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

X AVE

Good

Over: BRANCH BLACKHAWK CREEK

087150202, Grundy, IA

Built 2018 Load: 32.4 t ADT: 26

230TH ST

Good

Over: BLACK HAWK CREEK

087151201, Grundy, IA

Built 2012 Load: 32.4 t ADT: 33

R AVE

Good

Over: MUNNS CREEK

087161402, Grundy, IA

Built 2016 Load: 32.4 t ADT: 59

180TH ST

Good

Over: BLACK HAWK CREEK

088151801, Grundy, IA

Built 2015 Load: 32.4 t ADT: 44

SR D35

Good

Over: BLACK HAWK CREEK

088153503, Grundy, IA

Built 2011 Load: 32.4 t ADT: 903

G AVE

Good

Over: S FORK OF BEAVER CREEK

089173102, Grundy, IA

Built 2017 Load: 32.4 t ADT: 39

IA 25

Good

Over: MASON CREEK

1.0 mi. S of Jct. IA 44, Guthrie, IA

Built 2011 Load: 32.4 t ADT: 1,750

IA 141

Good

Over: MIDDLE RACCOON RVR & TRL

6.2 MI W OF W JCT IA 25, Guthrie, IA

Built 2014 Load: 32.4 t ADT: 1,910

IA 141

Good

Over: WILLOW CREEK

2.1 MI W OF W JCT IA 25, Guthrie, IA

Built 2014 Load: 32.4 t ADT: 1,910

F63 310TH RD

Good

Over: MIDDLE RIVER

078321701, Guthrie, IA

Built 2021 Load: 32.4 t ADT: 150

LOCUST AVE

Good

Over: MIDDLE RIVER

078322202, Guthrie, IA

Built 2016 Load: 32.4 t ADT: 20

210TH ST

Good

Over: STREAM

080303401, Guthrie, IA

Built 2018 Load: 32.4 t ADT: 11

HICKORY AVE

Good

Over: BRUSHY CREEK

080320502, Guthrie, IA

Built 2017 Load: 32.4 t ADT: 20

P26 VICTORY AVE

Good

Over: STREAM

081300302, Guthrie, IA

Built 2017 Load: 32.4 t ADT: 11

N46 CHESTNUT RD

Good

Over: BRUSHY CREEK

081332102, Guthrie, IA

Built 2014 Load: 32.4 t ADT: 399

IA 650

Good

Over: STREAM

0.4 MI. N. of 160th Rd., Guthrie, IA

Built 2016 Load: 32.4 t

370TH ST

Good

Over: DRAINAGE DITCH

086262401, Hamilton, IA

Built 2017 Load: 32.4 t ADT: 20

D41 280TH ST

Good

Over: CREEK

087250203, Hamilton, IA

Built 2015 Load: 32.4 t ADT: 234

280TH ST

Good

Over: BOONE RIVER

087250601, Hamilton, IA

Built 2019 Load: 32.4 t ADT: 80

B55 160TH ST

Good

Over: DD #8

094250601, Hancock, IA

Built 2017 Load: 32.4 t ADT: 300

110TH ST

Good

Over: E BR BOONE RIVER

094253101, Hancock, IA

Built 2020 Load: 32.4 t ADT: 45

200TH ST

Good

Over: BOONE RIVER

095261501, Hancock, IA

Built 2014 Load: 32.4 t ADT: 26

250TH ST

Good

Over: DD #1&2

096252301, Hancock, IA

Built 2018 Load: 32.4 t ADT: 26

R16 BIRCH AVE

Good

Over: BUFFALO CREEK

097260502, Hancock, IA

Built 2015 Load: 32.4 t ADT: 41

D20 HWY 941

Good

Over: S FORK IOWA RIVER

089222003, Hardin, IA

Built 2014 Load: 32.4 t ADT: 943

S 56

Good

Over: ELK CREEK

088192804, Hardin, IA

Built 2016 Load: 32.4 t ADT: 1,650

H AVE

Good

Over: MINERVA CREEK

086211902, Hardin, IA

Built 2013 Load: 32.4 t ADT: 26

330TH ST

Good

Over: MINERVA CREEK

086213301, Hardin, IA

Built 2014 Load: 32.4 t ADT: 26

F AVE

Good

Over: MINERVA CREEK

086221402, Hardin, IA

Built 2013 Load: 32.4 t ADT: 25

S27

Good

Over: TIPTON CREEK

087220202, Hardin, IA

Built 2021 Load: 32.4 t ADT: 285

IA 183

Good

Over: COBB CREEK

0.5 MI. N SR F20, Harrison, IA

Built 2017 Load: 32.4 t ADT: 730

J20 SALEM RD

Good

Over: MUD CREEK

070052705, Henry, IA

Built 2019 Load: 32.4 t ADT: 400

ASH AVE

Good

Over: ROCK CREEK

70071806, Henry, IA

Built 2016 Load: 32.4 t ADT: 62

OASIS AVE

Good

Over: SOUTH BIG CREEK

071051002, Henry, IA

Built 2014 Load: 32.4 t ADT: 60

W55 FRANKLIN AVE

Good

Over: BNSF RR

071070110, Henry, IA

Built 2019 Load: 32.4 t ADT: 920

SAINT AVE

Good

Over: LITTLE TURKEY RIVER

097110602, Howard, IA

Built 2015 Load: 32.4 t ADT: 11

200TH ST

Good

Over: CRANE CREEK

097121701, Howard, IA

Built 2019 Load: 32.4 t ADT: 79

FM 190TH ST

Good

Over: LITTLE WAPSIPINICON

97141001, Howard, IA

Built 2009 Load: 32.4 t ADT: 638

ELM AVE

Good

Over: DRAINAGE DITCH

097141102, Howard, IA

Built 2013 Load: 32.4 t ADT: 49

135TH ST

Good

Over: S BR TURKEY RIVER

098121103, Howard, IA

Built 2023 Load: 32.4 t ADT: 49

A46 150TH ST

Good

Over: TURKEY RIVER

098122201, Howard, IA

Built 2017 Load: 32.4 t ADT: 717

175TH ST

Good

Over: BR CRANE CREEK

098123103, Howard, IA

Built 2011 Load: 32.4 t ADT: 59

V46 ROBIN AVE

Good

Over: TURKEY RIVER

098123604, Howard, IA

Built 2015 Load: 32.4 t ADT: 108

MAPLE LEAF RD

Good

Over: BR CRANE CREEK

098130404, Howard, IA

Built 2015 Load: 32.4 t ADT: 26

170TH ST

Good

Over: BR MEAD CREEK

098133101, Howard, IA

Built 2012 Load: 32.4 t ADT: 51

130TH ST

Good

Over: BR LITTLE WAPSIPINICON R

098140803, Howard, IA

Built 2012 Load: 32.4 t ADT: 16

140TH ST

Good

Over: LITTLE WAPSIPINICON RVR

098141503, Howard, IA

Built 2015 Load: 32.4 t ADT: 21

170TH ST

Good

Over: WAPSIPINICON RIVER

098143201, Howard, IA

Built 2013 Load: 32.4 t ADT: 20

170TH ST

Good

Over: LITTLE WAPSIPINICON RVR

098143501, Howard, IA

Built 2015 Load: 32.4 t ADT: 82

YANKEE AVE

Good

Over: BR MINOR CREEK

099110102, Howard, IA

Built 2011 Load: 32.4 t ADT: 39

Showing 10,651-10,700 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.