The Redwood River was running high near Wayside Rest, at the edge of Marshall, on Friday. A flood warning for the river will be in effect until Tuesday, but so far there have not been signs of flooding in the city of Marshall, Mayor Bob Byrnes said Friday.

MARSHALL — As rainstorms continued to soak southern Minnesota on Friday, flooding concerns rose in the region. On Friday afternoon, the National Weather Service issued a flood warning affecting the Redwood River in Lyon County, which will stay in effect until Tuesday. Flood warnings also included the Redwood River at Redwood Falls, the West Fork of the Des Moines River near Windom and Jackson, the Minnesota River at Montevideo and at Morton, and the Cottonwood River and Minnesota River in New Ulm.

Water levels on the Redwood at Marshall were forecast to reach a peak stage of around 15.5 feet on Saturday night, the NWS said. Flood stage in Marshall is 14 feet.

Although river levels were rising, there was not yet a flooding concern within the city of Marshall, Mayor Bob Byrnes said in a video address Friday afternoon.

“That is well within the protection area. We can go substantially higher than that before we would see any significant impact in the community,” Byrnes said. “At least for right now, we are watching, but we are not overly concerned with overflow from the river.”

A possible concern for Marshall would be if there was additional heavy rain Friday night or Saturday, Byrnes said. City staff were monitoring the situation, and watching to see if there was flooding in back yards or catch basins, he said.

Byrnes said one positive sign for Marshall was that, based on the flow at the city wastewater plant, it looked like residents are not running their sump pump hoses into the sanitary sewer.

Scott Przybilla, assistant wastewater superintendent in Marshall, said the wastewater plant saw a flow of about 3.3 million gallons of water on Thursday, which was average for a wet weather event. The plant’s design capacity is for 4.5 million gallons, he said.

So far in Marshall, “The ground isn’t quite as saturated as one would think it is,” Przybilla said. In addition, the city wastewater plant would able to store some excess water if flows increase.

On Friday afternoon, the U.S. Geological Survey reported the Redwood River near Marshall as being at a stage of 11.7 feet. River levels started rising on Monday, and spiked again after overnight rains Thursday, according to provisional data from the USGS.

Near Redwood Falls, the Redwood River was at a stage of 5.93 feet, compared to a flood stage of 6 feet.

USGS data also showed that the Minnesota River in Montevideo was at a stage of 13.52 feet, compared to a flood stage of 14 feet. By the time it reached Morton, the Minnesota River was at a stage of 22.43 feet, compared to a flood stage of 21 feet.

The highest recorded peak stage for the Redwood River near Marshall was 19.76 feet, on March 24, 2019, the USGS said. During the floods that hit Marshall in May 1993, the Redwood’s peak stage was 17 feet.

The past three months have been unusually wet for the Marshall area, said Tim Masters, a technician with the NWS office in Sioux Falls. Observed rainfall totals for June 1 up through Friday morning came to 4.75 inches, when the normal total for the entire month of June was about 4.1 inches, Masters said. Marshall also received 4.94 inches of rain in April, and 4.32 inches of rain in May, he said.

“We’re kind of stuck in a pattern between the heat and humidity to the south and east, while it’s still like late spring in our northwest,” Masters said.

NWS forecasts say the Marshall area should see some sun between Saturday and Sunday, but on Monday there are chances for showers and thunderstorms again.

Friday’s heavy rains led to flooding on highways in the region south of Lyon County. At different times during the day, the Minnesota Department of Transportation reported flooding or road closures on highways including U.S. Highway 75, U.S. Highway 59, Highway 91 and Interstate 90.

On Friday, the Minnesota Department of Health also urged people with private wells to prepare for the possibility that their wells might flood. Floodwater can contaminate drinking water and create a health risk.

In a news release, the MDH said that if floodwater has reached a private well, residents should assume the well is contaminated. The well water shouldn’t be used for drinking, cooking or brushing teeth until after floodwaters recede.

For people who have a private well that they think might become flooded, the MDH recommends storing a supply of clean water that will last at least a few days. The MDH also recommended shutting off power to the well pump, to keep floodwater from being pumped into plumbing systems or homes.

More information on flood precautions and disinfecting flooded wells is available on the MDH website, at https://www.health.state.mn.us/communities/environment/water/wells/natural.