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

LOCAL

Good

Over: BRUSHY CREEK

080311902, Guthrie, IA

Built 2011 Load: 42.4 t ADT: 29

42ND ST

Good

Over: SYBILL CREEK

083021803, Jones, IA

Built 2014 Load: 42.4 t ADT: 69

BLUEBIRD RD

Good

Over: FARM CREEK

086013403, Jones, IA

Built 2018 Load: 42.4 t ADT: 39

212 AVE

Good

Over: SUGAR CREEK

066062505, Lee, IA

Built 2011 Load: 42.4 t ADT: 50

LOST CREEK RD

Good

Over: LOST CREEK

068030710, Lee, IA

Built 2016 Load: 42.4 t ADT: 40

OAK DRIVE

Good

Over: INDIAN CREEK

083063010, Linn, IA

Built 2023 Load: 42.4 t

E16 SAWYER RD

Good

Over: HEATON CREEK

T85N, R06W, 2, Linn, IA

Built 2018 Load: 42.4 t ADT: 1,768

US 61

Good

Over: HONEY CREEK

0.1 mi. N of jct. SR H16, Louisa, IA

Built 1997 Load: 42.4 t ADT: 4,420

NB US 63

Good

Over: MUCHAKINOK CREEK

0.3 MILES SOUTH OF SR G71, Mahaska, IA

Built 1997 Load: 42.4 t ADT: 6,250

250TH ST

Good

Over: WALNUT CREEK

071391903, Montgomery, IA

Built 2011 Load: 42.4 t ADT: 30

H20 140TH ST

Good

Over: SEVEN MILE CREEK

073362901, Montgomery, IA

Built 2022 Load: 42.4 t ADT: 29

US 61 NB

Good

Over: PINE CREEK

6.3 mi. N of Jct. IA 38, Muscatine, IA

Built 1990 Load: 42.4 t ADT: 5,200

L66 340TH ST

Good

Over: IAIS RR

076412302, Pottawattamie, IA

Built 2015 Load: 42.4 t ADT: 270

FIR RD

Good

Over: MOSQUITO CREEK

080401202, Shelby, IA

Built 2016 Load: 42.4 t ADT: 50

170TH ST

Good

Over: EAST BR INDIAN CREEK

084221101, Story, IA

Built 1977 Load: 42.4 t ADT: 30

SR J55

Good

Over: HONEY CREEK

067330503, Taylor, IA

Built 2011 Load: 42.4 t ADT: 71

220TH ST

Good

Over: WEST 102 RIVER

068350403, Taylor, IA

Built 2016 Load: 42.4 t ADT: 29

J12 110TH RD

Good

Over: LICK CREEK

070100903, Van Buren, IA

Built 2020 Load: 42.4 t ADT: 70

G64 STONE ST

Good

Over: SOUTH RIVER BRANCH

074251401, Warren, IA

Built 2023 Load: 42.4 t ADT: 50

FM(TO STATE)

Good

Over: LIZARD CREEK

090301901, Webster, IA

Built 2010 Load: 42.4 t ADT: 21

K67 HANCOCK AVE

Good

Over: WOLF CREEK

088453602, Woodbury, IA

Built 2020 Load: 42.4 t ADT: 30

LOCAL

Good

Over: BEAVER CREEK

082281505, Boone, IA

Built 1997 Load: 42.5 t ADT: 34

FM

Good

Over: IOWAY CREEK

084251201, Boone, IA

Built 2002 Load: 42.5 t ADT: 170

330TH

Good

Over: SHELL ROCK RIVER

097190803, Cerro Gordo, IA

Built 2003 Load: 42.5 t ADT: 196

BIRCH AVE

Good

Over: EAST SOLDIER RIVER

084412304, Crawford, IA

Built 1999 Load: 42.5 t ADT: 104

40TH ST

Good

Over: LITTLE WAPSI RIVER

091102103, Fayette, IA

Built 1997 Load: 42.5 t ADT: 108

FM 190TH ST

Good

Over: OTTER CREEK

092200901, Franklin, IA

Built 1997 Load: 42.5 t ADT: 619

LOCAL

Good

Over: BLACKHAWK CREEK

087160902, Grundy, IA

Built 2002 Load: 42.5 t ADT: 29

R AVE

Good

Over: BRANCH BLACK HAWK CREEK

087161402, Grundy, IA

Built 2000 Load: 42.5 t ADT: 59

FM

Good

Over: BIG CREEK

071061708, Henry, IA

Built 1999 Load: 42.5 t ADT: 940

FM

Good

Over: HONEY CREEK

085191603, Marshall, IA

Built 2004 Load: 42.5 t ADT: 354

FM

Good

Over: FLOYD RIVER

097421102, O'Brien, IA

Built 2004 Load: 42.5 t ADT: 199

FM

Good

Over: GRAND RIVER

073291109, Union, IA

Built 2007 Load: 42.5 t ADT: 270

FM

Good

Over: WEST CREEK

074240905, Warren, IA

Built 2002 Load: 42.5 t ADT: 60

FM

Good

Over: WEST CREEK

075241503, Warren, IA

Built 1996 Load: 42.5 t ADT: 278

OUTER RD.

Good

Over: OVER ABANDON RR

091092712, Fayette, IA

Built 1973 Load: 42.6 t ADT: 1,561

LOCAL

Good

Over: BATTLE CREEK

088401802, Ida, IA

Built 2001 Load: 42.6 t ADT: 11

FM

Good

Over: WOLF CREEK

081211001, Jasper, IA

Built 2000 Load: 42.6 t ADT: 60

SB US 63

Good

Over: MUCHAKINOK CREEK

0.3 mi. S of Jct. SR G71, Mahaska, IA

Built 1997 Load: 42.6 t ADT: 6,250

IA 137

Good

Over: OVER UP RR

0.2 MI S of Jct. SR T-61, Monroe, IA

Built 1993 Load: 42.6 t ADT: 3,910

NB US 169

Good

Over: CC RR

0.5 mi S of IA 7, Webster, IA

Built 2010 Load: 42.6 t ADT: 4,400

FM

Good

Over: DES MOINES RIVER

088281714, Webster, IA

Built 1995 Load: 42.6 t ADT: 1,746

130TH ST

Good

Over: TRIB TO SOAP CREEK

070151403, Davis, IA

Built 2021 Load: 42.7 t ADT: 45

US 34 EB

Good

Over: BNSF RR

3.4 mi. E of Jct. SR V63, Jefferson, IA

Built 2008 Load: 42.7 t ADT: 7,800

WHITE PINE ROAD

Good

Over: BRANCH PAINT CREEK

097042305, Allamakee, IA

Built 2020 Load: 42.8 t ADT: 128

180TH ST

Good

Over: BEAVER CREEK

084281601, Boone, IA

Built 2020 Load: 42.8 t ADT: 71

FM 290TH ST

Good

Over: LIME CREEK

087101201, Buchanan, IA

Built 2004 Load: 42.8 t ADT: 344

LOCAL

Good

Over: BEAVER CREEK

090172202, Butler, IA

Built 2009 Load: 42.8 t ADT: 73

STONE MILL RD

Good

Over: ROCK CREEK

080031307, Cedar, IA

Built 2011 Load: 42.8 t ADT: 190

ASH ST

Good

Over: W BR BEAVER DAM CREEK

0.1 MI E S25, Cerro Gordo, IA

Built 2018 Load: 42.8 t ADT: 599

Showing 14,801-14,850 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.