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: STREAM

079140702, Poweshiek, IA

Built 1956 Load: 16.7 t ADT: 11

FM

Poor

Over: ROCK CREEK

081133101, Poweshiek, IA

Built 1973 Load: 16.7 t ADT: 50

LOCAL

Poor

Over: WALNUT CREEK

069292103, Ringgold, IA

Built 1964 Load: 16.7 t ADT: 11

FM

Poor

Over: S RIVER

075240504, Warren, IA

Built 1949 Load: 16.7 t ADT: 807

GRIMES ST

Poor

Over: BRANCH NORTH RIVER

076250705, Warren, IA

Built 2000 Load: 16.7 t ADT: 15

415TH

Poor

Over: DRAINAGE

099202605, Worth, IA

Built 1900 Load: 16.7 t ADT: 26

LOCAL

Poor

Over: DRAINAGE DITCH 9

091251903, Wright, IA

Built 1920 Load: 16.7 t ADT: 11

APPLE AVENUE

Poor

Over: STREAM

071350704, Adams, IA

Built 1964 Load: 16.8 t ADT: 5

LOCAL

Poor

Over: YELLOW RIVER

096041804, Allamakee, IA

Built 1954 Load: 16.8 t ADT: 128

FM 240 ST

Poor

Over: STREAM

088051701, Delaware, IA

Built 1930 Load: 16.8 t ADT: 79

FM

Poor

Over: ENGLISH RIVER

078093102, Iowa, IA

Built 1957 Load: 16.8 t ADT: 50

FM

Poor

Over: DRAINAGE

071080804, Jefferson, IA

Built 1900 Load: 16.8 t ADT: 50

LOCAL

Poor

Over: STREAM

071091905, Jefferson, IA

Built 1977 Load: 16.8 t ADT: 60

LOCAL

Poor

Over: S FORK ENGLISH RIVER

077130902, Keokuk, IA

Built 1970 Load: 16.8 t ADT: 26

FM 460TH ST

Poor

Over: MIDDLE BRANCH BLUE EARTH

099270601, Kossuth, IA

Built 1967 Load: 16.8 t ADT: 5

FM

Poor

Over: MINERVA CREEK

084201602, Marshall, IA

Built 1916 Load: 16.8 t ADT: 147

LOCAL

Poor

Over: LINN CR

084203602, Marshall, IA

Built 1916 Load: 16.8 t ADT: 157

FM

Poor

Over: LITTLE SIOUX RIVER

085441603, Monona, IA

Built 1961 Load: 16.8 t ADT: 150

FM

Poor

Over: FAMERS GARRETSON DITCH

085450404, Monona, IA

Built 1962 Load: 16.8 t ADT: 578

LOCAL

Poor

Over: CREEK

098390504, Osceola, IA

Built 1936 Load: 16.8 t ADT: 62

LOCAL

Poor

Over: DRAINAGE

090461903, Plymouth, IA

Built 1955 Load: 16.8 t ADT: 30

IMPALA AVE

Poor

Over: MINK CREEK

092460502, Plymouth, IA

Built 1938 Load: 16.8 t ADT: 26

FIR AVE

Poor

Over: BULL RUN

092473302, Plymouth, IA

Built 1948 Load: 16.8 t ADT: 30

180TH ST

Poor

Over: WESTFIELD CREEK

092481501, Plymouth, IA

Built 1948 Load: 16.8 t ADT: 20

LOCAL

Poor

Over: STREAM

070312002, Ringgold, IA

Built 1957 Load: 16.8 t ADT: 11

LOCAL

Poor

Over: NO NAME CREEK

086373502, Sac, IA

Built 1964 Load: 16.8 t ADT: 45

LOCAL

Poor

Over: SMALL STREAM

073283601, Union, IA

Built 1943 Load: 16.8 t ADT: 30

LOCAL

Poor

Over: STREAM

068220102, Wayne, IA

Built 1967 Load: 16.8 t ADT: 60

FM

Poor

Over: LIZARD CREEK

089300104, Webster, IA

Built 1965 Load: 16.8 t ADT: 549

FM

Poor

Over: LIZARD CREEK

089301206, Webster, IA

Built 1965 Load: 16.8 t ADT: 549

LOCAL

Poor

Over: RUTT BRANCH

075320402, Adair, IA

Built 1900 Load: 16.9 t ADT: 35

LOCAL

Poor

Over: BR MINERVA CR

085200804, Marshall, IA

Built 1917 Load: 16.9 t ADT: 15

LOCAL

Poor

Over: SUGAR CREEK

083160506, Tama, IA

Built 1900 Load: 16.9 t ADT: 88

ADAMS-MONTGOM.

Poor

Over: SIN CREEK

073351904, Adams, IA

Built 1979 Load: 17.0 t ADT: 5

LOCAL RD

Poor

Over: BR SUTTLE CREEK

096043004, Allamakee, IA

Built 1900 Load: 17.0 t ADT: 70

FM

Poor

Over: BRANCH YELLOW RIVER

096061608, Allamakee, IA

Built 1922 Load: 17.0 t ADT: 373

FM

Poor

Over: PRAIRIE CREEK

082103001, Benton, IA

Built 1900 Load: 17.0 t ADT: 80

FM

Poor

Over: BR LITTLE BEAR CREEK

083101302, Benton, IA

Built 1929 Load: 17.0 t ADT: 422

FM

Poor

Over: BEAR CREEK

083101306, Benton, IA

Built 1957 Load: 17.0 t ADT: 1,414

10TH AVE

Poor

Over: MINNOW CREEK

082122301, Benton, IA

Built 1900 Load: 17.0 t ADT: 349

BIG WOODS RD

Poor

Over: TRIB TO CEDAR RIVER

90-13-18-02-10, Black Hawk, IA

Built 1953 Load: 17.0 t ADT: 59

FM

Poor

Over: BROOKS CREEK

091370802, Buena Vista, IA

Built 1966 Load: 17.0 t ADT: 509

LOCAL

Poor

Over: DRAINAGE DITCH

091372402, Buena Vista, IA

Built 1971 Load: 17.0 t ADT: 100

FM

Poor

Over: CEDAR CREEK

086323501, Calhoun, IA

Built 1938 Load: 17.0 t ADT: 34

FM - LANSING

Poor

Over: WATERWAY

076363401, Cass, IA

Built 1900 Load: 17.0 t ADT: 379

FM-L AVE.

Poor

Over: SMALL CREEK

092412402, Cherokee, IA

Built 1900 Load: 17.0 t ADT: 429

220 ST

Poor

Over: BR ROBINSON CREEK

088060401, Delaware, IA

Built 1922 Load: 17.0 t ADT: 1,061

FM 170 ST

Poor

Over: SMALL STREAM

089040807, Delaware, IA

Built 1955 Load: 17.0 t ADT: 79

LOCAL

Poor

Over: EAST FORK CROOKED CREEK

072040503, Des Moines, IA

Built 1950 Load: 17.0 t ADT: 26

LOCAL

Poor

Over: CREEK

088023004, Dubuque, IA

Built 1928 Load: 17.0 t ADT: 78

Showing 18,651-18,700 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.