Beginning in 1979 and lasting through the early 1980s, a series of agreements between the Iowa Department of Transportation and individual county boards of supervisors led to a mass transfer of jurisdiction of several state highways in Iowa. County boards of supervisors were asked to convene functional classification boards in order to review the classification all of the highway miles within each respective county. Control of roads that were classified as trunk roads or trunk collector roads were transferred to the counties, while roads classified as arteries or arterial collectors were transferred to the state department of transportation. The vast majority of transfers took place in 1980.
| Iowa Primary Highway System | |
|---|---|
 Highways that changed jurisdiction around 1980 Removed highways Renumbered highways Added highways | |
| System information | |
| Notes | Primary highways in Iowa are generally state-maintained. |
| Highway names | |
| Interstates | Interstate X (I-X) |
| US Highways | U.S. Highway X (US X) |
| State | Highway X (IA X or Iowa X) |
| System links | |
Background
The 67th Iowa General Assembly passed a bill in 1978 that changed how the state department of transportation (DOT) classified highways and how they were funded throughout the state. The bill enacted an existing framework for county boards of supervisors to create reclassification boards that could appeal to a state board if certain changes to the road network were not satisfactory. The state's road use tax fund, which is the mechanism for allocating funds to the different levels of government for different levels of road, had both its inputs and outputs modified. The general fuel tax was raised from 7 to 8+1⁄2 cents per US gallon (1.8 to 2.2 ¢/L) for 1978 (equivalent to 33 to 40 cents per US gallon (8.7 to 10.6 ¢/L) in 2023), and to 10 ¢/US gal (2.6 ¢/L) for 1979 (equivalent to 42 ¢/US gal (11 ¢/L) in 2023).[1][2]
The state was attempting to offset the effects the 1970s energy crisis and the 1973–75 recession which strained state budgets by reducing income due to reduced demand for gasoline and increasing inflation.[3] The idea was for the DOT to save operational money by offloading minor highways to the respective counties. In 1979, Iowa had the 9th largest public road system in the United States with over 113,000 miles (182,000 km) of roadways, 10,000 miles (16,000 km) of which were primary highways, comprising Interstate Highways, U.S. Highways, and state highways. State planners sought to offload nearly one-third of the primary system. Naturally, county officials, whose road budgets were similarly strained, balked at the idea.[4]
The Iowa Code provided a manner for determining the class of a particular highway. Each county was to appoint a three-member board, one of whom was to be a state DOT employee, one a county engineer or supervisor, and the other a municipal leader chosen by a majority of mayors in the county. The board was to classify each mile of roads and streets in the county into one of twelve categories. Only three categories applied to primary highways–freeways and expressways, arterials, and arterial connectors. The freeway-expressway and arterial systems had limits on total mileage, 2,660 and 3,500 miles (4,280 and 5,630 km), respectively. The only other requirement of the reclassification boards was to ensure network continuity between counties.[5] Ultimately, these boards found about 1,000 miles (1,600 km) of minor highways that were on the primary system and 400 miles (640 km) of major highways on the secondary system.[4]
County officials were not keen on the idea of taking over more highway miles from the state when their own road budgets were tight. Clarke County officials sued the state classification board when it suggested the county take over an 11-mile (18 km) portion of U.S. Highway 69 (US 69). They felt the DOT was attempting to dump unwanted highway miles, which were also in poor condition, on a county unwilling to accept them.[3] Some counties felt pressure to accept roads from the state that the DOT had not maintained adequately.[6] Grundy County had some success by reclassifying some roads slated for transfer, such as Iowa Highway 214 (Iowa 214) into Wellsburg. That highway was reclassified as an arterial collector extension, keeping in spirit with an agreement it had with the DOT to maintain the highway until "Interstate 520" was built.[7] Other counties had appeals heard at the DOT headquarters in Ames.[8]
Construction of new highways, such as Interstate 380 (I-380) would cause a chain reaction in other state highways. It was predicted in 1979 that opening I-380 in the Cedar Rapids area would cause Iowa 150 to lose its status as a primary highway because the route ran roughly parallel to the planned Interstate Highway's corridor.[9] Indeed, when I-380 opened to traffic in 1984, Iowa 150 was rerouted away from Cedar Rapids over Iowa 101 to Vinton. One section of Iowa 150 along Collins Road in Cedar Rapids was still classified as an arterial connector; it became Iowa 100.
One provision in the Iowa Code required whichever agency maintained a section of highway previously to either repair the highway in question or to pay an appropriate amount of money equal to the costs of repairing the road to the agency receiving the road.[10] In Johnson County, state and county officials had difficulty reaching an agreement on a former segment of Iowa 1, by then renumbered Iowa 979. County officials wanted the state to take over County Road W66 (CR W66) from I-80 to the west overlook of Coralville Lake. The state countered with an offer to pay to upgrade Iowa 979 as well as have the county take over three other highways in the county.[11] The two sides were not any closer 18 months later when the DOT was ready to open a new four-lane US 218 south of Iowa City.[12] The routes for which no agreement could be made were ultimately kept by the DOT and assigned new route numbers, as was the case with Iowa 979.
