Some people in a western Iowa city are still out of their homes and businesses Thursday due to high water levels.

Missouri Valley Mayor Shawn Kelly estimates about 1,000 people in the city of close to 3,000 are affected. He says the evacuation was ordered Wednesday when officials suspected a nearby creek and a river could overflow.

According to the National Weather Service office in Valley, Nebraska, the Boyer River near Missouri Valley crested at 1,018 feet around 3 a.m. Wednesday, which is considered “approaching flood stage.”

Then, several local levees were breached Thursday morning, allowing more water to flood the city.

“We are currently monitoring the changes in the water,” Kelly said. “We’re also doing door-to-door evacuations and water rescues for citizens who did not heed the warning to evacuate.”

The National Weather Service said the mixture of the snow, rain and a rapid warm-up that melted snow from previous storms have caused "a once in a 20-year event."

Some residents have fled to a shelter in the city’s community center. Gerry Sue Rinella, a disaster responder for The American Red Cross, said they’re expecting at least 20 people to spend the night. Many more have been in and out for food.

“They can just sit and share their stories, or debrief with each other and kind of relax a little bit,” Rinella said.

Rinella said they have about 50 cots available for people to sleep on, an eating area and plenty of food. Some local eateries have donated food like chicken, sandwiches and donuts.

A lot of residents outside the evacuation area have also been helpful to those displaced, Kelly said.

“They’ve volunteered to open their doors for displaced people to come stay at their houses and whatever they need. The small community we have is a wonderful community that is helping everyone as best they can,” Kelly said.

It’s unknown how long the evacuation could be in place.

About 60 miles north, the city of Hornick in Woodbury County on Thursday morning told its 200 residents to evacuate after a levee broke along the West Fork of the Little Sioux River.

Gov. Kim Reynolds on Thursday afternoon issued a disaster proclamation, allowing 21 counties to use state resources to recover from flooding.