Division, during a tour of the Chickamauga Lock Replacement Project in Chattanooga, Tennessee, Feb. 20, 2026. Progress on the multi-contract project includes the new lock chamber at 76 percent completion and the upstream approach wall at 70 percent, with the final contract awarded in February. The new 110-by-600-foot lock will process nine jumbo barges in one lockage, compared to one in the existing lock, an 80% increase in efficiency for the navigation industry. USACE COURTESY IMAGE
A USACE officer provides a briefing during a site visit to the Chickamauga Lock Replacement project. The background shows large red cranes and the Tennessee River landscape.
Cayce Grall, project manager for the U.S. Army Corps of Engineers Nashville District, briefs Col. Herlihy, commander of the Great Lakes and Ohio River Division, during a tour of the Chickamauga Lock Replacement Project in Chattanooga, Tennessee, Feb. 20, 2026. Progress on the multi-contract project includes the new lock chamber at 76 percent completion and the upstream approach wall at 70 percent, with the final contract awarded in February. The new 110-by-600-foot lock will process nine jumbo barges in one lockage, compared to one in the existing lock, an 80% increase in efficiency for the navigation industry. USACE COURTESY IMAGE
Josh Munzek (left), project manager for American Bridge Company, briefs Col. Herlihy, commander of the Great Lakes and Ohio River Division, on the status of the spillway gate replacement project at Center Hill Dam Feb. 19, 2026. The discussion took place on a barge where new gates were being assembled and welded for future installation. USACE COURTESY IMAGE
U.S. Army Corps of Engineers subject matter experts and leaders, along with a contractor from American Bridge Company, show Col. Herlihy, commander of the Great Lakes and Ohio River Division, a close-up view of the spillway gates from inside the Pier 1 access hatch at Center Hill Dam in Lancaster, Tennessee, Feb. 19, 2026. The tour provided Herlihy with a detailed, firsthand perspective on the ongoing spillway gate replacement project. The U.S. Army Corps of Engineers Nashville District is replacing spillway gates at Wolf Creek Dam in Jamestown, Kentucky, and Center Hill Dam in Lancaster, Tennessee, to upgrade its flood risk and water management infrastructure in the Cumberland River Basin. USACE PHOTO BY NOE GONZALEZ
Personnel from the U.S. Army Corps of Engineers and contracting partners perform an internal inspection of the structural features and maintenance walkways at the Chickamauga Lock project site.
Col. Herlihy, commander of the Great Lakes and Ohio River Division (right), presents a division coin to David Darling, a safety specialist for the U.S. Army Corps of Engineers Nashville District, during a tour of the Center Hill Dam in Lancaster, Tennessee, Feb. 19, 2026. Darling was one of several team members nominated by supervisors and recognized by Herlihy during his visit for their outstanding contributions and commitment to excellence. USACE COURTESY IMAGE
As for his own priorities, Herlihy kept his message simple and direct. “My priorities are to continue to deliver, and to take care of each other. If we do those two things, we’re winning.”
Frequently Asked Questions: Great Lakes and Ohio River Division
Why are spillway gates replaced?
Spillway gates at dams like Center Hill have a specific design life. Over decades, structural members can deform due to age and extreme pressure. Replacing them ensures that the dam can continue to manage floodwaters safely.
What is the relationship between USACE and TVA?
On the Tennessee River, the Tennessee Valley Authority (TVA) is the owner of the dams and locks, while the U.S. Army Corps of Engineers operates and maintains the navigation locks through a strong federal partnership.
What is a “mega-project” in USACE terms?
Mega-projects, like the Chickamauga Lock replacement, are large-scale, high-cost construction efforts that have significant national or regional economic impacts and require complex engineering and long-term planning.
