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 190TH ST

Good

Over: MALONE CR

089092403, Buchanan, IA

Built 2004 Load: 31.8 t ADT: 21

US 71

Good

Over: STREAM

2.2 mi. S of IA 3, Buena Vista, IA

Built 1996 Load: 31.8 t ADT: 3,000

325TH ST

Good

Over: LITTLE ELKHORN CREEK

079012803, Cedar, IA

Built 2011 Load: 31.8 t ADT: 35

WASHINGTON AVE

Good

Over: SMALL STREAM

080011402, Cedar, IA

Built 2017 Load: 31.8 t ADT: 34

HAYES AVE

Good

Over: ROCK RUN CR

081030806, Cedar, IA

Built 2008 Load: 31.8 t ADT: 26

FM

Good

Over: HOCKETT CREEK

083371702, Crawford, IA

Built 1980 Load: 31.8 t ADT: 170

170TH ST

Good

Over: CHEQUEST CREEK

069140201, Davis, IA

Built 2021 Load: 31.8 t ADT: 30

LOCAL

Good

Over: HICKORY CREEK

089021503, Dubuque, IA

Built 1984 Load: 31.8 t ADT: 59

LOCAL

Good

Over: STREAM

074111005, Keokuk, IA

Built 1990 Load: 31.8 t ADT: 11

LOCAL

Good

Over: SMALL STREAM

073041901, Louisa, IA

Built 1986 Load: 31.8 t ADT: 30

FAS MAJOR B-40

Good

Over: ROETZEL CREEK

095420801, O'Brien, IA

Built 2006 Load: 31.8 t ADT: 828

FM

Good

Over: MUDDY CREEK

090453303, Plymouth, IA

Built 1985 Load: 31.8 t ADT: 559

FM

Good

Over: RATHBUN CREEK

091431901, Plymouth, IA

Built 1986 Load: 31.8 t ADT: 150

HEDGE AVE

Good

Over: SMALL CREEK

9347250210, Plymouth, IA

Built 2020 Load: 31.8 t ADT: 15

IA 10

Good

Over: NORTH LIZARD CREEK

1.6 mi. W of Jct IA 4, Pocahontas, IA

Built 2003 Load: 31.8 t ADT: 1,200

FM

Good

Over: BIG CEDAR CK DD #181

091342401, Pocahontas, IA

Built 1980 Load: 31.8 t ADT: 11

LOCAL

Good

Over: DD #77 NO LIZARD CK

092321602, Pocahontas, IA

Built 1984 Load: 31.8 t ADT: 20

LOCAL

Good

Over: PILOT CREEK

093313102, Pocahontas, IA

Built 1984 Load: 31.8 t ADT: 34

SB I 35

Good

Over: CLANTON CREEK

2.3 MILES S OF JCT IA 92, Warren, IA

Built 2007 Load: 31.8 t ADT: 11,400

IA 22

Good

Over: DRAINAGE DITCH

0.8 mi. W of jct. US 218, Washington, IA

Built 1988 Load: 31.8 t ADT: 6,200

210TH ST.

Good

Over: STREAM

082E63201, Clinton, IA

Built 1958 Load: 31.9 t ADT: 70

PEACH AVE

Good

Over: HICKORY BRANCH

067131502, Davis, IA

Built 2019 Load: 31.9 t ADT: 11

250TH ST

Good

Over: SMALL STREAM

068151401, Davis, IA

Built 2019 Load: 31.9 t ADT: 30

SPENCER AVE

Good

Over: PIGEON CREEK

078421004, Harrison, IA

Built 2008 Load: 31.9 t ADT: 45

200TH ST

Good

Over: SMALL STREAM

092492501, Plymouth, IA

Built 1986 Load: 31.9 t ADT: 40

LOCAL

Good

Over: WINNEBAGO RIVER

098223608, Worth, IA

Built 1975 Load: 31.9 t ADT: 30

130TH ST

Good

Over: CREEK

081341901 LOCAL RD, Audubon, IA

Built 2018 Load: 32.0 t ADT: 5

LOCAL

Good

Over: COAL CREEK

076212808, Marion, IA

Built 2005 Load: 32.0 t ADT: 21

380TH

Good

Over: SHELLROCK RIVER

098201303, Worth, IA

Built 1962 Load: 32.0 t ADT: 35

US 18 & 52

Good

Over: NATURAL STREAM

0.6 MI. W OF E JCT. US 52, Clayton, IA

Built 1967 Load: 32.1 t ADT: 3,780

278TH ST

Good

Over: BARBER CREEK

081E33305, Clinton, IA

Built 2017 Load: 32.1 t ADT: 41

P 58 (J AVE)

Good

Over: N RACCOON RIVER

081283404, Dallas, IA

Built 2012 Load: 32.1 t ADT: 1,454

HIDDEN VALLEY LANE

Good

Over: STREAM

08802E2506, Dubuque, IA

Built 2021 Load: 32.1 t ADT: 128

US 275

Good

Over: NISHNABOTNA RIVER

0.5 mi W of E JCT. IA 333, Fremont, IA

Built 1994 Load: 32.1 t ADT: 1,160

N 73RD AVE W

Good

Over: SMALL STREAM

081203403, Jasper, IA

Built 2015 Load: 32.1 t ADT: 35

190TH AVE

Good

Over: BR WHITE BREAST CREEK

073222202, Lucas, IA

Built 2021 Load: 32.1 t ADT: 5

E 140TH ST S

Good

Over: SMALL STREAM

079171102, Jasper, IA

Built 2002 Load: 32.2 t ADT: 21

LOCAL

Good

Over: SMALL STREAM

081190603, Jasper, IA

Built 2000 Load: 32.2 t ADT: 11

EAGLE AVE

Good

Over: CLEAR CREEK

080082308, Johnson, IA

Built 1993 Load: 32.2 t ADT: 15

IA 8

Good

Over: COON CREEK

0.5 MILE EAST OF US 63, Tama, IA

Built 1989 Load: 32.2 t ADT: 1,950

IA 2

Good

Over: HONEY CREEK

2.9 MI. E OF SR N44, Taylor, IA

Built 1976 Load: 32.2 t ADT: 1,390

NB US 218

Good

Over: ENGLISH RIVER

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

Built 1994 Load: 32.2 t ADT: 7,450

WAGNER RD

Good

Over: TRIB TO CEDAR RIVER

90-13-22-02-10, Black Hawk, IA

Built 1974 Load: 32.3 t ADT: 933

IA 3

Good

Over: BASKINS CREEK

2.6 MI. W OF JCT. U.S. 63, Bremer, IA

Built 1996 Load: 32.3 t ADT: 4,160

US 71

Good

Over: MIDDLE RACCOON RIVER

0.7 mi. S of US 30, Carroll, IA

Built 1985 Load: 32.3 t ADT: 5,100

NETTLE

Good

Over: E BR BEAVER DAM CREEK

095202002, Cerro Gordo, IA

Built 1993 Load: 32.3 t ADT: 30

PHEASANT

Good

Over: E BR BEAVER DAM CREEK

095203404, Cerro Gordo, IA

Built 1983 Load: 32.3 t ADT: 334

320TH

Good

Over: SPRING CREEK

097201603, Cerro Gordo, IA

Built 1984 Load: 32.3 t ADT: 47

MISSISSIPPI RD

Good

Over: STREAM

093021803, Clayton, IA

Built 2005 Load: 32.3 t ADT: 157

A AVE

Good

Over: DEEP CREEK

093063104, Clayton, IA

Built 1998 Load: 32.3 t ADT: 11

Showing 10,301-10,350 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.