Routes removed
Lengths represent the distances removed from the state highway system
| Number | Length (mi)[13] | Length (km) | Southern or western terminus | Northern or eastern terminus | Formed | Removed | Notes | |
|---|---|---|---|---|---|---|---|---|
 Iowa 27 | 6.86 | 11.04 | Alvord | US 75 near Rock Rapids | 1930 | 1980 | ||
 Iowa 42 | 4.18 | 6.73 | US 275 / Iowa 2 near Sidney | Riverton | 1920 | 1980 | ||
 Iowa 43 | 1.58 | 2.54 | Ringsted | Iowa 15 near Ringsted | 1920 | 1980 | ||
 Iowa 47 | 0.82 | 1.32 | Iowa 14 near Allison | Allison | 1951 | 1980 | ||
 Iowa 54 | 2.99 | 4.81 | Marble Rock | Iowa 14 east of Marble Rock | 1920 | 1980 | ||
 Iowa 77 | 7.80 | 12.55 | Iowa 78 at Richland | Iowa 92 at Keota | 1920 | 2003 | Segment into Keota remained | |
 Iowa 79 | 1.74 | 2.80 | Iowa 2 near Bonaparte | Bonaparte | 1920 | 1980 | ||
 Iowa 84 | 2.13 | 3.43 | The Eastern Iowa Airport | I-380 near Cedar Rapids | 1943 | 1980 | ||
 Iowa 86 | 0.47 | 0.76 | Fertile | Iowa 9 at Fertile | 1945 | 1980 | ||
 Iowa 87 | 4.06 | 6.53 | US 69 west of Elkhart | Elkhart | 1920 | 1983 | ||
 Iowa 88 | 8.01 | 12.89 | US 61 / Iowa 2 in Fort Madison | Iowa 16 in Denmark | 1940 | 1980 | ||
 Iowa 89 | 7.69 | 12.38 | Iowa 141 near Woodward | Iowa 17 in Madrid | 1946 | 1980 | Replaced by an extended Iowa 210 | |
 Iowa 90 | 16.32 | 26.26 | I-80 in Dallas County | I-35 in Des Moines | 1932 | 1981 | ||
 Iowa 91 | 4.18 | 6.73 | Ledyard | US 169 near Ledyard | 1940 | 1980 | ||
 Iowa 95 | 3.70 | 5.95 | Carbon | Iowa 148 north of Corning | 1932 | 1983 | ||
 Iowa 101 | 15.56 | 25.04 | US 218 in Vinton | Iowa 150 north of Urbana | 1920 | 1984 | Replaced by a relocated Iowa 150 | |
 Iowa 102 | 1.82 | 2.93 | Hawkeye | US 18 near Hawkeye | 1920 | 1980 | ||
 Iowa 104 | 1.53 | 2.46 | Woodburn | US 34 near Woodburn | 1927 | 1980 | ||
 Iowa 106 | 8.98 | 14.45 | Iowa 107 in Clear Lake | US 65 in Mason City | 1920 | 1980 | ||
 Iowa 108 | 1.18 | 1.90 | Delta | Iowa 92 near Delta | 1923 | 1980 | ||
 Iowa 112 | 5.19 | 8.35 | Volga | Iowa 13 near Osborne | 1931 | 1980 | ||
 Iowa 114 | 9.20 | 14.81 | Iowa 92 near West Chester | Iowa 22 at Wellman | 1969 | 1981 | Previously Iowa 81 | |
 Iowa 119 | 1.04 | 1.67 | Dorchester | Iowa 76 near Dorchester | 1923 | 1980 | ||
 Iowa 120 | 0.80 | 1.29 | Stanton | US 34 near Stanton | 1924 | 1980 | ||
 Iowa 123 | 0.45 | 0.72 | US 34 near Rome | Rome | 1970 | 1980 | ||
 Iowa 125 | 3.26 | 5.25 | Salem | US 218 near Salem | 1924 | 1981 | ||
 Iowa 126 | 0.97 | 1.56 | US 6 near Mitchellville | Mitchellville | 1924 | 1980 | ||
 Iowa 134 | 4.06 | 6.53 | US 65 near Hampton | Geneva | 1935 | 1980 | ||
 Iowa 135 | 1.96 | 3.15 | Montour | US 30 near Montour | 1954 | 1980 | ||
 Iowa 152 | 1.31 | 2.11 | US 34 near Murray | Murray | 1926 | 1980 | ||
 Iowa 155 | 3.05 | 4.91 | Nodaway | US 34 near Nodaway | 1933 | 1980 | ||
 Iowa 156 | 0.33 | 0.53 | Bussey city limits | Bussey | — | 2003 | Turned over within city limits | |
 Iowa 159 | 1.83 | 2.95 | Iowa 92 near Harper | Harper | 1929 | 1980 | ||
 Iowa 166 | 0.57 | 0.92 | Hastings | US 34 near Hastings | 1930 | 1980 | ||
 Iowa 167 | 3.21 | 5.17 | Doon | US 75 near Doon | 1930 | 1980 | ||
