Interstate 29 in Iowa

Interstate 29
Iowa's Interstate Highways with I-29 highlighted in red.
Route information
Maintained by Iowa DOT
Length:	151.826 mi[1] (244.340 km)
Existed:	October 1, 1958[2] – present
History:	Under construction 1958–1972
Tourist routes:	Lewis & Clark Trail
Major junctions
South end:	I-29 near Hamburg
	Iowa 2 near Percival US 34 near Glenwood I‑80 overlap at Council Bluffs I‑480 / US 6 at Council Bluffs I‑680 overlap US 30 at Missouri Valley I‑129 / US 20 / US 75 at Sioux City US 77 in Sioux City
North end:	I-29 at Sioux City
Location
Counties:	Fremont Mills Pottawattamie Harrison Monona Woodbury
Highway system
Interstate Highway System Main Auxiliary Suffixed Business Iowa Primary Highway System Interstate U.S. State Secondary Scenic ← Iowa 28 US 30 →

In the U.S. state of Iowa, Interstate 29 (I-29) is a north–south Interstate Highway which closely parallels the Missouri River. I-29 enters Iowa from Missouri near Hamburg and heads to the north-northwest through the Omaha-Council Bluffs and the Sioux City areas. It exits the state by crossing the Big Sioux River into South Dakota. For its entire distance through the state, it runs on the flat land between the Missouri River and the Loess Hills.

I-29 was built in sections over a period of 15 years. When there was a shortage of male workers, female workers stepped in to build a twenty-mile (32 km) section near Missouri Valley. Between Council Bluffs and Sioux City, I-29 replaced U.S. Route 75 (US 75) as the major route in western Iowa. As a result of I-29's creation, US 75 south of Sioux City was relocated into Nebraska.

Route description

Interstate 29 enters Iowa south of Hamburg. The interstate heads northwest, where it meets Iowa Highway 333 (Iowa 333) at a diamond interchange. From Hamburg, I-29 continues to the northwest for seven miles (11 km) where it meets Iowa 2 three miles (4.8 km) east of Nebraska City, Nebraska. North of the Iowa 2 interchange, the interstate straightens out to the north; interchanges serving Percival, Thurman, and Bartlett are spaced out every four and a half miles (7.2 km). At the US 34 interchange near Glenwood, I-29 is joined by US 275.^[1]

I-29 is flanked by the Loess Hills

North of Glenwood, I-29 / US 275 continue north towards Council Bluffs. The two routes meet Iowa 370, which crosses into Nebraska providing access to Offutt Air Force Base in Bellevue, Nebraska. Near Lake Manawa, US 275 splits away from I-29 at the Iowa 92 interchange. three-quarters mile (1.2 km) north of the split, the interstate is joined from the east by Interstate 80. The two interstates head west together through southern Council Bluffs for three miles (4.8 km). When the two interstates split at a Y interchange, I-80 immediately crosses the Missouri River into Nebraska, and I-29 immediately turns to the north. Two miles (3.2 km) to the north is a modified Y interchange with US 6 and the eastern end of I-480.^[1]

North of Council Bluffs, I-29 is joined by I-680 near Crescent. The two interstates travel north together for nine miles (14 km) before I-680 splits off to the east near Loveland. I-29 continues north for four miles (6.4 km) to Missouri Valley, where it intersects US 30. North of Missouri Valley, the interstate turns to the northwest towards Modale and then straightens out again south of Mondamin, where I-29 meets the western end of Iowa 127. From Mondamin, it travels north for 23 miles (37 km) to the Iowa 175 interchange at Onawa, passing Little Sioux and Blencoe.^[1]

Interstate 29 closely parallels the Missouri River in Sioux City

North of Onawa, I-29 continues northwest for fifteen miles (24 km) towards Sloan, where it meets the western end of Iowa 141. As it approaches the Sioux City metro area, it passes the Sioux Gateway Airport at Sergeant Bluff. At the Singing Hills Boulevard interchange, northbound is joined by southbound U.S. Route 75 Business (US 75 Bus.). One mile (1.6 km) later, US 75 Bus. ends at the cloverleaf interchange with US 20 / US 75, which is also the eastern end of Interstate 129.^[1]

For the next three miles (4.8 km) north of the I-129 interchange, I-29 runs closely, as close as 200 feet (61 m), to the Missouri River. The interstate follows the curve of the river and turns to the west. It meets Gordon Drive, which carries US 20 Bus. US 20 Bus. traffic is directed onto the interstate for one-half mile (0.80 km) before it exits via a volleyball interchange which represents the national northern end of U.S. Route 77.^[1] I-29 continues west along the Missouri River, and after the Big Sioux River converges into the Missouri, I-29 follows the Big Sioux. Shortly before it crosses the Big Sioux into South Dakota, Iowa 12 splits away to the north.^[3]

