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

FA-GASTON AVE

Poor

Over: DRAINAGE

072410605, Mills, IA

Built 1951 Load: 24.3 t ADT: 139

FM

Poor

Over: AVERY CREEK

071160203, Monroe, IA

Built 1958 Load: 24.3 t ADT: 80

FM

Poor

Over: LITTLE TARKIO

071383501, Montgomery, IA

Built 1958 Load: 24.3 t ADT: 219

FM

Poor

Over: CRABAPPLE CREEK

073393501, Montgomery, IA

Built 1958 Load: 24.3 t ADT: 199

300TH ST

Poor

Over: MUD CREEK

090451301, Plymouth, IA

Built 1950 Load: 24.3 t ADT: 50

190TH ST

Poor

Over: BULL RUN

092472101, Plymouth, IA

Built 1961 Load: 24.3 t ADT: 50

CO.RD.

Poor

Over: STREAM

083132002, Tama, IA

Built 1965 Load: 24.3 t ADT: 20

LOCAL

Poor

Over: CREEK

073141703, Wapello, IA

Built 1925 Load: 24.3 t ADT: 21

LOCAL ROAD

Poor

Over: BOHEMIAN CREEK

097101102, Winneshiek, IA

Built 1922 Load: 24.3 t ADT: 88

FM

Poor

Over: DRAINAGE DITCH

087461901, Woodbury, IA

Built 1960 Load: 24.3 t ADT: 369

FM

Poor

Over: DRAINAGE DITCH

087462016, Woodbury, IA

Built 1960 Load: 24.3 t ADT: 230

LOCAL

Poor

Over: STREAM

085331703, Carroll, IA

Built 1970 Load: 24.4 t ADT: 120

VINE ST

Poor

Over: ROCK FALLS CREEK

097190302, Cerro Gordo, IA

Built 1966 Load: 24.4 t ADT: 324

LOCAL

Poor

Over: CREEK

084E11803, Jackson, IA

Built 1915 Load: 24.4 t ADT: 211

LOCAL

Poor

Over: LAMALEES CREEK

066053506, Lee, IA

Built 1957 Load: 24.4 t ADT: 150

E AVE NORTHWEST

Poor

Over: CEDAR RIVER

000000000, Linn, IA

Built 1979 Load: 24.4 t ADT: 3,447

LOCAL ROAD

Poor

Over: KLONDIKE CREEK

099480104, Lyon, IA

Built 1900 Load: 24.4 t ADT: 41

LOCAL

Poor

Over: DRAINAGE

077261103, Madison, IA

Built 1967 Load: 24.4 t ADT: 11

LOCAL

Poor

Over: SMALL STREAM

086361502, Sac, IA

Built 1985 Load: 24.4 t ADT: 30

LOCAL

Poor

Over: DEER CREEK

090292203, Webster, IA

Built 1925 Load: 24.4 t ADT: 45

FM

Poor

Over: STREAM-D.D.196

086301204, Webster, IA

Built 1900 Load: 24.4 t ADT: 748

240TH STREET

Poor

Over: SAYLINGS CREEK

071321801, Adams, IA

Built 1978 Load: 24.5 t ADT: 26

LOCAL

Poor

Over: CREEK

080352001, Audubon, IA

Built 1934 Load: 24.5 t ADT: 216

LOCAL - NSHNA V

Poor

Over: SMALL STREAM

075370903, Cass, IA

Built 1986 Load: 24.5 t ADT: 62

LOCAL - 560TH

Poor

Over: CREEK

075372802, Cass, IA

Built 1983 Load: 24.5 t ADT: 269

LOCAL - 665TH

Poor

Over: CREEK

076351804, Cass, IA

Built 1983 Load: 24.5 t ADT: 51

LOCAL - 635TH

Poor

Over: TROUBLESOME CREEK

076360301, Cass, IA

Built 1979 Load: 24.5 t ADT: 30

LOCAL- S AVE

Poor

Over: CREEK

090391902, Cherokee, IA

Built 1916 Load: 24.5 t ADT: 15

FM

Poor

Over: EAST WAPSIPINICON RIVER

096132501, Chickasaw, IA

Built 1981 Load: 24.5 t ADT: 59

LOCAL

Poor

Over: BEAR CREEK

078283205, Dallas, IA

Built 1949 Load: 24.5 t ADT: 180

LOCAL

Poor

Over: SMALL STREAM

069040705, Des Moines, IA

Built 1970 Load: 24.5 t ADT: 26

LOCAL

Poor

Over: SMALL STREAM

069040805, Des Moines, IA

Built 1970 Load: 24.5 t ADT: 26

FM

Poor

Over: PAUL CREEK

072020703, Des Moines, IA

Built 1957 Load: 24.5 t ADT: 130

MAIN STREET SOUTH

Poor

Over: SMALL CREEK

069020406, Des Moines, IA

Built 1886 Load: 24.5 t ADT: 3,705

210TH ST

Poor

Over: CREEK

098380601, Dickinson, IA

Built 1987 Load: 24.5 t ADT: 5

260TH ST

Poor

Over: CREEK

098373301, Dickinson, IA

Built 1980 Load: 24.5 t ADT: 315

FM 115TH ST

Poor

Over: SMALL STREAM

091191303, Franklin, IA

Built 1965 Load: 24.5 t ADT: 59

LOCAL

Poor

Over: DEER CREEK

078301507, Guthrie, IA

Built 1985 Load: 24.5 t ADT: 20

LOCAL

Poor

Over: BEAVER CREEK

088200602, Hardin, IA

Built 1987 Load: 24.5 t ADT: 51

FM

Poor

Over: SUGAR CREEK

073071402, Henry, IA

Built 1960 Load: 24.5 t ADT: 640

FM

Poor

Over: CREEK

086413601, Ida, IA

Built 1971 Load: 24.5 t ADT: 350

FM

Poor

Over: UNNAMED CREEK

088391302, Ida, IA

Built 1900 Load: 24.5 t ADT: 369

LOCAL

Poor

Over: LITTLE BEAR CREEK

080111704, Iowa, IA

Built 1978 Load: 24.5 t ADT: 40

LOCAL

Poor

Over: SMALL STREAM

073032901, Louisa, IA

Built 1950 Load: 24.5 t ADT: 11

FM

Poor

Over: SMALL STREAM

099463002, Lyon, IA

Built 1972 Load: 24.5 t ADT: 240

LOCAL

Poor

Over: MUD CREEK

085201403, Marshall, IA

Built 1985 Load: 24.5 t ADT: 26

LOCAL

Poor

Over: MCCANDLESS CLEGHORN

084461401, Monona, IA

Built 1976 Load: 24.5 t ADT: 26

LOCAL

Poor

Over: STREAM

085420404, Monona, IA

Built 1973 Load: 24.5 t ADT: 80

FM

Poor

Over: WALNUT CREEK TRIB

071392104, Montgomery, IA

Built 1965 Load: 24.5 t ADT: 153

US 6

Poor

Over: E BR WAPSINONOC CREEK

0.5 mi. E of jct. IA 70, Muscatine, IA

Built 1920 Load: 24.5 t ADT: 1,740

Showing 19,801-19,850 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.