 Iowa 168 | 2.70 | 4.35 | Iowa 83 near Minden | Shelby | 1930 | 1980 | ||
 Iowa 171 | 1.05 | 1.69 | Elberon | Iowa 21 near Elberon | 1935 | 1980 | ||
 Iowa 172 | 4.23 | 6.81 | Elgin | US 18 in Clermont | 1930 | 1980 | ||
 Iowa 177 | 3.20 | 5.15 | Iowa 9 near Osage | Elgin | 1937 | 1980 | ||
 Iowa 178 | 0.98 | 1.58 | Iowa 9 near Little Rock | Little Rock | 1930 | 1980 | ||
 Iowa 179 | 0.76 | 1.22 | US 69 near Klemme | Klemme | 1930 | 1980 | ||
 Iowa 180 | 2.46 | 3.96 | Hayesville | Iowa 149 near Hayesville | 1930 | 1980 | ||
 Iowa 186 | 3.27 | 5.26 | US 34 near Prescott | Prescott | 1930 | 1980 | ||
 Iowa 189 | 1.00 | 1.61 | Bridgewater | Iowa 92 north or Bridgwater | 1930 | 1980 | ||
 Iowa 190 | 7.46 | 12.01 | Fairbank | Iowa 150 near Oelwein | 1931 | 1980 | Replaced by Iowa 281 | |
 Iowa 198 | 0.43 | 0.69 | Garrison | Garrison city limits | — | 2003 | Turned over within city limits | |
 Iowa 199 | 0.54 | 0.87 | Van Horne city limits | Van Horne | — | 2003 | Turned over within city limits | |
 Iowa 200 | 0.59 | 0.95 | Keystone city limits | Keystone | — | 2003 | Turned over within city limits | |
 Iowa 203 | 8.78 | 14.13 | Terril | Iowa 9 near Superior | 1920 | 1980 | ||
 Iowa 213 | 3.72 | 5.99 | Blakesburg | US 34 north or Blakesburg | 1931 | 1980 | ||
 Iowa 216 | 1.70 | 2.74 | Iowa 5 | Exline | 1931 | 1981 | ||
 Iowa 219 | 1.53 | 2.46 | Iowa 9 near Lake Park | Lake Park | 1931 | 1980 | ||
 Iowa 221 | 2.44 | 3.93 | US 69 near Story City | I-35 near Story City | — | 2003 | Segment from I-35 to Roland remained | |
 Iowa 222 | 14.72 | 23.69 | Iowa 15 near Ottosen | Livermore | 1931 | 1980 | ||
 Iowa 226 | 10.78 | 17.35 | US 18 near Wesley | Titonka | 1931 | 1980 | ||
 Iowa 231 | 1.83 | 2.95 | Iowa 10 near Ireton | Ireton | 1931 | 1981 | ||
 Iowa 232 | 1.99 | 3.20 | Earlham | I-80 near Earlham | 1931 | 1980 | ||
 Iowa 237 | 1.23 | 1.98 | Ocheyedan | Iowa 9 near Ocheyedan | 1931 | 1981 | ||
 Iowa 241 | 0.99 | 1.59 | Readlyn | Iowa 3 near Readlyn | 1931 | 1980 | ||
 Iowa 243 | 7.97 | 12.83 | Iowa 140 near Kingsley | Pierson | 1931 | 1980 | ||
 Iowa 244 | 1.96 | 3.15 | Henderson | US 59 | 1931 | 1980 | ||
 Iowa 246 | 3.26 | 5.25 | US 61 in Zwingle | La Motte | 1931 | 1980 | ||
 Iowa 248 | 0.49 | 0.79 | Independence State Hospital | US 20 in Independence | 1931 | 1980 | ||
 Iowa 250 | 0.59 | 0.95 | Lakota | US 169 / Iowa 9 near Lakota | 1932 | 1980 | ||
 Iowa 251 | 1.71 | 2.75 | St. Charles | I-35 near St. Charles | 1932 | 1980 | ||
 Iowa 254 | 7.91 | 12.73 | Iowa 9 near Buffalo Center | MN 254 near Rake | 1969 | 1980 | ||
 Iowa 255 | 2.26 | 3.64 | Orchard | US 218 near Orchard | 1932 | 1980 | ||
 Iowa 256 | 0.80 | 1.29 | Iowa 17 near Corwith | Corwith | 1932 | 1980 | ||
 Iowa 259 | 0.45 | 0.72 | Tingley city limits | Tingley | — | 2003 | Turned over within city limits | |
 Iowa 262 | 1.99 | 3.20 | US 69 near Galt | Galt | 1933 | 1980 | ||
 Iowa 263 | 2.02 | 3.25 | Coulter | Latimer | 1933 | 1980 | Double spur route with Iowa 3 | |
 Iowa 264 | 2.39 | 3.85 | Linn Grove | Iowa 10 near Linn Grove | 1933 | 1980 | ||
 Iowa 266 | 0.12 | 0.19 | Weldon city limits | Weldon | — | 2003 | Turned over within city limits | |