History

Interchange with 680 looking toward the Mormon Bridge in Council Bluffs on June 16, 2011 during the 2011 Missouri River floods

Construction of Interstate 29 began in the late 1950s in the Sioux City area. The first section to open, a three-mile-long (4.8 km) stretch from the Big Sioux River to the then-US 20 / US 77 bridge across the Missouri River, opened around October 1, 1958. In September 1961, I-29 was extended across the Big Sioux River to South Dakota. On April 1, 1962, some of the northbound directional spans collapsed into the Big Sioux River at the South Dakota state line as a result of flooding and bridge scour.^[4][5][6]

North of Council Bluffs, a twenty-mile (32 km) section to Missouri Valley opened in November 1958. By December 1967, the two sections were connected, creating 100 miles (160 km) of continuous interstate highway.^[2] Due to a shortage of male workers, at least 20 women were enlisted to help build this section of I-29. The women were paid $2.00 hourly ($14.00 hourly in 2016 dollars^[7]), the same wage as men would have earned.^[8]

Construction of I-29 in the Council Bluffs area was completed in 1970 and the route was open to Glenwood in the same year. Additional interchanges were added in the Sioux City and Council Bluffs areas between 1970 and 1971. The last thirty miles (48 km) of interstate were constructed and opened in sections over the next two years; the last section opened on December 15, 1972.^[2]

In 1973, US 34 was expanded to four lanes near Glenwood, which resulted in US 34 being rerouted onto I-29 for three miles (4.8 km).^[2] In 2003, US 275 was rerouted onto I-29 from the same interchange near Glenwood northward to Iowa 92 at Council Bluffs. The former US 275 alignment was turned over to Mills and Pottawattamie Counties.^[9]

Much of I-29 was built next to existing highways, most notably US 75. When the section of I-29 opened between Council Bluffs and Missouri Valley, US 75 was rerouted onto I-29.^[10] When construction connecting the Sioux City and Council Bluffs segments was completed, US 75 was again rerouted onto I-29.^[11] In the mid-1980s, US 75, from Council Bluffs to Sioux City, was completely rerouted out of Iowa, instead extending up the former US 73 corridor in Nebraska.^[12]

