LANCASTER, Tenn. (July 28, 2025) – Work crews at Center Hill Dam removed the first of its massive spillway gates Saturday, a pivotal first step for an ongoing project to replace all eight original tainter gates and lifting equipment that have been in continuous operation since 1948.
The U.S. Army Corps of Engineers Nashville District and its contractor, American Bridge Company, slid the spillway gate on a platform where it could be picked up by a crane and placed onto a work barge located next to the dam on Center Hill Lake.
According to Mike Freeman, lead construction inspector for Nashville District’s Eastern Tennessee Resident Engineer Office, the contractor spent most of the day Friday cutting the spillway gate from the dam to prepare for its removal on Saturday. He said the lift on Saturday went smoothly despite some rainfall.
“It rained for about 10 minutes. It down poured as soon as they picked up the gate. When they set it down, the sun was shining,” Freeman said. “It went as planned. Lots of planning and engineering went into this gate removal and it was nice to see it in action.”
The successful extraction of the first spillway gate makes it possible for USACE to prepare the empty spillway bay for installation of the new spillway gate and lifting equipment.
“During construction, removal and installation of each gate, public safety is our top priority,” said Greg Bishop, Nashville District project manager. “This includes a new wire rope and drum setup, and replacement of high and low-speed gear boxes, 10 horsepower electric motor, bull and pinion gears, and the machinery base on each gate pier.”
Bishop added that the old lifting equipment had to be replaced due to the new spillway gates being heavier than the old ones as required by the project’s new design requirements.
Corps of Engineers’ water managers are maintaining lake levels within current parameters agreed upon with the Southeastern Power Administration. The public will not experience significant drawdowns of the lake elevation. The most distinguishable change to reservoir levels during the construction period, may be a lower peak summer pool from 648 feet to closer to 645 feet. This adjustment lowers project risk during construction while still falling within current operating targets.
Replacement is needed because a Spillway Radial Gate Evaluation Design Document Report in 2016 revealed the eight spillway tainter gates are subject to overstress due to trunnion friction issues. Trunnion friction is the force generated around the trunnion pin during a gate lifting operation. It is caused by the bearing of the trunnion pin against the gates’ trunnion hub and bushing, which is the rotating point of the gate.
Each spillway tainter gate is 37-feet high by 50-feet wide. The contractor is limited to three inoperable gates at any period of time, always leaving seven operable gates. As an additional risk reduction measure, only one gate bay will be open without a gate at any given time during construction. Replacement of gates will only occur between June and November each year, which is considered the dry season, targeting lower peak summer lake elevations.
The replacement of the spillway tainter gates and lifting machinery equipment will not affect the operation of the dam’s three hydroelectric generating units, which provide a total capability of 135,000 kilowatt-hours of hydropower.
USACE awarded the $91,250,000 contract for the Center Hill Dam Spillway Gates Replacement Project to American Bridge Company in September 2022. The project is fully funded by the Disaster Relief Supplemental Appropriations Act of 2022.
Center Hill Dam is located on the Caney Fork River in Lancaster, Tennessee. The dam forms Center Hill Lake, which covers parts of DeKalb, Putman, White, and Warren Counties. It controls the runoff from a drainage area of 2,174 square miles.
The public can obtain news, updates and information from the U.S. Army Corps of Engineers Nashville District on the district’s website at https://www.lrd.usace.army.mil/About/Districts/Nashville-District/, on Facebook at www.facebook.com/nashvillecorps and on X (formerly Twitter) at www.x.com/nashvillecorps. Follow us on LinkedIn for the latest Nashville District employment and contracting opportunities at https://www.linkedin.com/company/u-s-army-corps-of-engineers-nashville-district.
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