The picture says it all...

A monster flood could knock out the power in this essential raw cooling water building at Sequoyah Nuclear Plant, so TVA has added new conduit seals and door seals for added protection. In other plant areas, concrete and steel barriers protect more critical equipment and some parts, like deisel generator fill pipes, have been elevated.


TVA admits mistakes to NRC in calculating flood, natural disaster risks
[link to www.timesfreepress.com]

[snip]

TVA officials were squirming a bit Monday and a few cheeks glowed pink at times as directors and inspectors with the Nuclear Regulatory Commission plied them with questions about protecting Watts Bar and Sequoyah nuclear plants from a future monster flood.

TVA spent much of the five-hour Atlanta meeting with NRC acknowledging the utility's mistakes in making flooding calculations and owning up to a culture of complacency about potential natural disasters.

TVA officials said the continuing heartbreak of Fukushima gave them new resolve to harden safety at Watts Bar and Sequoyah, where new weather and flooding models show a monster flood could send water nearly two and a half feet higher than expected at Sequoyah Nuclear Plant and more than four feet higher at Watts Bar Nuclear Plant. Such a rise could threaten electric connections for critical reactor cooling equipment.