Fortunately this plant has been closed down for several months!

The Fort Calhoun Nuclear Station shut down in early April for refueling, and there is no water inside the plant, the U.S. Nuclear Regulatory Commission said. Also, the river is not expected to rise higher than the level the plant was designed to handle. NRC spokesman Victor Dricks said the plant remains safe.
Flood berm collapses at Nebraska nuclear plant - Qwest