No washing away worries
WORTHINGTON -- Sunday's snow showers, and the likelihood of more snow in the region in the next few days, is certainly not good news for the state's flood forecasters.
Even before the snow fell Sunday morning, the region was looking at an 80 percent chance of minor flooding, a 60 to 80 percent chance of moderate flooding and a 20 percent chance of major flooding, according to Tom Kresko, area hydrologist with the Department of Natural Resources in Windom.
Adding to the worries of potential flooding this spring is that the month of March, in a La Ninã weather pattern, is expected to be wetter than normal.
"Right now, this month's forecast is not looking very good," said Kresko. "We don't need that additional moisture."
Most people may remember the concern for flooding in the region last year at this time. A year ago, Kresko reported in a Daily Globe article that there were between 19.5 and 21 inches of snow on the ground, with the water equivalency range from 6 to 8 inches.
In mid-February, Kresko measured the snow depth in Worthington at nearly 16 inches, with a water equivalency of about 5 inches.
"Obviously, we've had a couple of storms since then and a little bit of melting since then as well," he said on Friday. "I bet we're probably still in that category -- maybe a little bit more."
At the same time, there was talk of a significant snow event coming into the region this week.
"Last March, we didn't have a flake of snowfall, thank goodness," Kresko said.
There was also a gradual warm-up last spring, with days of melting followed by nights of freezing. If that can happen again this year, Kresko said it will help.
"The later we get into March, the more likely we are to get a quicker melt," he said. "We didn't get a January thaw like which is common, but that February melt was a significant factor in getting some of that water downstream."
The best hope now is to get some of those western winds blowing in out of the Rockies, Kresko said, adding they are much drier and can help to evaporate up to a quarter to a third of an inch of water per day.
While Kresko hasn't been back to Worthington to take measurements since Feb. 11, he said the community has a high risk of flooding.
"There's a large portion of the city that is in the flood plain," he said. If people saw water in their basement last spring -- or even in September when the region received 5 to 10 inches of rain -- there's a good chance they will be dealing with the same issues within the next month or so.
"If (people) don't already have flood insurance, I would encourage them to look into it," said Kresko. "Unfortunately, there is a 30-day waiting period, but if things stay cold, it could easily be into April before we reach peak flooding scenarios."
He also encourages people to check now to ensure their sump pump and hoses are sufficient, and said a back-up pump and second hose are a worthwhile investment.
To alleviate some of the water that may seep into a home, Kresko said homeowners should create pathways through the snow for the water to get away from the foundation.
In the rural areas, feedlot operators should protect their feedstuffs from potential runoff, added Nobles County Feedlot Officer Alan Langseth.
"If (flooding is) imminent, move your livestock to higher ground," Langseth said. "Be aware that it could potentially lead to environmental concerns if manure storage facilities are flooded."
Kresko also encourages rural residents to keep an eye out for overtopped roadways and washed-out culverts, and notify township or county officials of roads that are flooded.
"Most of those areas ... that had impact from the rain event at the end of September are likely to have similar flooding this spring," Kresko said. "I would expect the water levels to be at least as high as that, if not higher in some areas. I think this spring flood event has the potential to be more significant."
Kresko said moderate flooding is a "very likely" situation, with the Des Moines River already pegged at a greater than 98 percent chance of minor flooding, a 95 percent probability of moderate flooding and a 35 percent chance of major flooding. The river flows through both Windom and Jackson.
"What we saw last fall and even last spring was a pretty moderate event," said Kresko. "The likelihood of us going a step higher and getting close to, or even having major flooding, is something we're going to have to face."
Kresko said the region can handle moderate flooding, but even with that there is a concern.
"We had a number of culverts and bridges that got replaced or rip-rapped last fall, but there were also a lot of them that needed to get done and didn't get done," he said. "They are weakened, and that concerns me."