 Iowa 267 | 1.19 | 1.92 | Iowa 93 near Randalia | Randalia | 1934 | 1980 | ||
 Iowa 269 | 3.01 | 4.84 | Iowa 16 near Stockport | Stockport | 1934 | 1980 | ||
 Iowa 270 | 1.80 | 2.90 | Iowa 16 near Hillsboro | Hillsboro | 1934 | 1980 | ||
 Iowa 271 | 0.84 | 1.35 | Iowa 4 near Yale | Yale | 1935 | 1980 | ||
 Iowa 277 | 6.24 | 10.04 | Numa | Iowa 5 near Centerville | 1935 | 1980 | ||
 Iowa 278 | 2.05 | 3.30 | Rathbun | Iowa 5 near Rathbun | 1935 | 1980 | ||
 Iowa 279 | 0.72 | 1.16 | Atkins city limits | Atkins | — | 2003 | Turned over within city limits | |
 Iowa 284 | 5.58 | 8.98 | Aurora | Iowa 187 at Lamont | 1935 | 1980 | ||
 Iowa 287 | 0.42 | 0.68 | Newhall city limits | Newhall | — | 2003 | Turned over within city limits | |
 Iowa 288 | 4.58 | 7.37 | US 65 near Manly | Plymouth | 1935 | 1980 | ||
 Iowa 289 | 6.14 | 9.88 | Alta Vista | US 63 near Lourdes | 1935 | 1980 | ||
 Iowa 290 | 1.99 | 3.20 | Farmersburg | Iowa 13 near Farmersburg | 1935 | 1980 | ||
 Iowa 291 | 1.01 | 1.63 | Low Moor | US 30 near Low Moor | 1935 | 1979 | ||
 Iowa 292 | 3.17 | 5.10 | Linden | Iowa 44 | 1935 | 1980 | ||
 Iowa 293 | 1.42 | 2.29 | Iowa 90 near Van Meter | Van Meter | 1935 | 1980 | ||
 Iowa 295 | 5.09 | 8.19 | Westgate | Iowa 150 near Maynard | 1935 | 1980 | ||
 Iowa 296 | 4.44 | 7.15 | CR C24 near Wadena | Iowa 56 near Wadena | 1935 | 1980 | ||
 Iowa 302 | 3.00 | 4.83 | Thor | Iowa 3 near Thor | 1935 | 1980 | ||
 Iowa 303 | 3.51 | 5.65 | US 34 near Fairfield | Libertyville | 1935 | 1981 | ||
 Iowa 304 | 1.59 | 2.56 | Iowa 78 near Ollie | Ollie | 1935 | 1980 | ||
 Iowa 309 | 2.32 | 3.73 | Beacon | Iowa 137 in Oskaloosa | 1935 | 1980 | ||
 Iowa 311 | 0.55 | 0.89 | Liscomb | Liscomb city limits | 1935 | 1989 | Turned over within city limits | |
 Iowa 312 | 5.70 | 9.17 | Iowa 9 near Riceville | McIntire | 1935 | 1980 | ||
 Iowa 313 | 2.03 | 3.27 | Melvin city limits | Melvin | 1935 | 2002 | ||
 Iowa 317 | 0.81 | 1.30 | US 65 near Zearing | Zearing | 1935 | 1980 | ||
 Iowa 318 | 5.51 | 8.87 | Clutier | Iowa 21 near Clutier | 1935 | 1980 | ||
 Iowa 319 | 0.50 | 0.80 | Gravity | Iowa 148 at Gravity | 1935 | 1980 | ||
 Iowa 323 | 3.74 | 6.02 | Iowa 17 near Woolstock | Woolstock | 1935 | 1980 | ||
 Iowa 325 | 0.47 | 0.76 | Spillville | Spillville city limits | 1935 | 2003 | Turned over within city limits | |
 Iowa 326 | 2.18 | 3.51 | Bristow | Iowa 3 near Bristow | 1935 | 1981 | ||
 Iowa 328 | 2.29 | 3.69 | US 20 near Galva | Galva | 1935 | 1980 | ||
 Iowa 329 | 4.85 | 7.81 | US 169 at Boxholm | Pilot Mound | 1935 | 1980 | ||
 Iowa 332 | 1.00 | 1.61 | Pilot Knob State Park | Iowa 9 near Forest City | 1935 | 1980 | Park access road | |
 Iowa 334 | 1.87 | 3.01 | US 63 near Frederika | Frederika | 1935 | 1980 | ||
 Iowa 335 | 0.64 | 1.03 | Iowa 141 near Dawson | Dawson | 1935 | 1980 | ||
 Iowa 336 | 2.48 | 3.99 | Iowa 150 near Rowley | Rowley | 1936 | 1980 | ||
 Iowa 337 | 3.36 | 5.41 | Iowa 9 near Grafton | Grafton | 1936 | 1980 | ||
 Iowa 342 | 0.95 | 1.53 | Iowa 141 near Jamaica | Jamaica | 1936 | 1980 | ||
 Iowa 343 | 1.01 | 1.63 | Iowa 333 near Northboro | Northboro | 1937 | 1980 | ||
 Iowa 351 | 0.86 | 1.38 | Rembrandt | US 71 near Rembrandt | 1938 | 1981 | ||
