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

MIDWAY AVE

Good

Over: STREAM

093121802, Bremer, IA

Built 2012 Load: 33.8 t ADT: 88

LOCAL

Good

Over: BR RACOON RIVER

092361801, Buena Vista, IA

Built 2010 Load: 33.8 t ADT: 15

IA 24

Good

Over: CRANE CREEK

0.2 mi. E of W Jct SR V56, Chickasaw, IA

Built 2006 Load: 33.8 t ADT: 2,690

150TH AVE

Good

Over: STREAM

096382402, Clay, IA

Built 2000 Load: 33.8 t ADT: 62

205TH ST.

Good

Over: STREAM

082e42703, Clinton, IA

Built 1981 Load: 33.8 t ADT: 35

WB US 20

Good

Over: OVER ABANDON RR

0.4 mi. W of Jct. IA 38, Delaware, IA

Built 1973 Load: 33.8 t ADT: 4,250

270TH STREET

Good

Over: UNNAMED STREAM

083303101, Greene, IA

Built 2004 Load: 33.8 t ADT: 40

LOCAL

Good

Over: STREAM

000000000, Guthrie, IA

Built 2010 Load: 33.8 t ADT: 40

SB US 218

Good

Over: OLD MAN CREEK

0.7 mi. S of Jct. SR F62, Johnson, IA

Built 1982 Load: 33.8 t ADT: 9,650

LOC 60TH AVE

Good

Over: LOTTS CREEK

094302502, Kossuth, IA

Built 1986 Load: 33.8 t ADT: 72

US 63

Good

Over: UP RR

1.8 MI. N OF JCT. SR T65, Mahaska, IA

Built 2008 Load: 33.8 t ADT: 3,250

FM

Good

Over: OCHEYEDAN RIVER

097391201, O'Brien, IA

Built 1979 Load: 33.8 t ADT: 20

LOCAL

Good

Over: DRAINAGE DIST.#42

098411102, Osceola, IA

Built 2008 Load: 33.8 t ADT: 21

TANGLEWOOD RD

Good

Over: CROW CREEK

Bettendorf, IA, Scott, IA

Built 2010 Load: 33.8 t ADT: 40

508TH ST

Good

Over: STREAM

069172903, Appanoose, IA

Built 2020 Load: 33.9 t ADT: 73

LOCAL

Good

Over: BEAMAN CREEK

085360701, Carroll, IA

Built 2007 Load: 33.9 t ADT: 60

190TH STREET

Good

Over: CREEK

082E31901, Clinton, IA

Built 1949 Load: 33.9 t ADT: 490

185TH AVE

Good

Over: SMALL STREAM

083E22104, Clinton, IA

Built 1981 Load: 33.9 t ADT: 260

125TH ST.

Good

Over: ELK RIVER

083E61701, Clinton, IA

Built 2005 Load: 33.9 t ADT: 41

410TH AVE.

Good

Over: CREEK

083E61702, Clinton, IA

Built 2001 Load: 33.9 t ADT: 35

LOCAL

Good

Over: BEAVER CREEK

085411203, Crawford, IA

Built 2008 Load: 33.9 t ADT: 30

FM

Good

Over: FLINT RIVER

070021910, Des Moines, IA

Built 2000 Load: 33.9 t ADT: 780

SW HAZLWOOD AVE

Good

Over: OLD MANS CREEK

079073106, Johnson, IA

Built 1991 Load: 33.9 t ADT: 70

CALKINS AVE

Good

Over: OLD MANS CREEK

079083304, Johnson, IA

Built 1999 Load: 33.9 t ADT: 30

LOC 165TH AVE

Good

Over: LINDNER CREEK

096280304, Kossuth, IA

Built 1991 Load: 33.9 t ADT: 21

29TH AVE

Good

Over: INDIAN CREEK

084063100, Linn, IA

Built 2008 Load: 33.9 t ADT: 7,094

LOCAL RD

Good

Over: NORTH RIVER

076260904, Madison, IA

Built 2008 Load: 33.9 t ADT: 45

IA 60 SB

Good

Over: OTTER CREEK

2.0 mi. S of SR A22, Osceola, IA

Built 2006 Load: 33.9 t ADT: 2,055

IA 60 NB

Good

Over: OTTER CREEK

2.0 mi. S of SR A22, Osceola, IA

Built 2006 Load: 33.9 t ADT: 2,055

BLUEBIRD AVE

Good

Over: LOCAL

092483002, Plymouth, IA

Built 1986 Load: 33.9 t ADT: 34

LOCAL

Good

Over: UPPER IOWA RIVER

000053511, Allamakee, IA

Built 2004 Load: 34.0 t ADT: 690

E 44 (70TH ST)

Good

Over: PRAIRIE CREEK

083111501, Benton, IA

Built 2013 Load: 34.0 t ADT: 1,070

E24 59 ST TRAIL

Good

Over: SPRING CREEK

085092407, Benton, IA

Built 2022 Load: 34.0 t ADT: 638

E24 61ST ST LN

Good

Over: SPRING CREEK

085093601, Benton, IA

Built 2015 Load: 34.0 t ADT: 177

180TH ST

Good

Over: CREEK

092121701, Bremer, IA

Built 2015 Load: 34.0 t ADT: 49

CEDAR RIVER PKWY

Good

Over: CEDAR RIVER

000000000, Bremer, IA

Built 2019 Load: 34.0 t ADT: 144

M44 105TH AVE

Good

Over: POOR FARM CREEK

091372704, Buena Vista, IA

Built 2017 Load: 34.0 t ADT: 2,414

LIBERTY AVE

Good

Over: SMALL STREAM

091171301, Butler, IA

Built 2016 Load: 34.0 t ADT: 25

310TH ST

Good

Over: STREAM

24000 block of 310th St., Cerro Gordo, IA

Built 2021 Load: 34.0 t ADT: 15

C AVE

Good

Over: FIDDLE CREEK

092421602, Cherokee, IA

Built 2023 Load: 34.0 t ADT: 71

210TH ST.

Good

Over: AMES CREEK

00000, Clinton, IA

Built 2011 Load: 34.0 t ADT: 123

340TH AVE.

Good

Over: SMALL STREAM

082E51901, Clinton, IA

Built 1990 Load: 34.0 t ADT: 73

245TH ST

Good

Over: STREAM

068151003, Davis, IA

Built 2021 Load: 34.0 t ADT: 45

V17 HILL BLVD

Good

Over: SMALL STREAM

070141804, Davis, IA

Built 2018 Load: 34.0 t ADT: 160

FALCON BLVD

Good

Over: SMALL STREAM

070152402, Davis, IA

Built 2019 Load: 34.0 t ADT: 50

FM 272ND ST

Good

Over: N FORK MAQUOKETA RIVER

088033605, Delaware, IA

Built 1999 Load: 34.0 t ADT: 462

FM 220 AVE

Good

Over: MAQUOKETA RIVER

088043004, Delaware, IA

Built 2008 Load: 34.0 t ADT: 894

Y AVE

Good

Over: SMALL STREAM

094103102, Fayette, IA

Built 2022 Load: 34.0 t ADT: 20

PIONEER AVE

Good

Over: SILVER CREEK

088390202, Ida, IA

Built 2018 Load: 34.0 t ADT: 11

LOCAL

Good

Over: SILVER CREEK

089401501, Ida, IA

Built 2003 Load: 34.0 t ADT: 62

Showing 12,551-12,600 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.