Sioux Falls paves the way for major traffic projects

Two high trafficked areas of Sioux Falls will soon start to get some major changes in the coming years. Crews will begin "raising the road" above the railroad tracks at 26th and Southeastern starting in 2019. Even though the 85th street and I-29 interchange project recently passed a new milestone, drivers will have to wait a few years before that's a reality.

“It’s a key gateway interchange into our community, but it really is going to support the growth and development of Sioux Falls and the city of Tea,” Sioux Falls Public Works Department Director Mark Cotter said

Construction on a first of its kind interchange in Sioux Falls could be a reality in a just a few years.

“You can either get off at the Tea exit or you can get off at 41st street and there’s nowhere in-between to get off besides taking the 229 exit,” Cotter said.

The newly constructed “Diverging Diamond Interchange” also known as a DDI at 85th and I-29 will have typical features like on and off ramps. But…

“You actually cross the traffic over as people enter the interchange and then you cross them back over as they leave,” Cotter said.

That will give those drivers a little more 'peace of mind' behind the wheel.

“When you look at a traditional interchange, there’s about 26 points where people can come into conflict. In a DDI there’s about 14,” Cotter said. “So they're much safer, higher volume, which ultimately means less delay for driver.”

Drivers on the east side, passing 26th and Southeastern, feel that struggle.

“As you drive out there today, you'll see that the railroad and the road are at the same grade,” Cotter said. “We’re going to separate those two.”

Signs are up so drivers know crews will soon begin work to "raise the road” by 30 feet over the railroad tracks.

“If we can separate train traffic and vehicle traffic, that makes it much safer,” Cotter said.

In fact, the new road will be elevated to the same height as the traffic lights.

“Which will allow us to have the roadway surface high enough to go over the railroad track and then ultimately this will require us to reconstruct the bridge over the Big Sioux River,” Cotter said. “So no longer will there be a train delay and that’s a huge win.”

Cotter said the DDI interchange and work on the I-29 and I-229 pieces will cost about $25 million. The cost to raise the road on the east side will cost about $41 million between the city and the DOT.

The “Diverging Diamond Interchange” is also the leading design for the 41 street, I-29 intersection.