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

LCL-ELLINGTON

Poor

Over: KEG CREEK

073423103, Mills, IA

Built 1964 Load: 6.3 t ADT: 41

FM

Poor

Over: HONEY CREEK

068331402, Taylor, IA

Built 1958 Load: 6.3 t ADT: 11

LOCAL

Poor

Over: BIG INDIAN CREEK

068100705, Van Buren, IA

Built 1960 Load: 6.3 t ADT: 21

140TH ST

Poor

Over: FLOYD RIVER

093452605, Plymouth, IA

Built 1954 Load: 6.4 t ADT: 60

LOCAL

Poor

Over: STREAM

068293403, Ringgold, IA

Built 1916 Load: 6.4 t ADT: 15

LOCAL

Poor

Over: CREEK

096100403, Winneshiek, IA

Built 1900 Load: 6.4 t ADT: 88

LOCAL

Poor

Over: STREAM

088430602, Woodbury, IA

Built 1950 Load: 6.4 t ADT: 5

355TH ST

Poor

Over: LITTLE SIOUX RIVER

096371106, Clay, IA

Built 1905 Load: 6.5 t ADT: 41

35TH AVE

Poor

Over: CREEK

080E12204, Scott, IA

Built 1965 Load: 6.5 t ADT: 51

FM

Poor

Over: IOWA RIVER OVERFLOW

082132002, Tama, IA

Built 1968 Load: 6.5 t ADT: 786

LOCAL

Poor

Over: SMALL STREAM

069091501, Van Buren, IA

Built 1976 Load: 6.5 t ADT: 26

FM

Poor

Over: DRAINAGE DITCH

099252902, Winnebago, IA

Built 1955 Load: 6.5 t ADT: 34

LOCAL

Poor

Over: HONEY CREEK

087222203, Hardin, IA

Built 1988 Load: 6.6 t ADT: 30

LOCAL

Poor

Over: STREAM

067292401, Ringgold, IA

Built 1959 Load: 6.6 t ADT: 11

LOCAL

Poor

Over: CREEK

068083003, Van Buren, IA

Built 1959 Load: 6.6 t ADT: 11

LOCAL ROAD

Poor

Over: UPPER IOWA RIVER

100101803, Winneshiek, IA

Built 1904 Load: 6.7 t ADT: 20

LOCAL

Poor

Over: MCELHANEY CREEK

089442702, Woodbury, IA

Built 1960 Load: 6.7 t ADT: 40

LOCAL

Poor

Over: BROWN CREEK

100332001, Emmet, IA

Built 1971 Load: 6.8 t ADT: 15

340 AVENUE

Poor

Over: DEER CREEK

070411102, Fremont, IA

Built 1962 Load: 6.8 t ADT: 5

LOCAL

Poor

Over: DD

093293502, Humboldt, IA

Built 1938 Load: 6.8 t ADT: 11

LOC RD CLASS B

Poor

Over: STREAM

076101804, Keokuk, IA

Built 1970 Load: 6.8 t ADT: 11

150TH STREET

Poor

Over: STREAM

070373601, Page, IA

Built 1941 Load: 6.8 t ADT: 26

LOCAL

Poor

Over: M FK GRAND RIVER

067300901, Ringgold, IA

Built 1981 Load: 6.8 t ADT: 20

LOCAL

Poor

Over: WALKER CREEK

070202202, Wayne, IA

Built 1983 Load: 6.8 t ADT: 30

LOCAL

Poor

Over: BRANCH MIDDLE NODAWAY R

074333602, Adair, IA

Built 1960 Load: 6.9 t ADT: 15

LOCAL

Poor

Over: BUCK BRANCH

070183606, Appanoose, IA

Built 1954 Load: 6.9 t ADT: 16

COUNTY ROAD

Poor

Over: PANTHER CREEK

079280502, Dallas, IA

Built 1964 Load: 6.9 t ADT: 35

LOCAL

Poor

Over: MCPHERSON CREEK

070430106, Fremont, IA

Built 1979 Load: 6.9 t ADT: 5

LOCAL

Poor

Over: DRAINAGE DITCH

089230701, Hamilton, IA

Built 1975 Load: 6.9 t ADT: 15

LOCAL

Poor

Over: HONEY CREEK

086211402, Hardin, IA

Built 1982 Load: 6.9 t ADT: 29

LCL-QUIGG AVE

Poor

Over: SPRING VALLEY CR

071422605, Mills, IA

Built 1940 Load: 6.9 t ADT: 11

LOCAL

Poor

Over: DRAINAGE

072373401, Montgomery, IA

Built 1966 Load: 6.9 t ADT: 11

LOCAL

Poor

Over: SAND CREEK

070281503, Ringgold, IA

Built 1958 Load: 6.9 t ADT: 15

GRANITE AVE

Poor

Over: BROKEN KETTLE CREEK

093473402, Plymouth, IA

Built 1900 Load: 7.0 t ADT: 34

LOCAL

Poor

Over: MALONE CR

089092405, Buchanan, IA

Built 1925 Load: 7.1 t ADT: 20

FM

Poor

Over: MILL CREEK

082020104, Cedar, IA

Built 1956 Load: 7.1 t ADT: 550

LOCAL 220 AVE

Poor

Over: STREAM

089043102, Delaware, IA

Built 1967 Load: 7.1 t ADT: 26

LOCAL ROAD

Poor

Over: BRANCH BIG CREEK

072052005, Henry, IA

Built 1977 Load: 7.1 t ADT: 11

LOCAL

Poor

Over: BR CARRUTHERS CREEK

073201104, Lucas, IA

Built 1956 Load: 7.1 t ADT: 11

LOCAL

Poor

Over: NORTH ENGLISH RIVER

079142004, Poweshiek, IA

Built 1951 Load: 7.1 t ADT: 20

LOCAL

Poor

Over: ELKHORN CREEK

078371603, Shelby, IA

Built 1958 Load: 7.1 t ADT: 21

LOCAL

Poor

Over: W FORK NODAWAY RIVER

074331603, Adair, IA

Built 1949 Load: 7.2 t ADT: 30

LOCAL

Poor

Over: SMALL STREAM

091162903, Butler, IA

Built 1970 Load: 7.2 t ADT: 11

LOCAL - 740TH

Poor

Over: CREEK

076343302, Cass, IA

Built 1900 Load: 7.2 t ADT: 26

BIG CREEK RD.

Poor

Over: BIG CREEK

000000000, Linn, IA

Built 1929 Load: 7.2 t ADT: 130

LCL-QUEEN AVE

Poor

Over: DEER CREEK

071403003, Mills, IA

Built 1940 Load: 7.2 t ADT: 15

FM

Poor

Over: GRAYS CREEK

073172402, Monroe, IA

Built 1951 Load: 7.2 t ADT: 45

LOCAL

Poor

Over: DRAINAGE

073192507, Monroe, IA

Built 1952 Load: 7.2 t ADT: 50

FARM ENTRANCE

Poor

Over: DRAINAGE DITCH(SDB)

076020702, Muscatine, IA

Built 1920 Load: 7.2 t ADT: 10

FM

Poor

Over: E FORK GRAND RIVER

068292704, Ringgold, IA

Built 1959 Load: 7.2 t ADT: 20

Showing 17,351-17,400 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.