Concrete Sill Repairs At Demopolis Lock Are Nearing Completion

There’s light at the end of the lock chamber for stakeholders of both the Black Warrior-Tombigbee Waterway (BWT) and the Tennessee-Tombigbee Waterway (Tenn-Tom), with emergency repairs almost complete at Demopolis Lock on the Tombigbee River in east central Alabama.

Demopolis Lock, located just below the confluence of the Black Warrior and Tombigbee rivers, suffered a major failure of its upper miter sill on January 16. The failure triggered an immediate closure of the lock to navigation, which essentially cut off both the Tenn-Tom and BWT from the Port of Mobile, Ala., to the south.

The Mobile Engineer District partnered with R&D Maintenance, Brennan, Cemex, Ready Mix USA and McKinney Salvage & Heavy Lift to remove debris and execute repairs, which have included several cement lift pours “in the wet.” The Tennessee Valley Authority and Parker Towing Company also assisted in the early days of the closure.

The first concrete pour took place on April 11, and the seventh and final pour occurred on May 6.

“Everything’s looking good,” Anthony Perkins, operations project manager for the BWT, said during a stakeholders conference call May 8. “We had lift number 7 this Monday. That’s what finished us at the top.”

Perkins said the team on site has applied epoxy on the newly poured sill and mitered the upper gate in order to form the seal. Work remaining will include letting the cement cure, testing the cement, removing equipment from the chamber, fine-tuning the epoxy seal for the miter gate and painting the chamber wall to mark the new sill.

Prior to the upper miter sill failure, the lock chamber measured 604.92 feet long. The new sill, which extends straight across the chamber rather than in a chevron shape like before, reduced the chamber length by two feet to 602.92 feet.

“When you’re locking through, stay off the yellow line,” Perkins said. “The main thing is we want to stress the caution of the miter sill being straight across.”

On the May 8 call, officials with the Mobile District reiterated that they are 100 percent confident that the lock will reopen by May 30.

“We’re still about 75 percent for May 22,” said Nelson Sanchez, operations division chief for the Mobile District.

District officials plan to discuss the repair efforts at length during the Warrior-Tombigbee Waterway Association’s annual meeting, set for May 15-17 in Orange Beach, Ala. The Corps team likely still won’t be able to firmly commit to the May 22 reopening during the Warrior-Tombigbee meeting, since the final cement pour will still be curing at that time.

Sanchez said his team expects to be able to confirm a reopening date during the next stakeholder call, set for May 20.

“We’re hoping that will be the last one,” Sanchez said.

There hasn’t been anything easy about the closure from a logistics standpoint. Early on, some cargo owners opted to pay the extra price to send tows up the Tenn-Tom, into the Tennessee and Ohio rivers, then down the Mississippi to the Gulf Intracoastal Waterway in New Orleans. Of late, most people have chosen to wait out the closure. Still, industry officials on the May 8 call expressed their thanks for the hard work—and teamwork—that’s taking place at Demopolis.

“This has been a tremendous effort by the Mobile District, R&D and Brennan,” said Mitch Mays, president of the Tenn-Tom Waterway Development Council and administrator of the Tenn-Tom Waterway Development Authority. “I really appreciate all you’ve done. We’re waiting with bated breath.”