Watts Bar Lock Preventive Maintenance Completed

The Nashville Engineer District’s maintenance support team, on board the mv. Iroquois, recently made repairs to the Watts Bar Lock on the Tennessee River.

The work, which was on the needle-dam-girder beam slot on the downstream end, began January 18 and was completed by January 26.

Lockmaster Gary Fleeman said the repair team and Watts Bar’s maintenance crew worked together to add armor plating to prevent concrete loss in the slot that is used whenever a beam is installed to pump water out of the lock chamber for maintenance.

“Due to the location, we could not have performed this repair without assistance from the maintenance support team,” Fleeman said. “We had to remove the slot filler that weighs approximately 6,500 pounds, so the use of the floating crane is essential.”

The crane supports mission needs of the Nashville district when it is not feasible to bring in the Regional Repair Fleet for minor work, Fleeman said.

The concrete on the downstream side on the needle-dam-girder beam slot did not originally have armor plate. Over the past 81 years that the lock has been in service, there has been concrete loss due to minor barge impacts, and that had exposed the slot filler locking pin sleeves, he said.

“Due to the location in the downstream approach, we needed a crane that was on a barge to lift the old slot filler out to make the repairs to the concrete and install a new piece of armor plate, then install a new slot filler,” he said.

Watts Bar Lock’s chamber is 360 feet long by 60 feet wide. Locking through requires a 59-foot lift from Chickamauga Lake to Watts Bar Lake. Construction of Watts Bar Lock started July 1, 1939, and it went into permanent operation February 16, 1942. The Nashville District operates and maintains the navigation lock at the Tennessee Valley Authority project.

Lee Roberts, public affairs specialist for the Nashville Engineer District, contributed to this report.