Sep 23, 2021 12:00 PM

MoDOT Northwest zeroes in on three I-229 double-decker bridge alternative ideas

Posted Sep 23, 2021 12:00 PM
Photo by Brent Martin.
Photo by Brent Martin.


St. Joseph Post

The Missouri Department of Transportation has talked about alternatives to the I-229 double-decker bridge in St. Joseph for years now.

Those talks have gained momentum over the last three years, and have really been progressing in 2021.

Marty Liles, the district engineer for MoDOT Northwest, says these discussions have ramped up in recent years as the double-decker bridge continues to age and more maintenance is needed.

"The double-decker bridge is really getting to that point where it's going to need some repairs and some major ones," Liles said. "So, why we did an environmental study is to really start looking at what is the best solution for that double-decker in the future?"

MoDOT has been conducting an environmental study for the last year-and-a-half, looking at reasonable alternatives to the bridge, talking with the public and consulting with state and local officials on how to best move forward.

MoDOT held a public meeting at the Remington Nature Center last year to get input from the general public on what alternatives to the double-decker bridge would look like.

What started as 20 alternative ideas has been narrowed down to three. Those top three alternatives have taken various ideas from other proposals.

All three ideas would have the double-decker bridge removed. One proposal would put a two or four-lane road at grade in the same location as the bridge - between the railroad tracks and the Missouri River.

Option 1.
Option 1.

A second option would have a four-lane arterial constructed at grade in the same location as the bridge, with the exception of a section between Messanie Street and Francis Street. This would also include the addition of a traffic signal at the intersection of 2nd and Felix rather than a roundabout.

Option 2.
Option 2.

The third option would have a scenic, at-grade, four-lane parkway built from McArthur Drive on the north end to a new bridge that connects to Duncan Street on the south end. The parkway would be in the same location as the existing double-decker bridge.

Option 3.
Option 3.

The option of keeping and maintaining the current bridge, Liles said, is still on the table. But, its upkeep would be costly and time consuming.

"In order to rehab that bridge, it's going to take a considerable amount of money," Liles said. "Eventually, this thing is going to have to have some major repairs done to it, and that's just to carry it along for another 20-25 years. But, you're looking at pry anywhere from $50-60 million just to carry this along."

Liles says that harsh Missouri winters, along with added moisture from being close to the river, doesn't help the situation with the double-decker bridge maintenance.

"The salts and stuff are not good on our bridges any way," Liles said. "It rusts our steels and it gets into our reinforcing steels and stuff like that. So, with it being as long as it is and being close to the river, we have to put more salts on it any way."

The double-decker bridge, built between 1977-1986, is 1.1 miles long and has about 17,000 cars on it daily. Liles says the alternatives to that bridge not only keep that high traffic volume flowing through that area, but could also drive more traffic into downtown and maybe even lead to more development.

"Some of these alternatives allows for the traffic movement that is still there," he said. "It also allows for some potential economic development and economic drivers. Even some revitalization of the downtown."

What started as 19 alternatives was narrowed down to five in August and now three in September. Liles says MoDOT hopes to have their top alternative choice by the end of 2021.

"Probably some time between now and the end of the year, we want to come up with what we call a 'preferred alternative,'" he said. "We want to present that to the public. We want to talk with our Federal Highway Administration, make sure we're on the same page and kind of wrap this environmental study up."

Construction timeline and cost hasn't even been thought about yet. That'll be a whole separate process after the final alternative is decided on and approved. MoDOT will be responsible for coming with the funding, whatever is decided.

While the idea of revitalizing downtown St. Joseph is a big potential gain from this project, MoDOT wants to be sure their alternatives are environmentally friendly, fiscally responsible and don't cause too many  structures to be relocated.

Whether the current double-decker is kept, or an alternative is built, Liles says they want to keep the purpose of that section of I-229 the same.

"Its function of that double-decker is, really, moving people from the north end of St. Joe to the south end of St. Joe."

You can follow Tommy on Twitter @TommyKFEQ and St. Joseph Post @StJosephPost.