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 4

Good

Over: DRAINAGE DITCH #2

1.6 MI. N OF CO. RD. B14, Emmet, IA

Built 2019 Load: 32.4 t ADT: 1,740

200TH ST

Good

Over: W FORK DES MOINES RIVER

099333101, Emmet, IA

Built 2012 Load: 32.4 t ADT: 419

B60 APPLE RD (SDB)

Good

Over: ROAD CREEK

095073503, Fayette, IA

Built 2014 Load: 32.4 t ADT: 10

ZINNIA AVE

Good

Over: DRY RUN

094180606, Floyd, IA

Built 2014 Load: 32.4 t ADT: 44

ECHO AVE

Good

Over: BEEMIS CREEK

094181102, Floyd, IA

Built 2011 Load: 32.4 t ADT: 29

280TH ST

Good

Over: ACKLEY CREEK

094182001, Floyd, IA

Built 2016 Load: 32.4 t ADT: 20

NOBLE AVE

Good

Over: CREEK

095160502, Floyd, IA

Built 2014 Load: 32.4 t ADT: 49

T34 JERSEY AVE

Good

Over: SMALL CREEK

095170302, Floyd, IA

Built 2022 Load: 32.4 t ADT: 49

B47 215TH ST

Good

Over: CREEK

095181805, Floyd, IA

Built 2020 Load: 32.4 t ADT: 560

VICTORY

Good

Over: LITTLE CEDAR TRIBUTARY

096151002, Floyd, IA

Built 2018 Load: 32.4 t ADT: 33

130TH ST

Good

Over: STREAM

096160601, Floyd, IA

Built 2023 Load: 32.4 t ADT: 29

170TH ST

Good

Over: STREAM

096172601, Floyd, IA

Built 2021 Load: 32.4 t ADT: 20

FM

Good

Over: SKUNK CREEK

097172506, Floyd, IA

Built 2010 Load: 32.4 t ADT: 29

110TH ST

Good

Over: SKUNK CREEK

097172601, Floyd, IA

Built 2013 Load: 32.4 t ADT: 78

VICTORY AVE

Good

Over: LITTLE CEDAR TRIBUTARY

096150302, Floyd, IA

Built 2013 Load: 32.4 t ADT: 20

ROTARY PARK RD

Good

Over: CREEK

096162604, Floyd, IA

Built 2016 Load: 32.4 t ADT: 148

200TH

Good

Over: DRY RUN

095181103, Floyd, IA

Built 2018 Load: 32.4 t ADT: 26

170TH ST

Good

Over: LITTLE CEDAR

096152303, Floyd, IA

Built 2019 Load: 32.4 t ADT: 50

150TH

Good

Over: CREEK

096161701, Floyd, IA

Built 2020 Load: 32.4 t ADT: 78

US 65

Good

Over: SPRING CREEK

1.3 MI. N OF IA 3, Franklin, IA

Built 2020 Load: 32.4 t ADT: 3,960

THRUSH AVE

Good

Over: SMALL STREAM

90192904, Franklin, IA

Built 2013 Load: 32.4 t ADT: 30

NUTHATCH AVE

Good

Over: DRAINAGE DITCH NO 13

090202004, Franklin, IA

Built 2019 Load: 32.4 t ADT: 26

40TH ST

Good

Over: DRAINAGE DITCH NO 13

90202903, Franklin, IA

Built 2014 Load: 32.4 t ADT: 20

30TH ST

Good

Over: DRAINAGE DITCH NO 13

90203301, Franklin, IA

Built 2021 Load: 32.4 t ADT: 29

30TH ST

Good

Over: DRAINAGE DITCH NO 5

90213501, Franklin, IA

Built 2014 Load: 32.4 t ADT: 20

C51 115TH ST

Good

Over: SMALL STREAM

91191505, Franklin, IA

Built 2016 Load: 32.4 t ADT: 59

S41 MALLARD AVE

