SAVANNAH ― The Tennessee Valley Authority announced Thursday that Pickwick Landing Reservoir will return to normal summer lake levels on schedule by mid-April, depending on rainfall.
During the next six weeks TVA will also install an early warning system to notify downstream residents should an earthquake occur that is large enough to damage the dam’s south earthen embankment.
While the dam is performing as designed, the water level at Pickwick was lowered to winter levels several weeks early last October so the embankment investigation and analysis could be completed.
“TVA and the industry are using more stringent criteria today to evaluate dams. This is
John McCormick, vice president of Safety, River Management and Environment
based on our modern-day understanding of how embankment dams constructed like Pickwick perform in large earthquakes,” said John McCormick, vice president of Safety, River Management and Environment. “Although the likelihood of a large, damaging earthquake is small, the safety of downstream communities, industries, the public and our employees is our top priority.”
Very large earthquakes such as those that occurred near New Madrid, Mo., in 1811 and 1812 would be of concern for the Pickwick embankment, McCormick said. That earthquake reached 7.5 on the Richter scale, according to the U.S. Geological Survey.
TVA is installing multiple layers of seismic detection equipment that will send a notification to TVA and the National Weather Service of any change in the embankment. If necessary, a notification for downstream residents to seek higher ground will be sent via the National Weather Service. Anyone with a weather radio in the vicinity of Pickwick Dam will receive an alert in case of damage to the dam due to a major seismic event. TVA will provide weather radios to downstream area residents this spring.
Beginning March 12, portions of Highway 128 will be blocked so that crews can install cables that will run the length of the embankment. The cables detect even slight amounts of movement. In addition, video and thermal cameras are being installed.
“This multi-layered system adds extra safety measures for those who live near this beautiful reservoir and enjoy the recreational and economic opportunities it presents,” McCormick said.
Installation of the early warning system is scheduled to be completed by early April.
TVA’s website and social media sites will provide up-to-date information about the Pickwick Dam project at www.tva.gov/pickwick, on Facebook at www.facebook.com/TVA and on Twitter at @TVA_Newsroom.
Pickwick Landing Dam was designed and constructed in the 1930s. The concrete portion includes the powerhouse, spillways and two navigation locks with long earthen embankments on each side. The south embankment is about 4,000 feet long.
MEDIA RELEASE/KATHY HODGES/ TVA Public Relations