 Iowa 352 | 0.75 | 1.21 | US 71 near Truesdale | Truesdale | 1938 | 1981 | ||
 Iowa 353 | 0.35 | 0.56 | Rowan | Iowa 3 at Rowan | 1938 | 1980 | ||
 Iowa 356 | 6.37 | 10.25 | Packwood | Iowa 1 near Packwood | 1938 | 1981 | ||
 Iowa 358 | 1.55 | 2.49 | Whittemore | US 18 / Iowa 15 near Whittemore | 1938 | 1980 | ||
 Iowa 362 | 1.17 | 1.88 | Macedonia | US 59 near Macedonia | 1938 | 1980 | ||
 Iowa 364 | 0.74 | 1.19 | Cota Creek | Harpers Ferry | 1938 | 2003 | Turned over within city limits | |
 Iowa 365 | 1.07 | 1.72 | Tracy | Iowa 92 near Tracy | 1939 | 1980 | ||
 Iowa 367 | 3.39 | 5.46 | Rutland | US 169 near Humboldt | 1942 | 1980 | ||
 Iowa 369 | 5.54 | 8.92 | Iowa 2 near Moulton | Unionville | 1942 | 1980 | ||
 Iowa 374 | 7.99 | 12.86 | US 71 near Sioux Rapids | Webb | 1942 | 1980 | ||
 Iowa 377 | 0.51 | 0.82 | Harbor Drive in Sioux City | Iowa 970 in Sergeant Bluff | 1942 | 1980 | Airport access road | |
 Iowa 379 | 4.59 | 7.39 | Joice | Iowa 105 near Lake Mills | 1942 | 1980 | ||
 Iowa 381 | 0.67 | 1.08 | Iowa 254 near Rake | Rake | 1954 | 1980 | ||
 Iowa 387 | 0.52 | 0.84 | Davenport Municipal Airport | US 61 3 miles north of Davenport | 1951 | 1979 | ||
 Iowa 388 | 0.35 | 0.56 | Calumet | US 59 at Calumet | 1946 | 1980 | ||
 Iowa 390 | 0.74 | 1.19 | Iowa 10 near Marathon | Marathon | 1946 | 1980 | ||
 Iowa 393 | 2.40 | 3.86 | Ionia | US 18 near Ionia | 1948 | 1980 | ||
 Iowa 394 | 1.72 | 2.77 | Iowa 2 near Denmark | Iowa Army Ammunition Plant southern entrance | 1948 | 1980 | ||
 Iowa 395 | 0.53 | 0.85 | Melbourne | Iowa 330 near Melbourne | 1948 | 1983 | ||
 Iowa 396 | 0.52 | 0.84 | Iowa 175 near Farnhamville | Farnhamville | 1954 | 1980 | ||
 Iowa 398 | 1.24 | 2.00 | Brooklyn | US 6 near Brooklyn | 1956 | 1980 | ||
 Iowa 400 | 4.54 | 7.31 | Truro | I-35 near Truro | 1958 | 1980 | ||
 Iowa 403 | 0.70 | 1.13 | Cushing | US 20 near Cushing | 1958 | 1980 | ||
 Iowa 405 | 0.24 | 0.39 | Lone Tree | Lone Tree city limits | 1958 | 2003 | Turned over within city limits | |
 Iowa 408 | 7.40 | 11.91 | US 169 near Lu Verne | Lu Verne | 1957 | 1980 | ||
 Iowa 412 | 4.72 | 7.60 | US 63 in Waterloo | US 218 in Waterloo | 1960 | 1983 | San Marnan Drive in Waterloo | |
 Iowa 413 | 3.95 | 6.36 | US 20 in Fort Dodge | Fort Dodge Municipal Airport | 1960 | 1980 | ||
 Iowa 424 | 0.44 | 0.71 | Britt city limits | US 18 near Britt | 1961 | 1980 | ||
 Iowa 426 | 0.52 | 0.84 | Iowa 92 near Rose Hill | Rose Hill | 1960 | 1980 | ||
 Iowa 428 | 1.21 | 1.95 | Anamosa | US 151 / Iowa 64 at Anamosa | 1965 | 1980 | ||
 Iowa 924 | 4.00 | 6.44 | Webster–Greene County Line | Iowa 175 near Farnhamville | 1980 | 1982 | ||
 Iowa 933 | 0.74 | 1.19 | Iowa 141 in Perry | Iowa 141 in Perry | 1976 | 1984 | Former section of Iowa 141 | |
 Iowa 934 | 1.07 | 1.72 | US 61 near Burlington | US 61 near Burlington | 1976 | 1980 | Former section of US 61; now Memorial Park Road | |
 Iowa 935 | 0.77 | 1.24 | — | — | 1976 | 1981 | Former section of US 34 parallel to Business US 34 in Burlington | |
 Iowa 938 | 1.57 | 2.53 | Iowa 947 near Manchester | Manchester Fish Hatchery | 1976 | 1980 | Former Iowa 116 | |
 Iowa 939 | 6.76 | 10.88 | US 65 | Iowa 2 near Corydon | 1976 | 1980 | Former section of Iowa 2 | |
