Flood preparations were underway this week on Prairie Island where officials are closely monitoring rising river levels.

Dozens of volunteers were filling and stacking sandbags Tuesday, March 19, with more sandbagging events planned for Wednesday and Thursday. Prairie Island Police Chief Jon Priem said work also began last week on an 11-foot-tall sand berm behind the Treasure Island Amphitheater.

The Mississippi River level at U.S. Lock and Dam No. 3 was 673.68 feet as of Tuesday morning, according to data reported to the National Weather Service. Projections have the river nearing 678 feet by Monday night, March 25 - just a couple feet shy of the flood stage of 680.5 feet.

“We’re not expecting the worst, but we’re planning for the worst,” said Schyler Martin, Prairie Island Indian Community emergency management coordinator.

Martin provided a flood planning update Tuesday to Prairie Island employees, including the “trigger points” for evacuation off the island. A voluntary evacuation would be issued when the forecast predicts river levels of 683 feet, he said. A forecast of 685 feet would trigger a mandatory evacuation.

“We want to hit the brakes before we have the accident,” Martin said. “When the forecast suggests we’re going to start hitting those levels, that’s when we’re going to start taking those actions.”

An area of concern is Sturgeon Lake Road, which gets washed out at around the 685-foot water level. The road serves as the main roadway on and off the island.

Prairie Island is home to about 250 people. Hundreds more people also come daily to visit or work at Treasure Island Resort and Casino and the Prairie Island nuclear plant. Prairie Island Indian Community has been in contact with government agencies and Xcel Energy to coordinate the flood response, Martin said.

Treasure Island Resort and Casino is at an elevation of 692 feet.

History of flooding

February 2019 set multiple snowfall records around the region, prompting fears of a particularly bad spring for flooding. High temperatures nearing 50 degrees this weekend could cause a rapid snowmelt.

Flooding is a yearly occurrence for Prairie Island Indian Community, but some residents still recall the historic flood of 1965. Tribal Council Vice President Lucy Taylor said she remembers gathering her belongings and going on boats to safety.

"What I most remember is the grandmothers being scared to death to get in the boats because they had never been in boats," Taylor said of the 1965 flood that saw the river crest at more than 687 feet.

The river reached 682 feet in June 2014.

The state has flood safety and planning information at http://mn.gov/mmb/be-ready-mn/weather/floods.