Have you ever wondered: Why aren't there any exits south of 41st Street on I-29?

SIOUX FALLS, S.D. - All three interstates in Sioux Falls were built around the same time in 1961. Since then, Interstate 29 in Sioux Falls has been completely reconstructed. It was a different time in the 1960s when I-29 was first built.

Travis Dressen is an engineer for the South Dakota Department of Transportation, and he said there were only four exits and two lanes in each direction at that time.

"The west city limit line for Sioux Falls was about a half a mile east of the interstate," Dressen said. "Then, the south city limit was right at 57th Street, which is the Minnehaha-Lincoln county line. Beyond that, there wasn't any development at the time."

Roads have since been upgraded to sustain the current traffic volume including more lanes and exits. In order to make these changes, the Department of Transportation has to look at how these changes will improve the overall system. Sometimes that includes a study. In 2000, researchers looked at putting an interchange at 49th Street.

"It was determined to be infeasible. Federal Highway Administration requires one mile spacing between interchanges. 49th Street lies a half a mile south of 41st Street, so it doesn't meet that spacing requirement for interchanges," Dressen said.

Another study was done in 2010 to look at adding an interchange at 57th Street.

"With the proximity of the Good Samaritan Center and some of the other businesses around that interchange, it would be cost infeasible to construct an interchange at 57th Street," Dressen said.

Instead, improvements will be made to the 41st Street interchange in 2023, adding more lanes on 41st Street right off the interstate.

An overpass at 85th Street is expected to be added in 2020 and one at 69th Street after the year 2025. Until those changes, drivers will have to either get off at 41st Street or drive to the Tea Exit and work their way back.

The South Dakota Department of Transportation's website has a list of studies you can look at, which we've linked in the related links section of this article. If you have a question you'd like answered, reach out to Vanessa Gomez. Her email is vgomez@ksfy.com.