The danger of a flooding related problem outweighs the need.
http://www.nppd.com/flood/powerplants.asp
If Cooper Nuclear Station is shutdown due to flooding, will NPPD be able to meet its customer demand for electricity? Yes, NPPD relies on a diverse mix of power plants across the state to generate electricity. These power plants use a variety of fuel types ranging from nuclear, to coal, natural gas, hydro, oil, wind and solar. Each of these generating plants also provide a different level of electricity output, but are used in combination to serve customers electricity needs in NPPD's service area. If Cooper Nuclear Station is shutdown, NPPD will rely on generation from another operable power station. Depending on price, NPPD may choose to start-up or increase the output of one of its other generating plants or purchase the energy from the wholesale power market.