Interstate 129 Iowa / Nebraska

History

Western Terminus

Eastern Terminus

Routing

Interstate 129 crosses the Missouri River between Sioux City, Iowa, and South Sioux City, Nebraska. The highway is duplexed with U.S. 20 for its entire length, and it also shares roadway with U.S. 75. The highway is not signed well in Iowa (see photo below).

History

In Iowa, Interstate 129 was completed on November 22, 1976.¹

I-129 in Text

Looking at the photos of the eastern terminus of Interstate 129 as seen from northbound Interstate 29, one immediately notices that Interstate 129 is written in text. To resolve this question, we asked Iowa's Department of Transportation. Here is their response, from May 2007:

We received your comment concerning the use of the interstate shield for I-129 for southbound traffic and the use of letter text for I-129 for northbound traffic on I-29. Approximately 10+ years ago some motorists were getting confused with I-129 signing, thinking it was I-29 and taking the off ramp to US75 to Nebraska when they really wanted to stay on I-29. We thought we would try using the letter text I-129 to make it stand out different from the interstate shield of I-29.

Since then we have had a signing project on southbound I-29 and changed the letter text I-129 back to the interstate shield and have had no complaints or concerns that I’m aware of. The northbound signing on I-29 will be reviewed when we put our next project together.

Future Aspirations

Construction is underway to extend the U.S. 20 (east of Interstate 129) freeway from the east end near Business U.S. 20 north and westward to return to Interstate 29 in South Dakota. Upon completion of this freeway extension, Interstate 429 is proposed to be christened as a bypass of the Sioux City area. It remains to be seen if the Interstate 129 designation will be kept in any capacity if Interstate 429 is constructed.

