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

FM ADDISON AVE

Poor

Over: WAPSIPINICON RIVER

099140702, Howard, IA

Built 1968 Load: 31.4 t ADT: 285

FM

Poor

Over: SMALL

084E63303, Jackson, IA

Built 1980 Load: 31.4 t ADT: 80

FM

Poor

Over: SMALL STREAM

087E41405, Jackson, IA

Built 1986 Load: 31.4 t ADT: 40

FM

Poor

Over: WHITE BREAST CREEK

073222205, Lucas, IA

Built 1957 Load: 31.4 t ADT: 440

310TH ST

Poor

Over: STREAM

071413202, Mills, IA

Built 1960 Load: 31.4 t ADT: 325

FM

Poor

Over: SS #98

094331101, Palo Alto, IA

Built 1973 Load: 31.4 t ADT: 120

FM

Poor

Over: D D #66 BR SO LIZARD CK

090331201, Pocahontas, IA

Built 1970 Load: 31.4 t ADT: 71

FM

Poor

Over: BRANCH SALT CREEK

084130603, Tama, IA

Built 1996 Load: 31.4 t ADT: 344

P13 VALLEY AVE

Poor

Over: DD #83

087311702, Calhoun, IA

Built 1917 Load: 31.5 t ADT: 60

FM 255TH ST

Poor

Over: BEAVERDAM CREEK

093200103, Franklin, IA

Built 1969 Load: 31.5 t ADT: 687

S14/620TH AVE

Poor

Over: CALAMUS CREEK

082221802, Story, IA

Built 1941 Load: 31.5 t ADT: 988

FM

Poor

Over: PRAIRIE CREEK

082110801, Benton, IA

Built 1959 Load: 31.6 t ADT: 45

FM

Poor

Over: IOWA RIVER

082132002, Tama, IA

Built 1968 Load: 31.6 t ADT: 786

LOCAL

Poor

Over: WEASEL CK

082100701, Benton, IA

Built 1957 Load: 31.7 t ADT: 28

LOCAL

Poor

Over: LITTLE TURKEY

096111101, Chickasaw, IA

Built 1969 Load: 31.7 t ADT: 47

HWY 147

Poor

Over: FLOOD CREEK

095171501, Floyd, IA

Built 1930 Load: 31.7 t ADT: 668

200 TH

Poor

Over: CREEK

084323001, Greene, IA

Built 1956 Load: 31.7 t ADT: 35

FAS 3556

Poor

Over: CREEK

086230602, Hamilton, IA

Built 1947 Load: 31.7 t ADT: 478

125TH ST

Poor

Over: BR CRANE CREEK

098130303, Howard, IA

Built 1955 Load: 31.7 t ADT: 10

FM

Poor

Over: SM STREAM

075093109, Washington, IA

Built 1928 Load: 31.7 t ADT: 10

FM 130TH AVE

Poor

Over: OCHEYEDAN RIVER

096381002, Clay, IA

Built 1971 Load: 31.8 t ADT: 1,287

FM

Poor

Over: ROCK CREEK

076121802, Keokuk, IA

Built 1956 Load: 31.8 t ADT: 35

FM

Poor

Over: BRANCH BURNETTE CREEK

084170603, Marshall, IA

Built 1984 Load: 31.8 t ADT: 304

240TH AVE

Poor

Over: CREEK

080E41306, Scott, IA

Built 1962 Load: 31.8 t ADT: 870

LOCAL

Poor

Over: SMALL STREAM

094132401, Chickasaw, IA

Built 1982 Load: 31.9 t ADT: 11

LOCAL

Poor

Over: LITTLE WAPSIPINICON RVR

095131601, Chickasaw, IA

Built 1980 Load: 31.9 t ADT: 88

E 92ND ST S

Poor

Over: SMALL

078180306, Jasper, IA

Built 1979 Load: 31.9 t ADT: 35

IOWA AVE

Poor

Over: IOWA RIVER

79060900, Johnson, IA

Built 1916 Load: 31.9 t ADT: 5,400

FM

Poor

Over: CREEK

096132801, Chickasaw, IA

Built 1976 Load: 32.0 t ADT: 88

FM

Poor

Over: LITTLE CEDAR

096153505, Floyd, IA

Built 1967 Load: 32.0 t ADT: 59

180TH ST

Poor

Over: LITTLE TURKEY RIVER

097110601, Howard, IA

Built 1985 Load: 32.0 t ADT: 29

FM

Poor

Over: TARKIO CREEK TRIB

071373301, Montgomery, IA

Built 1959 Load: 32.0 t ADT: 219

FM

Poor

Over: WEXFORD CREEK

098032506, Allamakee, IA

Built 1970 Load: 32.1 t ADT: 530

FM 160TH AVE

Poor

Over: WILLOW CREEK

095373002, Clay, IA

Built 1962 Load: 32.1 t ADT: 190

LOCAL

Poor

Over: E FK GRAND RIVER

068292701, Ringgold, IA

Built 1961 Load: 32.1 t ADT: 26

LCL-410TH ST

Poor

Over: INDIAN CREEK

072402604, Mills, IA

Built 1950 Load: 32.2 t ADT: 51

FM

Poor

Over: STREAM

069301006, Ringgold, IA

Built 1941 Load: 32.2 t ADT: 71

FM

Poor

Over: OPOSSUM CREEK

084101601, Benton, IA

Built 1959 Load: 32.3 t ADT: 1,090

LOCAL RD

Poor

Over: DRAINAGE DITCH

095121902, Chickasaw, IA

Built 1954 Load: 32.3 t ADT: 2,396

300TH ST.

Poor

Over: QUINN CREEK

095070703, Fayette, IA

Built 1997 Load: 32.3 t ADT: 29

330 TH / E63

Poor

Over: DRAINAGE DITCH 9-13

082323101, Greene, IA

Built 1970 Load: 32.3 t ADT: 379

LOCAL

Poor

Over: BR WAPSIPINICON RIVER

097140402, Howard, IA

Built 1988 Load: 32.3 t ADT: 31

FM

Poor

Over: PLUM CREEK

098480102, Lyon, IA

Built 1968 Load: 32.3 t ADT: 210

LOCAL

Poor

Over: SMALL STREAM

803037, Shelby, IA

Built 1959 Load: 32.3 t ADT: 35

MAIN ST L43

Poor

Over: BACON CREEK

088410108, Woodbury, IA

Built 1958 Load: 32.3 t ADT: 383

RACINE AVE

Poor

Over: DRAINAGE DITCH

088082304, Buchanan, IA

Built 1953 Load: 32.4 t ADT: 2,671

FM

Poor

Over: LYTLE CREEK

087E20903, Dubuque, IA

Built 1977 Load: 32.4 t ADT: 50

LOCAL

Poor

Over: SOUTH FORK CATFISH CREEK

089E23304, Dubuque, IA

Built 1926 Load: 32.4 t ADT: 756

LOCAL

Poor

Over: CREEK

069100606, Van Buren, IA

Built 1964 Load: 32.4 t ADT: 11

FM

Poor

Over: WOLF CREEK

073290104, Union, IA

Built 1976 Load: 32.5 t ADT: 60

Showing 20,401-20,450 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.