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

BREHM LANE

Good

Over: CREEK

089E11007, Dubuque, IA

Built 2018 Load: 32.7 t ADT: 11

FM

Good

Over: LITTLE MAQUOKETA RIVER

089E11607, Dubuque, IA

Built 2005 Load: 32.7 t ADT: 530

LOCAL

Good

Over: LITTLE MAQUOKETA RIVER

089E12005, Dubuque, IA

Built 2004 Load: 32.7 t ADT: 304

FM

Good

Over: CREEK

089E20306, Dubuque, IA

Built 2001 Load: 32.7 t ADT: 913

FM

Good

Over: CREEK

089010806, Dubuque, IA

Built 2002 Load: 32.7 t ADT: 884

LOCAL

Good

Over: CREEK

090E12507, Dubuque, IA

Built 2006 Load: 32.7 t ADT: 60

PFEILER RD

Good

Over: STREAM

9001 24 0050, Dubuque, IA

Built 2016 Load: 32.7 t ADT: 34

FM

Good

Over: CREEK

090013204, Dubuque, IA

Built 2002 Load: 32.7 t ADT: 900

HOCHREIN RD

Good

Over: DRAINAGE

090E12505, Dubuque, IA

Built 2006 Load: 32.7 t ADT: 60

FINLEYS LANDING

Good

Over: BASSWOOD CREEK

000000000, Dubuque, IA

Built 2010 Load: 32.7 t ADT: 329

FINLEYS LANDING

Good

Over: BASSWOOD CREEK

00000, Dubuque, IA

Built 2010 Load: 32.7 t ADT: 329

HERBER RD

Good

Over: DRAINAGE DITCH

R1ET89N35, Dubuque, IA

Built 2015 Load: 32.7 t ADT: 1,908

SLEEPY HOLLOW RD

Good

Over: BLOODY RUN CREEK

090E22805, Dubuque, IA

Built 2016 Load: 32.7 t ADT: 50

MCALLISTER RD

Good

Over: STREAM

08701003, Dubuque, IA

Built 2021 Load: 32.7 t ADT: 78

LOUISE LANE

Good

Over: BORDEAUX RUN

N.W. OF PERU RD, Dubuque, IA

Built 2009 Load: 32.7 t ADT: 684

W 32ND STREET

Good

Over: BEE BRANCH

N.E. OF WILDWOOD DR, Dubuque, IA

Built 2009 Load: 32.7 t ADT: 4,322

210TH ST

Good

Over: JACK CREEK

098320401, Emmet, IA

Built 2011 Load: 32.7 t ADT: 219

LOCAL

Good

Over: SOLDIER CREEK

100331102, Emmet, IA

Built 2004 Load: 32.7 t ADT: 30

LOCAL

Good

Over: DENMARK

098323601, Emmet, IA

Built 1997 Load: 32.7 t ADT: 26

IA 187

Good

Over: MAQUOKETA RIVER

2.1 mi. N of Jct. IA #3, Fayette, IA

Built 2011 Load: 32.7 t ADT: 1,540

50TH ST.

Good

Over: MAQUOKETA

091071301, Fayette, IA

Built 1976 Load: 32.7 t ADT: 59

20TH ST.

Good

Over: GUNDLACH CREEK

091073101, Fayette, IA

Built 1985 Load: 32.7 t ADT: 34

18TH ST.

Good

Over: W BUFFALO CREEK

091083103, Fayette, IA

Built 1977 Load: 32.7 t ADT: 39

W-14

Good

Over: UNNAMED CREEK

091091706, Fayette, IA

Built 1979 Load: 32.7 t ADT: 410

W AVE

Good

Over: UNNAMED CREEK

091102106, Fayette, IA

Built 1969 Load: 32.7 t ADT: 795

95TH ST

Good

Over: SMALL STREAM

092082403, Fayette, IA

Built 2021 Load: 32.7 t ADT: 11

M AVE.

Good

Over: VOLGA RIVER

092083102, Fayette, IA

Built 1977 Load: 32.7 t ADT: 29

WILLOW RD

Good

Over: UNNAMED CREEK

092101704, Fayette, IA

Built 2021 Load: 32.7 t ADT: 11

W AVE

Good

Over: UNNAMED CREEK

092103302, Fayette, IA

Built 1977 Load: 32.7 t ADT: 786

80TH ST

Good

Over: SMALL CREEK

092103601, Fayette, IA

Built 2019 Load: 32.7 t ADT: 49

GRANNIS RD

Good

Over: GRANNIS CR

093083605, Fayette, IA

Built 2001 Load: 32.7 t ADT: 29

X AVE

Good

Over: UNAMED CREEK

093103202, Fayette, IA

Built 2003 Load: 32.7 t ADT: 49

ECHO VALLEY RD.

Good

Over: OTTER CREEK

094082103, Fayette, IA

Built 1971 Load: 32.7 t ADT: 363

APPLE RD

Good

Over: SANDY CREEK

095073503, Fayette, IA

Built 1975 Load: 32.7 t ADT: 410

QUAIL RD

Good

Over: BASS CREEK

095090510, Fayette, IA

Built 1955 Load: 32.7 t ADT: 140

M AVE

Good

Over: SMALL

092081902, Fayette, IA

Built 2018 Load: 32.7 t ADT: 59

290TH ST

Good

Over: SMALL STREAM

095101303, Fayette, IA

Built 2020 Load: 32.7 t ADT: 78

HILL ROAD

Good

Over: UNNAMED CREEK

092081401, Fayette, IA

Built 2021 Load: 32.7 t ADT: 20

A AVE

Good

Over: SANDY CREEK

095072501, Fayette, IA

Built 2021 Load: 32.7 t ADT: 33

6TH AVE SW

Good

Over: OTTER CREEK

091092802, Fayette, IA

Built 1978 Load: 32.7 t ADT: 850

FM

Good

Over: DRY RUN CREEK

094150702, Floyd, IA

Built 2010 Load: 32.7 t ADT: 1,129

LOCAL

Good

Over: CREEK

094160201, Floyd, IA

Built 2008 Load: 32.7 t ADT: 59

LOCAL

Good

Over: PETERS CREEK

094162103, Floyd, IA

Built 1988 Load: 32.7 t ADT: 39

ZINNIA AVE

Good

Over: ACKLEY CREEK

094181902, Floyd, IA

Built 2010 Load: 32.7 t ADT: 20

190TH ST

Good

Over: CREEK

095180303, Floyd, IA

Built 2001 Load: 32.7 t ADT: 26

FM

Good

Over: CREEK

095181102, Floyd, IA

Built 1998 Load: 32.7 t ADT: 717

LOCAL

Good

Over: SMALL

095182401, Floyd, IA

Built 2010 Load: 32.7 t ADT: 49

T18(DANCER AVE)

Good

Over: CREEK

095182702, Floyd, IA

Built 2012 Load: 32.7 t ADT: 206

LOCAL

Good

Over: BEAVER CREEK

096151103, Floyd, IA

Built 1992 Load: 32.7 t ADT: 501

LOCAL

Good

Over: SMALL

096153204, Floyd, IA

Built 2009 Load: 32.7 t ADT: 20

Showing 11,451-11,500 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.