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

Good

Over: COON CREEK

083392104, Crawford, IA

Built 1958 Load: 18.1 t ADT: 89

W AVE

Good

Over: SNAKE CREEK

082291406, Greene, IA

Built 1982 Load: 18.1 t ADT: 41

US 30

Good

Over: STREAM

1.5 MI. W OF IA 37, Harrison, IA

Built 1924 Load: 18.1 t ADT: 3,090

LOCAL

Good

Over: SMALL STREAM

081200101, Jasper, IA

Built 1997 Load: 18.1 t ADT: 16

LOCAL

Good

Over: STREAM

077130101, Keokuk, IA

Built 1999 Load: 18.1 t ADT: 15

US 169

Good

Over: DRAINAGE

0.8 mi. S of SR B14, Kossuth, IA

Built 1959 Load: 18.1 t ADT: 2,140

US 34

Good

Over: CITY RESERVOIR INLET

1.8 mi. E of Jct. IA #14, Lucas, IA

Built 1958 Load: 18.1 t ADT: 3,080

LOCAL

Good

Over: STREAM

074180606, Marion, IA

Built 2003 Load: 18.1 t ADT: 5

IA 175

Good

Over: DRAINAGE DITCH

3.8 mi. W of SR L37, Monona, IA

Built 1900 Load: 18.1 t ADT: 1,430

IA 175

Good

Over: STREAM

2.9 mi E of W Jct IA 141, Monona, IA

Built 1952 Load: 18.1 t ADT: 1,430

IA 92

Good

Over: STREAM

0.4 mi. W of Jct. SR M16, Pottawattamie, IA

Built 1955 Load: 18.1 t ADT: 2,920

US 30

Good

Over: RICHARDS CREEK

0.1 MILE EAST OF JCT I-35, Story, IA

Built 1963 Load: 18.1 t ADT: 14,000

DUNN STREET

Good

Over: DRAINAGE DITCH #70

Dunn Street, Story, IA

Built 1969 Load: 18.1 t ADT: 170

IA 139

Good

Over: ELLIOT CREEK

1.5 MI. N OF SR A18, Winneshiek, IA

Built 1954 Load: 18.1 t ADT: 830

FM

Good

Over: TROUT RIVER

098073404, Winneshiek, IA

Built 1967 Load: 18.1 t ADT: 50

FM

Good

Over: CANOE CREEK

099082104, Winneshiek, IA

Built 1959 Load: 18.1 t ADT: 580

FM

Good

Over: CREEK

100101301, Winneshiek, IA

Built 1967 Load: 18.1 t ADT: 45

20TH ST

Good

Over: IAIS RR

080161702, Poweshiek, IA

Built 2018 Load: 18.2 t ADT: 200

300TH AVE

Good

Over: LOTTS CREEK

069282102, Ringgold, IA

Built 2013 Load: 18.2 t ADT: 5

LOCAL

Good

Over: TWELVE MILE CREEK

071283603, Union, IA

Built 1992 Load: 18.2 t ADT: 15

US 30

Good

Over: STREAM

1.6 MILES E OF E JCT T47, Tama, IA

Built 1996 Load: 18.3 t ADT: 11,500

SCOTT BLVD

Good

Over: SMALL STREAM

087080104, Buchanan, IA

Built 2014 Load: 18.4 t ADT: 51

170TH ST

Good

Over: PRAIRIE CREEK

089070801, Buchanan, IA

Built 2014 Load: 18.4 t ADT: 44

LOCAL ROAD

Good

Over: CREEK

079230401, Polk, IA

Built 2003 Load: 18.4 t ADT: 60

190TH ST

Good

Over: WESTFIELD CREEK

092482001, Plymouth, IA

Built 1990 Load: 18.5 t ADT: 20

LOCAL 250TH ST

Good

Over: SMALL STREAM

088082301, Buchanan, IA

Built 2010 Load: 18.6 t ADT: 98

PHEASANT RD

Good

Over: BASS CREEK

095090405, Fayette, IA

Built 1950 Load: 18.6 t ADT: 49

LOCAL

Good

Over: BEAVER CREEK

085400802, Crawford, IA

Built 1975 Load: 18.8 t ADT: 30

LOCAL

Good

Over: SUGAR CREEK

067050503, Lee, IA

Built 1978 Load: 18.8 t ADT: 131

420TH ST

Good

Over: BARRY CREEK

095 39 20 01, O'Brien, IA

Built 2011 Load: 18.8 t ADT: 71

LOCAL

Good

Over: LITTLE OCHEYDAN RIVER

099411201, Osceola, IA

Built 1966 Load: 18.8 t ADT: 41

FM

Good

Over: STREAM

080222706, Polk, IA

Built 1975 Load: 18.8 t ADT: 417

JUNIPER ROAD

Good

Over: SILVER CREEK

076413601, Pottawattamie, IA

Built 1984 Load: 18.8 t ADT: 40

LOCAL

Good

Over: CREEK

096083301, Winneshiek, IA

Built 1985 Load: 18.8 t ADT: 70

HAZEL RD

Good

Over: MOSER CREEK

081392102, Shelby, IA

Built 2013 Load: 18.9 t ADT: 41

LOCAL

Good

Over: FIELD STREAM

082332902, Carroll, IA

Built 1995 Load: 19.0 t ADT: 20

DELTA AVE

Good

Over: BALDWIN CREEK

081042202, Cedar, IA

Built 2014 Load: 19.0 t ADT: 70

LOCAL

Good

Over: BEAVER CREEK

085401203, Crawford, IA

Built 2006 Load: 19.0 t ADT: 11

405TH

Good

Over: LITTLE CEDAR RIVER

099163503, Mitchell, IA

Built 1974 Load: 19.0 t ADT: 29

LOCAL

Good

Over: CREEK

069340302, Taylor, IA

Built 2007 Load: 19.0 t ADT: 15

LOCAL

Good

Over: CREEK

000000000, Dubuque, IA

Built 2009 Load: 19.1 t ADT: 900

LOCAL ROAD

Good

Over: DICKEY BR.

070060105, Henry, IA

Built 2007 Load: 19.1 t ADT: 11

LOCAL

Good

Over: SMALL CREEK

096090704, Winneshiek, IA

Built 1979 Load: 19.1 t ADT: 59

ORANGE RD

Good

Over: TURKEY RIVER

095090206, Fayette, IA

Built 2005 Load: 19.2 t ADT: 39

PHEASANT RD

Good

Over: TURKEY RIVER

095090305, Fayette, IA

Built 2004 Load: 19.2 t ADT: 44

LOCAL

Good

Over: LITTLE TURKEY RIVER

095092603, Fayette, IA

Built 1996 Load: 19.2 t ADT: 29

SILVER AVE

Good

Over: SMALL STREAM

091151906, Butler, IA

Built 2013 Load: 19.3 t ADT: 11

LOCAL

Good

Over: SMALL STREAM

091170302, Butler, IA

Built 2016 Load: 19.3 t ADT: 30

LOCAL

Good

Over: BRUSHY FORK CREEK

082342204, Carroll, IA

Built 1971 Load: 19.3 t ADT: 45

LOCAL

Good

Over: TRIB S WYACONHAH DITCH

067131118, Davis, IA

Built 2002 Load: 19.3 t ADT: 40

Showing 9,101-9,150 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.