Inside the new interchange coming to I-29 and 41st Street
A crowd of people milled around the former PacSun inside the Empire Mall to learn about the new interchange at I-29 and 41st Street that will begin construction in April.
During the open house, people had the chance to watch animations of the diverging diamond interchange, learn about the construction timeline and try their hand at walking the diamond.
Here's what you need to know about how the second diverging diamond in the state, and the first for Sioux Falls, will impact western Sioux Falls.
What is a diverging diamond?
The idea of the interchange is that it'll create safer left-turns and in turn create a safer driving environment at what has been called the most dangerous intersection in Sioux Falls.
The intersection at 41st Street and I-29 had more crashes than any other site in the city between 2016-2018, according to previous reporting by the Argus.
More: 'It's just a mess': Fixing the most dangerous intersection in Sioux Falls
The diverging diamond interchange will be the city's first and could reduce the amount of crashes by over 60%, said Shannon Ausen, a civil engineer with the city. There will be an added lane of traffic with a raised median, which will include a pedestrian walkway.
"When you have so many lanes and so many turning movements, you need a little more control," Ausen said at the open house.
More: Reconstruction of Sioux Falls' most dangerous intersection begins next year
Ausen explained that in an intersection like the one at 41st Street, which has a lot of left turns, by having the diamond take someone from the right lane straight into the left lane with a traffic signal, they will be able to make an easier left turn.
Wait, I'll switch to the other side of the road?
In a sense, yes.
Say you're coming from the east on 41st Street and you want go south on I-29, you'll stop a traffic light while in the inside lane. When the arrow goes green, you'll switch over to the west side of the while you drive in the inside lane and then take a left onto I-29. If you want to keep going east on 41st Street, you'll stop at a second set of traffic lights before switching back to the east.
The video below takes you through it.
There will be retaining walls on either side of the road, making it difficult to crash through to the other side.
When is construction set to start?
The project is expected to start in April and last through 2024.
Between Marion Road and Meadow Avenue along the west side 41st Street will be under construction from April to November. During that time there will be road closures and one lane of traffic will be open along 41st Street. A more detailed list is below.
April 2022: South side of 41st Street along Meadow Avenue to west of Marion Road. No road closures expected.
June 2022: Marion Road south of 41st Street will be closed for approximately one month. Use Sertoma Avenue and 57th Street as a detour.
July 2022: North side of 41st Street along Meadow Avenue to west of Marion Road. No road closures expected.
September 2022: Marion Road will be closed north of 41st Street for approximately a month. Use Sertoma Avenue and 26th Street as a detour.
While Marion Road is closed, business access will be along Larch Avenue and 44th Street.
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The diverging diamond and construction along the east side of 41st Street is expected begin in 2023 and include Meadow Avenue to Shirley Avenue. Construction is expected to begin in April 2023 and finish around November 2023.
Can I still access I-29?
Yep. Throughout the project, there will be east and westbound access along 41st Street to I-29.
Ausen said to expect it "to be slow-moving" at times because of the one lane of traffic.
How will this impact my commute?
Ausen said that the first few weeks will be a little difficult as people learn how the construction is impacting their drive times.
"By the second week, everybody is gone because they've found another route but then by the third, forth or fifth week, people are starting to come back because they've realized it's not too bad," she said. "It's going to be a long two years though."
Where can I learn more and watch videos?
You can visit the city's project website to watch animations and learn more about the project timeline.
Follow Annie Todd on Twitter @AnnieTodd96. Reach out to her with tips, questions and other community news at atodd@argusleader.com or give her a call at 605-215-3757.
This article originally appeared on Sioux Falls Argus Leader: How will diverging diamond interchange at 41st Street and I-29 work
