"What happened?"
"The town was bypassed to save ten minutes of driving time."
--Disney/Pixar's "Cars" (2006)

Four-lane highway openings in Iowa by year and month

Credits for this page include Jason Hancock's website, Iowa state maps, newspaper articles, and the Iowa Interstate Completion Map available at the iowainterstate50th.com website (all interstates prior to 1982). Multiple entries in a month are listed in order of specific day of the month if known; italics at the end indicate expected openings. Interstate highways are shown in green, US highways in red, and state highways in blue. This map does not show multilane roads of a primarily urban nature, e.g. old US 218/University Avenue through Waterloo and Cedar Falls.

Early dates and unknowns

• 1942: US 34, Middletown to West Burlington (bypassed Nov/05)
• November 1949: US 75, north side Sioux City to Hinton - oldest rural four-lane segment in Iowa in use as of 2006, but wholly reconstructed and leveled out in 2019
• December 1949: US 75, Hinton to Merrill - will be reconstructed and leveled out in 2023
• June 1954: US 34, 2 miles east of Ottumwa (narrow median) (bypassed Oct/06)
• Unknown, late 1950s: US 20, segment in Dubuque
• June 29, 1956: Eisenhower signs law to create interstate highway system

• Unknown: US 61/151, Grandview Avenue to south split (Dbq) (north half w/US 52) (narrow median)
• June: US 75, Merrill to Le Mars (northern third bypassed Nov/06)
• December: US 77/US 20 [I-29], Hamilton Boulevard to Gordon Street, including interchange at bridge

• September: US 20, Nevada Street in Waterloo to Elk Run Heights (bypassed Sep/85); I-80, Douglas Avenue to west mixmaster (DM); I-35, Douglas Avenue to Cumming [G14] (#65)
• October: I-35, Cumming to IA 92; US 20, 3 miles east of Moville
• November: I-29, US 77/IA 12 (#151) to US 20 (#147B); I-35/80, Douglas Avenue to Merle Hay Road (DM); I-29, US 30 to US 75 [IA 192] (#56); I-35, IA 92 to north of Osceola [IA 152]; US 34, 3 miles west of Agency (was 2 lanes since Sep/55; bypassed Oct/06)

• August: US 20, 3 miles west of Dubuque
• November: I-29, SC industrial area [Business US 75] (#143) to IA 140 [IA 141] (#127); I-35/80, Merle Hay Road to US 69 (DM); I-80, US 6 [G30] (#75) to IA 25

• July: I-29, US 20/77 to SC industrial area
• August: I-35, north of Osceola to US 34
• Second half of year: US 30, Dow City to Denison (most removed late 1970s)
• September: I-80, US 71 to US 6 (#75); I-80, IA 25 to US 6 [F60] (#100)
• November: I-80, US 69 to US 6 (#159); I-35, US 69 to east mixmaster (DM); US 169, north junction IA 5 [IA 7] to US 20 [Business 20]
• December: I-80, IA 38 (#267) to US 61; I-280, I-80 to US 6

• Unknown: US 63, US 218 to near IA 412 [US 20]; IA 415, south city limits of Ankeny (old IA 160 junction) to I-35/80
• October: I-29, IA 141 (#127) to IA 175
• December: I-235, Cottage Grove Avenue to Keosauqua Way; I-29, South Dakota to US 77/IA 12

• August: I-80, Herbert Hoover Highway [F44] (#249) to IA 38 (#267)
• October: I-80, US 6 (#159) to IA 14
• November: I-80, IA 14 to IA 146; I-80, IA 1 to Herbert Hoover Highway; US 20, 2.5 miles near Holstein (part w/US 59)

1963

• Unknown: US 63, north side of Ottumwa to Court Street
• November: I-235, Keo Way to East 6th Street; I-80, US 218 [old IA 965] (#240) to IA 1

• Unknown: IA 163, west side of Pleasant Hill to a bit east of Pleasant Hill
• June: US 34, west of Ottumwa to Church Street
• October: I-80, IA 146 to US 218
• November: US 20, Sioux City to Moville; US 30, Ogden to Ames; I-80, US 61 to US 67

