Where's the logic of construction season?

Driving west on Interstate 94, Alex Philstrom, Twin Cities resident of 12 years, observes the situation on the eastbound side of the highway where the Minnesota Department of Transportation had barricaded a big section of the main artery between Minneapolis and St Paul.

"It just looks like orange. Everywhere. All over all the streets. Orange," Philstrom said.

As Philstrom approaches the Lyndale/Hennepin exit, a traffic jam starts to form on the other side of I-94.

"And it's just now really coming to a standstill," she said.

On the north side of the of I-94 tunnel, traffic is backed up all the way to I-394.

The Minnesota Department of Transportation planned that closure of eastbound 94 years ago.

Closing a freeway was once a radical thought, said MnDOT engineer Tiffany Dagon.

"The thought was 'You can't shut that down; you have to keep traffic moving, the public won't accept it,'" Dagon said. "We found out that's not true."

The first time Dagon and MnDOT Director Tom O'Keefe can remember closing a major road was Highway 36 in 2007. Dagon says MnDOT chose to shut the road entirely for five months instead of blocking off a few lanes for two years.

"Before the project there was market research done and it was pretty, pretty split 50-50 on full closure versus two-year construction and keeping the road open," Dagon said. "And after the construction was done, they did research again and found that 90 percent of the respondents were happy with the closure and preferred that to the two-year option."

Dagon said drivers respond well when they learn full closures are cheaper, because construction crews don't have to spend time every day setting equipment up and getting it back in place.

But closures do lead to detours. MnDOT tries to route detoured traffic to other state roads. When they send traffic to county or city roads the state must compensate those entities. Consequently, O'Keefe said the recommended detour is often the quickest route for people on long-distance trips, but not for people going short distances.

That's why and how roads are closed — but why do it so often? O'Keefe said there are more road projects now than ever before.

"Much of our interstate freeways which carry the greatest volume of our traffic in Minnesota in the metro area were built in the '60s and '70s," O'Keefe said. "They're coming due for replacement now."

There are those who ask if all of this is necessary. David Levinson, a civil engineering professor at the University of Minnesota who has worked with MnDOT, points out that once a road is closed it is cheaper to perform as many repairs as possible. On the I-94 project, MnDOT did not just increase capacity, it used the opportunity to upgrade the drainage system even though it might not have been at the point where it was absolutely needed.

"The question is: are our standards too high," Levinson said. "We demand that lanes be certain widths and we demand that pavements be certain thicknesses and drainage be certain ways — which are really all nice things to have, but are also costly.

"And the cost is not just the money spent but the delay and people who suffer through the construction process."

But road improvements have to be done sooner or later, says Dagon. She hopes people trust the decisions she and her colleagues make.

"I guess one thing I'd want people to know is we work really hard to meet people's needs."

The next large project is to replace bridges and an interchange on I-35E north of downtown St Paul. Dagon's group at MnDOT decided against closing the section because they found the displaced traffic would put too much of a burden on other roads. Instead, beginning in 2014, traffic will squeeze through a construction zone.

The work will take about two years and the improvements will last about 35 years, Dagon said.

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