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

GREENHILL ROAD

Good

Over: W BR DRY RUN CREEK

0.4 MI N OF UNIV. AVE, Black Hawk, IA

Built 2018 Load: 44.4 t ADT: 143

FM

Good

Over: RACOON RIVER

090361201, Buena Vista, IA

Built 2010 Load: 44.4 t ADT: 40

IA 188

Good

Over: SHELL ROCK RIVER

1.5 MI. N OF JCT. IA 3, Butler, IA

Built 1992 Load: 44.4 t ADT: 2,010

T16 (DODGE AVE)

Good

Over: BEAVER CREEK

090182204, Butler, IA

Built 2014 Load: 44.4 t ADT: 501

GRAND PRAIRIE PKWY

Good

Over: SUGAR CREEK

GPPW over Sugar Creek, Dallas, IA

Built 2016 Load: 44.4 t ADT: 5,474

BOONEVILLE RD

Good

Over: JOHNSON CREEK

Booneville Rd over JCreek, Dallas, IA

Built 2022 Load: 44.4 t ADT: 66

LOCAL

Good

Over: LITTLE SIOUX RIVER

098370401, Dickinson, IA

Built 2010 Load: 44.4 t ADT: 72

150 TH

Good

Over: EAST BUTTRICKS CREEK

085293103, Greene, IA

Built 1987 Load: 44.4 t ADT: 41

US 20 EB

Good

Over: UPRR

1.5 MILES E OF JCT SR S27, Hardin, IA

Built 1999 Load: 44.4 t ADT: 4,650

LOCAL

Good

Over: MILL RACE

081092612, Iowa, IA

Built 2001 Load: 44.4 t ADT: 1,002

IA 1

Good

Over: STREAM

0.6 mi. N of SR F52, Johnson, IA

Built 2020 Load: 44.4 t ADT: 6,300

W38 BLACK HAWK AVE

Good

Over: OLD MANS CREEK

078080504, Johnson, IA

Built 2020 Load: 44.4 t ADT: 80

TOUR ROAD

Good

Over: DRAINAGE DITCH

SEC 35 T98N R28W, Kossuth, IA

Built 1994 Load: 44.4 t ADT: 5

E16

Good

Over: RUSH CREEK

085422401, Monona, IA

Built 2021 Load: 44.4 t ADT: 627

VAN BUREN AVE

Good

Over: WATERMAN CREEK

97390702, O'Brien, IA

Built 2020 Load: 44.4 t ADT: 15

NOBLE AVE

Good

Over: MUD CREEK

090440602, Plymouth, IA

Built 2004 Load: 44.4 t ADT: 50

160TH ST

Good

Over: DEEP CREEK

92440301, Plymouth, IA

Built 2015 Load: 44.4 t ADT: 40

130TH ST

Good

Over: BROKEN KETTLE CREEK

934723011040, Plymouth, IA

Built 2013 Load: 44.4 t ADT: 26

FM

Good

Over: DES MOINES RIVER

NW 66th over Des Moines, Polk, IA

Built 2016 Load: 44.4 t ADT: 11,354

NE 150TH AVE

Good

Over: SKUNK RIVER

081231401, Polk, IA

Built 2012 Load: 44.4 t ADT: 142

IA 92

Good

Over: MIDDLE SILVER CREEK

0.2 MI. E of W JCT SR L55, Pottawattamie, IA

Built 2009 Load: 44.4 t ADT: 4,940

LOCAL

Good

Over: STREAM

072301206, Union, IA

Built 2007 Load: 44.4 t ADT: 11

FM

Good

Over: CREEK

073293401, Union, IA

Built 2004 Load: 44.4 t ADT: 50

IA 22

Good

Over: ENGLISH RIVER

2.3 mi. W of IA 1, Washington, IA

Built 1994 Load: 44.4 t ADT: 3,330

FM

Good

Over: SMALL STREAM

085363302, Carroll, IA

Built 1984 Load: 44.5 t ADT: 588

