I-380 highlighted in red | ||||
| Route information | ||||
| Auxiliary route ofI-80 | ||||
| Maintained byIowa DOT | ||||
| Length | 72.969 mi[1] (117.432 km) | |||
| Existed | c. September 19, 1973[2]–present | |||
| History | Under construction 1973–1985 | |||
| NHS | Entire route | |||
| Major junctions | ||||
| South end | ||||
| Major intersections |
| |||
| North end | ||||
| Location | ||||
| Country | United States | |||
| State | Iowa | |||
| Counties | ||||
| Highway system | ||||
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Interstate 380 (I-380) is a 73-mile (117 km)auxiliary Interstate Highway in easternIowa. The route extends fromI-80 nearCoralville toWaterloo. I-380 connects the cities ofCedar Rapids and Waterloo, the state's second- and sixth-largest cities, respectively, to theInterstate Highway System. Except for its last 1.5 miles (2.4 km) north ofU.S. Highway 20 (US 20), I-380 runs concurrently withIowa Highway 27 (Iowa 27), which represents Iowa's portion of the 560-mile (900 km)Avenue of the Saints highway connectingSaint Louis, Missouri, withSaint Paul, Minnesota.
Construction of I-380 took 12 years to complete, ending in 1985. After the Interstate opened,US 218 was moved onto the new freeway south of Cedar Rapids. In the 1990s, the I-380 corridor was selected as part of the Avenue of the Saints corridor, which Iowa designated as Iowa 27 in 2001. I-380 has been affected by two major floods, theGreat Flood of 1993 and theIowa flood of 2008, both of which closed the road at theIowa River for two weeks.
I-380 begins where US 218 andIowa 27 cross I-80 in Coralville inJohnson County. From the interchange, I-380, US 218, and Iowa 27, the route assigned to the Avenue of the Saints highway in Iowa runconcurrently toward Cedar Rapids. The Interstate heads north and servesNorth Liberty. North of North Liberty, the freeway runs parallel to the former routing of US 218 andIowa 965; here, the two highways cross the Iowa River. After crossing intoLinn County, the three routes enter the Cedar Rapids city limits nearEastern Iowa Airport. Three miles (4.8 km) north of the airport, I-380 intersectsUS 30 andUS 151 at acombination interchange. At this interchange, US 218 splits away from I-380 and Iowa 27.[3]
Through Cedar Rapids, the I-380 freeway is elevated relative to the nearby streets and residential neighborhoods. As it approaches downtown and theCedar River, the freeway takes a tight, 90-degree turn to the east, crosses the river and squeezes between aQuaker Oats Company plant andAlliant Energy PowerHouse, before turning back 90 degrees to the north. Between downtown and the Coldstream–29th Street interchange, I-380 serves as a dividing line between residential areas to the east and industry to the west. Toward the northern end of Cedar Rapids, industry is replaced with commerce as I-380/Iowa 27 meetIowa 100, locally known as Collins Road, at avolleyball interchange.[4]
The freeway leaves Cedar Rapids and entersHiawatha, where there are two interchanges, one at Blairs Ferry Road, which shares a southbound collector ramp with Collins Road, but has its own exit and entrance ramps. There is also adiamond interchange with Tower Terrace Road, before continuing northbound. Quickly escaping the Cedar Rapids area, I-380 turns to the northwest and passes through predominantly rural areas with small communities and farms dotting the way. Because of its northwestern angle, I-380 enters four counties within 30 miles (48 km), ascounties in Iowa are generally rectangular in shape. It passesCenter Point in northwestern Linn County,Urbana in northeasternBenton County, where it meetsIowa 150, andBrandon in southwesternBuchanan County. The Interstate travels intoBlack Hawk County, heading northwest for seven miles (11 km) before turning north for three miles (4.8 km) until adirectional T interchange with US 20.[3]
Together with US 20, I-380 and Iowa 27 travel west toward Waterloo andCedar Falls. The three routes pass the eastern Waterloo suburbs ofRaymond,Evansdale, andElk Run Heights. Almost immediately after crossing the Cedar River again, I-380 splits away from US 20 and Iowa 27 and rejoins US 218 at a three-level stack interchange. I-380 and US 218 head north to the east of theCrossroads Center shopping mall.[5] I-380 ends at thetraffic light at Mitchell Avenue one-half mile (800 m) north of the interchange which serves the Crossroads Center. US 218 continues to the north at this point.[6]

The first section of I-380 opened to traffic on September 19, 1973. That section connected Eastern Iowa Airport toI-80 at Coralville. Within three years, the Interstate had been extended into Cedar Rapids at the Cedar River. The bridge which crossed the river would not open until June 1979. By the end of 1981, I-380 was a continuous road to the Coldstream Avenue/Glass Road interchange.[2] The Interstate was originally scheduled to be open by December 25, 1984, but weather delays pushed back the construction timetable.[7] The last section of I-380 to be completed opened on September 12, 1985.[8]
