Demopolis Closure Likely To Last Until May

Demopolis Lock, located on the Tombigbee River just below its confluence with the Black Warrior River, has been closed since the morning of January 16, when the on-duty lock operator heard a loud “boom” and discovered that half of the upper miter sill had broken off and crashed onto the floor of the chamber.

Initially, officials with the Mobile Engineer District estimated repairs would take 30 to 60 days, but the Corps’ latest report has shifted the forecast reopening back to mid-May at best.

Rain in the region continues to cause water in the Tombigbee River to overtop stoplogs at the lock. With more rain in the forecast and the region entering its typical high-water season, the Corps has adopted a course of action that, while more lengthy, will nonetheless allow its maintenance team to work with fewer weather interruptions.

“They’re going to have to work in the wet and cast the concrete under water,” said Wynne Fuller, president of the Warrior-Tombigbee Waterway Association. “The chances for the lock being overtopped is really high, which is why they went with pour concrete in the wet.”

A floating plant on site will lower forms into the lock chamber, with assistance from divers. Those forms will be buttressed for stability, with buttresses anchored to the lock floor. Concrete forms will be poured in five-foot increments, with seven days required for curing between pours and a 14-day curing period after the final pour.

The Corps said a May reopening would also include all debris removal.

Repairs won’t result in a reduction in draft, but the length of the chamber will be marginally smaller, from 604 to 602 feet.

In the meantime, operators on the Tennessee-Tombigbee and Black Warrior-Tombigbee waterways who typically go to and from Mobile, Ala., are having to take the long way around via the Tennessee, Ohio and Mississippi rivers and the Gulf Intracoastal Waterway. A closure had been planned at Pickwick Lock on the Tennessee River, but the Nashville Engineer District is altering plans to keep the auxiliary lock open, with only short closures in the main chamber.

The Mobile District is hosting twice-weekly calls with waterway users to provide updates on the status at Demopolis Lock. Calls will be on Tuesdays and Fridays at 2:30 p.m. For more information, go to the Mobile District’s website, www.sam.usace.army.mil, and search for “navigation notices.”