Don't start filling sandbags yet: Too early to tell if spring floods will come
In the past two weeks, Goodhue County has received nearly 11 inches of snow and nearly three-quarters of an inch of rain. All that moisture might eventually make its way to the Mississippi, causing the river to overrun its banks and Goodhue County residents to start piling up the sandbags.
Or, it might not.
Long story short, the jury is still out on whether all the recent precipitation will result in any significant spring flooding.
"It's too early to tell," said Ryan Sterry, agriculture educator with St. Croix County University of Wisconsin Extension Office. "It's tough to say one way or another."
It all depends on how much it rains this spring, how quickly temperatures rise and when the ground thaws, Sterry said.
Currently, frost has infiltrated the soil as much as three to four feet down. When the snow does start to melt, that frost layer could mean that the water won't absorb into the soil, but will run off into rivers and creeks instead, causing flooding, Sterry said.
Last year, spring flooding was minimal because early warm temps allowed the ground to thaw quickly. Snow melt was then absorbed into the soil, rather than just running off.
"We're going to need a lot of sun and a lot of warm days this year for the same thing to happen," Sterry said. "We were awfully dry going into the fall. The ground can take a lot of water right now; it's just matter of getting the frost out so it can do that."
Whether that happens all depends on what kind of weather the next couple of weeks bring, Sterry said.
Still, despite the uncertainty, the Minnesota Commerce Department issued a statement last week encouraging homeowners to purchase flood insurance, adding that normal insurance policies do not cover flood damage.
"Homeowners should closely monitor spring flood forecasts as Minnesota emerges from last fall's moderate to severe drought, to protect themselves from flooding's potential dangers and risks of property damage," Commerce Commissioner Mike Rothman said.
Flood stage in Red Wing is 14 feet, but river levels aren't being measured here yet.
The city of Red Wing's flood preparations haven't gotten under way either, Deputy Director of Public Services Lynn Nardinger said. But city crews are keeping a close watch on water levels.
"We're monitoring what the forecasts are," Nardinger said. "We're monitoring how much snow we've gotten."
Nardinger said river levels in Red Wing did rise slightly after last week's rain showers.
"It's gone up a little bit. But very little so far," he said.
One thing that might help prevent spring flooding is a very dry fall. Nardinger said measurements taken before the snow fell showed rivers levels to be especially low.
"Rivers were probably the lowest readings we've seen for a number of years," he said. "I think a lot of the catch basins, ponds need to fill up before a lot of that is even going to reach the river."
But Nardinger said there are other factors that could cause flooding, including spring rains and ice jams - which form when temperatures rise quickly and river ice doesn't have a chance to melt before it gets dislodged and floats downstream, creating a dam.
Still, this early in the game, Nardinger said it's basically just wait and see.
"We'll just keep an eye on what the river levels are in the next few weeks," he said.