Commuters traveling Monday between Indiana and Kentucky became mired for miles on end in unfamiliar travel patterns with few alternatives as the emergency closure of a bridge crossing the Ohio River left only two spans remaining, detouring tens of thousands.

"It was better than I anticipated, but I left really, really early," said Christy Grauel, of Corydon, Ind., the human resources director at Wyatt, Tarrant & Combs, a Louisville law firm. "That's leaving nearly an hour and a half sooner than I normally do."

Grauel said her usual 15-minute commute took 45 minutes, but other commuters said their normally short drives were up to two hours.

"I think everybody else had the same idea," said Randy Cissell, a video producer at the University of Louisville who said he left at 6:30 a.m. for what is normally a 20-minute ride, but didn't arrive until 8:30 a.m. EDT. He said his plan for Tuesday is to leave at 5:30 a.m., and had no idea what to expect for his evening commute back over the river.

Some commuters rode bikes, while still others left so early in the morning they planned to sleep in their vehicles until it was time to start their shifts.

In a move that stunned commuters on both sides of the river, officials abruptly closed the 50-year-old Sherman Minton Bridge on Friday when inspectors found cracks in the bridge's steel. The Interstate 64 bridge connects the western side of Louisville with New Albany, Ind., handling 80,000 vehicles a day, most of them commuters, officials said.

The closure left just two other southern Indiana-Kentucky bridges to handle the detoured traffic. Officials in both states worked through the weekend on plans to re-route traffic and highway construction work on the Kentucky side was suspended.

"You just got to wonder if the other bridges can withstand this extra load," Cissell said.

Officials warned that local traffic in both states would also likely be heavy, even for those who do not need to cross the spans.

"It is critical that commuters ... both morning and afternoon, realize that familiar driving habits simply will not work for the vast majority of people," Ryan Gallagher, director of traffic management for the Indiana Department of Transportation, said in a news release.

Employers throughout Louisville were faced with the challenge of how to best deal with a situation not likely to change anytime soon. Officials said it will take three weeks simply to diagnose the problems, and a closure of six months or more is possible.

Jim Turner, spokesman for insurer Humana Inc., headquartered in Louisville, said the company will consider as the week goes on whether it is necessary to adjust schedules, make work-at-home arrangements and change operating hours.

Grauel said she helped contact the roughly 25 employees of her law firm that live in Indiana on Sunday, telling them to come in early or late, but try to avoid driving into Louisville between 7 a.m. and 9 a.m. EDT. The firm also installed several new computers at its New Albany, Ind., offices and is allowing some people to work there, she said.

Officials at the firm plan to meet Monday to discuss long-term options for employees, with the prospect of the bridge being closed for several months, Grauel said.

"We're going to try and get around the table and figure it out," she said.

The provost at the University of Louisville sent a memo to faculty, staff and students Sunday, urging them to "be understanding" if students and employees are "a little late for the next few days."

"Repairing the bridge will be a long-term issue, not a quick fix," Shirley C. Willihnganz said in the memo. "With planning, a little patience and some teamwork we can ensure its impact on our classes and operations will not be too harsh."

University spokesman Mark Hebert said Monday that school officials were working on finding out how many employees and students travel from southern Indiana to the downtown campus of the state's second-largest public research university.

"There's already a policy allowing flex scheduling and working from home with supervisory approval, though some folks obviously can't do their jobs from home," Hebert said.

The bridge closure came just one day after President Barack Obama urged Congress in a nationally televised speech to pass his jobs bill, which includes funding for infrastructure projects. However, the bridge Obama specifically cited in the speech as in dire need of repair was the crumbling Brent Spence Bridge that spans the Ohio River connecting Kentucky to southern Ohio.

Kentucky and Indiana officials have for years discussed plans to build two new bridges linking southern Indiana and the Louisville area. Officials are wrangling over how best to fund what is known as the Ohio River Bridges Project, which is expected to cost at least $2.9 billion and includes building two new bridges while redesigning a busy downtown interchange.

The project is also fighting a court challenge by an environmental group.