Flood preparations in Stillwater, April 13, 2023 (Greg Seitz/St. Croix 360)

A sudden spell of hot weather has quickly melted a lot of snow in the past week, and the water has rushed into the St. Croix River. As predicted for weeks, the river is now flooding. The latest forecast from the National Weather Service says it could hit 689 feet above sea level, the cutoff for what’s consider “major” flood stage.

The intense runoff this week has already triggered flood warnings along the upper St. Croix and its tributaries, and that water is now heading downstream. As of this writing, the water is flowing at 40,000 cubic feet per second at St. Croix Falls — some 18 million gallons per minute — and still rising.

In Stillwater, the water has risen more than six feet in the past six days. A temporary dike has been completed and the water is beginning to lap at its base in places. The images below show estimates of where flood waters could spread if they reach certain elevations — if no dike was built.

Flood advisories and warnings were issued yesterday for the upper St. Croix and other rivers around the region by the National Weather Service’s Duluth office. Rain predicted for this weekend has heightened the risk. Local counties have declared emergencies as they were forced to close several roads because of flooding. Most roads appear to be already reopening.

The river at Danbury is cresting currently after rising five feet in the past week, leveling off in what the National Weather Service considers “minor” flood stage. Water is expected to affect some low-lying areas, and will be less than a foot away from beginning to affect Highway 35 north of Riverside Landing. A flood warning is expected to expire Monday at 4 p.m.

Minor flooding has been reported along the upper Kettle River, which has risen about eight feet in the past few days, in Barnum and Moose Lake.

Along another St. Croix tributary, the Snake, the water has come up about three feet, and is expected to rise another two. At that level, water may begin encroaching some of the lowest-lying homes along the river and its lakes.

Today, the National Weather Service issued a warning for the Snake River, saying imminent precipitation could make matters worse.

“Rain on top of the existing snowpack will increase the rate of snowmelt,” the agency’s meteorologists wrote. “The resultant runoff will cause water levels in area rivers to increase and flooding is expected.”

The warning is in effect starting Sunday. The forecast calls for a crest of nine feet, just two-and-a-half inches below its apex in late April 2001. It is expected to fall back below flood stage a few hours later.

In response to the high water, the National Park Service and the Minnesota Department of Natural Resources have announced several closures and restrictions.

Last night, the DNR declared the river at Stillwater had reached 683 feet above sea level, the trigger for no wake rules on the entire lower river from Taylors Falls to Prescott. Signs will be posted at landings and boaters must maintain the slowest possible speed to maintain steerage, but no greater than five mph. Failure to comply can result in a citation.

The National Park Service has also closed all its landings and access points along the entire St. Croix National Scenic Riverway, including the Namekagon River and the St. Croix down to the Boom Site. The agency says conditions are “very high, fast flowing, and cold with significant amounts of floating debris.”

“Our priority is keeping visitors safe. Everyone should use extreme caution during these high-water conditions and stay out of closed areas,” stated Craig Hansen, superintendent of the St. Croix National Scenic Riverway.

The National Weather Service has simple advice for surviving floods: “Turn around, don`t drown when encountering flooded roads. Most flood deaths occur in vehicles.”

Stay safe out there. This is the river’s time.