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: DES MOINES RIVER

094310803, Palo Alto, IA

Built 1988 Load: 41.1 t ADT: 46

IDEAL ROAD

Good

Over: UNNAMED WATERWAY

9146150310, Plymouth, IA

Built 2021 Load: 41.1 t ADT: 26

FM

Good

Over: SMALL

093461101, Plymouth, IA

Built 2006 Load: 41.1 t ADT: 450

FM

Good

Over: HICORY CREEK

079E22304, Scott, IA

Built 2010 Load: 41.1 t ADT: 640

Y30 20TH AVE

Good

Over: TRIB TO MUD CREEK

080E13302, Scott, IA

Built 2021 Load: 41.1 t ADT: 460

FM

Good

Over: NO NAME CREEK

097480804, Sioux, IA

Built 1966 Load: 41.1 t ADT: 789

180TH ST

Good

Over: IOWAY CREEK

084241801, Story, IA

Built 1995 Load: 41.1 t ADT: 60

580TH AVE

Good

Over: SMALL STREAM

083233302, Story, IA

Built 1987 Load: 41.1 t ADT: 818

IA 16

Good

Over: LITTLE CEDAR CREEK

1.6 Mi. E. of SR W30, Van Buren, IA

Built 2015 Load: 41.1 t ADT: 1,070

G 26 (190TH ST)

Good

Over: UNNAMED CREEK

076082101, Washington, IA

Built 2014 Load: 41.1 t ADT: 540

LOCAL ROAD

Good

Over: COLDWATER CREEK

100102301, Winneshiek, IA

Built 1994 Load: 41.1 t ADT: 20

K64

Good

Over: DRAINAGE

088450302, Woodbury, IA

Built 2021 Load: 41.1 t ADT: 928

COUNTY HOME RD

Good

Over: STREAM

088472401, Woodbury, IA

Built 2011 Load: 41.1 t ADT: 120

IA 17

Good

Over: PRAIRIE CREEK

1.0 mi. N of Jct. SR C26, Wright, IA

Built 2022 Load: 41.1 t ADT: 1,230

SB I-380

Good

Over: BEAR CREEK

1.2 MI. S OF JCT. SR D48, Buchanan, IA

Built 1984 Load: 41.2 t ADT: 8,950

W 62

Good

Over: OLD MANS CREEK

0790736, Johnson, IA

Built 2014 Load: 41.2 t ADT: 550

US 61 NB

Good

Over: BNSF RR

1.1 mi. S of Jct. Ia. 2, Lee, IA

Built 1999 Load: 41.2 t ADT: 3,850

SB US 61

Good

Over: BNSF RR

1.1 mi. S of Jct. Ia. 2, Lee, IA

Built 1999 Load: 41.2 t ADT: 3,850

NB US 169

Good

Over: LIZARD CREEK

0.3 mi. S of IA 7, Webster, IA

Built 2010 Load: 41.2 t ADT: 4,400

IA 76

Good

Over: BLOODY RUN CREEK

0.2 MI. S OF N JCT. US 18, Clayton, IA

Built 1994 Load: 41.3 t ADT: 3,580

IA 5 SB

Good

Over: COAL CREEK

0.7 MILES NORTH OF IA 316, Warren, IA

Built 1997 Load: 41.3 t ADT: 4,300

FM

Good

Over: RUTT BRANCH

75320802, Adair, IA

Built 2009 Load: 41.4 t ADT: 319

LOCAL

Good

Over: NISHNABOTNA TRIB

072380201, Montgomery, IA

Built 2003 Load: 41.4 t ADT: 40

X6A MAYS PRAIRIE

Good

Over: FRENCH CREEK

099051106, Allamakee, IA

Built 2018 Load: 41.5 t ADT: 137

N36 PHEASANT AVE

Good

Over: DAVIDS CREEK

FM 079340302, Audubon, IA

Built 2021 Load: 41.5 t ADT: 240

FM

Good

Over: BEAVER CREEK

083282101, Boone, IA

Built 2010 Load: 41.5 t ADT: 20

V14 EASTON AVE

Good

Over: HORTON CREEK

093142302, Bremer, IA

Built 2021 Load: 41.5 t ADT: 226

IA 57

Good

Over: PHELPS CREEK

0.3 MI. E OF IA 14, Butler, IA

Built 2017 Load: 41.5 t ADT: 2,360

QUARRY AVE.

Good

Over: STREAM

092161404, Butler, IA

Built 2010 Load: 41.5 t ADT: 91

T16 (CLAY AVE)

Good

Over: BOYLAN CREEK

092180404, Butler, IA

Built 2012 Load: 41.5 t ADT: 393

RED STAR RD

Good

Over: SUGAR CREEK

080020404, Cedar, IA

Built 2021 Load: 41.5 t ADT: 71

210TH ST

Good

Over: SUGAR CR

081023301, Cedar, IA

Built 2016 Load: 41.5 t ADT: 71

340TH

Good

Over: SHELL ROCK RIVER

000000000, Cerro Gordo, IA

Built 2010 Load: 41.5 t ADT: 82

B20 300TH ST

Good

Over: SPRING CREEK

0.5 MI E US65, Cerro Gordo, IA

Built 2016 Load: 41.5 t ADT: 589

630TH ST

Good

Over: SILVER CREEK

090402201, Cherokee, IA

Built 2022 Load: 41.5 t ADT: 20

120TH STREET

Good

Over: STREAM

083E41701, Clinton, IA

Built 1959 Load: 41.5 t ADT: 30

D AVE

Good

Over: MOSQUITO CREEK

079291502, Dallas, IA

Built 2013 Load: 41.5 t ADT: 26

FM

Good

Over: BRUSH CREEK

068240501, Decatur, IA

Built 2001 Load: 41.5 t ADT: 45

A 18 140TH ST

Good

Over: LITTLE SIOUX RIVER

100343201, Dickinson, IA

Built 2022 Load: 41.5 t ADT: 81

Y17 GUN CLUB RD

Good

Over: LITTLE MAQUOKETA RIVER

089013506, Dubuque, IA

Built 2021 Load: 41.5 t ADT: 619

CHRISTOPH RD

Good

Over: NO FORK MAQUOKETA RIVER

089021904, Dubuque, IA

Built 2019 Load: 41.5 t ADT: 207

CLEAR CREEK RD

Good

Over: N FORK LITTLE MAQUKET

Clear Creek Rd, Dubuque, IA

Built 2016 Load: 41.5 t ADT: 88

JUNIPER RD

Good

Over: TURKEY RIVER

000000000, Fayette, IA

Built 2009 Load: 41.5 t ADT: 403

F 25 160TH ROAD

Good

Over: MOSQUITO CREEK

080300101, Guthrie, IA

Built 2022 Load: 41.5 t ADT: 289

LOCAL

Good

Over: DRAINAGE DITCH

087242801, Hamilton, IA

Built 2006 Load: 41.5 t ADT: 379

S57

Good

Over: HONEY CREEK

086201502, Hardin, IA

Built 2022 Load: 41.5 t ADT: 344

RR AVE

Good

Over: HONEY CREEK

086202303, Hardin, IA

Built 2011 Load: 41.5 t ADT: 29

260TH ST

Good

Over: BEAVER CREEK

087202501, Hardin, IA

Built 2019 Load: 41.5 t ADT: 91

M AVE

Good

Over: SOUTH FORK OF IOWA RIVER

087210102, Hardin, IA

Built 2021 Load: 41.5 t ADT: 47

FM

Good

Over: LITTLE BEAR CREEK

080111806, Iowa, IA

Built 2000 Load: 41.5 t ADT: 540

Showing 14,551-14,600 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.