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: NORTH SKUNK RIVER

080180806, Jasper, IA

Built 1936 Load: 3.9 t ADT: 106

FM

Poor

Over: SAND CREEK

071283005, Union, IA

Built 1963 Load: 3.9 t ADT: 50

LOCAL - CHICAGO

Poor

Over: BUCK CREEK

077361801, Cass, IA

Built 1900 Load: 4.0 t ADT: 30

LOCAL

Poor

Over: TRIB OF DICKENSON BRANCH

067260305, Decatur, IA

Built 1967 Load: 4.0 t ADT: 5

FM SPRUCE AVE

Poor

Over: MAYNES CREEK

091191802, Franklin, IA

Built 1952 Load: 4.0 t ADT: 49

LOCAL

Poor

Over: PRAIRIE CREEK

093271401, Humboldt, IA

Built 1900 Load: 4.0 t ADT: 15

LOCAL RD

Poor

Over: JONES CREEK

075273104, Madison, IA

Built 1979 Load: 4.0 t ADT: 45

LCL-MARH AVE

Poor

Over: NISHNA RIVER

071410201, Mills, IA

Built 1940 Load: 4.0 t ADT: 40

FM

Poor

Over: PAINTER CREEK

075252404, Warren, IA

Built 1900 Load: 4.0 t ADT: 71

FM

Poor

Over: CALHOUN CO DD

089320801, Calhoun, IA

Built 1976 Load: 4.1 t ADT: 45

LOCAL

Poor

Over: BRANCH OF BEAVER CREEK

089170602, Grundy, IA

Built 1953 Load: 4.1 t ADT: 40

LOCAL ROAD

Poor

Over: BEAVER CREEK

089170205, Grundy, IA

Built 1978 Load: 4.1 t ADT: 20

LOCAL

Poor

Over: SM STREAM

074071710, Washington, IA

Built 1934 Load: 4.1 t ADT: 11

LOCAL

Poor

Over: WOLF CREEK

089432802, Woodbury, IA

Built 1960 Load: 4.1 t ADT: 15

LOCAL

Poor

Over: INDIAN CREEK

068163404, Appanoose, IA

Built 1900 Load: 4.2 t ADT: 5

LOCAL

Poor

Over: CLARKS CREEK

074373204, Cass, IA

Built 1966 Load: 4.2 t ADT: 5

LOCAL

Poor

Over: WEST LITTLE RIVER

069261103, Decatur, IA

Built 1930 Load: 4.2 t ADT: 5

LOCAL

Poor

Over: DOWD CREEK

086182002, Grundy, IA

Built 1955 Load: 4.2 t ADT: 59

LOCAL

Poor

Over: TROUBLESOME CREEK

079332902, Guthrie, IA

Built 1957 Load: 4.2 t ADT: 20

LOCAL

Poor

Over: PUMPKIN CREEK

084E22003, Jackson, IA

Built 1950 Load: 4.2 t ADT: 11

FM

Poor

Over: DRAINAGE DITCH NO 69

088302301, Webster, IA

Built 1981 Load: 4.2 t ADT: 34

LOCAL

Poor

Over: N CHEQUEST LAKE CREEK

070123004, Davis, IA

Built 1940 Load: 4.3 t ADT: 15

LOCAL ROAD

Poor

Over: BRANCH BLACK HAWK CREEK

087160203, Grundy, IA

Built 1971 Load: 4.3 t ADT: 26

LOCAL

Poor

Over: TRIB TO MIDDLE RIVER

078332402, Guthrie, IA

Built 1966 Load: 4.3 t ADT: 34

MEDFORD AVE

Poor

Over: WILLOW RIVER

079432102, Harrison, IA

Built 1900 Load: 4.3 t ADT: 89

HOWARD AVE

Poor

Over: BR CRANE CREEK

098132004, Howard, IA

Built 1947 Load: 4.3 t ADT: 48

LOCAL

Poor

Over: WOLF CREEK

071080509, Jefferson, IA

Built 1900 Load: 4.3 t ADT: 15

LOCAL

Poor

Over: BRANCH NORTH WOLF CREEK

074220802, Warren, IA

Built 1950 Load: 4.3 t ADT: 15

200TH

Poor

Over: CREEK

095201801, Cerro Gordo, IA

Built 1937 Load: 4.4 t ADT: 21

LOCAL

Poor

Over: CARTERS CREEK

068142102, Davis, IA

Built 1967 Load: 4.4 t ADT: 30

FM

Poor

Over: CREEK

088193105, Hardin, IA

Built 1977 Load: 4.4 t ADT: 73

LOCAL

Poor

Over: BRUSH CREEK

082172705, Marshall, IA

Built 1977 Load: 4.4 t ADT: 47

LOCAL

Poor

Over: PIKE CREEK

076041603, Muscatine, IA

Built 1900 Load: 4.4 t ADT: 41

FILBERT AVENUE

Poor

Over: WEST FORK 102 RIVER

071343102, Adams, IA

Built 1984 Load: 4.5 t ADT: 5

LOCAL

Poor

Over: VILLAGE CREEK

098031806, Allamakee, IA

Built 1900 Load: 4.5 t ADT: 10

KIPLING AVE.

Poor

Over: COLD WATER CREEK

093171404, Butler, IA

Built 1915 Load: 4.5 t ADT: 30

BRIDGE ST

Poor

Over: TURKEY RIVER

C25050530, Clayton, IA

Built 1889 Load: 4.5 t ADT: 4,755

LOCAL

Poor

Over: TRIB FABIUS CREEK

067140705, Davis, IA

Built 1966 Load: 4.5 t ADT: 11

FM

Poor

Over: MIDDLE RIVER

079333604, Guthrie, IA

Built 1969 Load: 4.5 t ADT: 450

LOCAL

Poor

Over: OLD MAN'S CREEK

080113602, Iowa, IA

Built 1975 Load: 4.5 t ADT: 34

G13 110TH ST

Poor

Over: N SKUNK RIVER

077150703, Mahaska, IA

Built 1960 Load: 4.5 t ADT: 35

LOCAL

Poor

Over: CREEK

083171108, Marshall, IA

Built 1916 Load: 4.5 t ADT: 145

KIWI AVENUE

Poor

Over: BUCK CREEK

068382308, Page, IA

Built 1994 Load: 4.5 t ADT: 20

165TH ST

Poor

Over: WEST BRANCH FLOYD RIVER

092450603, Plymouth, IA

Built 1911 Load: 4.5 t ADT: 120

LOCAL

Poor

Over: E BRANCH W. NISH. RIVER

801337, Shelby, IA

Built 1920 Load: 4.5 t ADT: 26

720TH AVE

Poor

Over: HARDIN-STORY DD 1

085211104, Story, IA

Built 1900 Load: 4.5 t ADT: 15

LOCAL

Poor

Over: STREAM

068200104, Wayne, IA

Built 1980 Load: 4.5 t ADT: 5

LOCAL

Poor

Over: WALNUT CR

069203604, Wayne, IA

Built 1977 Load: 4.5 t ADT: 40

LOCAL

Poor

Over: FARMERS DITCH

088472604, Woodbury, IA

Built 2000 Load: 4.5 t ADT: 30

QUINCE AVE

Poor

Over: STREAM

071333602, Adams, IA

Built 1978 Load: 4.6 t ADT: 20

Showing 17,201-17,250 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.