Exit list

County	Location	mi[1]	km	Exit[13]	Destinations	Notes
Fremont	Washington Township	0.000	0.000		I-29 south – St. Joseph, Kansas City	Continuation into Missouri
		1.811	2.915	1	Iowa 333 east – Hamburg	Access to Grape Community Hospital
	Benton Township	10.144	16.325	10	Iowa 2 – Sidney, Nebraska City
		15.458	24.877	15	CR J26 – Percival
	Scott Township	19.917	32.053	20	CR J24 – McPaul, Thurman	Formerly Iowa 145
		24.447	39.344	24	CR L31 (To CR J10) – Bartlett, Tabor
Mills	Plattville Township	32.386	52.120	32	Pacific Junction, Plattsmouth	Formerly US 34
		35.477	57.095	35	US 34 / US 275 south – Glenwood, Red Oak	Southern end of US 275 overlap
	Saint Marys–Oak township line	43.805	70.497	42	CR H10 – Bellevue, Neb., Offutt Air Force Base	Formerly Iowa 370
Pottawattamie	Council Bluffs	47.865	77.031	47	US 275 north / Iowa 92 – Lake Manawa	Northern end of US 275 overlap
		48.526	78.095	48	I‑80 east – Des Moines	Southern end of I-80 overlap; I-80 exit 4
		49.230	79.228	3	Iowa 192 north (South Expressway) – Council Bluffs, Business District, Lake Manawa	Exit number follows I-80
		50.683	81.566	1B	S. 24th Street – Mid-America Center	Exit number follows I-80
		51.644	83.113	51	I‑80 west – Omaha	Northern end of I-80 overlap; I-80 exit 1A
		52.378	84.294	52	Nebraska Avenue
		53.199	85.615	53A	9th Avenue / Harrah's Boulevard
		53.777	86.546	53B	I‑480 / US 6 west – Omaha	Clockwise terminus of I-480; northbound left exit; no access to US 6 east; serves Eppley Airfield
		54.204	87.233	54A	Avenue G	Southbound exit and entrance only
		54.623	87.907	54B	N. 35th Street	Northbound exit and entrance only
		55.715	89.665	55	N. 25th Street
		56.917	91.599	56	Iowa 192 south – Business District, Council Bluffs	Southbound left exit and northbound entrance only
	Crescent Township	61.966	99.725	61	I‑680 west / CR G37 east – Crescent, North Omaha	Southern end of I-680 overlap; signed as exits 61A (east) and 61B (west)
	Crescent–Rockford township line	66.465	106.965	66	Honey Creek
	Rockford Township	71.623	115.266	71	I‑680 east – Des Moines	Northern end of I-680 overlap
		71.988	115.853	72	Loveland	Pottawattamie CR G12 (west) and CR G14 (east)
Harrison	Missouri Valley	75.786	121.966	75	US 30 – Missouri Valley, Blair	Access to Community Memorial Hospital
	Taylor Township	82.088	132.108	82	CR F50 – Modale
	Morgan Township	89.309	143.729	89	Iowa 127 east – Mondamin
	Little Sioux Township	95.714	154.037	95	CR F20 – Little Sioux
Monona	Sherman Township	105.347	169.540	105	CR K45 – Blencoe
	Onawa	112.326	180.771	112	Iowa 175 – Onawa, Decatur
	Lincoln–Lake township line	120.210	193.459	120	CR E24 – Whiting
Woodbury	Sloan Township	127.571	205.306	127	Iowa 141 east – Sloan
	Salix	133.970	215.604	134	Salix (CR K25)
		135.708	218.401	135	Port Neal Landing (CR D51)
	Sergeant Bluff	141.194	227.230	141	CR D38 – Sergeant Bluff, Sioux Gateway Airport
	Sioux City	143.413	230.801	143	US 75 Business (Singing Hills Boulevard)
		144.473	232.507	144	I‑129 west / US 20 / US 75 – Le Mars, Fort Dodge, South Sioux City	Signed as exits 144A (east/north) and 144B (west/south); I-129 exits 1A-B
		147.476	237.340	147A	Floyd Boulevard
		148.050	238.263	147B	Gordon Drive (US 20 Business east) – Downtown, Tyson Events Center	No northbound entrance; access to Mercy Medical Center and St. Luke's Regional Medical Center
		148.493	238.976	148	US 77 south (Wesley Parkway / US 20 Business west) – South Sioux City, Nebr.	No southbound exit; southbound access is part of exit 149
		149.081	239.923	149	To US 77 south (Wesley Parkway / US 20 Business west) / Hamilton Boulevard – South Sioux City, Nebr.	Northbound exit signed as Hamilton Blvd. only
		151.365	243.598	151	Iowa 12 north (Riverside Boulevard) – Akron
Big Sioux River		151.826	244.340	Iowa–South Dakota state line
Union	Dakota Dunes				I-29 north – Sioux Falls	Continuation into South Dakota
1.000 mi = 1.609 km; 1.000 km = 0.621 mi       Concurrency terminus       Incomplete access

References

1. "2009 Volume of Traffic on the Primary Road System of Iowa" (PDF). Iowa Department of Transportation. January 1, 2009. Retrieved September 8, 2010.
2. Completion Map of Interstate System (PDF) (Map). Iowa Department of Transportation. January 1, 1982. Retrieved September 8, 2010.
3. Sioux City, Iowa (PDF) (Map). Iowa Department of Transportation. 2010. Retrieved September 8, 2010.
4. "Rain, storms follow weekend of storms; stir fears of floods". Lodi News-Sentinel. United Press International. April 2, 1962. p. 5. Retrieved January 29, 2015.
5. "I-29 bridge collapse". Sioux City Journal. April 22, 2012. Retrieved January 29, 2015.
6. Richardson, E. V.; Lagasse, P. F. (1999). Stream Stability and Scour at Highway Bridges. American Society of Civil Engineers. p. 57.
7. "Consumer Price Index (estimate) 1800–". Federal Reserve Bank of Minneapolis. Retrieved November 10, 2015.
8. "Can't get men, paving contractor is hiring women". Toledo Blade. Associated Press. October 13, 1967. p. 5. Retrieved September 8, 2010.
9. Iowa State Highway Map (PDF) (Map). Iowa Department of Transportation. 2004. § B2. Retrieved September 8, 2010.
10. Iowa State Highway Map (PDF) (Map). Iowa State Highway Commission. 1959. § L2:M3. Retrieved September 8, 2010.
11. Iowa State Highway Map (PDF) (Map). Iowa State Highway Commission. 1969. § G1:L3. Retrieved September 8, 2010.
12. Iowa State Highway Map (Map). Iowa Department of Transportation. 1985. § A5:B3.
13. Transportation Map (PDF) (Map). Iowa Department of Transportation. 2010. Retrieved 2010-09-08.

External links

Route map: Bing / Google

• The Iowa Highways Page (I-29)