 Iowa 940 | 2.51 | 4.04 | — | — | 1976 | 1980 | Former sections of Iowa 2 | |
 Iowa 941 | 2.99 | 4.81 | County Road J18 in Moravia | Iowa 5 near Moravia | 1976 | 1980 | Former section of Iowa 5 | |
 Iowa 942 | 5.70 | 9.17 | Iowa 5 near Moravia | County Road J18 in Moravia | 1976 | 1980 | Former sections of Iowa 5 | |
 Iowa 943 | 0.69 | 1.11 | — | — | 1974 | 1980 | Former section of Iowa 13 in Central City | |
 Iowa 944 | 0.99 | 1.59 | Iowa 13 in Manchester | Iowa 13 in Manchester | 1976 | 1980 | Former section of Iowa 13 | |
 Iowa 946 | 2.72 | 4.38 | Luana city limits | US 18 / US 52 in Monona | 1976 | 1980 | Former section of US 18 / US 52 concurrency; two sections | |
 Iowa 947 | 23.75 | 38.22 | Iowa 187 | Dyersville city limits | 1976 | 1981 | Former section of US 20 | |
 Iowa 951 | 2.65 | 4.26 | US 34 west of Osceola | US 34 near Osceola | 1976 | 1980 | Former section of US 34 | |
 Iowa 952 | 0.18 | 0.29 | — | — | 1978 | 1982 | Former section of US 67 north of Clinton | |
 Iowa 953 | 0.89 | 1.43 | Iowa 38 near Muscatine | Iowa 38 in Muscatine | 1976 | 1980 | Former section of Iowa 38 | |
 Iowa 959 | 1.27 | 2.04 | US 65 / US 69 in Des Moines | Des Moines city limits | 1970 | 1981 | Former section of US 65 / US 69 concurrency | |
 Iowa 960 | 1.58 | 2.54 | Clarinda city limits | Iowa 2 near Clarinda | 1973 | 1982 | Former section of Iowa 2 | |
 Iowa 961 | 0.56 | 0.90 | Villisca city limits | US 71 near Villisca | 1976 | 1980 | Former section of US 71 | |
 Iowa 965 | 3.29 | 5.29 | — | — | 1976 | 1980 | Former section of US 52 | |
 Iowa 969 | 0.52 | 0.84 | US 169 near Burt | Burt | 1976 | 1980 | former Iowa 422 | |
 Iowa 971 | 10.78 | 17.35 | Iowa 2 | US 59 in Shenandoah | 1975 | 1979 | Former section of Iowa 2 | |
 Iowa 972 | 10.17 | 16.37 | Iowa 92 / US 169 in Winterset | US 169 | 1974 | 1980 | Former section of US 169 | |
 Iowa 973 | 1.49 | 2.40 | Iowa 92 in Winterset | Iowa 972 in Winterset | 1976 | 1980 | Former section of Iowa 92 | |
 Iowa 976 | 2.00 | 3.22 | US 218 | Mount Pleasant city limits | 1974 | 1980 | Former section of US 218; formerly Iowa 972 | |
 Iowa 980 | 0.77 | 1.24 | US 34 near Ottumwa | Ottumwa city limits | 1967 | 1980 | Former section of US 34; formerly US 34 Alternate | |
 Iowa 981 | 0.44 | 0.71 | Iowa 150 near Fayette | Fayette city limits | 1967 | 1980 | Former section of Iowa 150; formerly Iowa 991 | |
 Iowa 983 | 0.81 | 1.30 | US 34 west of Chariton | US 34 east of Chariton | 1967 | 1980 | Former section of US 34; formerly Iowa 995 and Iowa 996 | |
 Iowa 984 | 2.24 | 3.60 | Bettendorf city limits | US 67 in Le Claire | 1968 | 1982 | Former section of Iowa 417 | |
 Iowa 999 | 2.22 | 3.57 | Spruce Street in College Springs | Iowa 333 near College Springs | 1961 | 1980 | Former section of Iowa 333 | |
| ||||||||
Routes added
| Number | Length (mi)[14] | Length (km) | Southern or western terminus | Northern or eastern terminus | Formed | Removed | Notes | |
|---|---|---|---|---|---|---|---|---|
| Iowa 79 | 5.64 | 9.08 | Geode State Park | US 34 in Middletown | 1980 | 2003 | ||
| Iowa 91 | 4.64 | 7.47 | Iowa 9 in Lyon County | MN 91 at the Minnesota state line | 1980 | 2003 | ||