• Unknown: IA 163, Pleasant Hill to IA 316
• November: I-35, US 30 to I-80; US 34, 3 miles near US 71
• December: I-80, US 59 to US 71

• September: US 63, Church Street to south side of Ottumwa
• October: All of I-480; I-80, US 67 to Illinois
• December: I-680, I-29 to I-80; I-80, I-680 to US 59; US 6 (#100) to west mixmaster (completes link from I-29 to I-35); I-235, 31st Street to Cottage Grove Avenue and East 6th Street to University Avenue

• Unknown: US 59/IA 141, north junction IA 141 to US 30 (map marks IA 4 [IA 39] to 30 until mid-'90s)
• December: I-235, 63rd Street to 31st Street and University Avenue to east mixmaster; I-35, US 20 [D28] (#144) to US 30; I-29, IA 175 to US 30; US 61/151, near Maquoketa Drive in Dubuque to Dubuque Airport; US 34, east junction US 63 to Roemer Avenue (Ottumwa)

• July: I-80, Madison Avenue to US 6 (#8) (CB)
• August: I-74, I-80 to US 6
• October: I-29, 16th Street to 9th Avenue (CB); I-235, west mixmaster to 63rd Street (completes I-235)
• December: US 20/IA 520, US 69 to I-35

• December: I-35, US 34 to IA 2; I-29, IA 192 to IA 370; I-80, IA 192 to Madison Avenue (CB); I-80, US 6 (#8) to I-680

• Unknown: US 30, Z24 to US 67; US 18, I-35 to Mason City; IA 9, IA 32 [IA 86] to US 71
• November: rest of I-29/80 duplex (CB)
• December: I-35, IA 2 to US 69 (state line); I-29, IA 370 to US 34 (#32)
• New interchange: I-29, D51/Port Neal (NW Salix)

• August: I-35, IA 9 to IA 106 [B35] (#193)
• September: I-74, US 6 to US 67
• November: I-29, 9th Avenue to I-80 (CB)
• December: US 65/69, south side of Des Moines to Indianola; I-29, US 34 (#32) to Thurman exit [J24] (#20)

• September: US 30, Elwood Drive to Duff Avenue (US 69), provisional basis
• November: I-35, state line into Missouri
• December: I-35, Minnesota to IA 9; I-29, Thurman exit to Hamburg exit [IA 333] (#1); I-80, Nebraska to I-29 (completes I-80)

• Unknown: US 20, 1st Street in Cedar Falls to southeast of Waterloo Airport (part w/IA 57)
• Spring: US 30, full opening of Ames bypass
• August: I-29, Hamburg exit to Missouri (completes I-29)
• September: I-380, I-80 to Cedar Rapids Airport (#16)
• October: I-280, US 6 to Illinois

• February: US 34, Central Avenue to Main Street (Burl)
• Unknown: IA 13, Central City to US 151
• May: US 34/275, I-29 to east junction US 275
• November: US 20, IA 187 to IA 38; I-74, US 67 to Illinois

• Unknown: US 30, 6th Street SW to IA 13 (CR); US 65, I-80 to north side of Bondurant; IA 141, Granger to I-35/80
• June: US 34, US 61 to Central Avenue (Burl)
• September: US 30, US 61 [old IA 956] to Z24
• November: US 30 and US 61, De Witt bypass; I-35, IA 106 to US 20 [D28] (#144) (completes I-35)
• December: I-380, 5th Avenue SW to 33rd Avenue SW

• June: I-380, 33rd Avenue SW to Cedar Rapids Airport; US 20, Webster City to US 69
• November: US 34, West Burlington to US 61; all of I-129; US 20/IA 520, South Dakota to Lakeport Street (SC)

• Unknown: IA 141, IA 144 to US 169
• Fall: I-680, Nebraska to I-29 (completes I-680)

• Unknown: US 63, one additional mile north of Ottumwa to IA 389
• November: IA 5/92, Knoxville bypass

