State profile · Above median Poor share

Iowa bridge safety

Condition ratings, load ratings, and Poor-condition data for every public highway bridge in Iowa, based on the FHWA National Bridge Inventory.

20,753
Public bridges
36.5%
Good condition
20.0%
Poor condition

Data updated May 2026

Total Bridges

20,753

Public highway bridges in Iowa

Good Condition

36.5%

7,582 bridges rated 7-9

-13.5pp vs 50% benchmark

Poor Condition

20.0%

4,153 bridges whose lowest applicable component is rated 0-4

13.0pp vs national avg 7.0%

Iowa vs national bridge condition

Iowa - Good condition share 36.5%
National avg

Share of bridges rated 7-9 on the FHWA 0-9 scale (deck, superstructure, substructure all good).

Iowa - Poor-condition share 66.7%
National avg

Lower is better. Bar maxes at 30% (worst-state ceiling). National average sits at 7.0%.

Condition Distribution

Iowa38.5%40.4%21.1%GoodFairPoor
Bridge inventory deck-condition mix - Iowa (FHWA NBI)

Counties (99)

Adair 208 Adams 147 Allamakee 170 Appanoose 159 Audubon 161 Benton 327 Black Hawk 411 Boone 119 Bremer 220 Buchanan 281 Buena Vista 140 Butler 261 Calhoun 171 Carroll 223 Cass 237 Cedar 265 Cerro Gordo 210 Cherokee 223 Chickasaw 268 Clarke 150 Clay 138 Clayton 214 Clinton 325 Crawford 242 Dallas 154 Davis 156 Decatur 178 Delaware 254 Des Moines 156 Dickinson 73 Dubuque 304 Emmet 70 Fayette 288 Floyd 195 Franklin 214 Fremont 133 Greene 150 Grundy 270 Guthrie 236 Hamilton 134 Hancock 128 Hardin 211 Harrison 162 Henry 144 Howard 193 Humboldt 70 Ida 164 Iowa 189 Jackson 209 Jasper 321 Jefferson 142 Johnson 317 Jones 215 Keokuk 152 Kossuth 256 Lee 185 Linn 428 Louisa 134 Lucas 186 Lyon 241 Madison 221 Mahaska 219 Marion 204 Marshall 283 Mills 170 Mitchell 160 Monona 125 Monroe 126 Montgomery 184 Muscatine 127 O'Brien 229 Osceola 176 Page 185 Palo Alto 114 Plymouth 407 Pocahontas 186 Polk 415 Pottawattamie 469 Poweshiek 221 Ringgold 206 Sac 188 Scott 212 Shelby 194 Sioux 429 Story 262 Tama 307 Taylor 220 Union 153 Van Buren 142 Wapello 160 Warren 231 Washington 203 Wayne 163 Webster 179 Winnebago 48 Winneshiek 317 Woodbury 379 Worth 89 Wright 168

Iowa vs nearby ranks

Adjacent states by Poor-condition share (lower share = better)

States are ranked by the share of bridges whose lowest applicable component rating is 4 or below. This describes recorded condition; it does not measure funding effectiveness or live crossing safety. States here sit immediately above and below Iowa on the same metric.

WV

West Virginia

16.02% top marginal rate
Structure
Progressive
Burden @ $100K
$7,679

SD

South Dakota

16.24% top marginal rate
Structure
Progressive
Burden @ $100K
$5,905
Selected

IA

Iowa

20.01% top marginal rate
Structure
Progressive
Burden @ $100K
$20,753

VI

Virgin Islands

29.17% top marginal rate
Structure
Progressive
Burden @ $100K
$24

Bridges Needing Most Attention in Iowa

Six lowest-condition bridges in Iowa, ranked by the portal's composite display score. Inspection intervals are risk-based under current NBIS rules.

270TH STREET

Poor

Over: ROSE BRANCH

071343401, Adams, IA

Built 1976 Load: 2.7 t ADT: 79

LOCAL

Poor

Over: CREEK

078342601, Audubon, IA

Built 1935 Load: 2.7 t ADT: 21

KLINE RD

Poor

Over: MUD CREEK

87-12-15-02-10, Black Hawk, IA

Built 1948 Load: 2.7 t ADT: 11

LOCAL - 700TH

Poor

Over: TRIB TROUBLESOME CREEK

077351402, Cass, IA

Built 1983 Load: 2.7 t ADT: 11

LOCAL - DAYTONA

Poor

Over: BUCK CREEK

077361903, Cass, IA

Built 1980 Load: 2.7 t ADT: 35

100TH ST.

