The Nuclear Regulatory Commission (NRC) said Jan. 5 that it is keeping an eye on heavy rains and flooding across the nation’s midsection and watching out for any adverse impacts on nuclear power plants located along the Missouri and Mississippi Rivers.
According to the National Weather Service, the threat of significant flooding is expected to persist for another two weeks in parts of Nebraska, Missouri, Arkansas, Mississippi and Louisiana – all states with operating nuclear power plants, NRC said in a Jan. 5 blog posting.
NRC offered the following rundown on the affected plants:
• In Nebraska, water levels are high along the Missouri River in the vicinity of the Omaha Public Power District (OPPD) Fort Calhoun and the Nebraska Public Power District (NPPD) Cooper Nuclear Station, but not high enough to require any mitigating actions by plant operators. Fort Calhoun was offline was about two years between 2011 and 2013 following a 2011 refueling outage that was extended due to record flooding, an electrical fire and significant performance issues.
• In Missouri, the Ameren (NYSE:AEE) Callaway plant is not expected to be affected by any of the heavy rains and flooding that have plagued other parts of the state.
• In Arkansas, the Entergy (NYSE:ETR) Arkansas Nuclear One, in Russellville, has not been affected by heavy rains and no impact is predicted. But some local roads that lead to evacuation routes were flooded, prompting local law enforcement officials to post detour signs.
• The Entergy Grand Gulf nuclear plant is located in Mississippi. Levels on the Mississippi River continue to rise, with a crest expected on Jan. 15, NRC said in the blog post. The projected river levels, however, are not expected to have any effect on site operations.
• At Entergy’s River Bend plant in Louisiana, the situation is similar. There, the Mississippi River level is expected to peak on Jan. 18, at a level that will not affect site operations. Further downstream, levels on the Mississippi River near the Waterford nuclear plant are expected to crest at a level two feet below where the operator would need to take some actions at the site.
“Each of these plants has emergency diesel generators that can supply backup power for key safety systems if off-site power is lost,” NRC said in the blog. “And all plants have robust designs with redundancy in key components housed in buildings with watertight doors,” NRC said.
Flooding is one of the many natural hazards that nuclear power plants must be prepared for As a condition of their operating license, every nuclear power plant must demonstrate the ability to withstand extreme flooding and shut down safely if necessary – requirements that have been updated and strengthened following the Fukushima accident in 2011, NRC said.