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

LOCAL

Fair

Over: SMALL

097112802, Chickasaw, IA

Built 1983 Load: 50.9 t ADT: 82

US 65

Fair

Over: WHITE BREAST CREEK

1.1 MI. S OF JCT. US 34, Lucas, IA

Built 1991 Load: 50.9 t ADT: 1,260

BIG SIOUX RIVER RD

Fair

Over: BIG SIOUX RIVER

0.5 MI. N OF JCT. IA 12, Plymouth, IA

Built 1996 Load: 50.9 t ADT: 1,121

LCL-DEACON ROAD

Fair

Over: PONY CREEK

072430918, Mills, IA

Built 1992 Load: 51.0 t ADT: 278

FM

Fair

Over: BRANCH YELLOW RIVER

096051305, Allamakee, IA

Built 1999 Load: 51.1 t ADT: 933

FM

Fair

Over: MUD CREEK

084110902, Benton, IA

Built 2002 Load: 51.1 t ADT: 200

210TH ST

Fair

Over: ROCK RUN CREEK

081033301, Cedar, IA

Built 2000 Load: 51.1 t ADT: 1,350

FM

Fair

Over: BR OF MIDDLE NODAWAY

076332004, Adair, IA

Built 1979 Load: 51.2 t ADT: 15

IA 14

Fair

Over: STREAM

1.0 Mi. N of S.R. C23, Butler, IA

Built 1994 Load: 51.2 t ADT: 1,740

IA 70

Fair

Over: SHORT CREEK

0.4 mi. N of Jct. IA 92, Louisa, IA

Built 1994 Load: 51.2 t ADT: 1,170

FM

Fair

Over: OVERFLW OF PILOT CREEK

092310106, Pocahontas, IA

Built 1995 Load: 51.2 t ADT: 379

FM

Fair

Over: WHITE OAK CREEK

081231603, Polk, IA

Built 1990 Load: 51.2 t ADT: 270

IA 191

Fair

Over: MOSQUITO CREEK

2.3 MI. S. OF Jct. IA #37, Shelby, IA

Built 1991 Load: 51.2 t ADT: 790

FM RD F32

Fair

Over: SMALL STREAM

080371901, Shelby, IA

Built 2008 Load: 51.2 t ADT: 60

LOCAL

Fair

Over: COON CREEK

0884222, Woodbury, IA

Built 1988 Load: 51.2 t ADT: 5

FM

Fair

Over: MCELHANEY CREEK

089430502, Woodbury, IA

Built 1973 Load: 51.2 t ADT: 748

142ND ST

Fair

Over: W BRANCH BUFFALO CR

9008277423, Buchanan, IA

Built 2011 Load: 51.3 t ADT: 47

LOCAL

Fair

Over: STREAM

088431502, Woodbury, IA

Built 1992 Load: 51.3 t ADT: 11

LOCAL

Fair

Over: D D 40

100322902, Emmet, IA

Built 1975 Load: 51.4 t ADT: 20

SB IA 13

Fair

Over: OVER CC RR

0.4 MI S OF S JCT. SR E16, Linn, IA

Built 1973 Load: 51.4 t ADT: 3,600

LOCAL

Fair

Over: TRACY CREEK

74200800, Marion, IA

Built 2009 Load: 51.4 t ADT: 80

LOCAL

Fair

Over: STREAM

100403301, Osceola, IA

Built 1957 Load: 51.4 t ADT: 11

FM

Fair

Over: SOUTH RACCOON RIVER

078272106, Dallas, IA

Built 1979 Load: 51.5 t ADT: 170

FM 280TH ST.

