As of Tuesday morning, the Big Sioux was hovering at about 18.9 feet, with flood stage being 16 feet for the area.

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"A considerable amount of farm land is flooded at this level, pushing 8,000 to 10,000 acres," said Mike Gillispie, hydrologist with the National Weather Service in Sioux Falls. "It would have to get to the 21 to 22 foot range before we'd see roads and highways impacted."

The Big Sioux, he said, was flooded from the Rock River junction downstream to just north of Sioux City.

Another system will move through the area in the next day that could bring more rain, Gillispie said. The National Weather Service predicts between 1 and 1 1/4 inch of precipitation will fall across the lower Big Sioux and Rock basins.

"If we get an inch, we'll probably see the Big Sioux be at or slightly below the level it was at Sunday." Gillispie said. "The worst is over for now, but we'll be watching to see how it plays out over the next week."