Interstate 229 Missouri

Overview

Interstate 229 forms an urban loop west from I-29 through the city of St. Joseph. The freeway carries four overall lanes with rural stretches leading through Buchanan County to the south and Andrew County to the north. Through Downtown and along the Missouri Riverfront, I-229 combines with U.S. 59 along a double deck freeway.

2015 traffic counts recorded by the Missouri Department of Transportation (MoDOT) peaked at 16,810 vehicles per day (vpd) east of Exit 1 D (Route 752), while the roadway north of Exit 11 (Highway K) was lightly traveled with just 4,646 vpd. St. Joseph is also served by a business loop from Interstate 29 along a combination of streets and shared alignments with U.S. 59 and U.S. 169.

An emergency closure of the double deck section of I-229 followed reports of falling debris recorded on June 4, 2015 (Scherer, 2015). The aging structure and increasing repair costs to maintain resulted in the Missouri Department of Transportation (MoDOT) reevaluating the future of the route. A 2016 estimate for a major rehabilitation of the bridge was about $50 million. The work would extend the lifespan of the elevated structure by 20 to 25 years. However, an alternative discussed by city leaders, highway engineers and residents involved replacing the freeway with an at-grade parkway. Costing less to maintain, the non-freeway design may also open up riverfront areas for redevelopment (Lauck, 2006).

Originally planned for a 16 to 18 month period, a Missouri Department of Transportation (MoDOT) study with public input considered an array of alternatives for the future of Interstate 229 through St. Joseph. Options ranged from retaining the existing Double Decker Bridge, replacing it with a new elevated structure, removing it and partitioning I-229 into separate spurs into Downtown, or replacing I-229 with an at-grade boulevard or a parkway option with roundabouts. Other options considered upgrading existing streets through Downtown with the elevated structure demolished.

MoDOT proceeded with plans for the removal of the Double-Decker Bridge along the Missouri River and replacement with a four-lane arterial. An Environmental Assessment (EA) was completed in 2025, and Alternative D was selected. A Finding of No Significant Impact (FONSI) was subsequently issued by the Federal Highway Administration (FHWA) for the preferred alternative. Dubbed I-229 Moving Forward, the project calls for dropping the entire route of I-229 from the Interstate Highway System and constructing an at-grade arterial along the Double_Decker Bridge right-of-way (MoDOT, 2026). A diamond interchange will be built where U.S. 59 ties into the elevated structure from the northeast. A signalized intersection will be constructed with the arterial at SR 759.

Initial survey data collection and conceptual design work for the I-229 Moving Forward project was underway as of Summer 2026. Formal project design was anticipated for 2027 to 2028, followed by two years of construction (MoDOT, 2026).

History

Lobbying efforts from the publisher of the News-Press, Henry D. Bradley and others pushed for Interstate 229 through St. Joseph. The route was intended to draw traffic back into St. Joseph that was otherwise bypassing the city to the east along I-29. Land acquisition difficulties led to the double deck design through the Downtown area as a way to complete the route (Heater, 2016).

Interstate 229 opened initially from I-29 south of St. Joseph to Missouri Route 371 (S 22nd Street) by 1970. Costing $20 million, the double deck section of I-229 was built in phases between 1977 and 1986. A weather-damaged portion of the viaduct was completed in 1979 (Scherer, 2015) (Lauck, 2006).

North End  ‐ Amazonia, MO

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Interstate 229 rises from Dillon Creek by agricultural areas one mile ahead of Exits 14 A/B/C with I-29 and U.S. 59-71 north. 02/20/20

North at

One mile south from the return of Interstate 229 north from St. Joseph on I-29. 11/03/16

South at

U.S. 59/71 travel a freeway south from the Andrews County seat of Savannah that directly transitions onto Interstate 229 south at forthcoming Exit 56. 06/18/15

South at

U.S. 59/71 traverse hilly terrain south from Hopkins Creek to the unnumbered interchange with I-29 and I-229. 06/18/15

South End  ‐ St. Joseph, MO

South at

Exit 1 C departs I-229 south for Highway A (40th Street) to the south suburbs of St. Joseph. The freeway loop returns to I-29 in a half mile. 07/14/26

North at

I-29/U.S. 71 traverse a series of rural hills by the Pigeon Hill Conservation Area ahead of Interstate 229 and the St. Joseph area. 02/20/20

South at

I-29/U.S. 71 advance south from U.S. 169 and the end of Business Loop I-29 to a directional T interchange (Exit 43) with Interstate 229 leading back north to St. Joseph. Photo by Joseph Barnes (08/14/16).

South End – Past Views

Past Views Gallery (Tap to Expand / Collapse Section)

at

The final three ramps from Interstate 229 south were previously unnumbered. Replacement signage added by 2026 included exit numbers. 06/18/15