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

S.W.LACKENDER

Good

Over: PICAYUNE CREEK

078072304, Johnson, IA

Built 1994 Load: 43.3 t ADT: 41

LOC 110TH ST

Good

Over: PRAIRIE CREEK

094273101, Kossuth, IA

Built 2010 Load: 43.3 t ADT: 81

FM

Good

Over: ELK CREEK

082432402, Monona, IA

Built 1988 Load: 43.3 t ADT: 45

TAMARACK AVE

Good

Over: WHISKEY CREEK

000000000, Plymouth, IA

Built 2009 Load: 43.3 t ADT: 26

FAWN AVE

Good

Over: BULL RUN

9247290110, Plymouth, IA

Built 2015 Load: 43.3 t ADT: 26

EVERGREEN AVE

Good

Over: BULL RUN

9247300210, Plymouth, IA

Built 2014 Load: 43.3 t ADT: 15

FM

Good

Over: BIG WHISKEY SLOUGH

093432401, Plymouth, IA

Built 2008 Load: 43.3 t ADT: 450

150TH ST

Good

Over: WILLOW CREEK

9344310210, Plymouth, IA

Built 2011 Load: 43.3 t ADT: 15

LOCAL

Good

Over: TURKEY CREEK

069313401, Ringgold, IA

Built 2009 Load: 43.3 t ADT: 29

US 30 WB

Good

Over: DEER CREEK

0.6 MILE W OF JCT US 63, Tama, IA

Built 2010 Load: 43.3 t ADT: 3,700

US 30 EB

Good

Over: DEER CREEK

0.6 mi. W of jct. US 63, Tama, IA

Built 2010 Load: 43.3 t ADT: 3,700

LOCAL

Good

Over: DEER CREEK

090292301, Webster, IA

Built 2009 Load: 43.3 t ADT: 159

LOCAL

Good

Over: STREAM

088472401, Woodbury, IA

Built 2008 Load: 43.3 t ADT: 120

330TH ST

Good

Over: THREE MILE CREEK

1.5 mi E of P33 on 330th, Adair, IA

Built 2015 Load: 43.4 t ADT: 26

A26 IOWA RIVER DR

Good

Over: BR UPPER IOWA RIVER

T100N R4W SEC 20, Allamakee, IA

Built 2018 Load: 43.4 t ADT: 660

LINCOLN-MAIN ST

Good

Over: CEDAR RIVER

000000000, Black Hawk, IA

Built 1997 Load: 43.4 t ADT: 2,380

MISSISSIPPI RD

Good

Over: SMALL

093022908, Clayton, IA

Built 1979 Load: 43.4 t ADT: 157

245TH ST

Good

Over: AMES CREEK

081E41603, Clinton, IA

Built 1988 Load: 43.4 t ADT: 1,930

212TH ST

Good

Over: WEST SILVER CREEK

082E33503, Clinton, IA

Built 2003 Load: 43.4 t ADT: 310

KEMP RD

Good

Over: CREEK

088E30706, Dubuque, IA

Built 2017 Load: 43.4 t ADT: 511

VASKE RD

Good

Over: N FORK MAQUOKETA RIVER

089020703, Dubuque, IA

Built 2018 Load: 43.4 t ADT: 49

US 61 SB

Good

Over: BNSF RR

3.9 MI. N OF JCT. US 218, Lee, IA

Built 1999 Load: 43.4 t ADT: 3,500

SUMAC AVE

Good

Over: STREAM

084422206, Monona, IA

Built 2019 Load: 43.4 t ADT: 40

TANAGER AVE

Good

Over: WATERMAN CREEK

097401101, O'Brien, IA

Built 2022 Load: 43.4 t ADT: 35

LOCAL

Good

Over: EPPING CREEK

097403602, O'Brien, IA

Built 1985 Load: 43.4 t ADT: 72

FM

Good

Over: OTTER CREEK

099421401, Osceola, IA

