In a first for the state, deer and other critters can now amble along a 200-foot-long man-made tunnel carved into the earth under a southern Minnesota highway.

Why? To get to the other side, of course — without the risk of becoming roadkill.

The newly opened north-south passageway designed specifically with deer in mind runs beneath Hwy. 14, measures 10 feet tall and 9 feet wide, and is located between Owatonna and Dodge Center.

The Minnesota departments of Transportation (MnDOT) and Natural Resources (DNR) collaborated on the design and determined the best spot for optimal use, with deer anticipated to be the most likely form of wildlife to be attracted to the box-shaped tube, followed by the occasional raccoon, possum or turtle.

Placement was based on reports of deer movement from observers dispatched into the field.

Jeanine Vorland, a DNR wildlife manager in that part of the state, observed that deer roam all around the area of the Dodge Center Creek watershed in the spring and summer. But come winter, the deer have a habit of heading south and over Hwy. 14 at great peril of being run over.

"It is my understanding wildlife-vehicle encounters are a leading cause of accidents along this stretch of Highway 14," said Vorland, "and one should not discount the near misses and collisions with smaller animals such as raccoons either."

Of course, just because you build it doesn't mean they'll come with the flip of a switch.

"We have no illusion in all the deer in this area using this structure," said MnDOT wildlife ecologist Christopher Smith. "We placed the culvert in an area we knew had high deer movement, [and] there are things we can do in the future, adding shrubs and trees to funnel the deer to the structure, and fencing to physically direct them to the culvert."

But for all the man-made schemes devised to coax the deer in one way and out the other, Smith said, nature is also being counted on to do its part.

"They do learn and show their offspring where the safe places are," he said. "Over time, we will see an increased use. ... It won't be in an instant. They are creatures that learn the safe places to hang out."

Determining the culvert's ultimate length was no accident. After all, what living creature wants to enter a narrow, dark space for the first time without a hint of getting out on the other end?

"It's designed to be short enough to show daylight through it," Smith said, "which helps encourage use."

The concrete culvert is just a sliver of the larger Hwy. 14 project underway to expand 12 ½ miles of road from two to four lanes. Cost for the culvert was $219,000, out of the $108 million pegged for the overall project.

MnDOT frequently revisits bridges and culverts statewide to see if modifications can be made to potentially help wildlife avoid highway traffic, but this is the first structure designed from the start primarily as a deer crossing.

One after-construction adjustment was made several years ago to a Hwy. 14 bridge over Dodge Center Creek that made it more inviting for deer and other animals to migrate.

Paul Walsh • 612-673-4482