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

IA 10

Good

Over: WILLOW CREEK

0.8 mi. E of SR L14, Sioux, IA

Built 2008 Load: 32.5 t ADT: 1,980

FM

Good

Over: TURKEY RIVER

097101101, Winneshiek, IA

Built 1979 Load: 32.5 t ADT: 128

DOUGLAS PKWY

Good

Over: WALNUT CREEK

O37550370, Dallas, IA

Built 2006 Load: 32.6 t ADT: 1,807

210TH ST

Good

Over: SMALL CREEK

080333401, Guthrie, IA

Built 2017 Load: 32.6 t ADT: 15

IA 92

Good

Over: ENGLISH RIVER

1.4 mi. E of E jct. IA 5, Marion, IA

Built 1978 Load: 32.6 t ADT: 3,870

FM

Good

Over: FLOYD RIVER

097422102, O'Brien, IA

Built 1962 Load: 32.6 t ADT: 240

BUCHANAN AVE

Good

Over: STREAM

087381902, Sac, IA

Built 2000 Load: 32.6 t ADT: 20

IRR BIA RTE 1101

Good

Over: DRAINAGE DITCH

CASINO ENTR AT JCT HWY 30, Tama, IA

Built 1994 Load: 32.6 t ADT: 5,358

IRR BIA RTE 2

Good

Over: IOWA RIVER OVERFLOW

6KM TO IOWA P.O., Tama, IA

Built 1998 Load: 32.6 t ADT: 250

US 63 NB

Good

Over: COMSTOCK CREEK

0.6 MI. S OF SR T67, Wapello, IA

Built 1997 Load: 32.6 t ADT: 4,600

P33 HENRY WALLACE

Good

Over: CREEK

074303102, Adair, IA

Built 2001 Load: 32.7 t ADT: 1,673

FM

Good

Over: W FK MIDDLE NODAWAY RVR

075331004, Adair, IA

Built 1982 Load: 32.7 t ADT: 60

FM-125TH STREET

Good

Over: STREAM

073341303, Adams, IA

Built 2004 Load: 32.7 t ADT: 170

FM

Good

Over: BRANCH YELLOW RIVER

096042405, Allamakee, IA

Built 2001 Load: 32.7 t ADT: 128

LOCAL

Good

Over: BRANCH YELLOW RIVER

096051506, Allamakee, IA

Built 2001 Load: 32.7 t ADT: 29

LOCAL RD

Good

Over: TEEPLE CREEK

097061103, Allamakee, IA

Built 1988 Load: 32.7 t ADT: 29

DOEHLER DR

Good

Over: BR VILLAGE CREEK

098031811, Allamakee, IA

Built 2000 Load: 32.7 t ADT: 20

FM

Good

Over: UPPER IOWA RIVER

099062906, Allamakee, IA

Built 1994 Load: 32.7 t ADT: 49

A26 IOWA RIVER DR

Good

Over: BRANCH IOWA RIVER

100042104, Allamakee, IA

Built 2022 Load: 32.7 t ADT: 648

LOCAL

Good

Over: SMALL STREAM

098030714, Allamakee, IA

Built 2000 Load: 32.7 t ADT: 29

269TH AVE

Good

Over: SMALL CREEK

067160704, Appanoose, IA

Built 2018 Load: 32.7 t ADT: 20

J59 610TH ST

Good

Over: SPRING CREEK

067161805, Appanoose, IA

Built 2020 Load: 32.7 t ADT: 40

236TH AVE

Good

Over: PACKARD CREEK

067171003, Appanoose, IA

Built 2018 Load: 32.7 t ADT: 41

LOCAL

Good

Over: SMALL STREAM

0671821606, Appanoose, IA

Built 2010 Load: 32.7 t ADT: 45

614TH ST

Good

Over: UNNAMED STREAM

067192000, Appanoose, IA

Built 2022 Load: 32.7 t ADT: 21

LOCAL

Good

Over: SMALL STREAM

068162506, Appanoose, IA

Built 1986 Load: 32.7 t ADT: 26

DEWEY RD

Good

Over: STREAM

068170903, Appanoose, IA

Built 2018 Load: 32.7 t ADT: 73

LOCAL

Good

Over: STREAM

068183604, Appanoose, IA

Built 1995 Load: 32.7 t ADT: 113

110TH AVE

Good

Over: COOPER CREEK

068191702, Appanoose, IA

Built 2020 Load: 32.7 t ADT: 30

565TH ST

Good

Over: STREAM

068192605, Appanoose, IA

Built 2012 Load: 32.7 t ADT: 21

LOCAL

Good

Over: COOPER CREEK

069173030, Appanoose, IA

Built 2006 Load: 32.7 t ADT: 413

FM

Good

Over: WALNUT CREEK

069192301, Appanoose, IA

Built 2002 Load: 32.7 t ADT: 45

302ND AVE

Good

Over: STREAM

070162104, Appanoose, IA

Built 2019 Load: 32.7 t ADT: 47

LOCAL

Good

Over: SOAP CREEK

070171002, Appanoose, IA

Built 2004 Load: 32.7 t ADT: 91

413TH ST

Good

Over: BUCK BRANCH

070181106, Appanoose, IA

Built 1994 Load: 32.7 t ADT: 73

467TH ST

Good

Over: SNORT CREEK

069170303, Appanoose, IA

Built 2008 Load: 32.7 t ADT: 41

FM

Good

Over: CREEK

080342301, Audubon, IA

Built 2003 Load: 32.7 t ADT: 428

FM

Good

Over: CREEK

080342301, Audubon, IA

Built 2003 Load: 32.7 t ADT: 428

IA 21

Good

Over: BRANCH SALT CREEK

0.3 mi. S of Jct. SR E44, Benton, IA

Built 1983 Load: 32.7 t ADT: 1,470

LOCAL

Good

Over: KNAPP CREEK

082092502, Benton, IA

Built 1989 Load: 32.7 t ADT: 59

75 ST DR

Good

Over: SMALL STREAM

082111003, Benton, IA

Built 2000 Load: 32.7 t ADT: 71

LOCAL

Good

Over: BR BUCKEYE CREEK

082122207, Benton, IA

Built 1995 Load: 32.7 t ADT: 45

LOCAL

Good

Over: DRY CK

083092002, Benton, IA

Built 1991 Load: 32.7 t ADT: 39

LOCAL

Good

Over: DRY CREEK

083092102, Benton, IA

Built 1985 Load: 32.7 t ADT: 70

LOCAL

Good

Over: WILDCAT CREEK

083100602, Benton, IA

Built 1995 Load: 32.7 t ADT: 5

LOCAL

Good

Over: MILLER CREEK

086121801, Benton, IA

Built 1993 Load: 32.7 t ADT: 60

V 37

Good

Over: SMALL CREEK

086121802, Benton, IA

Built 2013 Load: 32.7 t ADT: 1,370

V 37

Good

Over: WOLF CREEK

086121802, Benton, IA

Built 2013 Load: 32.7 t ADT: 1,345

FM

Good

Over: WOLF CREEK

086121903, Benton, IA

Built 1988 Load: 32.7 t ADT: 200

LOCAL

Good

Over: BR BUFFALO CREEK

082100402, Benton, IA

Built 1988 Load: 32.7 t ADT: 60

Showing 11,101-11,150 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.