The operator of the Cooper Nuclear Station issued a low-level emergency alert March 15 as water levels in the nearby Missouri River were rising a few days after a severe late-winter storm tore through the Midwest.
Officials had been monitoring the river's elevation rise for days following a combination of snowmelt and heavy rain as well as water being released from upstream reservoirs after the failure of the Spencer Dam on the Niobrara River near the Nebraska-South Dakota border, which caused damage to a hydroelectric plant.
There is no threat to plant employees or to public safety, the Nebraska Public Power District, the plant's owner and operator, said in a news release. Nonetheless, officials brought in thousands of sandbags and were taking additional measures to fortify the plant against the water.
NPPD spokesman Mark Becker said March 15 that the plant, near Brownville, Neb., might have to be taken offline over the weekend if water levels continue to rise to 45 feet, or 901.5 feet above sea level.
Early morning March 15, the district declared a "notification of unusual event," the lowest level of four emergency classifications as defined by the U.S. Nuclear Regulatory Commission, after the Missouri River reached 899.05 feet above sea level.
The plant, which came online in 1974, can generate up to 810 MW, which constitutes up to 35% of the power district's generating capacity to serve more than 94,000 retail and 6,000 wholesale electricity customers, according to Becker.
If the plant is taken offline, the power district will have to look to the Southwest Power Pool for more power supplies since the district's power plants are running "full tilt," Becker said.
The Southwest Power Pool would then look for the cheapest resources available to provide power to the district, he said.
In June 2011, flooding along the Missouri River also caused officials to issue a "notification of unusual event" at the Cooper Nuclear Station. That same flooding knocked Nebraska's other nuclear plant, the since-retired Fort Calhoun plant in Washington County, out of service for two-and-a-half years, costing its owner about $180 million in maintenance and capital expenses.
Currently, local forecasts call for water levels to start falling within days.