This map shows the Gilmore Creek levee system and the area protected by it. The bold line in the southwest represents the levee. The shaded area represents areas that would be flooded in a 100-year flood if they were not protected by the levee system.
This map shows the Mississippi River levee system and the area protected by it.
The bold line represents the levee. The dots along that line represent pumping stations. The shaded areas would be flooded in a 1,000-year flood if they were not protected by the levee system.
by CHRIS ROGERS
Without the levee system, most of Winona would be underwater in a major flood. Without a Federal Emergency Management Agency (FEMA) accredited levee, most of Winona would be in the floodplain, meaning that many homeowners and businesses would have to pay significantly more for insurance.
For the last several years, the city of Winona and the U.S. Army Corps of Engineers (USACE) have been working on getting Winona’s levee up to code and getting it re-accredited by FEMA so that the city stays dry during actual floods and so that property owners do not have to pay thousands more for flood insurance. It has taken longer than expected and, after the city and the USACE ran into problems, they are pursuing a different approach to try to get FEMA’s endorsement for the levees.
Earlier this fall, Winona Public Works Director Keith Nelson assured residents that while the city has run into problems getting the levee accredited, the levee system is in good condition and not in danger of failing. In a subsequent interview, USACE Levee Safety Program Manager Eric Wittine clarified that Winonans should know that no levee system is perfectly safe. “They live behind a levee system and [should] understand, even though it’s remote, there’s the potential for something to happen,” Wittine stated. That said, he added, “By all means, we expect the levee to perform as designed in the next event. There’s no imminent failure.”
There are two levee systems in Winona. A small levee system around Gilmore Creek and Boller’s Lake protects part of Winona from Gilmore Creek flooding. (See map 1.) This fall, Nelson announced that it would be virtually impossible for the city to get that levee system re-accredited. It is not going to happen, he told the City Council. Unless that changes, some homes around Gilmore Creek and Lake Winona will likely be added to the floodplain as a result and may need to buy expensive flood insurance.
The second, far larger levee system protects the city of Winona from the Mississippi River. (See map 2.) City and the USACE officials are working to get that levee re-accredited, and they are hopeful their efforts will be successful. The city just entered a contract to split the $500,000 cost of that work — a study called a high-level risk assessment — with the USACE. It is unclear how long the risk assessment will take the USACE to complete. Wittine said it is typically a six-month process, but one rough timeline in the USACE’s contract with the city indicates it could take over a year. That study may identify on-the-ground projects, repairs, or fortifications that are needed, which would take more time and money.
“We’re bringing in a huge number of experts to look at this system, because it exceeds our expertise here,” USACE Public Affairs Officer Shannon Bauer said. USACE experts from across the country will help review Winona’s levee system. “They basically go through every single failure mode that could occur with the levee,” Wittine explained. “The net outcome of the risk assessment is an illuminated path forward,” he added. “Basically, we’re looking at, what kind of repairs need to be done to get the biggest bang for the buck?” Bauer stated.
Keep reading the Winona Post for more on this story.
Illustration by Monica Veraguth, based on FEMA maps