The mv. Thelma Parker II takes the first tow into Demopolis Lock May 16 after the lock reopened following a four-month closure. (Photo courtesy of Mobile Engineer District)
Locks and Dams

Demopolis Lock Reopens After 4-Month Closure

Four months to the day after the upper miter sill failed at Demopolis Lock on the Tombigbee River, the lock reopened to navigation May 16, roughly two weeks ahead of the Mobile Engineer District’s initial forecast.

The failure took place January 16 when a 600-ton piece of the upper miter sill broke off and crashed to the floor of the lock chamber below. On January 19, Parker Towing Company maneuvered three boats—the mvs. Gilbert Taylor, Charles Haun and Thelma Parker II—into the lower approach to assist lock operators to safely close the lower miter gates. With the lower gates closed, the Corps set stop logs at the upper end on January 20.

During the months that followed, Corps officials worked with engineers at the U.S. Army Engineer Research and Development Center (ERDC) to approve cement formulas that allowed the Mobile District’s maintenance contractor, R&D Maintenance, and subcontractors to conduct some of the concrete pours “in the wet.” McKinney led the debris removal effort, while Brennan, Cemex and Ready Mix USA were the lead subcontractors for the repair effort.

As the seven concrete pours progressed, weather conditions helped curing times speed along, thus allowing the Corps to conduct performance tests ahead of schedule, demobilize equipment and, ultimately, reopen the lock around 4:30 p.m. May 16.

As it turned out, one of the Parker Towing boats that helped close the lower gates in January was the first through the lock on May 16.

“As we speak, the Thelma Parker II is locking through Demopolis,” said Wynne Fuller, president of the Warrior-Tombigbee Waterway Association, at the conclusion of day one of his organization’s annual conference.

Speaking at the Warrior-Tombigbee conference, Nelson Sanchez, operations division chief for the Mobile District, asked representatives from the Corps, industry and contractors involved in the Demopolis repairs to stand up and be recognized.

“Without them all working together, we would have never made today as the opening,” Sanchez said.

Anthony Perkins, project manager for the Black Warrior-Tombigbee Waterway, which includes Demopolis Lock, offered conference attendees an overview of the repair work. The Corps was able to place debris removed from the lock in a washout area nearby, he said. Perkins also shared a time-lapse video that spanned from when preliminary work started in the chamber to completion of the new upper miter sill.

Perkins emphasized that the lock chamber is now 602.9 feet long, down from 604.9 feet. In addition, the sill goes straight across the chamber, rather than being in a chevron shape as before. A yellow line on the lock wall marks the location of the sill.

“It’s not really a new locking procedure,” Perkins said, “but it’s a new emphasis on safety.”

Col. Jeremy Chapman, commander of the Mobile District, said the failure and successful repair efforts at Demopolis highlight the risk associated with the nation’s aging infrastructure, including its waterway infrastructure. Chapman said Corps officials are pushing for a “Major Rehabilitation Evaluation Report,” which would assess the risk of failure across the system and set a framework for tackling major rehab projects.

Chapman said the emergency response-type approach at Demopolis, including fully funding repair work, could be model for rehab work throughout the nation.

“Like you saw in Demopolis, when we get the money, and the people and partners are all moving in the same direction, it happens,” he said.

Caption for photo: The mv. Thelma Parker II takes the first tow into Demopolis Lock May 16 after the lock reopened following a four-month closure. (Photo courtesy of Mobile Engineer District)