On the morning of March 15, a mix of snow and freezing precipitation turned Interstate 94 between Alexandria and Moorhead, Minn., to ice. Scores of vehicles landed in the ditch and at least three semitrailer trucks jackknifed. Authorities closed the 100-mile stretch of freeway for several hours.

Last Monday, they shut down the same freeway again when a wind-whipped snowstorm created low visibility and dangerous driving conditions that factored into numerous multivehicle crashes and rollovers by big rigs.

But I-94 was not closed on the evening of March 15 when conditions turned treacherous and authorities and tow truck drivers could not keep up with calls from motorists who had slid off the road.

The decision to close a freeway or major highway is not made lightly, said Capt. Bruce Hentges of the Minnesota State Patrol. It's a balancing act between keeping vital links between cities open and keeping the public safe. In making the call to close a road or not, the patrol and MnDOT officials gather information from law enforcement officers and MnDOT plow drivers. They also keep conditions, wind, weather forecasts and even the day and time in mind.

"Closing the road too early causes unnecessary delays to the public and hurts our credibility as an agency," said Jeff Perkins, operations manager for MnDOT's west central Minnesota district. "Closing the road too late has the potential to significantly delay when we are able to reopen the roadway."

Shutting down a road is not a simple process, either. It takes one to two hours to notify other agencies (local police, county sheriff's offices), activate message boards to alert motorists and deploy crews to lower gates and place barricades at entrance points. Troopers also drive the segment to look for stranded motorists.

Low visibility is the most common reason for road closing, Hentges said. But if MnDOT cannot keep the roadway clear, that also can lead to a closure.

"If it's not passable and someone could get stuck in a corridor and we can't get to them, then we close the roadway down," said Mark Fischbach, a MnDOT freeway superintendent. "We don't plan on closing roads, but we are prepared to."

Not closing a freeway can lead to even longer delays. All trucks and vehicles blocking lanes must be cleared before a road can be reopened. That can take several hours, sometimes longer than a road closure. I-94 has been closed for four to five hours three times this winter due to crashes or semitrailer trucks that have rolled over or jackknifed, Hentges said.

Sgt. Jesse Grabow of the State Patrol said several motorists have been stopped for driving on closed roads this year.

The most common excuse given by lawbreakers, he said, is that they "needed to get home from work, but not one emergency." Drivers can be fined up to $1,000 and sentenced to 90 days in jail for traveling on a closed road.

When possible, detours will be set up, but in rural areas, that can be difficult because the next exit might be 20 miles away, Hentges said.

Even when roads are open, it doesn't mean they are always safe. Hentges said troopers routinely see drivers who are oblivious to road conditions.

"It is not unusual to clock vehicles moving at 70 miles per hour on roads affected by ice and snow."

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