OMAHA, Neb. (AP) — The Fort Calhoun nuclear power plant that was entirely surrounded by Missouri River floodwaters earlier this summer officially ended its flood emergency Monday afternoon, utility officials said. But the power plant about 20 miles north of Omaha will remain shut down until repairs are made and regulators approve restarting the facility, Omaha Public Power District spokesman Jeff Hanson said. The river near the plant fell to 1003.5 feet above sea level Monday. The main power plant buildings are at 1,004 feet above sea level.

At the height of the flooding, the Missouri River rose up to 1,006 feet above sea level. That forced OPPD to erect a network of barriers and set up an assortment of pumps to help protect its buildings. But the plant remained dry inside, and officials said Fort Calhoun could withstand flooding up to 1,014 feet above sea level. Workers have already begun removing some flood barriers and disassembling the elevated catwalks workers used to cross the flooded parking lot. Fort Calhoun has been shut down since April because it was being refueled before the flooding began. It’s not clear when it will restart because officials haven’t been able to determine what repairs are needed. The plant may reopen sometime this fall, but it could even be delayed until next spring depending upon repairs, inspections and the weather.

The utility has submitted a recovery plan to the Nuclear Regulatory Commission, and regulators must approve the plan for inspections and repairs at Fort Calhoun. NRC officials have promised to closely monitor the efforts to ensure the plant is safe and doesn’t represent a threat to the public. For Calhoun entered the low-level emergency status called a “notification of unusual event” because of the flooding on June 6. The status was officially lifted Monday at 1:42 p.m.

The Missouri River’s floodwaters have begun to recede but the river may not return to within its banks until sometime in September or October. There has been flooding along the river since June because the U.S. Army Corps of Engineers has been releasing massive amounts of water into the river to deal with unexpectedly heavy spring rains and mountain snowpack.