Good

Over: DD NO 6

91213102, Franklin, IA

Built 2021 Load: 32.4 t ADT: 1,277

FM 190TH ST

Good

Over: WEST FORK OF CEDAR CREEK

092191201, Franklin, IA

Built 2011 Load: 32.4 t ADT: 59

WARBLER AVE

Good

Over: SMALL STREAM

92192302, Franklin, IA

Built 2016 Load: 32.4 t ADT: 20

C33 YARROW AVE

Good

Over: SMALL STREAM

092192402, Franklin, IA

Built 2014 Load: 32.4 t ADT: 34

200TH STREET

Good

Over: BUFFALO CREEK

92210101, Franklin, IA

Built 2021 Load: 32.4 t ADT: 26

INDIGO AVE

Good

Over: BUFFALO CREEK

92210402, Franklin, IA

Built 2015 Load: 32.4 t ADT: 51

INDIGO AVE

Good

Over: SPRING CREEK

92212102, Franklin, IA

Built 2023 Load: 32.4 t ADT: 59

LARK AVE

Good

Over: SPRING CREEK

92212502, Franklin, IA

Built 2015 Load: 32.4 t ADT: 91

VIOLET AVE

Good

Over: SMALL STREAM

93192204, Franklin, IA

Built 2014 Load: 32.4 t ADT: 11

S53 (RAVEN AVE)

Good

Over: SMALL STREAM

093202504, Franklin, IA

Built 2014 Load: 32.4 t ADT: 59

95TH ST

Good

Over: UNNAMED STREAM

91202503, Franklin, IA

Built 2017 Load: 32.4 t ADT: 26

C13 250TH ST

Good

Over: SMALL CREEK

093200801102500, Franklin, IA

Built 2017 Load: 32.4 t ADT: 903

C13 GRANT ST

Good

Over: BAILEY CREEK

093200803, Franklin, IA

Built 2017 Load: 32.4 t ADT: 919

FRANKLIN ST

Good

Over: BEAVER CREEK

90193504105073, Franklin, IA

Built 2020 Load: 32.4 t ADT: 1,409

J40 MANTI ROAD

Good

Over: FISHER CREEK

069403503, Fremont, IA

Built 2021 Load: 32.4 t ADT: 142

IA 2 EB

Good

Over: MISSOURI RIVER OVERFLOW

0.5 MI. E. of Missouri R., Fremont, IA

Built 2019 Load: 32.4 t ADT: 4,150

IA 2 WB

Good

Over: MISSOURI RIVER OVERFLOW

0.5 MI. E. of Missouri R., Fremont, IA

Built 2020 Load: 32.4 t ADT: 4,150

IA 2 EB

Good

Over: MISSOURI RIVER OVERFLOW

2.2 MI. W. OF I-29, Fremont, IA

Built 2021 Load: 32.4 t ADT: 4,150

IA 2 WB

Good

Over: MISSOURI RIVER OVERFLOW

2.2 MI. W OF I-29, Fremont, IA

Built 2021 Load: 32.4 t ADT: 4,150

IA 2 EB

Good

Over: MISSOURI RIVER OVERFLOW

1.6 MI. W. OF I-29, Fremont, IA

Built 2021 Load: 32.4 t ADT: 4,150

IA 2 WB

Good

Over: MISSOURI RIVER OVERFLOW

1.6 MI. W. OF I-29, Fremont, IA

Built 2021 Load: 32.4 t ADT: 4,150

H AVE

Good

Over: BRANCH WOLF CREEK

086173004, Grundy, IA

Built 2018 Load: 32.4 t ADT: 29

T37 M AVE

Good

Over: WOLF CREEK

086173602, Grundy, IA

Built 2019 Load: 32.4 t ADT: 79

300TH ST

Good

Over: WOLF CREEK

086181501, Grundy, IA

Built 2020 Load: 32.4 t ADT: 26

Showing 10,601-10,650 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.