• June: I-380, 5th Avenue SW to 7th Street NE (CR); US 20, Sioux City bypass
• July: US 20, IA 150 to IA 187
• October: US 20, IA 17 duplex

• Only year since the mid-1950s in which NO new four-lane segments opened in Iowa, until 2013

• September: US 30/218, Stoney Point Road to 6th Street SW (CR)
• December: I-380, 7th Street NE to Glass Road/32nd Street (CR)

• November: US 218, F62 to IA 22; I-380, Glass Road/32nd Street to Boyson Road (CR)
• December: US 61, US 30 to I-80

• August: US 20, IA 297 [V49] to IA 150
• October: US 218, Riverside Drive to F62

• Unknown: IA 28, IA 5 to Norwalk
• August: US 20/IA 520, IA 21 to IA 297; I-380, north end to east junction US 20 and IA 150 to Boyson Road; US 218, Mitchell Avenue to Shaulis Road (most w/I-380)
• December: US 20/IA 520, US 63 to IA 21; US 61, Muscatine bypass

• June: US 218, I-80 to Riverside Drive
• September: I-380, east junction US 20 to IA 150 (completes I-380)

• June: US 20, Black Hawk/Grundy county line to US 63
• September: US 30/218, 16th Street SW to Stoney Point Road
• November: IA 2, Nebraska to I-29

• July: US 20, P59 to west junction IA 17
• November: US 20, IA 38 to Delaware/Dubuque county line

• May: US 20, Delaware/Dubuque county line to IA 136
• June: US 20, Y21 to segment that opened in 1959
• November: US 20, IA 136 to Y21 (completes Waterloo-Dubuque)

• October: US 218, IA 57 to Greenhill Road

• November: US 169, Business US 20 to US 20 (which opened three weeks later)
• December: US 20, US 169 to P59
• New interchange: I-74, 53rd Street (Davenport) (October 1)

• Unknown: US 63, C66 to Black Hawk/Bremer county line
• January: US 52/61/151, 4th Street to Grandview Avenue (Dbq)
• October: US 20, I-35 to R77
• November: US 218, I-380 to US 63 (northbound only)
• December: US 61/151, 11th Street to Wisconsin (Dbq)

• Unknown: US 30, R70 to Nevada; IA 163, IA 316 halfway to Prairie City
• Second half of year: US 30/218, IA 201 [W24] to Cedar Rapids bypass
• November: US 151, IA 13 to Springville; US 218, Greenhill Road to US 63 and southbound to I-380; US 71, Milford to US 18

• Unknown: IA 58, US 20 to University Avenue; US 61/218, duplex north of Keokuk
• August: US 52/61/151: 4th Street to 11th Street (Dbq)
• October: US 34, Main Street to Illinois
• November: US 218, Waverly to C57

• Unknown: US 61, Fort Madison to IA 16
• October: IA 163, Pella bypass
• November: US 63, Black Hawk/Bremer county line to IA 3 (Denver bypass 4 lanes by end of 1995)
• December: US 65, I-80 to IA 163
• New interchange: I-35/80, 86th Street (Urbandale); US 30, Dayton Avenue (Ames) (August)

• Unknown: US 151/IA 13, north junction to IA 100; US 218, IA 22 to G36; IA 28, Grand Avenue to IA 5; IA 163, west of Prairie City
• July: US 218, C57 to IA 57/58; IA 58, University Avenue to US 218
• New interchange: I-80, US 65 bypass (Altoona)

• Unknown: US 30, Marshalltown bypass; US 61, Blue Grass to I-280; IA 163, four-lane segments from Prairie City to Pella excluding bypasses
• August: US 61, Maquoketa to IA 136
• Fall: US 61, IA 136 to IA 956
• November: US 20, interchanges in Dubuque

• July: US 63, Eddyville to IA 149
• August: US 61, US 34 to IA 16
• September: IA 163, IA 92 to US 63
• October: US 218, G36 to IA 92 and G52 to G62
• November: US 151/IA 13, IA 100 to Mount Vernon Road; IA 141, US 169 to Granger; US 61, Dubuque Airport to Zwingle
• December: US 65, IA 163 to US 69; IA 5, US 65 duplex