260TH ST

Good

Over: BEEMIS CREEK

094181001, Floyd, IA

Built 2013 Load: 44.5 t ADT: 26

EB US 30

Good

Over: PLEASANT RUN

1.8 mi. W of Jct US 151, Linn, IA

Built 2002 Load: 44.5 t ADT: 11,750

260TH ST

Good

Over: MUD CREEK

091442901, Plymouth, IA

Built 1996 Load: 44.5 t ADT: 50

270TH ST

Good

Over: MUD CREEK

091443101, Plymouth, IA

Built 1995 Load: 44.5 t ADT: 60

270TH ST

Good

Over: DRY BRANCH

091443301, Plymouth, IA

Built 1997 Load: 44.5 t ADT: 45

220TH ST

Good

Over: PERRY CREEK

091470101, Plymouth, IA

Built 1997 Load: 44.5 t ADT: 26

LOCAL

Good

Over: SHANGHAR CREEK

074322702, Adair, IA

Built 2009 Load: 44.6 t ADT: 30

LOCAL

Good

Over: SHANGHAR CREEK

074323402, Adair, IA

Built 2009 Load: 44.6 t ADT: 5

269TH AVE

Good

Over: SMALL CREEK

R3ET84N SEC 26 SW, Jackson, IA

Built 2017 Load: 44.6 t ADT: 20

IA 330 SB

Good

Over: CLEAR CREEK

1.7 MI S OF S JCT SR S52, Marshall, IA

Built 2002 Load: 44.6 t ADT: 4,150

US 6

Good

Over: BEAR CREEK

1.5 mi W of W jct. SR V18, Poweshiek, IA

Built 2008 Load: 44.6 t ADT: 2,040

90TH AVE

Good

Over: CREEK

080E22106, Scott, IA

Built 2002 Load: 44.6 t ADT: 90

IA 92

Good

Over: NORTH FORK LONG CREEK

0.7 mi. W of Jct. US 218, Washington, IA

Built 2001 Load: 44.6 t ADT: 3,620

110TH AVE

Good

Over: COOPER CREEK

068190802, Appanoose, IA

Built 2021 Load: 44.7 t ADT: 30

150TH AVE

Good

Over: WOLF BRANCH CREEK

069191202, Appanoose, IA

Built 2021 Load: 44.7 t ADT: 35

FM

Good

Over: PRAIRIE CREEK

082102608, Benton, IA

Built 2002 Load: 44.7 t ADT: 206

E22 61ST ST

Good

Over: STEIN CREEK

085123101, Benton, IA

Built 2015 Load: 44.7 t ADT: 340

120TH ST

Good

Over: HUNTER CREEK

090091803, Buchanan, IA

Built 2000 Load: 44.7 t ADT: 1,100

G16 BOSTON RD

Good

Over: BRANCH OF BUCK CREEK

077360901, Cass, IA

Built 2022 Load: 44.7 t ADT: 89

LOCAL 120 AVE

Good

Over: BUFFALO CREEK

087062804, Delaware, IA

Built 2003 Load: 44.7 t ADT: 44

20TH ST

Good

Over: LITTLE WAPSI RIVER

091103203, Fayette, IA

Built 2006 Load: 44.7 t ADT: 59

78TH ST

Good

Over: LITTLE WAPSI RIVER

092103203, Fayette, IA

Built 2006 Load: 44.7 t ADT: 15

W55 ACORN RD

Good

Over: BEAVER CREEK

094072404, Fayette, IA

Built 2022 Load: 44.7 t ADT: 177

SPRUCE AVE

Good

Over: BAILEYE CREEK

093191804, Franklin, IA

Built 1997 Load: 44.7 t ADT: 5

LOCAL ROAD

Good

Over: BRANCH BLACK HAWK CREEK

088151102, Grundy, IA

Built 2006 Load: 44.7 t ADT: 49

Showing 15,001-15,050 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.