NASHVILLE, Tenn. (July 27, 2015) – If you dig history, you’ll love how engineers excavated nearly 100-million dump truck loads of soil to connect the Tennessee and Tombigbee Rivers, opening a new passageway to the Gulf of Mexico in 1985.
As the U.S. Army Corps of Engineers Nashville District celebrates its 130th Anniversary in 2018, the organization is highlighting various projects that developed the region’s waterways for flood risk reduction and navigation, including the historic role the district played in building the largest civil works project ever constructed in the United States.
According to the book “Engineers on the Twin Rivers” by Dr. Leland R. Johnson, before the Corps of Engineers constructed the Tennessee-Tombigbee Waterway, a navigable inland water route from Mobile Bay up the Alabama and Tombigbee rivers to Columbus, Miss., “abruptly ended a few maddening miles from the Tennessee River.”
When the Tennessee-Tombigbee Waterway opened in 1985, it established a southern route from the Tennessee River that shortened the journey from Muscle Shoals to New Orleans via the Mississippi River from 1,121 miles to 647 miles on the new waterway, Johnson wrote.
President Richard M. Nixon and Alabama Gov. George Wallace participated in the groundbreaking for the construction of the waterway May 25, 1971. The Mobile and Nashville Districts built the 234-mile waterway from 1972 to 1984.
The Mobile District constructed the southern 195 miles of the waterway, including nine locks and dams. The team from Mobile handled what was known as the “River” and “Canal” sections of the project. The Nashville District excavated the northern 29 miles of the project, including the massive 27-mile divide cut, which connected the waterway with Pickwick Lake on the Tennessee River, and constructed Bay Springs Lock and Dam in Dennis, Miss. Congress renamed the project the Jamie L. Whitten Lock and Dam June 6, 1997 in honor of the former U.S. representative who greatly supported the construction of the waterway.
The Corps excavated nearly 310 million cubic yards of soil during the 12-year project. In comparison, 210-million cubic yards of earth were removed from the Panama Canal.
Tom Cayce, who retired as the deputy chief of Planning, Programs and Project Management for the Nashville District in 2011, spoke about the waterway at the dedication of the Tennessee-Tombigbee Waterway Transportation Museum in Columbus, Miss., Feb. 6, 2015.
Cayce said during the construction, he mostly helped with environmental aspects in planning and with budgetary documents and requests in support of the project.
“It was the number one project in our district as well as the Mobile District too,” Cayce said.
Don Waldon, administrator of the Tennessee-Tombigbee Waterway Development Authority from 1984 until his retirement in 2005, also attended the museum dedication and recollected about the project being the first large one to be constructed in accordance with the provisions of the National Environmental Policy Act of 1969.
“As a result of that, we were sued twice essentially by railroads that were opposed to the waterway because of being a competitive mode,” Waldon said.
The project weathered the litigation as well as political and environmental opposition. Ultimately, design changes accommodated environmental quality as mandated by NEPA.
Waldon stressed that the Mobile and Nashville Districts were able to coordinate and obligate more than $100 million each year, a huge amount in the 1970s and 80s, and complete the waterway in 12 years at a total cost of $2 billion.
Mike Zoccola, professional engineer and former chief of the Nashville District’s Civil Design Branch, retired from the Corps in 2016, but served as a young design engineer during construction of the waterway and worked on plans and specifications of excavation contracts for the divide cut. In a 2015 interview, he said the divide cut was the high point separating the two river basins and there were some fairly large and deep cuts that proved challenging.
“The materials were problematic,” he explained. “The real problem was the stability of the slopes from an erosion standpoint, because it was sand. They tended to erode fairly quickly so getting vegetation established, riprap stabilizing disposal areas - that was a big concern at the time. We had a lot of large drainage structures carrying tributaries into the cut at that time during some floods that actually washed out. It was an ongoing challenge for us.”
Zoccola added that he would travel to the construction sites every few weeks, but at the time did not fully appreciate the project’s historical significance.
“But I did know at the time it was one of the largest civil works projects ever undertaken by the Corps of Engineers. It’s a pretty massive undertaking so I did appreciate that fact,” Zoccola said.
Mike Wilson, former deputy for Programs and Project Management in the Nashville District, retired from the Corps in 2017, but worked as a student coop and helped calculate the amount of concrete needed for various options being considered at the time to build the navigation lock at Bay Springs. In a 2015 interview, he noted that he also designed one of the lock’s monoliths.
“I began working for the district in August of 1975 and they were deep into the planning and design of the Tenn-Tom Waterway,” Wilson said. “And my first assignment, the very first day I started work, was to check the coordinates with the Mobile District alignment and the Nashville District alignment to make sure they intersected at the right spot. My calculations showed them to be six inches off, which for earth work was close enough. That was my very first assignment so the Tenn-Tom is very near and dear to my heart.”
Wilson said he also checked shop drawings of the drainage control structures in the divide cut for quality assurance and learned a lot about concrete design and reinforcement detailing.
“There was a lot of earth movement,” Wilson recalled, “so there were a lot of big disposal sites… so there was a lot of work to make sure that the area left intact was environmentally friendly.”
Wilson added that the Nashville District used a new engineering technique at the time to anchor the lock walls into the rock wall, a method that saved in the cost of its construction.
Whitten Lock (formerly Bay Springs Lock) raises and lowers barges and pleasure boats 84 feet and is the fourth highest single lift lock in the nation. A series of culverts were constructed in the bottom of the lock to allow the chambers to empty or fill in about 20 minutes without any turbulence or whirl pools that might cause safety concerns for boats being locked.
When the Nashville District completed the dam it formed a 6,600-acre lake that joined the divide cut canal that connects with the Tennessee River.
In the end, the two districts, 125 prime contractors and 1,200 subcontractors worked on the overall waterway. The 10 locks and five dams required a total of 2.2 million cubic yards of concrete and 33,000 tons of reinforcing steel.
The Nashville District dedicated the 27-mile divide section of the Tennessee-Tombigbee Waterway and the Bay Springs Dam and Lock in Dennis, Miss., May 6, 1984.
Secretary of the Army John O. Marsh Jr. and Governor Wallace presided over the dedication of the entire waterway June 1, 1985 in Columbus, Miss., which symbolically merged the waters of 23 states and linked them to the Gulf of Mexico.
(The public can obtain news, updates and information from the U.S. Army Corps of Engineers Nashville District on the district’s website at www.lrn.usace.army.mil, on Facebook at http://www.facebook.com/nashvillecorps and on Twitter at http://www.twitter.com/nashvillecorps.)