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

A26 BEARCREEKDR

Good

Over: BEAR CREEK

099060405, Allamakee, IA

Built 2012 Load: 46.0 t ADT: 310

LOC QUINN AVE

Good

Over: BUFFALO CR EAST BRANCH

090080202, Buchanan, IA

Built 2010 Load: 46.0 t ADT: 16

IA 14

Good

Over: COLD WATER CREEK

1.2 MILES SOUTH OF SR C13, Butler, IA

Built 2010 Load: 46.0 t ADT: 1,740

LOCAL

Good

Over: FIELD STREAM

082332201, Carroll, IA

Built 2002 Load: 46.0 t ADT: 71

LOCAL

Good

Over: STORM CREEK

085343002, Carroll, IA

Built 1987 Load: 46.0 t ADT: 79

TAYLOR AVE

Good

Over: YANKEE RUN CREEK

082012904, Cedar, IA

Built 2018 Load: 46.0 t ADT: 90

EB US 18

Good

Over: UPRR

0.7 mi. E of Jct. US 65, Cerro Gordo, IA

Built 1999 Load: 46.0 t ADT: 5,250

270TH ST

Good

Over: SILVER CREEK

000000000, Clinton, IA

Built 2009 Load: 46.0 t ADT: 220

J 66

Good

Over: STREAM

067251812, Decatur, IA

Built 2013 Load: 46.0 t ADT: 329

297TH ST

Good

Over: BUCK CREEK

087051206, Delaware, IA

Built 1999 Load: 46.0 t ADT: 15

H38 MEDIAPOLIS RD

Good

Over: CEDAR FORK

072033101, Des Moines, IA

Built 2020 Load: 46.0 t ADT: 1,080

N BANKSTON RD

Good

Over: UNNAMED STREAM

089021203, Dubuque, IA

Built 2022 Load: 46.0 t ADT: 88

B55 170TH ST

Good

Over: E FORK DES MOINES RIVER

095283101, Kossuth, IA

Built 2022 Load: 46.0 t ADT: 350

CO HOME RD

Good

Over: BIG CREEK

084051801, Linn, IA

Built 2006 Load: 46.0 t ADT: 1,935

CO HOME RD

Good

Over: DRY CREEK

Cty Home Rd over Dry Cr, Linn, IA

Built 2010 Load: 46.0 t ADT: 6,285

GRANITE AVE

Good

Over: BULL RUN

9247150210, Plymouth, IA

Built 2019 Load: 46.0 t ADT: 26

S.W.3RD ST

Good

Over: RACCOON RIVER

078240900, Polk, IA

Built 1995 Load: 46.0 t ADT: 8,948

115TH ST

Good

Over: TRIB TO SAND CREEK

070281003, Ringgold, IA

Built 2021 Load: 46.0 t ADT: 11

HICKORY AVE

Good

Over: SMITH CREEK

077081708, Washington, IA

Built 2011 Load: 46.0 t ADT: 190

IA 140

Good

Over: STREAM

4.5 mi. N of US 20, Woodbury, IA

Built 2003 Load: 46.0 t ADT: 1,930

FM

Good

Over: EAST SOLDIER

84401002, Crawford, IA

Built 2009 Load: 46.1 t ADT: 11

IA 13

Good

Over: MAQUOKETA RIVER

0.8 mi. E of W Jct SR D22, Delaware, IA

Built 1991 Load: 46.1 t ADT: 7,900

243 RD

Good

Over: HARDIN CREEK

083301405, Greene, IA

Built 2009 Load: 46.1 t ADT: 26

FM

Good

Over: GERMAN CREEK

000000000, Keokuk, IA

Built 2009 Load: 46.1 t ADT: 25

US 6

Good

Over: MIDDLE SILVER CREEK

1.2 MI. E OF SR L-55, Pottawattamie, IA

Built 1989 Load: 46.1 t ADT: 2,770

GILBERT DR

Good

Over: ELK RUN CREEK

000000000, Black Hawk, IA

Built 1983 Load: 46.2 t ADT: 2,008

FM

Good

Over: SALT CREEK

083131501, Tama, IA

Built 1998 Load: 46.2 t ADT: 226

INDIAN AVE

Good

Over: STREAM

0.1 mi S of 280 on Indian, Adair, IA

Built 2015 Load: 46.3 t ADT: 11

FM

Good

Over: WILDCAT CREEK

083100601, Benton, IA

Built 1998 Load: 46.3 t ADT: 15

200 AVE

Good

Over: OCHEYEDAN RIVER

096371502, Clay, IA

Built 2012 Load: 46.3 t ADT: 2,273

KEYSTONE RD

Good

Over: SNY MAGILL

094032202, Clayton, IA

Built 2017 Load: 46.3 t ADT: 62

LOCAL

Good

Over: MERCER CREEK

078281203, Dallas, IA

Built 1974 Load: 46.3 t ADT: 62

HERBER RD

Good

Over: LITTLE MAQUOKETA RIVER

090E22604, Dubuque, IA

Built 2015 Load: 46.3 t ADT: 1,908

SB US 61 RAMP

Good

Over: VACANT LOTS

0.5 Miles N. of Ia. # 3, Dubuque, IA

Built 1991 Load: 46.3 t ADT: 3,820

FM

Good

Over: BRUSH CREEK

070412702, Fremont, IA

Built 1993 Load: 46.3 t ADT: 468

FM

Good

Over: SMALL STREAM

074053401, Louisa, IA

Built 1950 Load: 46.3 t ADT: 690

10TH AVE

Good

Over: SMALL STREAM

075210604, Marion, IA

Built 2015 Load: 46.3 t ADT: 11

F58 (HWY 927)

Good

Over: MUD CREEK

078010401, Muscatine, IA

Built 2013 Load: 46.3 t ADT: 3,100

LOCAL

Good

Over: JORDAN CREEK

095393303, O'Brien, IA

Built 1995 Load: 46.3 t ADT: 35

120TH ST

Good

Over: TRIB DESMOINES RIVER

070111703, Van Buren, IA

Built 2019 Load: 46.3 t ADT: 35

LOCAL

Good

Over: CREEK

084E21706, Jackson, IA

Built 2007 Load: 46.5 t ADT: 59

310 TH

Good

Over: GREENBRIER CREEK

082301901, Greene, IA

Built 1989 Load: 46.6 t ADT: 30

224TH ST

Good

Over: SMALL CREEK

086E13501, Jackson, IA

Built 2017 Load: 46.6 t ADT: 33

US 34 EB

Good

Over: CHURCH CREEK

2.3 mi. E of Jct. SR V63, Jefferson, IA

Built 2007 Load: 46.6 t ADT: 3,900

LOCAL

Good

Over: SMALL STREAM

073042307, Louisa, IA

Built 1984 Load: 46.6 t ADT: 26

LOCAL

Good

Over: FOX RIVER

069162502, Appanoose, IA

Built 1987 Load: 46.7 t ADT: 35

BIG SPRING HATCH

Good

Over: STREAM

IN BIG SPRING FISH HATCHE, Clayton, IA

Built 1992 Load: 46.7 t ADT: 10

J22 150TH ST

Good

Over: WEST NISHNABOTNA RIVER

070413201, Fremont, IA

Built 2015 Load: 46.7 t ADT: 45

RAPID CREEK RD

Good

Over: BR RAPID CR

T80N, R5W, 29, Johnson, IA

Built 2019 Load: 46.7 t ADT: 490

SECRIST RD

Good

Over: BIG CREEK

083050605, Linn, IA

Built 2005 Load: 46.7 t ADT: 1,660

Showing 15,401-15,450 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.