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

FM

Good

Over: NISHNABOTNA RIVER

072382903, Montgomery, IA

Built 1997 Load: 40.1 t ADT: 2,231

LOCAL

Good

Over: STREAM

070223401, Wayne, IA

Built 1994 Load: 40.1 t ADT: 26

FM

Good

Over: W FORK NODAWAY RIVER

074330401, Adair, IA

Built 2009 Load: 40.2 t ADT: 71

FM

Good

Over: WALNUT CREEK

069181904, Appanoose, IA

Built 1995 Load: 40.2 t ADT: 70

30 AVE DR

Good

Over: BRANCH OPOSSUM CREEK

084090400, Benton, IA

Built 2021 Load: 40.2 t ADT: 168

50TH ST

Good

Over: SPRING CREEK

086110303, Benton, IA

Built 2012 Load: 40.2 t ADT: 80

INDIAN CREEK RD

Good

Over: INIDAN CREEK

88-11-17-01-10, Black Hawk, IA

Built 2008 Load: 40.2 t ADT: 137

335TH ST

Good

Over: LITTLE BEAVER CREEK

082273305, Boone, IA

Built 2011 Load: 40.2 t ADT: 40

W AVE

Good

Over: MONTGOMERY CREEK

085253502, Boone, IA

Built 2015 Load: 40.2 t ADT: 30

140TH AVE

Good

Over: CREEK

093362902, Buena Vista, IA

Built 2017 Load: 40.2 t ADT: 40

240TH ST

Good

Over: WILLOW CREEK

083331401, Carroll, IA

Built 2016 Load: 40.2 t ADT: 15

320TH ST

Good

Over: STREAM

079042801, Cedar, IA

Built 2017 Load: 40.2 t ADT: 50

Y14 HOOVER HWY

Good

Over: ROCK CREEK

081013302, Cedar, IA

Built 2016 Load: 40.2 t ADT: 480

CO LINE RD

Good

Over: BR MILL CR

082020201, Cedar, IA

Built 2012 Load: 40.2 t ADT: 15

620TH ST

Good

Over: WILLOW CREEK

090411801, Cherokee, IA

Built 2022 Load: 40.2 t ADT: 15

218TH AVE

Good

Over: SOUTH WEST CREEK

072260103, Clarke, IA

Built 2019 Load: 40.2 t ADT: 71

DOLPHIN AVE

Good

Over: HICKORY CREEK

On Blackberry Rd, Clayton, IA

Built 2013 Load: 40.2 t ADT: 98

130TH ST

Good

Over: ROBERTS CREEK

0.5 miles E Gunder Rd, Clayton, IA

Built 2017 Load: 40.2 t ADT: 62

340TH AVE

Good

Over: CHERRY CR

081E50704, Clinton, IA

Built 2019 Load: 40.2 t ADT: 30

F AVE

Good

Over: BIG CREEK

0.86 E NW Cor 33-85-39, Crawford, IA

Built 2017 Load: 40.2 t ADT: 26

JEWEL CIR

Good

Over: BEAR CREEK

00000, Dallas, IA

Built 2011 Load: 40.2 t ADT: 110

HARVEST AVE

Good

Over: TRIB FABIUS CREEK

067140804, Davis, IA

Built 2018 Load: 40.2 t ADT: 30

197TH ST

Good

Over: SMALL STREAM

197th Ave, 50 N of 295th, Delaware, IA

Built 2015 Load: 40.2 t ADT: 44

255TH AVE

Good

Over: PLUM CREEK

089 04 15 06, Delaware, IA

Built 2013 Load: 40.2 t ADT: 29

PLANK ROAD

Good

Over: HONEY CREEK

070032400, Des Moines, IA

Built 2020 Load: 40.2 t ADT: 373

BUNCOMBE RD

Good

Over: BUNCOMBE CREEK

087E21503, Dubuque, IA

Built 2019 Load: 40.2 t ADT: 30

KARPER HARBOR RD

Good

Over: JOHNS CREEK

087010704, Dubuque, IA

Built 2021 Load: 40.2 t ADT: 90

COTTINGHAM RD

Good

Over: CREEK

088E10104, Dubuque, IA

Built 2017 Load: 40.2 t ADT: 412

CHESTERMAN RD

Good

Over: SOUTH FORK CATFISH CREEK

088E10203, Dubuque, IA

Built 2021 Load: 40.2 t ADT: 70

PILOT GROVE RD

Good

Over: WHITE WATER CREEK

088012403, Dubuque, IA

Built 2013 Load: 40.2 t ADT: 79

E WORTHINGTON

Good

Over: JOHN'S CREEK

088023401, Dubuque, IA

Built 2013 Load: 40.2 t ADT: 481

HALES MILL RD

Good

Over: CREEK

089E20705, Dubuque, IA

Built 2018 Load: 40.2 t ADT: 1,375

DERBY GRANGE RD

Good

Over: CLOIE BRANCH

089E20710, Dubuque, IA

Built 2020 Load: 40.2 t ADT: 638

HICKORY VALLEY RD

Good

Over: HEWITT CREEK

089021406, Dubuque, IA

Built 2022 Load: 40.2 t ADT: 108

PLUM CREEK RD

Good

Over: N FK LITTLE MAQUOKETA

T90NR1W240040, Dubuque, IA

Built 2016 Load: 40.2 t ADT: 26

195TH

Good

Over: CREEK

095160403, Floyd, IA

Built 2020 Load: 40.2 t ADT: 49

E18 130TH ST

Good

Over: WEST BUTTRICKS CREEK

E18 ov W Buttrick Creek, Greene, IA

Built 2018 Load: 40.2 t ADT: 528

P20 REDWOOD RD

Good

Over: NORTH RIVER

078313402, Guthrie, IA

Built 2022 Load: 40.2 t ADT: 309

D55 290TH ST

Good

Over: DRAINAGE

086191101, Hardin, IA

Built 2016 Load: 40.2 t ADT: 69

H46 260TH ST

Good

Over: BERRY BRANCH CREEK

071073001, Henry, IA

Built 2019 Load: 40.2 t ADT: 70

LOCAL

Good

Over: DEVILS RUN CEEK

079112903, Iowa, IA

Built 2006 Load: 40.2 t ADT: 34

140TH AVE

Good

Over: OTTER CREEK

086E22104, Jackson, IA

Built 2014 Load: 40.2 t ADT: 120

S 12TH AVE WEST

Good

Over: SMALL STREAM

000000000, Jasper, IA

Built 2016 Load: 40.2 t ADT: 240

W40 GERMANVILLE RD

Good

Over: BURR CREEK

073080806, Jefferson, IA

Built 2019 Load: 40.2 t ADT: 350

IA 1

Good

Over: UNNAMED STREAM

.4 mi S of jct. SR F12/14, Johnson, IA

Built 2014 Load: 40.2 t ADT: 6,000

IA 136

Good

Over: STREAM

1.1 Mi South of S.R. X-64, Jones, IA

Built 2016 Load: 40.2 t ADT: 750

140TH AVE

Good

Over: BEAR CREEK

084032402, Jones, IA

Built 2019 Load: 40.2 t ADT: 91

COUNTY RD X-44

Good

Over: KITTY CREEK

085030302, Jones, IA

Built 2010 Load: 40.2 t ADT: 1,009

E 1ST ST

Good

Over: KITTY CREEK

000000000, Jones, IA

Built 2017 Load: 40.2 t ADT: 529

200TH AVE

Good

Over: PRAIRIE CREEK

094271701, Kossuth, IA

Built 2019 Load: 40.2 t ADT: 15

Showing 14,251-14,300 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.