TVA Dams and Waterways
Preparations for a New Madrid Fault Disaster and
Other Seismic Events

TVA River Operations Dams

Infrastructure Description
 Of the 49 dams that TVA owns and operates:
 10 have navigation locks
 14 are concrete dams
 12 are combined concrete/embankment
 23 are earth or rock filled embankment
Ocoee 2 Diversion Dam (Timber Crib), TN

Dam Safety in TVA
• TVA operates its Dam Safety Program in accordance with the FEMA for Dam Safety .
Federal Guidelines
• The Guidelines identify 3 hazard potential classifications for dam failure: o Low—no LOL, minor property damage o Significant—no LOL, environmental, economic, and other damages o High—LOL
• Scheme does not incorporate range of downstream consequences.

Down-Stream Consequences
Study
2007 Study addresses other factors and weights such as PAR, property damage, power generation, navigation, reservoir volume, etc.
• Identifies and prioritizes communities at risk.
•Developed a more refined consequence classification.

Seismic Hazard Assessment
• Completed assessment in 2007
• Predicted ground motion levels using different return periods at each dam.
• Use this ground motion to evaluate dams and determine required modifications.

Down-stream Consequences +
Seismic Hazard Assessment
•
Gives better picture of risk
•
Prioritize evaluations
•
Prioritize modifications

Instrumentation Dam
Monitors
• Hw & Tw changes.
• Dam structure movement.
• Hydraulic changes inside dam.
• Change in seepage
• Earthquake ground motion
Chatuge, GA

Dam Safety Emergency
Action Plan
• Outlines what TVA will do in case of a dam safety event.
• Emergency notification process.
• Inundation maps.
• County EMAs have copy.

Waterway Management Plan
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