Fair

Over: SPRING CREEK

087100601, Buchanan, IA

Built 1952 Load: 51.6 t ADT: 246

HOWE

Fair

Over: STREAM

068222103, Wayne, IA

Built 2017 Load: 51.6 t ADT: 15

195 TH

Fair

Over: SMALL

084322305, Greene, IA

Built 1989 Load: 51.7 t ADT: 46

IA 22

Fair

Over: IOWA RIVER OVERFLOW

1.7 mi. E of Jct. US 218, Washington, IA

Built 1987 Load: 51.7 t ADT: 4,250

UNIVERSITY AVE

Fair

Over: NORTH FORK CATFISH CREEK

E. OF JOHN F KENNEDY RD, Dubuque, IA

Built 2006 Load: 51.8 t ADT: 4,131

LOCAL

Fair

Over: SMALL CREEK

098100405, Winneshiek, IA

Built 1900 Load: 51.8 t ADT: 26

LOCAL

Fair

Over: W. BR. IOWA RIVER

093240202, Wright, IA

Built 1990 Load: 51.8 t ADT: 26

SB US 218

Fair

Over: CEDAR RIVER

0.6 mi. N of Jct. SR C50, Bremer, IA

Built 1993 Load: 51.9 t ADT: 9,500

IA 25

Fair

Over: BRUSHY CREEK

3.2 MI. N OF IA 44, Guthrie, IA

Built 1980 Load: 51.9 t ADT: 1,400

US 75

Fair

Over: LITTLE ROCK RIVER

0.4 mi. S of SR A44, Lyon, IA

Built 1975 Load: 51.9 t ADT: 2,610

WB IA 141

Fair

Over: FROG CREEK

0.1 MILES W OF JCT IA 144, Dallas, IA

Built 1976 Load: 52.0 t ADT: 2,210

LOCAL

Fair

Over: DEEP CREEK

084E53103, Jackson, IA

Built 2004 Load: 52.0 t ADT: 40

216 AVE

Fair

Over: CREEK

086E30804, Jackson, IA

Built 2000 Load: 52.0 t ADT: 60

IA 92

Fair

Over: INDIAN CREEK

1.1 mi. W of Jct. SR X43, Louisa, IA

Built 1992 Load: 52.1 t ADT: 3,350

FM

Fair

Over: PRAIRIE ROSE CREEK

078372203, Shelby, IA

Built 1984 Load: 52.1 t ADT: 45

FM

Fair

Over: BUCKEYE CREEK

082122205, Benton, IA

Built 1960 Load: 52.2 t ADT: 850

LOCAL

Fair

Over: BR PRAIRIE CREEK

083122302, Benton, IA

Built 1995 Load: 52.2 t ADT: 71

SB US 218

Fair

Over: CROOKED CREEK

2.4 mi. N of Jct. IA 22, Johnson, IA

Built 1982 Load: 52.2 t ADT: 9,650

W 4TH ST

Fair

Over: WEST BR INDIAN CREEK

000000000, Story, IA

Built 1998 Load: 52.3 t ADT: 1,119

EATON AVE / E33

Fair

Over: RACCOON RIVER

084322306, Greene, IA

Built 1993 Load: 52.4 t ADT: 199

TODD HILLS RD

Fair

Over: OTTER CREEK

084082403, Linn, IA

Built 1997 Load: 52.4 t ADT: 59

IA 83

Fair

Over: WEST NISHNABOTNA RIVER

0.4 MI. E OF U.S. 59, Pottawattamie, IA

Built 1990 Load: 52.4 t ADT: 1,530

US 169

Fair

Over: WALNUT CREEK

2.1 MI. N OF N JCT. IA 2, Ringgold, IA

Built 1985 Load: 52.4 t ADT: 1,730

LOCAL

Fair

Over: CREEK

080361002, Audubon, IA

Built 1988 Load: 52.5 t ADT: 30

E MARQUIS RD

Fair

Over: CRANE CREEK

90-12-03-01-10, Black Hawk, IA

Built 2003 Load: 52.5 t ADT: 49

LOCAL 250TH ST

Fair

Over: PINE CR

088082003, Buchanan, IA

Built 2004 Load: 52.5 t ADT: 82

COUNTY RD X-44

Fair

Over: BIG BEAR CREEK

084031402, Jones, IA

Built 1978 Load: 52.5 t ADT: 619

Showing 8,651-8,700 of 20,753 bridges

Related

All states → | National rankings → | Understanding conditions → | SD bridges explained →
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.