Poor

Over: UNION CREEK

083E20101, Clinton, IA

Built 1900 Load: 2.7 t ADT: 78

All Bridges in Iowa

LOCAL

Poor

Over: CREEK

094142401, Chickasaw, IA

Built 1975 Load: 28.5 t ADT: 47

LOCAL

Poor

Over: SMALL STREAM

095122902, Chickasaw, IA

Built 1975 Load: 28.5 t ADT: 82

LOCAL

Poor

Over: DEER CREEK

078311304, Guthrie, IA

Built 1947 Load: 28.5 t ADT: 150

FM

Poor

Over: LITTLE ASHER CR

084182202, Marshall, IA

Built 1968 Load: 28.5 t ADT: 432

FM

Poor

Over: SMALL STREAM

081152402, Poweshiek, IA

Built 1968 Load: 28.5 t ADT: 10

FM

Poor

Over: ROCK RIVER

096471603, Sioux, IA

Built 1952 Load: 28.5 t ADT: 1,017

FM

Poor

Over: RACCOON RIVER

091363601, Buena Vista, IA

Built 1976 Load: 28.6 t ADT: 1,228

FM

Poor

Over: DRY BRANCH

070022103, Des Moines, IA

Built 1970 Load: 28.6 t ADT: 240

FM

Poor

Over: FLOOD CREEK

096171906, Floyd, IA

Built 1975 Load: 28.6 t ADT: 491

BLUFF ROAD

Poor

Over: COOPER CREEK

068420708, Fremont, IA

Built 1959 Load: 28.6 t ADT: 244

1350 170TH ST

Poor

Over: WEST IOWA RIVER

095243101, Hancock, IA

Built 1979 Load: 28.6 t ADT: 569

FM

Poor

Over: SOLDIER RIVER

086403101, Ida, IA

Built 1971 Load: 28.6 t ADT: 350

FM

Poor

Over: LITTLE WHITEBREAST CREEK

072211509, Lucas, IA

Built 1974 Load: 28.6 t ADT: 490

FM

Poor

Over: INDIAN CREEK

080202901, Jasper, IA

Built 1951 Load: 28.7 t ADT: 150

W MAIN ST

Poor

Over: SMALL NATURAL STREAM

074222801, Warren, IA

Built 1959 Load: 28.7 t ADT: 643

VIKING AV

Poor

Over: BUCK CREEK

092113402, Bremer, IA

Built 1958 Load: 28.8 t ADT: 854

FM

Poor

Over: LITTLE BEAR CREEK

080110903, Iowa, IA

Built 1975 Load: 28.8 t ADT: 25

LOCAL ROAD

Poor

Over: RAT CREEK

098432801, Lyon, IA

Built 1900 Load: 28.8 t ADT: 21

LOCAL

Poor

Over: DRAINAGE

076290402, Madison, IA

Built 1952 Load: 28.8 t ADT: 15

FM

Poor

Over: INDIAN CREEK

073390901, Montgomery, IA

Built 1957 Load: 28.8 t ADT: 270

LOCAL

Poor

Over: MID FK GRAND RIVER

067302001, Ringgold, IA

Built 1988 Load: 28.8 t ADT: 45

LOCAL

Poor

Over: BIG CREEK

083252901, Boone, IA

Built 1915 Load: 29.0 t ADT: 50

FM

Poor

Over: CAIN CREEK

088340103, Calhoun, IA

Built 1971 Load: 29.0 t ADT: 110

FM

Poor

Over: KNOTTY CREEK

070032405, Des Moines, IA

Built 1980 Load: 29.0 t ADT: 1,000

FM

Poor

Over: TIPTON CR

087212202, Hardin, IA

Built 1974 Load: 29.0 t ADT: 687

LCL-ALLIS RD

Poor

Over: STREAM

073441304, Mills, IA

Built 1978 Load: 29.0 t ADT: 89

LOCAL

Poor

Over: STREAM

078161503, Poweshiek, IA

Built 1968 Load: 29.0 t ADT: 11

FM

Poor

Over: BUSHY CREEK

067351301, Taylor, IA

Built 1986 Load: 29.0 t ADT: 210

FM-MAGNOLIA RD

Poor

Over: MOSQUITO CREEK

076422103, Pottawattamie, IA

Built 1965 Load: 29.1 t ADT: 2,949

LOCAL

Poor

Over: CREEK

096082206, Winneshiek, IA

Built 1900 Load: 29.2 t ADT: 97

LOCAL

Poor