	Western Terminus - U.S. 20-75-77 - South Sioux City, Nebraska Perspective from Interstate 129/U.S. 20 west and U.S. 75 south Interstate 129 is a very short freeway. Only two exits exist on the westbound route: Exit 2, Junction Business U.S. 20/Dakota Avenue to South Sioux City and Junction Nebraska 35 south to Dakota City, followed by the western terminus at Exit 1, Junction U.S. 77. Both of these exits serve South Sioux City. Photo taken by Alex Nitzman (04/20/07). A trailblazer for U.S. 75 south is posted shortly after the offramp to Business U.S. 20 east. U.S. 75 will leave Interstate 129 at Exit 1A. Photo taken by Alex Nitzman (04/20/07). The final interchange on Interstate 129 west is Exits 1B-A, Junction U.S. 77. Southbound U.S. 75 will depart the freeway south toward Winnebago. U.S. 77 north travels into Sioux City, Iowa, where it ends at Interstate 29 Exit 148. Photo taken by Alex Nitzman (04/20/07). This is the final reassurance shield on westbound Interstate 129 and U.S. 20-75. Exit 1 can be seen in the distance. Photo taken by Alex Nitzman (04/20/07). Westbound Interstate 129/U.S. 20 and southbound U.S. 75 reaches Exit 1B, U.S. 77/Wesley Way north. The final exit is Exit 1A, Junction U.S. 75-77 south to Winnebago. The pull-through sign only advises of U.S. 20 west, with no control city. Photo taken by Alex Nitzman (04/20/07). Shortly thereafter, westbound Interstate 129 and U.S. 20 split with U.S. 75 north. Exit here for U.S. 75-77 south to Winnebago. Photo taken by Alex Nitzman (04/20/07). Perspective from Interstate 129/U.S. 20 west This "END" Interstate 129 sign was located just west of the U.S. 75/77 cloverleaf interchange in South Sioux City, Nebraska. However, the sign was gone by April 2007. Interstate 129 is one of those rare three-digit interstates that enters a state that its parent route (Interstate 29) does not enter. Photo taken by Jeff Morrison and Jason Hancock (06/12/05). Shortly after the former END sign is this new END Interstate 129 shield assembly, which is coupled with the U.S. 20 west reassurance shield that was seen in the prior picture. Photo taken by Alex Nitzman (04/20/07). A zero milepost for Interstate 129 is posted shortly after the END shield for Interstate 129. U.S. 20 continues west from here, preparing the cross the Cornhusker State of Nebraska before entering the Equality State of Wyoming. Cities along the way to Wyoming include O'Neill, Valentine, and Chadron. Photo taken by Alex Nitzman (04/20/07). Perspective from U.S. 77/Wesley Way south The junction between U.S. 77 and Interstate 129/U.S. 20-75 is the Kingsbury Interchange. The first ramp connects to U.S. 20 west, and the second ramp loops onto Interstate 129/U.S. 20 east. Photo taken by Alex Nitzman (04/20/07). An Interstate 129 and U.S. 20 junction shield assembly is posted shortly thereafter on southbound U.S. 77/Wesley Way. Photo taken by Alex Nitzman (04/20/07). Looking south on U.S. 77, the first exit on the cloverleaf interchange is the ramp to U.S. 20 west, followed by Interstate 129 and U.S. 20 east to Sioux City, Iowa. Photo taken by Alex Nitzman (04/20/07). An Interstate 129 east trailblazer shield is posted after the U.S. 20 west ramp. Photo taken by Alex Nitzman (04/20/07). Southbound U.S. 77 reaches the loop ramp to Interstate 129/U.S. 20 west and U.S. 75 south. Continue straight ahead to follow U.S. 75-77 south to Winnebago. Photo taken by Alex Nitzman (04/20/07). Perspective from U.S. 77/Wesley Way north The junction between U.S. 77 and Interstate 129/U.S. 20-75 is the Kingsbury Interchange. The first ramp connects to Interstate 129/U.S. 20 east and U.S. 75 north, and the second ramp connects to U.S. 20 west. Photo taken by Alex Nitzman (04/20/07). The right lane becomes exit only for the connection to Interstate 129 and U.S. 20-75 east to Sioux City, Iowa. Photo taken by Alex Nitzman (04/20/07). A trailblazer shield for U.S. 75 north is posted for the connection to Interstate 129/U.S. 20 east. U.S. 75 will follow U.S. 20 east into Iowa, then carry the belt route to the east of Sioux City, Iowa. Photo taken by Alex Nitzman (04/20/07). The right lane splits off from northbound U.S. 77 to Interstate 129/U.S. 20-75 east. Continue straight ahead to follow U.S. 77/Wesley Way north into South Sioux City. Photo taken by Alex Nitzman (04/20/07). Shortly thereafter, northbound U.S. 77/Wesley Way reaches the loop ramp to U.S. 20 west to O'Neill. Continue straight on U.S. 77 north to South Sioux City. Photo taken by Alex Nitzman (04/20/07). Perspective from U.S. 20 east Traveling east on U.S. 20, the first advance signage for Interstate 129 and U.S. 75-77 is this sign for Exits 1A-B, Junction U.S. 77/Wesley Way north to Sioux City and south to Winnebago. Photos taken by Alex Nitzman (04/20/07) and Jeff Morrison and Jason Hancock (06/12/05). The first ramp of the interchange connects to Exit 1A, Junction U.S. 75-77 south to Winnebago. Photo taken by Alex Nitzman (04/20/07). Perspective from Interstate 129/U.S. 20 east and U.S. 75 north Interstate 129 east begins as U.S. 20 east meets U.S. 75-77 at Exit 1. Use U.S. 77 north into South Sioux City, Nebraska; continue east on Interstate 129/U.S. 20 to Sioux City, Iowa, and destinations served by Interstate 29. This is a cloverleaf interchange. The sign should also include U.S. 75 south, but the sign predates when U.S. 75 was merged onto Interstate 129 to bypass South Sioux City in Nebraska. Photo taken by Alex Nitzman (04/20/07). At the loop ramp from eastbound Interstate 129 and U.S. 20 to U.S. 77, this mileage sign provides the distance to the next two exits: Exit 2, Junction Business U.S. 20 and Nebraska 35/Dakota Avenue, followed by Exits 1A-B, Junction Interstate 29 and Business U.S. 75 in Iowa. Photo taken by Alex Nitzman (04/20/07). The first reassurance shield for Interstate 129 east, U.S. 20 east, and U.S. 75 north is posted shortly thereafter. Photo taken by Alex Nitzman (04/20/07). The next exit along eastbound Interstate 129/U.S. 20 is Exit 2, Junction Business U.S. 20/Dakota Avenue north to South Sioux City and Junction Nebraska 35 south to Dakota City. Photo taken by Alex Nitzman (04/20/07). Shortly after its western terminus, eastbound Interstate 129 and U.S. 20-75 starts showing the distance to its parent route, Interstate 29. This sign is in Nebraska. Photo taken by Alex Nitzman (04/20/07). This is the second complete shield assembly for eastbound Interstate 129 and U.S. 20-75, about midway between the U.S. 77 and Interstate 29 interchanges in Nebraska after Exit 2. Photo taken by Jeff Morrison and Jason Hancock (06/12/05). Eastern Terminus - Interstate 29 - Sioux City, Iowa Perspective from Interstate 129/U.S. 20 east and U.S. 75 north Now traveling east, this Interstate 29 guide sign is posted after the onramp from Dakota Avenue (Business U.S. 20 and Nebraska 35). The final exit on eastbound Interstate 129 is the interchange with Interstate 29 in Iowa. Photo taken by Alex Nitzman (04/20/07). Preparing to ascend the bridge over the Missouri River, a "Sioux City Next 5 Exits" sign is posted. This sign includes the final exit on eastbound Interstate 129 (Junction Interstate 29) as well as the next four exits on U.S. 20 and U.S. 75 around the belt route. Photo taken by Alex Nitzman (04/20/07). Welcome sign and Exit 1B/Interstate 29 north overheads on Interstate 129 eastbound as it crosses from Nebraska. As shown in the mileage table above, less then one-third of a mile remains of Interstate 129 eastbound. Photo taken by Alex Nitzman (04/20/07). Notice that U.S. 20 continues eastward with no mentioning that Interstate 129 has terminated. U.S. 20 east remains a freeway (or divided highway) for much of its journey across the northern tier of Iowa. Also notice that an End Interstate 129 shield is posted (complete with the Iowa state name). Photo taken by Alex Nitzman (04/20/07). Here is a close-up of the END Interstate 129 shield along eastbound at the Interstate 29 interchange. Photo taken by Jeff Royston (03/16/05). Perspective from Interstate 29 north Meanwhile, along northbound Interstate 29, the first indication of Interstate 129 is at the Exit 143 interchange (Junction Business U.S. 75/Singing Hills Boulevard). Singing Hills Boulevard is formerly U.S. 75, but U.S. 75 has been moved to the eastern Sioux City bypass. Photo taken by Alex Nitzman (04/20/07). A roadside sign advises that Exit 144B (loop ramp) connects to South Sioux City, Nebraska. This is the ramp to Interstate 129 west. Photo taken by Alex Nitzman (04/20/07). Northbound Interstate 29 reaches Exit 144A, Junction U.S. 20 East and U.S. 75 North, the Sioux City Bypass. The next exit on this interchange is Exit 144B, Junction Interstate 129 and U.S. 20 West and U.S. 75 South. Photo taken by Alex Nitzman (04/20/07). Immediately thereafter, northbound Interstate 29 reaches Exit 144B, Junction Interstate 129 and U.S. 20 West and U.S. 75 South. Photo taken by Alex Nitzman (04/20/07). Perspective from Interstate 29 south This photo shows the progression of signs on southbound Interstate 29 as it approaches its junction with Interstate 129 westbound and U.S. 20-75 eastbound. This photo shows an older sign assembly; notice that Interstate 129 is displayed in text rather than with a standard Interstate shield. Photo taken by J.P. Nasiatka (5/01). Replacement signage was put in place at the south Interstate 29 transition ramp to eastbound Interstate 129 as shown here as a result of the recently constructed U.S. 75 bypass which skirts the eastern edge of the Sioux City metropolitan area. Interstate 129 is again shown with a shield rather than in text. Photo taken by Jeff Royston (03/18/05). Perspective from U.S. 20 west and U.S. 75 south Now traveling west on U.S. 20 and south on U.S. 75 after the Lakeport Road interchange, the Sioux City belt route freeway approaches its interchange with Interstate 29 and Interstate 129. For all of the approach signs to this interchange, Interstate 129 is not mentioned at all. Photo taken by Alex Nitzman (04/20/07). The right lane becomes exit only for the connection to Interstate 29 north and south. The left two lanes will connect directly onto Interstate 129 west. Photo taken by Alex Nitzman (04/20/07). High mast lighting provide illumination at night at the interchange between U.S. 20-75 and Interstate 29. Use Interstate 29 south to the airport. Photo taken by Alex Nitzman (04/20/07). Westbound U.S. 20 and southbound U.S. 75 reach Exit 1, Junction Interstate 29 north and south. Once on the transition ramp, use the left lane to Interstate 29 south and the right lane to Interstate 29 north. Continue straight ahead to Interstate 129 west to South Sioux City, Nebraska. Photo taken by Alex Nitzman (04/20/07). Once on the transition ramp to Interstate 29, note the remnants of a "U.S. 75 north" shield assembly pasted onto the sign that has since been removed. This reflects the prior routing of U.S. 75 through Sioux City; today, U.S. 75 follows the belt route to the east of the city. Photo taken by Alex Nitzman (04/20/07). Perspective from Interstate 129/U.S. 20 west and U.S. 75 south Upon crossing Interstate 29, the first sign is for the Missouri River, meaning that Interstate 129 spends a very short time in Iowa and immediately climbs the bridge to take it into Nebraska. Photo taken by Alex Nitzman (04/20/07). Only U.S. 20 west and U.S. 75 south are signed between the Interstate 29 interchange and Missouri River Bridge in Iowa. Interstate 129 is better signed in Nebraska. The welcome sign is posted immediately after this sign bridge. Photo taken by Alex Nitzman (04/20/07). Westbound Interstate 129 and U.S. 20-75 crosses the Missouri River and enters the Cornhusker State of Nebraska, leaving the Hawkeye State of Iowa. Photo taken by Alex Nitzman (04/20/07). The first exit on Interstate 129 and U.S. 20-75 west is Exit 2, Junction Business U.S. 20/Dakota Avenue to South Sioux City and Junction Nebraska 35 south to Dakota City. Photo taken by Alex Nitzman (04/20/07). Shortly thereafter, the first reassurance shield for Interstate 129 west, U.S. 20 west, and U.S. 75 south is posted. In the distance is an overpass, followed by Exit 2, Junction Business U.S. 20/Dakota Avenue to South Sioux City and Junction Nebraska 35 south to Dakota City. Photo taken by Alex Nitzman (04/20/07). Interstate 129 is a very short freeway. Only two exits exist on the westbound route: the local exit to South Sioux City and Dakota City, followed by the western terminus at Exit 1, Junction U.S. 77. Both of these exits serve South Sioux City. Photo taken by Alex Nitzman (04/20/07).

Sources:

1. Iowa Interstate - 50th Anniversary (web site no longer online)

Page Updated July 22, 2007.