Pickwick Landing Dam South Embankment Seismic Upgrade Project

After a 2014 analysis of the Pickwick Landing Dam showed that the dam’s south embankment could face potential damage in a larger seismic event, the Tennessee Valley Authority (TVA) started making plans to stabilize the south embankment to meet dam safety criteria. Built during the 1930s, the Pickwick Landing Dam was constructed to produce hydroelectricity, provide flood control, and improve the navigability of the Tennessee River. As part of this project, Barnard performed work on the upstream and downstream portions of the dam, including construction of large buttresses, extended fills, and a new toe drain system.

The downstream portion of the project included dewatering; excavation; performing instrumentation modifications; constructing manholes, catch basins, and a new toe drain; placing a filter system and fill; and placing riprap for slope stabilization. Prior to performing excavation on the downstream side of the dam, Barnard dewatered the soils while complying with TVA’s requirements for drilling in embankments. To complete this, Barnard drilled and installed deep wells using sonic drilling methods. Work on the upstream portion of the dam consisted of constructing a large rock berm and extended fill in the wet from barges in water depths up to 30 feet. Overall, this project required more than 1.9 million tons of import fill, sand, aggregate, and large rockfill materials.

Pickwick Landing Dam South Embankment Seismic Upgrade Project