Residents and travelers along the major rivers that converge on the Twin Cities metro area shouldn’t notice any significant flooding this spring, according to an update issued Friday by the North Central River Forecast Center (NCRFC).
Chances of the Mississippi River at St. Paul rising to the level it did two years ago, when it closed Warner and Shepard Roads near downtown, are less than 10 percent. The Minnesota River has similar low chances of overtaking roads and bridges in the southwest metro; it’s been assigned a 5 percent chance of affecting Interstate 35W between Burnsville and Bloomington. Chances that the St. Croix would limit operations of the Stillwater Lift Bridge are less than 20 percent, the center said.
The outlook, effective through June 30, comes a week after hydrologists posted high probabilities of significant flooding along the Red River of the North, which forms the border between Minnesota and North Dakota. Fargo faces a 50 percent chance of a river level that would be among the five highest on record, but a less than 2 percent chance of matching the record it saw in 2009. That outlook was not updated Friday.
Fargo’s volunteer sandbagging effort is scheduled to begin Wednesday. North Dakota Gov. Jack Dalrymple signed a declaration Friday committing state agencies to prepare for flood emergencies along the Red.
Friday’s update for southern and central Minnesota takes into account the late winter snow across the region, which still is 18 inches to 2 feet deep around the headwaters of the Mississippi and Minnesota rivers and contains 4 to 6 inches of water. The update also considers the range of actual spring rainfalls through history.
Much of the meltwater from heavy snow along the upper reaches of the Mississippi should be absorbed by wetlands and lakes that shrank during drought conditions in late summer and fall, said NCRFC hydrologist Diane Cooper.
At Aitkin, there is a less than 20 percent chance the city’s wastewater treatment operations might be affected, and a less than 5 percent chance that Hwy. 169 would be affected.
At Montevideo, along the Minnesota River, the outlook cites a less than 10 percent chance that some low-lying homes and businesses could see flooding. The city, which was slammed by floodwaters in 1997, in recent years has built new levees, reinforced another and removed all but eight of 130 homes from a flood-prone neighborhood. It’s even selling part of its supply of sandbags to other cities, said City Manager Steve Jones.
On the upper reaches of the Mississippi and Minnesota rivers, ice remains up to 2 feet thick, increasing the potential for ice jams if warm weather breaks the rivers open suddenly, Cooper noted. Ice jams can cause floods that can’t be predicted.
Despite the deep snows still on the ground, experts do not expect the spring thaw to provide much relief for dry soil below. Deep cold in the soil is expected to prevent most meltwater from soaking in, particularly if the thaw comes on suddenly. That’s increasingly likely with the arrival of April.