Built 1990 Load: 43.4 t ADT: 679

I 29 NB

Good

Over: MOSQUITO CK,RR,BIKE PATH

0.4 MI. S OF JCT. US 275, Pottawattamie, IA

Built 2016 Load: 43.4 t ADT: 12,100

SKI HILL LOOP

Good

Over: PIGEON CREEK

076441203, Pottawattamie, IA

Built 1991 Load: 43.4 t ADT: 120

LOCAL

Good

Over: RACCOON RIVER

089361301, Sac, IA

Built 1985 Load: 43.4 t ADT: 30

A54B

Good

Over: NO NAME CREEK

097481301, Sioux, IA

Built 2021 Load: 43.4 t ADT: 609

190TH ST

Good

Over: DD 70

.25 Mi S of NW Cor., Story, IA

Built 2017 Load: 43.4 t ADT: 578

FM

Good

Over: FOX RIVER

068112502, Van Buren, IA

Built 2003 Load: 43.4 t ADT: 500

FM

Good

Over: DES MOINES RIVER

086270105, Webster, IA

Built 2002 Load: 43.4 t ADT: 199

A39 390TH

Good

Over: STREAM

East of Wheelerwood Ave., Worth, IA

Built 2021 Load: 43.4 t ADT: 118

G61 310TH ST

Good

Over: STREAM

1.7 mi W of N51 on G61, Adair, IA

Built 2017 Load: 43.7 t ADT: 45

H 33 180TH STREET

Good

Over: MOUNT ZION BRANCH

072331301, Adams, IA

Built 2021 Load: 43.7 t ADT: 409

YELLOW RVR RD

Good

Over: NORFOLK CREEK

T96NR5WSEC6NE, Allamakee, IA

Built 2015 Load: 43.7 t ADT: 98

D38 POYNER RD

Good

Over: INDIAN CREEK

88-12-25-01-10, Black Hawk, IA

Built 2023 Load: 43.7 t ADT: 776

SB IA 27 RAMP

Good

Over: DRY RUN CRK & CEDAR RVR

1.2 MI. S OF JCT. US 218, Black Hawk, IA

Built 1992 Load: 43.7 t ADT: 2,940

C43 555TH ST

Good

Over: BRANCH RACCOON RIVER

091361003, Buena Vista, IA

Built 2016 Load: 43.7 t ADT: 100

VICTORIA RD

Good

Over: SEVEN MILE CREEK

074362001, Cass, IA

Built 2012 Load: 43.7 t ADT: 35

N16 OLIVE ST

Good

Over: BRANCH OF BUCK CREEK

077360902, Cass, IA

Built 2021 Load: 43.7 t ADT: 1,524

OLD MUSCATINE RD

Good

Over: OTTER CREEK

079022503, Cedar, IA

Built 2023 Load: 43.7 t ADT: 70

C 5X HARVESTER RD

Good

Over: BEAR CREEK

00000, Clayton, IA

Built 2011 Load: 43.7 t ADT: 108

130TH AVE

Good

Over: WEST ROCK CREEK

081E13406, Clinton, IA

Built 2005 Load: 43.7 t ADT: 1,060

225TH STREET

Good

Over: SILVER CREEK

081E30208, Clinton, IA

Built 1997 Load: 43.7 t ADT: 200

220TH STREET

Good

Over: CHERRY CREEK

081E40101, Clinton, IA

Built 1989 Load: 43.7 t ADT: 1,010

275TH AVE

Good

Over: SUGAR CREEK

083E30104, Clinton, IA

Built 2016 Load: 43.7 t ADT: 26

250TH AVENUE

Good

Over: CREEK

083E32202, Clinton, IA

Built 1958 Load: 43.7 t ADT: 950

115TH ST.

Good

Over: ELK RIVER

083E61009, Clinton, IA

Built 1992 Load: 43.7 t ADT: 120

Showing 14,901-14,950 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.