Updated

Fargo residents came together at churches Sunday and prayed they would be spared the Red River's wrath as water burst a levee and swamped a school, providing a powerful omen for the type of disaster that could strike at any time.

Church services that are a staple of life on Sunday mornings in Fargo took on greater significance as people gathered after a week of sandbagging, worrying and helping neighbors and prayed that their levees would keep holding the water back. They bowed their heads, sang hymns of hope and held their hands in prayer, and the mayor opened his morning briefing with a blessing.

The Red River continued its slow retreat Sunday after cresting a day earlier, dropping below record level to 39.71 feet. City officials have said they would breathe easier when the river falls to 37 feet or lower, expected by Saturday, meaning a lengthy test for sandbag levees that residents hastily constructed last week.

Fargo faces another test this week as a storm approached with up to a half-foot of snow and powerful wind gusts that could send ferocious waves crashing into and over the already-stressed levees.

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The sandbag effort resumed Sunday as helicopters began dropping 11 one-ton sandbags into the river to deflect its violent current and keep it from eroding vulnerable areas of the dike system.

A helicopter also was used to lower a 3,000-pound concrete weight onto an ice jam that was causing river levels to rise at Oslo, Minnesota, about 25 miles north of Grand Forks.

"They tried it, but there wasn't much success to it," Oslo city council member Scott Kosmatka said.

The aerial effort also included unmanned Predator drones used to watch flood patterns and ice floes and provide high-definition information to teams on the ground. North Dakota has more than 2,400 National Guard troops engaged in the flood fight across the state.

The helicopter sandbag effort was focused on an area of the river that put another scare in the city during the night when it burst past a levee and submerged a Lutheran school campus.

Oak Grove Lutheran Principal Morgan Forness said city officials, the Army Corps of Engineers, and the National Guard unsuccessfully tried to contain the gushing water after a floodwall buckled around 1:30 a.m. local time. The water kept spreading and "we couldn't contain it. ... it's inundating all of the buildings," said Principal Morgan Forness.

"The campus is basically devastated. They fought the good fight. They lost and there's nothing wrong with that," Mayor Dennis Walaker said. "Those things will continue to happen. I guarantee it."

Crews largely contained the flooding to the campus, preventing more widespread damage in nearby areas. School officials also frantically raced to rescue a cockatiel, parakeet and tortoises, birds, iguanas and snakes kept at the school as part of its science program, while pumping out most of the water in the buildings within 12 hours.

The flooding at the campus — heavily damaged in the region's 1997 flood — represented the type of disaster that could crop up in Fargo throughout the week, with Walaker calling it a "wakeup call" for the city.

"The main event is right now, while we have this higher water. And it ain't over till it's over," said Rep. Earl Pomeroy. "And it ain't gonna be over until several days from now."

The levee watch in Fargo was one of several fronts in the fight against the Red River. Public works officials were closely monitoring the situation to make sure that water and sewer systems remain safe and that raw sewage doesn't back up into homes. Flooding statewide was blamed for two deaths, in central and western North Dakota, in what health officials said were apparent heart attacks brought on by flood-prevention exertions.

Moorhead, a city of 30,000 directly across the river in Minnesota, also was fighting to hold back the river. A husband and wife had to be rescued by boat from their home just south of the city after they became trapped on the second floor, said Clay County Sheriff Bill Bergquist.

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