In 1985, US 218 was bypassed around Iowa City and Coralville, joining I-380 at the I-80 interchange. US 218 to Cedar Rapids was replaced byIowa 965.[9] In the early 1990s, most of I-380 was designated as part of theAvenue of the Saints corridor, which connects Saint Louis, Missouri, to Saint Paul, Minnesota. Avenue of the Saints route markers were erected along the route the next year. In August 2001, the Avenue of the Saints in Iowa was given a single designation,Iowa 27, to facilitate following the route through the state.[10]
In 2019, theIowa Department of Transportation (Iowa DOT) began reconstructing I-80/I-380 interchange from its originally designedcloverleaf interchange into aturbine interchange.[11] During the construction process in March 2021, the eastbound ramps from I-80 utilized the new flyover bridges while transit from northbound US 218 to westbound I-80 required a detour via the next interchange at Forevergreen Road. The Iowa DOT projected frequent night closures of portions of the interchange to continue until completion of the upgrade, which was set to be completed in 2025.[12] However, the project was completed well ahead of schedule in late-August 2023.[13][14]
I-380 crosses two of Iowa's major rivers, theIowa andCedar rivers. Both rivers have affected the Interstate during major floods, as the case was in 1993 and 2008. During theGreat Flood of 1993, I-380 andIowa 965 were both closed at the Iowa River'sCoralville Lake reservoir between July 13 and 28.[15] The roads reopened after the lake's waters receded enough to allow Iowa DOT inspectors to check the three bridges over the water.[16]
TheIowa flood of 2008 affected the same section of I-380 at the Iowa River in much the same fashion as in 1993. I-380 and former Iowa 965 were closed at the Iowa River on June 13 until July 3.[17] In Cedar Rapids, flooding did not close I-380; the only bridge not to close, though traffic was restricted through the city.[18] The flooding damage was much more severe in Cedar Rapids than in Iowa City. The Cedar River crested at over 31 feet (9.4 m) on June 13, causing hundreds of millions of dollars in damage.[19]
In the Summer of 2024, IDOT began a $112 million project to repair roads and build additional lanes along I-380 from north ofNorth Liberty toCedar Rapids. A new diverging diamond interchange is also being built at Wright Brothers Boulevard near theEastern Iowa Airport.[20]
| County | Location | mi[1] | km | Exit[3] | Destinations | Notes | |
|---|---|---|---|---|---|---|---|
| Johnson | Coralville | 0.000 | 0.000 | Southern end of US 218/Iowa 27/AOTS overlap; continuation south of interchange | |||
| 97 0 | Southern terminus and signed as exit 0, northbound exit signed as 97; I-80 exit 239 | ||||||
| North Liberty | 2.040 | 3.283 | 2 | Forevergreen Road | |||
| 4.049 | 6.516 | 4 | |||||
| Jefferson Township | 10.863 | 17.482 | 10 | ||||
| Linn | Cedar Rapids | 13.821 | 22.243 | 13 | Ely,The Eastern Iowa Airport | FormerIowa 84 | |
| 16.332 | 26.284 | 16 | Northern end of US 218 overlap; northbound exits signed 16A (eastbound) and 16B (westbound) | ||||
| 17.590 | 28.308 | 17 | 33rd Avenue SW – Hawkeye Downs | ||||
| 18.346 | 29.525 | 18 | Wilson Avenue SW | ||||
| 19.417 | 31.249 | 19A | Northbound exit and southbound entrance only | ||||
| 19.752 | 31.788 | 19B | No southbound entrance, northbound exit signed as exit 19C | ||||
| 19C | 1st Street W | Northbound exit only | |||||
| 20.159 | 32.443 | 20A | No northbound exit | ||||
| 20.597– 20.651 | 33.148– 33.235 | 20B | 7th Street E –Alliant Energy PowerHouse | Entrances to highway are on 8th Street | |||
| 21.570 | 34.714 | 21 | H Avenue, J Avenue | J Avenue only signed northbound | |||
| 22.351– 22.676 | 35.970– 36.493 | 22 | Coldstream–29th Street; Glass Road – 32nd Street | ||||
| 23.377 | 37.622 | 23 | 42nd Street | Southbound access via exit 24B | |||
| 23.889 | 38.446 | 24A | Southbound access and northbound entrance via exit 24B | ||||
| Hiawatha | 24.372 | 39.223 | 24B | Blairs Ferry Road | |||
| 25.282 | 40.687 | 25 | Boyson Road | ||||
| 26.381 | 42.456 | 26 | Tower Terrace Road | Diverging diamond interchange (DDI) opened on June 22, 2023 | |||
| Monroe Township | 28.853 | 46.434 | 28 | ||||
| Center Point | 35.836 | 57.672 | 35 | FormerIowa 921 | |||
| Benton | Urbana | 41.876 | 67.393 | 41 | Urbana | FormerIowa 383 | |
| 43.545 | 70.079 | 43 | |||||
| Buchanan | Jefferson Township | 49.957 | 80.398 | 49 | Brandon | FormerIowa 283 | |
| Buchanan–Black Hawk county line | Jefferson–Spring Creek township line | 55.360 | 89.093 | 55 | |||
| Black Hawk | Fox Township | 62.231 | 100.151 | 62 | |||
| Poyner Township | 64.647– 65.820 | 104.039– 105.927 | 65 | Southern end of US 20 overlap | |||
| 66.495 | 107.013 | 66 | Raymond,Gilbertville | FormerIowa 297 | |||
| Evansdale | 68.402 | 110.082 | 68 | Evansdale Drive –Elk Run Heights | |||
| 70.674 | 113.739 | 70 | River Forest Road | ||||
| Waterloo | 71.179– 71.698 | 114.551– 115.387 | 71 | Northern end of US 20, Iowa 27, and AOTS overlaps; southern end of US 218 overlap; signed as exit 71A (US 218) and 71B (US 20/Iowa 27) | |||
| 72.390 | 116.500 | 72 | San Marnan Drive | FormerIowa 412 | |||
| 72.969 | 117.432 | Northern end of US 218 overlap; continuation beyond northern end | |||||
1.000 mi = 1.609 km; 1.000 km = 0.621 mi
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