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: TEN MILE CREEK

098090806, Winneshiek, IA

Built 1900 Load: 21.2 t ADT: 118

FM - 710TH

Poor

Over: WATERWAY

076352504, Cass, IA

Built 1958 Load: 21.3 t ADT: 20

LOCAL - 730TH

Poor

Over: WATERWAY

077343204, Cass, IA

Built 1958 Load: 21.3 t ADT: 30

240TH ST

Poor

Over: BR GOWER CR

080041801, Cedar, IA

Built 1924 Load: 21.3 t ADT: 50

LOCAL 540TH ST

Poor

Over: WEST FORK LITTLE SIOUX

091420301, Cherokee, IA

Built 1925 Load: 21.3 t ADT: 20

LOCAL-G AVE.

Poor

Over: SMALL CREEK

092413102, Cherokee, IA

Built 1924 Load: 21.3 t ADT: 50

FM

Poor

Over: FROST CREEK

080332602, Guthrie, IA

Built 1959 Load: 21.3 t ADT: 15

TIMBER AVE

Poor

Over: TURKEY RIVER

097110502, Howard, IA

Built 1987 Load: 21.3 t ADT: 48

LOC 100TH AVE

Poor

Over: D.D.#60

100291002, Kossuth, IA

Built 1984 Load: 21.3 t ADT: 21

LOCAL

Poor

Over: SMALL STREAM

073041401, Louisa, IA

Built 1943 Load: 21.3 t ADT: 47

LOCAL

Poor

Over: BRUSH CREEK

079163103, Poweshiek, IA

Built 1958 Load: 21.3 t ADT: 34

FM

Poor

Over: EAST CREEK

067282501, Ringgold, IA

Built 1958 Load: 21.3 t ADT: 11

LOCAL

Poor

Over: BRANCH OF IOWA RIVER

082143202, Tama, IA

Built 1950 Load: 21.3 t ADT: 5

LOCAL

Poor

Over: EAST BRANCH SALT CREEK

084131201, Tama, IA

Built 1936 Load: 21.3 t ADT: 39

270TH ST

Poor

Over: CRANE CREEK

091123301, Bremer, IA

Built 1900 Load: 21.4 t ADT: 20

LOCAL

Poor

Over: LAKE CREEK

089323501, Calhoun, IA

Built 1917 Load: 21.4 t ADT: 20

LOCAL- U AVE

Poor

Over: PITCHER CR

090390902, Cherokee, IA

Built 1926 Load: 21.4 t ADT: 15

FM

Poor

Over: SMALL STREAM

089E12004, Dubuque, IA

Built 1984 Load: 21.4 t ADT: 412

LOC 150TH AVE

Poor

Over: PURCELL CREEK

095280902, Kossuth, IA

Built 1975 Load: 21.4 t ADT: 50

LOCAL

Poor

Over: DRAINAGE

075270305, Madison, IA

Built 1952 Load: 21.4 t ADT: 20

LOCAL

Poor

Over: N COAL CREEK

074171702, Mahaska, IA

Built 1956 Load: 21.4 t ADT: 71

LOCAL

Poor

Over: MUCHAKINOCK CREEK

076173518, Mahaska, IA

Built 1949 Load: 21.4 t ADT: 180

LOCAL

Poor

Over: CLEAR CREEK

083203204, Marshall, IA

Built 1950 Load: 21.4 t ADT: 11

LOCAL

Poor

Over: STREAM

099420502, Osceola, IA

Built 1943 Load: 21.4 t ADT: 21

JUNIPER AVE

Poor

Over: MINK CREEK

093461102, Plymouth, IA

Built 1900 Load: 21.4 t ADT: 45

LOCAL

Poor

Over: SMALL STREAM

078371001, Shelby, IA

Built 1976 Load: 21.4 t ADT: 15

LOCAL

Poor

Over: SMALL STREAM

072313501, Union, IA

Built 1964 Load: 21.4 t ADT: 11

380TH

Poor

Over: STREAM

098201601, Worth, IA

Built 1964 Load: 21.4 t ADT: 33

LOCAL

Poor

Over: CREEK

081350701, Audubon, IA

Built 1951 Load: 21.5 t ADT: 5

FM

Poor

Over: LONG CREEK

069033005, Des Moines, IA

Built 1950 Load: 21.5 t ADT: 60

FM

Poor

Over: LONG DICK CREEK

086230901, Hamilton, IA

Built 1924 Load: 21.5 t ADT: 30

FM LAREDO AVE

Poor

Over: ALLEN CREEK

080431706, Harrison, IA

Built 1942 Load: 21.5 t ADT: 139

LOCAL

Poor

Over: SMALL STREAM

073031704, Louisa, IA

Built 1974 Load: 21.5 t ADT: 51

LOCAL

Poor

Over: DRAINAGE

075282004, Madison, IA

Built 1948 Load: 21.5 t ADT: 26

CO ENTRANCE

Poor

Over: DRAINAGE

00000, Madison, IA

Built 1972 Load: 21.5 t ADT: 11

LOCAL

Poor

Over: SMALL

084172102, Marshall, IA

Built 1979 Load: 21.5 t ADT: 51

LOCAL

Poor

Over: CREEK

085193608, Marshall, IA

Built 1940 Load: 21.5 t ADT: 21

190TH ST

Poor

Over: DRAINAGE

092462301, Plymouth, IA

Built 1949 Load: 21.5 t ADT: 20

LOCAL B LEVEL

Poor

Over: SMALL STREAM

073283103, Union, IA

Built 1973 Load: 21.5 t ADT: 5

OSAGE RD

Poor

Over: POYNER CREEK

89-11-31-01-10, Black Hawk, IA

Built 1960 Load: 21.6 t ADT: 59

FM

Poor

Over: NICHOLSON CREEK

080042002, Cedar, IA

Built 1960 Load: 21.6 t ADT: 820

FM AMANA RD

Poor

Over: BR IOWA RIVER

081082403, Johnson, IA

Built 1935 Load: 21.6 t ADT: 130

FM

Poor

Over: DRAINAGE

075282203, Madison, IA

Built 1975 Load: 21.6 t ADT: 180

FM

Poor

Over: N SKUNK RIVER

083202805, Marshall, IA

Built 1917 Load: 21.6 t ADT: 79

LOCAL

Poor

Over: SUN VALLEY CREEK

070302806, Ringgold, IA

Built 1975 Load: 21.6 t ADT: 34

FIELD ENTRANCE

Poor

Over: SMALL STREAM

078373201, Shelby, IA

Built 1942 Load: 21.6 t ADT: 10

LOCAL-V AVE.

Poor

Over: SMALL CREEK

092390302, Cherokee, IA

Built 1917 Load: 21.7 t ADT: 26

FM 140TH AVE

Poor

Over: SMALL STREAM

088061102, Delaware, IA

Built 1972 Load: 21.7 t ADT: 69

LOCAL

Poor

Over: CREEK

090011303, Dubuque, IA

Built 1940 Load: 21.7 t ADT: 120

A AVE / N58

Poor

Over: RACCOON RIVER

084321802, Greene, IA

Built 1950 Load: 21.7 t ADT: 131

Showing 19,451-19,500 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.