• June: IA 163, G43 to IA 92
• August: US 63, IA 163 to Eddyville; US 218, IA 92 to G52
• September: IA 5, realignment around Des Moines Airport (bypassed Jan/01)
• Fall: IA 163, Prairie City bypass
• October: US 30, Nevada to US 65
• December: US 218, Waverly bypass

• Unknown: IA 5, US 65 to S23
• June: US 218, G62 to H28
• July: IA 163, bypasses of Monroe and Otley
• September: US 65, Bondurant to S27; IA 163, Pella to G43 (completes Des Moines-Oskaloosa)
• October: US 61, Zwingle to Maquoketa (completes Dubuque-Davenport)
• November: US 30/218, US 218 to IA 201
• December: US 18, I-35 to Rudd (with new I-35 interchange)

• May: US 151/IA 13, Mount Vernon Road to US 30; US 71, Milford to IA 9; US 34, New London bypass
• July: US 20, R77 to US 65; US 30, US 151 to near Mount Vernon
• August: US 18/218, Charles City bypass; IA 28, Army Post Road to north of Norwalk
• September: US 18, Rudd to Floyd; US 34, east of Mount Pleasant to northwest of Danville
• October: IA 5/92, near IA 181 [S45] to Knoxville; US 18/218, Floyd to north end of Charles City bypass; US 218, H28 to north end of Mount Pleasant bypass
• November: US 20, IA 14 to Grundy/Black Hawk county line; US 61, IA 38 to Y36

• January: IA 5, IA 28 to US 65/69
• May: US 61, Blue Grass bypass
• August: US 61, Fort Madison to US 218; US 151, Springville to near Linn/Jones county line
• November: US 151, IA 1 to north of IA 64; US 75, Sioux City bypass
• December: US 218/IA 27, Mount Pleasant bypass (part); US 34, 1.5 miles east of new 218

• July: US 61, Louisa/Muscatine county line to south end of Muscatine bypass; US 218/IA 27, Mount Pleasant bypass (rest)
• September: US 63, north junction US 18 to north end of New Hampton bypass; US 151, Cascade bypass; IA 5, I-35 to SW 96th Court (DM)
• October: US 18/63, north junction US 18 to south end of Business 63; IA 5, SW 96th Court to IA 28 (DM) (completes Des Moines beltway); IA 330, S62 to US 30
• November: US 218/IA 27, Plainfield bypass; US 18/63, south end of Business 63 to south of IA 346; IA 330, US 65/IA 117 to S62; US 65, S27 to IA 117/330
• December: IA 5, S23 to near Pleasantville

• July: US 20, US 65 to IA 14 (completes Fort Dodge-Waterloo)
• September: US 218/IA 27, Nashua bypass; IA 5, Pleasantville bypass
• October: IA 5/92, 1 mile east of S45 (completes Des Moines-Knoxville); US 151, Langworthy bypass
• November: US 218/IA 27, Nashua to Plainfield (completes north half of Avenue of the Saints)
• New interchange: I-35, Mills Civic Parkway (West Des Moines) (June 6)

• February: US 218/IA 27, Donnellson bypass
• May: US 151, near IA 64 to south end of Langworthy bypass
• June: US 151, north end of Monticello bypass to south end of Cascade bypass
• July: US 63, Eddyville bypass (completes DM/Oskaloosa-Ottumwa); US 151, Monticello bypass
• September: US 151, north end of Cascade bypass to Dubuque Airport (completes Cedar Rapids-Dubuque); IA 60, Alton bypass
• December: IA 27, bridge to Missouri

• May: US 34, Batavia bypass
• June: US 30, Le Grand bypass (was 2 lanes since Nov/04); US 218/IA 27, south end of Mount Pleasant bypass to IA 16
• July: US 20, west junction Business US 20 to US 169
• August: US 34, Mount Pleasant bypass and near IA 16 to V63; IA 27, US 218 to near bridge
• November: US 34, Danville to West Burlington; US 30, 5 miles in Tama County
• December: IA 60, Alton to Sioux/O'Brien county line

