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

E 18 (130TH ST)

Good

Over: HAMILTON-STORY 1 OPEN DD

085 24 22 01, Story, IA

Built 2012 Load: 41.6 t ADT: 1,427

EAGLE AVE

Good

Over: SMALL STREAM

071311102, Union, IA

Built 2015 Load: 41.6 t ADT: 15

W55 WAYLAND RD

Good

Over: W FORK CROOKED CREEK

074070504, Washington, IA

Built 2002 Load: 41.6 t ADT: 1,720

CO RD V68

Good

Over: SMALL CREEK

000000000, Winneshiek, IA

Built 2009 Load: 41.6 t ADT: 649

D16 OTTERVILLE

Good

Over: SMALL STREAM

089092801, Buchanan, IA

Built 2019 Load: 41.7 t ADT: 805

FM

Good

Over: E FORK WAPSIPINICON

095120608, Chickasaw, IA

Built 1999 Load: 41.7 t ADT: 383

LOCAL

Good

Over: EAST WAPSIPINICON

095122201, Chickasaw, IA

Built 2002 Load: 41.7 t ADT: 104

Z36 380TH AVE

Good

Over: SMALL STREAM

082E51402, Clinton, IA

Built 2018 Load: 41.7 t ADT: 1,300

LOCAL

Good

Over: LITTLE SIOUX RIVER

098372301, Dickinson, IA

Built 2004 Load: 41.7 t ADT: 61

130 TH

Good

Over: HARDIN CREEK

085312301, Greene, IA

Built 1988 Load: 41.7 t ADT: 21

LOCAL

Good

Over: TIPTON CREEK

087210701, Hardin, IA

Built 1991 Load: 41.7 t ADT: 11

261ST AVE

Good

Over: BRUSH CREEK

085E31404, Jackson, IA

Built 2008 Load: 41.7 t ADT: 15

FM

Good

Over: BIG CEDAR CREEK

072113602, Jefferson, IA

Built 1983 Load: 41.7 t ADT: 40

FM

Good

Over: LOST CREEK

068030703, Lee, IA

Built 2000 Load: 41.7 t ADT: 650

FM

Good

Over: CLEAR CREEK

082200805, Marshall, IA

Built 2006 Load: 41.7 t ADT: 265

MEMORIAL DR

Good

Over: BRADDY CREEK

IOWA VETERANS HOME, Marshall, IA

Built 1995 Load: 41.7 t

490TH

Good

Over: LITTLE CEDAR RIVER

100161903, Mitchell, IA

Built 1989 Load: 41.7 t ADT: 49

FM

Good

Over: PINE CREEK

077E10702, Muscatine, IA

Built 2008 Load: 41.7 t ADT: 200

FM

Good

Over: MUD CREEK

078E10404, Muscatine, IA

Built 2002 Load: 41.7 t ADT: 620

112TH ST

Good

Over: SUGAR CREEK

078021005, Muscatine, IA

Built 2000 Load: 41.7 t ADT: 733

FM

Good

Over: MILL CREEK

094411502, O'Brien, IA

Built 2000 Load: 41.7 t ADT: 828

LOCAL

Good

Over: SIX MILE CREEK

094482401, Sioux, IA

Built 1997 Load: 41.7 t ADT: 40

120TH ST

Good

Over: HARDIN-STORY DD 1

.46 Mi E of NW Cor., Story, IA

Built 2018 Load: 41.7 t ADT: 11

280TH ST

Good

Over: MIDDLE NODAWAY RIVER

0.8 mi E of N72 on 280th, Adair, IA

Built 2023 Load: 41.8 t ADT: 15

LOCAL

Good

Over: NINE MILE CREEK

076332790, Adair, IA

Built 2004 Load: 41.8 t ADT: 11

LOCAL

Good

Over: MUD CREEK

084100701, Benton, IA

Built 2010 Load: 41.8 t ADT: 20

25TH AVE

Good

Over: MUD CREEK

085102818, Benton, IA

Built 2013 Load: 41.8 t ADT: 78

YORK AVE

Good

Over: SMALL STREAM

S13 T88N R07W, Buchanan, IA

Built 2017 Load: 41.8 t ADT: 69

V62 BAXTER AVE

Good

Over: SMALL STREAM

089100802, Buchanan, IA

Built 2018 Load: 41.8 t ADT: 1,365

LOCAL

Good

Over: DRAINAGE DITCH

090353602, Buena Vista, IA

Built 2007 Load: 41.8 t ADT: 26

280TH ST

Good

Over: MCCLURE CREEK

090150503, Butler, IA

Built 2011 Load: 41.8 t ADT: 108

LOCAL

Good

Over: PRAIRIE CREEK 319

086341102, Calhoun, IA

Built 2007 Load: 41.8 t ADT: 34

TAYLOR AVE

Good

Over: YANKEE RUN CREEK

081010501, Cedar, IA

Built 2008 Load: 41.8 t ADT: 71

CHARLES AVE

Good

Over: BR CLEAR CR

082042804, Cedar, IA

Built 2016 Load: 41.8 t ADT: 70

LOCAL-510TH ST.

Good

Over: RAILROAD CREEK

092402101, Cherokee, IA

Built 2009 Load: 41.8 t ADT: 71

KENWOOD AVE

Good

Over: EAST WAPSIPINICON RIVER

096132402, Chickasaw, IA

Built 2022 Load: 41.8 t ADT: 187

LOCAL

Good

Over: LOCAL CREEK

072272401, Clarke, IA

Built 2009 Load: 41.8 t ADT: 29

ROBIN STREET

Good

Over: HANNER CREEK

073262101, Clarke, IA

Built 2009 Load: 41.8 t ADT: 5

340TH ST

Good

Over: OCHEYEDAN RIVER

096380505, Clay, IA

Built 2008 Load: 41.8 t ADT: 30

DOGWOOD AVE

Good

Over: STREAM

.1 M S 100th st, Clayton, IA

Built 2020 Load: 41.8 t ADT: 16

W 11TH ST

Good

Over: SILVER CREEK

000000000, Clinton, IA

Built 1990 Load: 41.8 t ADT: 8,900

230TH AVENUE

Good

Over: BARBER CREEK

081E32902, Clinton, IA

Built 2010 Load: 41.8 t ADT: 410

X 99

Good

Over: YELLOW SPRING CREEK

071023504, Des Moines, IA

Built 2008 Load: 41.8 t ADT: 970

COTTINGHAM RD

Good

Over: S FORK CATFISH CREEK

089E13607, Dubuque, IA

Built 2017 Load: 41.8 t ADT: 412

N AVE

Good

Over: VOLGA RIVER

000000000, Fayette, IA

Built 2010 Load: 41.8 t ADT: 29

B30 150TH ST

Good

Over: FLOOD CREEK

096181401, Floyd, IA

Built 2016 Load: 41.8 t ADT: 1,159

LOCAL

Good

Over: CREEK

094153301, Floyd, IA

Built 2008 Load: 41.8 t ADT: 26

280TH ST

Good

Over: FLOOD CREEK

094162001, Floyd, IA

Built 2011 Load: 41.8 t ADT: 39

HOLLY AVE

Good

Over: FLOOD CREEK

096173206, Floyd, IA

Built 2014 Load: 41.8 t ADT: 20

S43 LINCOLN ST

Good

Over: BAILEYE CREEK

93200902, Franklin, IA

Built 2023 Load: 41.8 t ADT: 709

Showing 14,651-14,700 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.