FARGO, N.D. - Fargo's fears of a catastrophic flood eased yesterday with word that the Red River apparently crested at lower-than-expected levels, and weary residents turned their attention to ensuring their hastily built levees hold up against an onslaught of ice-laden water expected to stay high for at least a week.
National Weather Service meteorologist Mike Hudson said the Red River began receding yesterday morning, surprising residents who were bracing for a crest today. But the river can still fluctuate up to a foot and may remain at dangerous levels for a week, meaning people will still have to wait several days before they are completely safe.
"The best news we can take from this is, the river has crested," Mayor Dennis Walaker said. "But diligence is going to have to be required for at least eight more days and hopefully things will continue to drop."
Forecasters say the river is retreating because cold weather has been freezing water that normally would be flowing into the river. By the time that water thaws, the biggest flooding threat is likely to have passed, Hudson said.
The weather service said the river crested about midnight local time at 40.82 feet. As of 5:15 p.m., it had dropped to 40.53 - still more than 20 feet above flood stage, but a significant shift from earlier forecasts that predicted the river would crest as high as 43 feet - the same level as the dikes protecting Fargo.
Despite the revised forecast, officials did not back down in their efforts to fend off the floodwaters, deploying high-tech Predator drone aircraft, calling up more National Guard troops, and asking residents to form neighborhood patrols to look for any breaches in levees.
Walaker and other officials have made it clear that they welcomed the extra help from residents to monitor the sandbag dikes hastily assembled to protect the city of 92,000 - while remaining confident that residents could make it out of town at the last minute if they had to.
"It's critically important that we're vigilant in inspecting those levees to ensure they're stable," city engineer Mark Bittner said. "We encourage neighborhoods to get together and have their own dike patrols and assist us."
Such efforts were playing out across Fargo after a week in which residents worked tirelessly to fill sandbags and build up the miles of levees protecting the city. Residents were asked to look for signs that dikes may be taking on water and to call authorities if they saw a problem.
Bruce Boelter walked the entire length of a roughly mile-long stretch of sandbag dike to eyeball the wall separating his subdivision and the Red River. Neighbor Tony Guck joined him halfway. Each felt a special stake in the dike they helped build.
"If we don't protect this, it's going to get us," Guck said. "It's basically for our own security. I'm just planning on coming out every six hours and walking it."
The flooding has forced hundreds of residents in the Fargo area from their homes and submerged basements and ground floors in an untold number of houses along the river. Emergency crews in boats had to rescue 120 people from their homes in one community north of Fargo, while about 20 percent of households in neighboring Moorhead, Minn., have been urged to leave.
The flooding was brought on by heavier-than-average winter snows, spring rains, and a rapid thaw of the snowpack that sent the Red River to record-high levels in Fargo, North Dakota's largest city.
A winter storm was predicted to hit North Dakota early this week, although the worst of the snow is expected to dissipate by the time the weather reaches Fargo. Still, wind from the storm could cause 2-foot waves that could send some water over the top of dikes, said Dave Kellenbenz, a meteorologist with the National Weather Service.
The variation in flood forecasts was a roller coaster throughout the week for Fargo, with the projection edging upward twice before being lowered yesterday. Walaker opened a briefing earlier in the day by apologizing for criticizing the weather service.
Greg Gust, a warning-coordination meteorologist for the weather service, said the predictions were complex. They come from round-the-clock work by hundreds of scientists, engineers, and other experts. Some of them brave the river for measurements of volume, flow, and temperatures. They also use computer models for mathematical and statistical analyses.
But even with improved forecasting methods, the river's record levels and the volatile temperatures do not allow anyone to be certain, and the weather service continued to hedge its prediction.
"The relative uncertainty in forecast models remains and the river will continue to behave in ways never before seen," the weather service said.
The main focus for the Fargo area will be on whether the long line of levees will be able to hold up - regardless of the water's level. Engineers say that whenever water is pressed up against a levee for a considerable period, there is a risk of catastrophic flooding.
"The saturation usually becomes the enemy of a levee over time," said Jud Kneuvean, chief of emergency management for the Army Corps of Engineers in Kansas City. "It can cause the embankment to be less stable and slide."
Officials said they were increasing the number of National Guard troops from 1,700 to 1,850 and bringing in hundreds of large bags that hold a ton of sand and that could be dropped by helicopter into breaks in the levees.
Predator drones began flying yesterday morning, providing military-style surveillance and allowing authorities to react quickly if flooding worsens.
President Obama assured the nation yesterday that he was keeping close watch on the floods and putting the government's full weight behind efforts to prevent disaster.