• May: US 218/IA 27, IA 16 to IA 2 (completes south half Avenue of the Saints)
• June: IA 60, 3 miles east of US 75 to Alton; IA 60, O'Brien/Osceola county line to south side of Sibley; US 34, small piece near Danville (completes Mount Pleasant-Burlington); US 34, east side of Fairfield to beginning of Mount Pleasant bypass
• October: IA 60, Sheldon bypass; US 34, future US 63 split to Batavia, including Agency bypass
• November: US 75, Le Mars bypass (completely finished June/07); IA 60, between Sheldon and Ashton bypasses
• New interchange: US 20, Ansborough Avenue (November 8)

• September: IA 60, IA 9 to 1 mile south of Minnesota line
• October: IA 60, rest of Sibley bypass
• November: US 63, Ottumwa bypass

• September: US 34, 3 miles in western Jefferson County
• October: IA 60, last segment into Minnesota with Bigelow bypass (completes four-lane IA 60)
• November: US 34, Fairfield bypass (completes Des Moines-Burlington)

• December: US 63, south of IA 346 to halfway between IA 188 and IA 93

• November: US 30, US 63 to east of Tama; US 30, US 65 to State Center
• December: US 20, IA 4 to Moorland/west junction Business 20

• July: US 30, State Center to IA 330
• August: US 30, Meskwaki (Mesquakie) casino to US 63 (realigned, two lanes Nov/10) (completes Ogden-Tama)
• November: US 61, Fort Madison bypass

• September: US 63, two segments in Bremer County between IA 3 and IA 188 (including IA 3 interchange)
• October: US 63, segment around C33 (completes Waterloo-New Hampton); US 218, realigned four-lane at new Janesville interchange
• New interchange: I-35, NE 36th Street (Ankeny) (November 20)

• Second year since 1957 that NO new four-lane segments opened in Iowa

• October: US 34, I-29 to Nebraska

• November: US 20, reconstructed segment through Correctionville

• December: IA 100, Edgewood Road to Covington Road
• New interchange: I-80, Alice's Road/Grand Prairie Parkway (WDM/Waukee) (December 1)

• November: US 20, Correctionville to L25
• December: US 61, 2 miles south of Grandview to Louisa County line

• September: US 20, L25 west to end of 1958 segment
• October: US 20, US 59 to US 71, and then Correctionville to US 59 (completes four-lane 20 in Iowa!)
• December: IA 100, Covington Road to US 30 (completes IA 100)
• New interchange: I-35/80, 100th Street (October 15/November 7); US 65/IA 330 (October 19)

• November: US 30, Mount Vernon-Lisbon bypass
• Complete reconfiguration of I-80/380 interchange begins
• New interchange: I-380, Forevergreen Road (North Liberty) (November 1)
• New interchange: IA 27/58, Viking Road (November 10)

• August: US 52, Southwest Arterial
• Late August/September: US 30, around and including new US 218 interchange
• November: I-74, westbound (northbound) bridge

• June: US 30, Tama to west of IA 21
• November: I-74, eastbound (southbound) bridge
• New interchange: US 20, Swiss Valley Road interchange (reconfigures curve) (December)

• November: US 30, section at IA 21 interchange but not interchange itself
• November: US 18/218, eastbound half of Floyd interchange

• June: US 61, north side Burlington to 210th Street
• August: US 30, through IA 21 exit
• New interchange: I-380, Tower Terrace Road (June)
• US 30, IA 21 to US 218
  

• none?

2025

• US 61, Mediapolis bypass
  
• US 218, controlled access conversion north of Janesville

2026

• US 61, Mediapolis to IA 78
  

2027

• none?

2028

• IA 27/58, Greenhill Road interchange
• US 151, Springville interchange
• US 61, IA 78 to IA 92

To Iowa Highway Ends Annex

To Iowa Highway Ends Index