 Iowa 100 | 2.74[15] | 4.41 | I-380 in Cedar Rapids | US 151 in Cedar Rapids | 1984 | current | ||
 Iowa 102 | 15.96 | 25.69 | Iowa 163 in Pella | US 63 / Iowa 146 in New Sharon | 1980 | current | ||
 Iowa 115 | 1.24 | 2.00 | US 34 near Stanton | Viking Lake State Park | 1980 | 2003 | ||
 Iowa 134 | 1.75 | 2.82 | Beed's Lake State Park | Iowa 3 near Hampton | 1980 | 1987 | ||
 Iowa 142 | 20.96 | 33.73 | Iowa 2 in Plano | Iowa 5 near Moravia | 1980 | 2003 | ||
 Iowa 152 | 1.34 | 2.16 | I-35 near Osceola | US 69 at Osceola | 1980 | 2014 | ||
 Iowa 186 | 3.38 | 5.44 | Green Valley State Park | Iowa 25 in Creston | 1980 | 2001 | ||
 Iowa 192 | 4.74 | 7.63 | I-29 / I-80 at Council Bluffs | I-29 at Council Bluffs | 1931 | 2017 | Was decommissioned in 1975, but restored in 1980 | |
 Iowa 243 | 0.56 | 0.90 | Black Hawk Lake State Park | US 71 / Iowa 175 near Wall Lake | 1980 | 2003 | ||
 Iowa 244 | 0.68 | 1.09 | I-80 near Neola | Iowa 191 in Neola | 1980 | 2003 | ||
 Iowa 362 | 5.09 | 8.19 | Wilson State Park | I-29 at Loveland | 1980 | 2003 | ||
 Iowa 394 | 10.67 | 17.17 | Route B at St. Francisville, Mo. | US 218 near Donnellson | 1980 | 2005 | Replaced by Iowa 27 | |
 Iowa 403 | 0.47 | 0.76 | SD 48 near Akron | Iowa 12 in Akron | 1980 | 2003 | ||
 Iowa 428 | 5.75 | 9.25 | Maquoketa Caves State Park | US 61 near Maquoketa | 1980 | 2003 | ||
 Iowa 918 | 1.12[15] | 1.80 | Iowa 16 near Eldon | Iowa 16 in Eldon | 1984 | 2003 | Former section of Iowa 16 | |
 Iowa 919 | 0.29[15] | 0.47 | Iowa 363 in Urbana | Walnut Street in Urbana | 1984 | 1995 | Former section of Iowa 363 | |
 Iowa 920 | 12.61[15] | 20.29 | Center Point | Iowa 150 near Urbana | 1984 | 2003 | Former section of Iowa 150 | |
 Iowa 921 | 12.47[15] | 20.07 | Iowa 920 in Center Point | Hiawatha | 1984 | 1985 | Former section of Iowa 150 | |
 Iowa 922 | 1.27[15] | 2.04 | US 61 in Muscatine | Iowa 22 in Muscatine | 1984 | 1986 | Former section of US 61; became part of an extended Iowa 38 | |
 Iowa 923 | 4.52[16] | 7.27 | — | — | 1982 | 2003 | Former section of US 218; had three sections | |
 Iowa 925 | 24.32 | 39.14 | I-80 / US 6 in Adair | US 6 near Dexter | 1980 | 2003 | Former section of US 6 | |
 Iowa 926 | 6.63 | 10.67 | US 6 in Altoona | US 6 / Iowa 14 in Newton | 1980 | 1988 | Former section of US 6 | |
 Iowa 927 | 19.02 | 30.61 | US 6 / Iowa 38 in Wilton | I-280 / US 6 near Davenport | 1980 | 2003 | Former section of US 6 | |
 Iowa 928 | 17.15 | 27.60 | Iowa 17 near Webster City | CR D20 near Williams | 1980 | 2003 | Former section of US 20 | |
 Iowa 929 | 0.79 | 1.27 | Murray city limits | Maple Street in Murray | 1980 | 2003 | Former section of Iowa 152 | |
 Iowa 931 | 8.47 | 13.63 | I-35 in Ankeny | US 65 in Polk County | 1980 | 2003 | ||
 Iowa 935 | 1.38[16] | 2.22 | I-29 | Mills–Pottawattamie county line | 1982 | 2003 | Former section of Iowa 370 | |
 Iowa 938 | 0.46 | 0.74 | Unionville | Unionville city limits | 1980 | 2003 | Former section of Iowa 369 | |
 Iowa 939 | 12.37 | 19.91 | Independence | Iowa 187 near Masonville | 1980 | 2003 | Former section of US 20 | |
 Iowa 942 | 0.47 | 0.76 | Woodburn | Woodburn city limits | 1980 | 2003 | Former section of Iowa 104 | |