Over: STREAM

069170603, Appanoose, IA

Built 1900 Load: 29.3 t ADT: 11

FM

Poor

Over: DES MOINES RIVER

083262905, Boone, IA

Built 1972 Load: 29.3 t ADT: 769

LOCAL

Poor

Over: DRAINAGE DITCH

098260401, Winnebago, IA

Built 1985 Load: 29.3 t ADT: 26

150TH ST

Poor

Over: BROKEN KETTLE CREEK

093473501, Plymouth, IA

Built 1952 Load: 29.4 t ADT: 11

IRR-FM

Poor

Over: IOWA RIVER

083153007, Tama, IA

Built 1988 Load: 29.4 t ADT: 619

IA 23

Poor

Over: TRIBUTARY OF CEDAR CREEK

0.8 MI. N 0F Jct. SR T67, Mahaska, IA

Built 1928 Load: 29.5 t ADT: 2,350

LOCAL

Poor

Over: TWELVE MILE CREEK

073300701, Union, IA

Built 1979 Load: 29.5 t ADT: 62

FM

Poor

Over: ROCK CK

085120701, Benton, IA

Built 1958 Load: 29.6 t ADT: 30

FM 300TH ST

Poor

Over: BIG MUDDY CREEK

097362301, Clay, IA

Built 1963 Load: 29.7 t ADT: 369

FM SW NAPLES AV

Poor

Over: CROOKED CR

078063202, Johnson, IA

Built 1942 Load: 29.7 t ADT: 70

LOCAL

Poor

Over: SPRING CREEK

075150404, Mahaska, IA

Built 1948 Load: 29.7 t ADT: 71

LOCAL RD

Poor

Over: TIMBER CREEK

083182410, Marshall, IA

Built 1977 Load: 29.7 t ADT: 227

IA 141 & 175

Poor

Over: MAPLE RIVER

0.1 mi. E of W jct IA 175, Monona, IA

Built 1967 Load: 29.7 t ADT: 3,640

IA 10

Poor

Over: MUD CREEK

1.9 mi W of SR L48, O'Brien, IA

Built 1951 Load: 29.7 t ADT: 1,740

FM

Poor

Over: CEDAR RIVER

085091106, Benton, IA

Built 1969 Load: 29.8 t ADT: 1,267

FM

Poor

Over: LITTLE CEDAR RIVER

096151602, Floyd, IA

Built 1974 Load: 29.8 t ADT: 1,414

FM

Poor

Over: WAPSINONOC CREEK

078041407, Muscatine, IA

Built 1981 Load: 29.8 t ADT: 1,510

FM

Poor

Over: SMALL STREAM

077090708, Washington, IA

Built 1927 Load: 29.8 t ADT: 45

FM

Poor

Over: BR ENGLISH RIVER

077091703, Washington, IA

Built 1927 Load: 29.8 t ADT: 40

279TH AVE

Poor

Over: DRAINAGE

100091904, Winneshiek, IA

Built 1900 Load: 29.8 t ADT: 15

Showing 20,201-20,250 of 20,753 bridges

Related

All states → | National rankings → | Understanding conditions → | Retired SD term explained →
Data sourced from the FHWA National Bridge Inventory (NBI), latest released cycle. See our methodology for details. Retrieved and formatted by PlainBridges.

Disclaimer: This information is provided for informational purposes only and does not constitute professional advice. Data is sourced from the FHWA National Bridge Inventory (NBI). Poor condition is an inspection-record category, not a closure or unsafe-to-cross designation. Consult the bridge owner for current status.

Understanding Bridge Conditions

How FHWA rates bridge condition on a 0-9 scale.

Check Your Daily Bridges

How to look up bridge condition data for bridges on your route.

Read our methodology — how this data is sourced, computed, and verified.

Every figure on PlainBridge is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.