State profile · Above national median SD

Iowa bridge safety

Condition ratings, load ratings, and structural-deficiency data for every public highway bridge in Iowa — drawn straight from the FHWA National Bridge Inventory.

20,753
Public bridges
36.5%
Good condition
20.0%
Poor condition
20.0%
Structurally deficient

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 rated 0-4

Structurally Deficient

20.0%

4,153 bridges flagged for repair priority

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 — Structurally deficient share 66.7%
National avg

Lower is better. Bar maxes at 30% (worst-state ceiling). National average sits at 7.0%.

Condition Distribution

Bridge inventory deck-condition mix — Iowa (FHWA NBI)

Iowa36.534476943092564%38.39444899532597%20.011564593070883%20.011564593070883%GoodFairPoorStructurally Deficient
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 on the structurally deficient leaderboard (lower share = better)

States are ranked by share of bridges flagged structurally deficient — the FHWA classification for any span where deck, superstructure, or substructure carries a condition rating of 4 or below. Lower percentages indicate stronger maintenance funding and inspection follow-through. States here sit immediately above and below Iowa on the same metric.

54

West Virginia

16.02% top marginal rate
Structure
Progressive
Burden @ $100K
$7,679

46

South Dakota

16.24% top marginal rate
Structure
Progressive
Burden @ $100K
$5,905
Selected

19

Iowa

20.01% top marginal rate
Structure
Progressive
Burden @ $100K
$20,753

78

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 composite NBI rating. Each is inspected at least every 24 months.

270TH STREET

Structurally Deficient

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

Structurally Deficient

Over: MUD CREEK

87-12-15-02-10, Black Hawk, IA

Built 1948 Load: 2.7 t ADT: 11

LOCAL - 700TH

Structurally Deficient

Over: TRIB TROUBLESOME CREEK

077351402, Cass, IA

Built 1983 Load: 2.7 t ADT: 11

LOCAL - DAYTONA

Structurally Deficient

Over: BUCK CREEK

077361903, Cass, IA

Built 1980 Load: 2.7 t ADT: 35

100TH ST.