 Iowa 943 | 0.43 | 0.69 | Galva | Galva city limits | 1980 | 1987 | Former section of Iowa 328 | |
 Iowa 944 | 0.56 | 0.90 | US 61 / Iowa 2 in Fort Madison | Fort Madison city limits | 1980 | 2003 | Former section of Iowa 88 | |
 Iowa 945 | 4.61 | 7.42 | I-80 near Altoona | Iowa 931 in Polk County | 1980 | 2003 | ||
 Iowa 950 | 3.35 | 5.39 | US 6 / US 65 in Altoona | Iowa 163 in Pleasant Hill | 1980 | 1994 | Now 34th Avenue/56th Street | |
 Iowa 951 | 3.15[15] | 5.07 | Carbon city limits | Iowa 148 | 1983 | 1993 | Former section of Iowa 95 | |
 Iowa 960 | 1.11[16] | 1.79 | — | — | 1982 | 1986 | Former section of US 61 | |
 Iowa 985 | 1.95 | 3.14 | US 52 near Bellevue State Park | US 52 near Bellevue | 1980 | 2003 | ||
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Existing route changes
| Number | Change in length | Southern or western terminus | Northern or eastern terminus | Formed | Removed | Notes | ||
|---|---|---|---|---|---|---|---|---|
| mi[a] | km | |||||||
 Iowa 21 | 12.42 | 19.99 | Iowa 149 near Hedrick | Iowa 92 near Delta | 1934 | current | Extended south from Iowa 92 | |
 Iowa 25 | -6.99 | −11.25 | Blockton | Iowa 2 near Benton | 1926 | current | Continued south to Blockton | |
 Iowa 28 | 6.18 | 9.95 | Iowa 5 in Des Moines | US 6 in Des Moines | 1926 | current | Extended north from Iowa 5 | |
 Iowa 72 | 3.16 | 5.09 | Dows | I-35 east of Dows | 1920 | 1986 | Extended east from Dows | |
 Iowa 139 | -12.25 | −19.71 | Protivin | Iowa 9 at Cresco | 1930 | current | Spur route to Protivin removed | |
 Iowa 140 | 15.55 | 25.03 | Kingsley | Iowa 3 at Remsen | 1926 | current | Extended north from Kingsley | |
 Iowa 145 | 3.13 | 5.04 | I-29 near Thurman | Thurman | 1931 | 2003 | Extended west from Thurman | |
 Iowa 150 | -11.05[b] | −17.78 | US 151 in Cedar Rapids US 218 at Vinton | Iowa 101 in Benton County Iowa 920 in Benton County | 1941 | current | Rerouted over Iowa 101 in 1984 | |
 Iowa 160 | 1.24 | 2.00 | US 69 at Ankeny | I-35 at Ankeny | 1947 | current | Extended east within Ankeny | |
 Iowa 173 | 11.53 | 18.56 | Iowa 83 near Atlantic | Elk Horn | 1930 | current | Extended south from Elk Horn | |
 Iowa 210 | 19.58 | 31.51 | Iowa 141 near Woodward | Slater | 1931 | current | Rerouted over Iowa 89 | |
 Iowa 212 | -10.02 | −16.13 | Iowa 21 near Belle Plaine | US 30 near Chelsea | 1934 | current | Continued northwest to US 30 until 1980 | |
 Iowa 220 | -2.20[c] | −3.54 | Upper South Amana Iowa 149 at Amana | US 6 / Iowa 149 at South Amana East Amana | 1931 | current | Continued east to East Amana and south to Upper South Amana until 1980 | |
 Iowa 223 | 6.94 | 11.17 | Iowa 330 near Baxter | Baxter | 1931 | 1997 | Extended west from Baxter | |
 Iowa 224 | 9.37 | 15.08 | Kellogg | Iowa 14 near Laurel | 1931 | current | Extended north from Kellogg in 1980 | |
 Iowa 281 | 17.29 | 27.83 | Dunkerton | Iowa 150 at Oelwein | 1935 | current | Rerouted over Iowa 190 | |
 Iowa 333 | -3.77 | −6.07 | Fremont–Page county line near Northboro I-29 at Hamburg | US 71 near Braddyville US 59 near Northboro | 1935 | current | Route swap | |
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