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 ROAD

Poor

Over: CREEK

097091101, Winneshiek, IA

Built 1900 Load: 7.8 t ADT: 44

LOCAL - AKRON

Poor

Over: TROUBLESOME CREEK

077350203, Cass, IA

Built 1900 Load: 7.9 t ADT: 5

COUNTY ROAD

Poor

Over: MOSQUITO CREEK

080290502, Dallas, IA

Built 1942 Load: 7.9 t ADT: 72

LOCAL ROAD

Poor

Over: LITTLE ROCK RIVER

098452907, Lyon, IA

Built 1900 Load: 7.9 t ADT: 62

LOCAL

Poor

Over: MUCHAKINOCK CREEK

076172704, Mahaska, IA

Built 1957 Load: 7.9 t ADT: 100

FM

Poor

Over: SUN VALLEY CREEK

070302502, Ringgold, IA

Built 1961 Load: 7.9 t ADT: 50

FM

Poor

Over: DRAINAGE DITCH

067342703, Taylor, IA

Built 1940 Load: 7.9 t ADT: 26

LOCAL ROAD

Poor

Over: BRANCH OTTER CREEK

074230604, Warren, IA

Built 1970 Load: 7.9 t ADT: 30

LOCAL

Poor

Over: ELK CREEK

069270604, Decatur, IA

Built 1961 Load: 8.0 t ADT: 15

117TH ST

Poor

Over: SAND CREEK

070271706, Decatur, IA

Built 1900 Load: 8.0 t ADT: 11

FM

Poor

Over: BEAR CREEK

079322606, Guthrie, IA

Built 1959 Load: 8.0 t ADT: 60

1860 210TH ST

Poor

Over: EAST IOWA RIVER

095241201, Hancock, IA

Built 1967 Load: 8.0 t ADT: 259

LOCAL

Poor

Over: TIPTON CREEK

087212602, Hardin, IA

Built 1983 Load: 8.0 t ADT: 51

LCL-400TH ST

Poor

Over: INDIAN CREEK

072401102, Mills, IA

Built 1940 Load: 8.0 t ADT: 26

210TH STREET

Poor

Over: STREAM

072333403, Adams, IA

Built 1966 Load: 8.1 t ADT: 11

XAVIER AVENUE

Poor

Over: E. FORK E NODAWAY RIVER

073322404, Adams, IA

Built 1974 Load: 8.1 t ADT: 40

LOCAL

Poor

Over: CREEK

079343005, Audubon, IA

Built 1967 Load: 8.1 t ADT: 11

LOCAL

Poor

Over: PRAIRIE CREEK

084112904, Benton, IA

Built 1970 Load: 8.1 t ADT: 50

LOCAL

Poor

Over: RACCOON RIVER

091361503, Buena Vista, IA

Built 1933 Load: 8.1 t ADT: 34

LOCAL

Poor

Over: NORTH WHITE BREAST CREEK

071240604, Clarke, IA

Built 1982 Load: 8.1 t ADT: 15

LOCAL

Poor

Over: W FK W NISHNABOTNA RIVER

082381201, Crawford, IA

Built 1945 Load: 8.1 t ADT: 30

LOCAL

Poor

Over: TRIB TO MASON CREEK

079322806, Guthrie, IA

Built 1957 Load: 8.1 t ADT: 20

LOCAL

Poor

Over: MUCHAKINOCH CREEK

075161710, Mahaska, IA

Built 1951 Load: 8.1 t ADT: 60

130TH ST

Poor

Over: W BR FLOYD RIVER

093451901, Plymouth, IA

Built 1900 Load: 8.1 t ADT: 20

FM

Poor

Over: BRANCH, SKUNK RIVER

081231301, Polk, IA

Built 1968 Load: 8.1 t ADT: 139

LOCAL

Poor

Over: WALNUT CREEK

069303506, Ringgold, IA

Built 1956 Load: 8.1 t ADT: 15

LOCAL

Poor

Over: SUN VALLEY CREEK

070302606, Ringgold, IA

Built 1980 Load: 8.1 t ADT: 5

LOCAL

Poor

Over: BR RACCOON RIVER

091361001, Buena Vista, IA

Built 1923 Load: 8.2 t ADT: 20

400 AVENUE

Poor

Over: STREAM

068403406, Fremont, IA

Built 1966 Load: 8.2 t ADT: 5

LOCAL ROAD

Poor

Over: SOUTH FORK BEAVER CREEK

088180101, Grundy, IA

Built 1948 Load: 8.2 t ADT: 44

LOCAL

Poor

Over: BR MIDDLE FORK ENGLISH R

078121306, Iowa, IA

Built 1925 Load: 8.2 t ADT: 11

FM

Poor

Over: BRANCH CROOKED CREEK

069301401, Ringgold, IA

Built 1957 Load: 8.2 t ADT: 71

LOCAL

Poor

Over: CREEK

070332302, Taylor, IA

Built 1953 Load: 8.2 t ADT: 11

LOCAL

Poor

Over: NORTH FORK LONG CREEK

076072901, Washington, IA

Built 1929 Load: 8.2 t ADT: 5

LOCAL QUAIL AVE

Poor

Over: BEAVER CREEK

090202302, Franklin, IA

Built 1954 Load: 8.3 t ADT: 11

MIRACLE LN

Poor

Over: STREAM

079313203, Guthrie, IA

Built 1950 Load: 8.3 t ADT: 11

LOCAL

Poor

Over: LOCAL STREAM

073050802, Henry, IA

Built 1968 Load: 8.3 t ADT: 41

VALE RD

Poor

Over: NICHOLS CR

100112704, Howard, IA

Built 1949 Load: 8.3 t ADT: 42

LOCAL

Poor

Over: BR.WALNUT CREEK

073082003, Jefferson, IA

Built 1950 Load: 8.3 t ADT: 34

LCL-400TH ST

Poor

Over: HUNTERS BRANCH

071402602, Mills, IA

Built 1965 Load: 8.3 t ADT: 26

TEAK AVE

Poor

Over: STREAM

070362104, Page, IA

Built 1999 Load: 8.3 t ADT: 5

LOCAL

Poor

Over: HOG BRANCH

069331302, Taylor, IA

Built 1961 Load: 8.3 t ADT: 5

LOCAL

Poor

Over: WEST 102 RIVER

070350103, Taylor, IA

Built 1955 Load: 8.3 t ADT: 11

CARTER AVE

Poor

Over: DD

087302102, Webster, IA

Built 1959 Load: 8.3 t ADT: 11

LOCAL

Poor

Over: STREAM

069253008, Decatur, IA

Built 1960 Load: 8.4 t ADT: 190

LOCAL

Poor

Over: CREEK

090E20905, Dubuque, IA

Built 1925 Load: 8.4 t ADT: 44

LOCAL

Poor

Over: SMALL STREAM

081333002, Guthrie, IA

Built 1987 Load: 8.4 t ADT: 29

LOCAL RD

Poor

Over: MIDDLE RIVER

075281302, Madison, IA

Built 1948 Load: 8.4 t ADT: 45

LOCAL

Poor

Over: LITTLE BLUFF CK

074173505, Mahaska, IA

Built 1955 Load: 8.4 t ADT: 50

LOCAL

Poor

Over: MOON CREEK

077150101, Mahaska, IA

Built 1952 Load: 8.4 t ADT: 40

Showing 17,451-17,500 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.