The bridge is the only connection across the Mississippi River for many miles around, and that means thousands of residents in Minnesota and Wisconsin are facing commute times that have doubled, tripled and worse.
Local employers are scrambling to find resources to help connect employees to carpools and busses. There's even talk of a ferry service.
MnDOT officials closed the bridge earlier this week after inspectors found several corroded gusset plates.
The sudden action left cross-river commuters like Winona State University student Sara McCay scrambling to find another way to get to school.
"I was at the bar last night running around asking people, 'Do you commute to Winona? Do you commute to Winona?' It really is an interesting thing," McCay said.
McCay, who lives in nearby Fountain City, Wis., didn't want to have to drive her car on the much longer detour route to school. But she wound up driving her 1989 Geo Prism, with no muffler, 30 miles south down to LaCrosse. Then she took the I-90 bridge across to LaCrescent, Minn. and drove 30 miles north back up to Winona.
McCay's normally 12-minute commute took an hour and a half.
"I have to consider all the wear and tear on my car. And the gas that has to be considered part of my tuition. So, my tuition has just gone up," she concluded.
Winona State University officials estimate that there are more than 500 other students attending summer classes who, like Sara McCay, commute from Wisconsin.
When they heard about the bridge closing, university officials say the school immediately sent e-mails out to students to offer help.
The school has offered to help pair up commuting students to share rides. They are also considering using on-campus housing for students who may have to stay in Winona on the days they have classes.
Winona State employs about 900 faculty and staff. Nearly 200 of them commute from Wisconsin. Some have already started carpooling together.
Winona State President Judith Ramaley says the bridge closing may lead to longer term changes to the workplace.
"We may try to create within our own work environment, different patterns of work, flexible work hours," Ramaly said. "Maybe packaging things so that people don't have to come here every day, but perhaps have a couple longer days, and don't have to commute."
Other Winona employers are having similar conversations with their Wisconsin commuters. A number of the city's manufacturing companies report they are working to get employees to ride share.
They're also hoping the city or the Chamber of Commerce might help coordinate carpooling, so employees from different companies who live near one another could ride together.
Winona City Manager Eric Sorenson recently met with local business owners. He says many of them voiced frustration about the bridge closing. The bridge not only helps their employees get to and from work, but it also brings customers.
Sorenson says some businesses are exploring a series of options for their Wisconsin employees - from establishing a ferry system to cross the river, to putting them up in hotels on nights where the commute would be too difficult.
"The way we're going to find a solution is the way we found a solution last year [during the flood]," Sorenson said. "It was encouraging, what we saw -- with all the flood devastation -- people came together. That's how it happened."
The flood waters that covered the city last fall have long since receded. But if MnDOT determines the bridge needs to be immediately replaced, Winona residents will find themselves with a much longer lasting crisis.
MnDOT will have a better idea of what kind of treatment the bridge will need by the end of this week.