Flood outlook worsens

By CHRIS VETTER

Journal Staff Writer

NEW ULM -- The chances of major flooding in New Ulm have worsened in the past two weeks, according to the National Weather Service.

Gary McDevitt, NWS hydrologist, unveiled the updated flood numbers Friday.

"The anticipated levels of flooding went up, and that's bad news," McDevitt said.

When the Chanhassen-based National Weather Service released flooding projections two weeks ago, those numbers did not include the two-day major snowstorm at the end of February. That storm not only packed a lot of snow but a lot of water content, McDevitt said.

"The main reason for the (flood projection) change is the snowstorm we had Feb. 24-25," he said. "The added moisture in the snowpack has caused the numbers to go up."

The Minnesota River as it weaves around New Ulm is considered to be at flood stage at 796 feet above sea level. The NWS has again projected a 100 percent chance of reaching 796 feet when the river crests in the first or second week of April.

Two weeks ago, the NWS said there was a 90 percent chance the Minnesota River will be two feet above flood stage (798 feet).

Friday, the NWS upgraded those conditions, saying there is at 98 percent chance the river will now crest three feet above sea level (799 feet).

The NWS predicts there is a 60 percent chance the river will reach five feet above flood stage and a 20 percent possibility that flooding will be seven feet above flood level.

The likelihood of flooding is much higher than just two weeks ago, when the NWS said there was only a 40 percent chance of water five feet above flood stage.

"I'm trying to raise a flag of warning so people can start to prepare," McDevitt said.

In 1997, the Minnesota River crested at 811 feet as it passed through town. McDevitt said there is still only a two percent chance the levels will reach that highmark again this year. That projection has not changed from the last NWS study.

"It's still a real remote possibility," McDevitt said.

McDevitt said his office will continue to monitor river flow and will release another flood warning on May 23.

Flooding projections also have worsened for the Cottonwood River as it snakes through rural New Ulm.

The NWS had previously said the Cottonwood River had a 30 percent chance of rising two feet above flood level and a 20 percent chance that it will exceed flood stage by three feet.

However, McDevitt said the situation has worsened. There is now a 70 percent chance the Cottonwood River will be two feet above flood level and a 40 percent chance it will be three feet above flood level.

Overall, there is a 98 percent chance the Cottonwood River will reach flooding stage, McDevitt said.

To avoid major flooding, the state must have moderate temperatures that slowly melt the snow.

"We need the continuation of warm days and cool nights to slowly melt the snow pack," McDevitt said. "We need 10-14 days of back-to-back above freezing days, below freezing nights."

McDevitt said the area would benefit from a dry March -- something he does not expect.

"We presume (the precipitation) will catch up, even with the current dry spell," he said.

While the New Ulm situation appears grim, McDevitt said the news is much worse for the stretch of Minnesota River from Mankato to Shakopee. McDevitt said the possibility of flooding on the Mississippi River also has worsened.

"We are now looking at moderate to major flooding on the Mississippi," McDevitt said. "We're looking at some pretty high water levels."

The towns of St. Paul, Hastings and Red Wing will be hit hardest by Mississippi flooding, McDevitt projects.

To read the graphics on possible flooding, visit the National Weather Service webpage at crh.noaa.gov/mpx