TVA Opens New Gates at Nolichucky Dam

A newly constructed spill gate at TVA’s Nolichucky Dam is allowing TVA to lower the reservoir behind the dam to conduct more thorough dam safety inspections.

JUNE 5, 2019 — In its first official implementation since installation in February, TVA recently opened a newly installed spill gate and successfully lowered the reservoir — in only 2 hours — more than a foot below the spillway crest elevation of about 1241 feet.  

“The new gate performed as expected and will allow us to look closely at this dam to ensure that it meets TVA standards for dam safety,” said Jim Bryant, senior program manager for Dam Safety.

A preliminary inspection of the face and toe of the dam was conducted while the water was down. Steep slopes and rocky shorelines limited access to the dam, but TVA Dam Safety utilized a high-tech amphibious vehicle (pictured above) loaded with Dam Safety sonar equipment to access the toe of the dam.  This equipment will provide more data and allow more extensive inspections in the future.

Nolichucky Dam was built in 1913 and acquired by TVA in 1945.  Located on the Nolichucky River just southeast of Greenville, Tenn., it impounds Davy Crockett reservoir. The dam stopped generating hydropower in 1972. After ongoing maintenance issues, its old spill gate had been permanently closed in 1995 by installing a reinforced concrete bulkhead on its upstream side.  

Today, TVA’s increased focus on dam safety calls for more thorough inspections, which is now possible by the new gate and other technological tools and machinery. The gate installation was a joint project effort between TVA’s Dam Safety, Environmental Compliance and Operations, Power Services Shops, and Generation Construction Projects Services & Facilities teams.

TVA also performs monthly, biannual and annual inspections of all of its river dams to identify any potential issues or concerns.  More thorough detailed inspections are performed every 5 years by a diverse team of dam safety subject matter experts, operators and inspectors. The inspections may also include testing of electrical and mechanical equipment, and rigorous structural and geological assessments. TVA has spent about $400 million since 2010 on Dam Safety. That includes current projects at Nolichucky, Boone, Pickwick and other sites.