Flood Facts and Information

NPPD is taking measures necessary to protect the public’s health and safety, while continuing to provide reliable electric service. One part is ensuring that NPPD’s power generation plants across the state continue to operate as planned.


Although NPPD’s Cooper Nuclear Station (CNS) is elevated 13 feet above the natural grade to an elevation of 903 feet mean sea level as part of its design against flooding from the Missouri River, plant operators continuously monitor the increasing levels and water flows.  River levels are rising, as water from heavy rains the past few weeks, and elevated Platte River flows due to higher than average snow melt, feed into the Missouri River. However, river level conditions only require monitoring at this point. For plant operation and public safety, NPPD takes the following proactive measures:

  • When levels reach >895’ – or they are expected to be > 902′ within 36 hours – Cooper follows a special procedure specific to anticipated flooding conditions.
  • At 896’, the Brownville Road is impacted and may be closed. If so, plant workers detour through the city of Nemaha.
  • If the river reaches 898’ Cooper begins following an additional procedure which involves installing primary flood barriers.
  • Should the river reach 899’ NPPD would determine it a Notification of Unusual Event, which is the lowest of four emergency classifications.
  • At 900’ we would install secondary flood barriers.
  • If the river reached a level of 902’, Cooper would enter an ALERT emergency classification.


As of today/Thursday the river level at Cooper today is/was 894.2.

For historical perspective, Cooper has withstood past flooding conditions. In 1993 and 2011, river levels increased to 901’. In 2008, the river crested at 896’ and 899’ in 2010.

The National Weather Service hosts information on river levels and a conversion chart is available, should you want to compare sea level to feet.


  • Cooper Nuclear Station has an emergency response plan that includes periodic drills, role-plays of mock scenarios to practice that emergency response plan.


  • Among the total 104 reactors in the U.S., Cooper is one of thirty-five Boiling Water Reactors (BWR).
  • Cooper’s General Electric BWR-4 design is enhanced or modified to include:
    • Steam-driven coolant pumps that operate independently from AC power.
      • Station batteries are used for automatic operation.
      • Procedures are in place to manually operate without DC power.
  • All safety-related equipment is protected from tornadoes and external flooding events.