Structurally Deficient

Over: UNION CREEK

083E20101, Clinton, IA

Built 1900 Load: 2.7 t ADT: 78

All Bridges in Iowa

FM

Fair

Over: CREEK

088201206, Hardin, IA

Built 1988 Load: 35.0 t ADT: 104

F20 220TH TRL

Fair

Over: PRICE CREEK

081092609, Iowa, IA

Built 1978 Load: 35.0 t ADT: 450

FM

Fair

Over: SMALL STREAM

085E22403, Jackson, IA

Built 1998 Load: 35.0 t ADT: 630

RUSTY WALACE DR

Fair

Over: SMALL STREAM

000000000, Jasper, IA

Built 1998 Load: 35.0 t ADT: 600

SE SIOUX AVE

Fair

Over: CROOKED CREEK

078053102, Johnson, IA

Built 1992 Load: 35.0 t ADT: 40

LOCAL

Fair

Over: SMALL STREAM

074051402, Louisa, IA

Built 1982 Load: 35.0 t ADT: 30

LOCAL

Fair

Over: SMALL STREAM

074052501, Louisa, IA

Built 1986 Load: 35.0 t ADT: 26

FM-HUTCHINGS AV

Fair

Over: RAINES BRANCH

072411001, Mills, IA

Built 1954 Load: 35.0 t ADT: 45

V AVENUE

Fair

Over: BUCHANAN CREEK

067361506, Page, IA

Built 1975 Load: 35.0 t ADT: 50

WISCONSIN AVE

Fair

Over: CARDINAL CREEK

000000000, Scott, IA

Built 1960 Load: 35.0 t ADT: 930

NB US 61

Fair

Over: WAPSIPINICON RIVER

2.4 mi. N of SR F33, Scott, IA

Built 1981 Load: 35.0 t ADT: 8,800

LOCAL

Fair

Over: SMALL

096460701, Sioux, IA

Built 1954 Load: 35.0 t ADT: 110

LOCAL

Fair

Over: TRIB CONQUEST CREEK

069111403, Van Buren, IA

Built 2004 Load: 35.0 t ADT: 5

SB US 218

Fair

Over: GOOSE CREEK

6.6 MI. N OF JCT. IA 92, Washington, IA

Built 1984 Load: 35.0 t ADT: 7,450

US 218 SB

Fair

Over: ENGLISH RIVER

0.6 MI. S OF JCT. IA 22, Washington, IA

Built 1984 Load: 35.0 t ADT: 7,450

FM

Fair

Over: WONDER CREEK

097102305, Winneshiek, IA

Built 1970 Load: 35.0 t ADT: 88

LOCAL

Fair

Over: SMALL CREEK

098091602, Winneshiek, IA

Built 1985 Load: 35.0 t ADT: 20

YANKEE AVE

Fair

Over: DD #29

090232305, Wright, IA

Built 1978 Load: 35.0 t ADT: 35

LOCAL

Fair

Over: DD #29

090232304, Wright, IA

Built 1978 Load: 35.0 t ADT: 35

SB 218,EB 57

Fair

Over: CEDAR RIVER OVERFLOW

0.2 mi. E of jct. IA 27, Black Hawk, IA

Built 1974 Load: 35.1 t ADT: 9,800

LOCAL

Fair

Over: CREEK

088010902, Dubuque, IA

Built 1900 Load: 35.1 t ADT: 49

LOCAL

Fair

Over: STREAM

080310901, Guthrie, IA

Built 1968 Load: 35.1 t ADT: 50

FM

Fair

Over: DRAINAGE DITCH

091292101, Humboldt, IA

Built 1958 Load: 35.1 t ADT: 170

US 34

Fair

Over: LITTLE TARKIO CREEK

0.2 MI. E of SR M63, Montgomery, IA

Built 1964 Load: 35.1 t ADT: 2,880

IA 48

Fair

Over: OVERFLOW NISHNABOTNA

2.0 mi. S of Jct. SR H14, Montgomery, IA

Built 1973 Load: 35.1 t ADT: 1,210

SB I-35

Fair

Over: OVER UPP RR

1.1 MILES N OF N JCT I-80, Polk, IA

Built 2002 Load: 35.1 t ADT: 45,700

FM

Fair

Over: STREAM

079131707, Poweshiek, IA

Built 1975 Load: 35.1 t ADT: 20

FM

Fair

Over: WILLOW CREEK

811439, Shelby, IA

Built 1969 Load: 35.1 t ADT: 887

670TH AVE

Fair

Over: EAST INDIAN CREEK

084221202, Story, IA

Built 1915 Load: 35.1 t ADT: 26

LOCAL

Fair

Over: STREAM

071290701, Union, IA

Built 1965 Load: 35.1 t ADT: 46

IA 2

Fair

Over: JACKSON CREEK

3.8 MI. W OF Jct. SR S56, Wayne, IA

Built 1962 Load: 35.1 t ADT: 2,160

LOCAL

Fair

Over: CALEB CREEK

068230301, Wayne, IA

Built 1993 Load: 35.1 t ADT: 15

DYSART RD

Fair

Over: TRIB TO MILLER CREEK

88-12-19-04-10, Black Hawk, IA

Built 1981 Load: 35.2 t ADT: 1,463

FM

Fair

Over: HICKORY CREEK

067130506, Davis, IA

Built 1976 Load: 35.2 t ADT: 290

LOC 60TH AVE

Fair

Over: PRAIRIE CREEK

098301202, Kossuth, IA

Built 1990 Load: 35.2 t ADT: 41

IA 25

Fair

Over: STREAM

2.3 MI. N OF N JCT SR J23, Ringgold, IA

Built 1934 Load: 35.2 t ADT: 1,250

OLD STAGE RD

Fair

Over: CREEK

098082407, Winneshiek, IA

Built 2001 Load: 35.2 t ADT: 1,051

LOCAL

Fair

Over: BRANCH WATERLOO CREEK

100061306, Allamakee, IA

Built 1960 Load: 35.3 t ADT: 39

LOCAL

Fair

Over: CREEK

078360603, Audubon, IA

Built 1973 Load: 35.3 t ADT: 51

FM 260TH AVE

Fair

Over: MONTGOMERY CREEK

094360202, Clay, IA

Built 1978 Load: 35.3 t ADT: 71

160TH ST.

Fair

Over: DD #12

082E20501, Clinton, IA

Built 1979 Load: 35.3 t ADT: 35

175TH ST

Fair

Over: DRAINAGE DITCH #12

082E21105, Clinton, IA

Built 1980 Load: 35.3 t ADT: 16

IA 13

Fair

Over: BRANCH MAQUOKETA RIVER

0.9 mi N of N jct. SR D47, Delaware, IA

Built 1975 Load: 35.3 t ADT: 4,840

OLD MILL RD

Fair

Over: CATFISH CREEK

N.W. OF ROCKDALE RD, Dubuque, IA

Built 1978 Load: 35.3 t ADT: 5,395

FM

Fair

Over: BIG CREEK

071060603, Henry, IA

Built 1992 Load: 35.3 t ADT: 540

SW HAZELWOOD AV

Fair

Over: STREAM

078070804, Johnson, IA

Built 1966 Load: 35.3 t ADT: 72

LOCAL

Fair

Over: STREAM

080061204, Johnson, IA

Built 1972 Load: 35.3 t ADT: 153

SWAN LAKE RD NE

Fair

Over: STREAM

080070503, Johnson, IA

Built 1973 Load: 35.3 t ADT: 100

MILITARY RD

Fair

Over: BR KITTY CREEK

086033306, Jones, IA

Built 1936 Load: 35.3 t ADT: 62

FM

Fair

Over: NISHNABOTNA TRIB

073381304, Montgomery, IA

Built 1957 Load: 35.3 t ADT: 34

Showing 7,551-7,600 of 20,753 bridges

Related

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Data sourced from the FHWA National Bridge Inventory (NBI), latest released cycle. See our methodology for details. Retrieved and formatted by PlainBridges Editorial.

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). A "structurally deficient" rating is a repair-priority signal, not a closure or unsafe-to-cross designation. Consult a qualified civil engineer before making decisions based on this data.

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.