Nuclear, O&M, Reactors

Ft. Calhoun nuclear plant prepares for potential flooding

The 500-MW Fort Calhoun nuclear power plant shut down early Friday morning after the nearby Missouri River was expected to rise above safe operating levels.

The National Weather Service predicts that the Missouri River will exceed 1,004 feet above mean sea level Friday night. The river level is currently at 998-feet, 3-inches and rising approximately 0.5 inches per hour as of the morning report with the U.S. Nuclear Regulatory Commission. Plant operator Omaha Public Power District (OPPD) began plant shutdown to hot standby and will proceed to cold shutdown within 36 hours following hot shutdown, as required. The reactor will remain shutdown until the level of the river remains below 1,004 feet, which OPPD said in a release it expected the river would stay below that level.

Fort Calhoun shut down in April 2011 for a refueling outage. The Missouri River flooded the following June, and the reactor remained offline during the flood. A fire and several violations kept the reactor offline until the NRC approved its restart in December 2013.

OPPD said it was closely monitoring river levels and proactively preparing in case water inundates the plant, which includes reviewing plans and lessons learned from the 2011 flood and having sandbags, sand and a sandloader on site. Temporary berms have been erected around critical equipment.

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