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

195TH ST

Good

Over: SILVER CREEK (WEST)

082E32207, Clinton, IA

Built 1917 Load: 40.4 t ADT: 26

S 124TH AVE E

Good

Over: SMALL STREAM

078183405, Jasper, IA

Built 2013 Load: 40.4 t ADT: 80

RODEO AVE E

Good

Over: COAL CREEK

078192803, Jasper, IA

Built 2014 Load: 40.4 t ADT: 16

W 132ND ST S

Good

Over: SMALL STREAM

079210902, Jasper, IA

Built 2013 Load: 40.4 t ADT: 25

FM

Good

Over: STREAM

075180903, Marion, IA

Built 1989 Load: 40.4 t ADT: 160

320TH STREET

Good

Over: NODAWAY RIVER

067363003, Page, IA

Built 2005 Load: 40.4 t ADT: 255

LOCAL

Good

Over: NORTH RIVER

077230802, Warren, IA

Built 1984 Load: 40.4 t ADT: 154

LOCAL

Good

Over: LOCUST CR

068203203, Wayne, IA

Built 2003 Load: 40.4 t ADT: 20

FM

Good

Over: BOONE RIVER

091262903, Wright, IA

Built 1990 Load: 40.4 t ADT: 898

LOCAL

Good

Over: WALNUT CREEK

069180303, Appanoose, IA

Built 2009 Load: 40.5 t ADT: 62

FM

Good

Over: WAPSIPINICON RIVER

092120203, Bremer, IA

Built 1998 Load: 40.5 t ADT: 177

HAWTHORNE AVE

Good

Over: STREAM

092132002, Bremer, IA

Built 2022 Load: 40.5 t ADT: 39

120TH ST

Good

Over: PLUM CREEK

093121401, Bremer, IA

Built 2008 Load: 40.5 t ADT: 39

185TH ST

Good

Over: SMALL STREAM

089091703, Buchanan, IA

Built 2018 Load: 40.5 t ADT: 62

LOCAL

Good

Over: SMALL STREAM

092172102, Butler, IA

Built 2004 Load: 40.5 t ADT: 49

WB I-80

Good

Over: TROUBLESOME CREEK

4.5 MI. E OF US 71, Cass, IA

Built 2003 Load: 40.5 t ADT: 11,500

FM

Good

Over: W BR WAPSIPINICON CREEK

079042001, Cedar, IA

Built 2009 Load: 40.5 t ADT: 160

LOCAL

Good

Over: ROCK CREEK

082032604, Cedar, IA

Built 2009 Load: 40.5 t ADT: 34

V56 UNION

Good

Over: LITTLE TURKEY

096111002, Chickasaw, IA

Built 2008 Load: 40.5 t ADT: 717

ELK ST

Good

Over: BEE CREEK

071261501, Clarke, IA

Built 2011 Load: 40.5 t ADT: 79

LOCAL

Good

Over: BEE CREEK

071262101, Clarke, IA

Built 2009 Load: 40.5 t ADT: 15

Y-44

Good

Over: CALAMUS CREEK

00000, Clinton, IA

Built 2011 Load: 40.5 t ADT: 730

125TH STREET

Good

Over: ELK RIVER

083E61703, Clinton, IA

Built 2018 Load: 40.5 t ADT: 21

IA 136

Good

Over: CAR BARN CREEK

IN CITY OF CLINTON, Clinton, IA

Built 2016 Load: 40.5 t ADT: 5,200

US 30

Good

Over: DRAINAGE DITCH

0.5 mi N of Ia. 37, Crawford, IA

Built 2015 Load: 40.5 t ADT: 3,180

MINES OF SPAIN

Good

Over: CATFISH CREEK

IN MINES OF SPAIN ST. PK., Dubuque, IA

Built 1993 Load: 40.5 t

235TH ST

Good

Over: MULE SLOUGH

068431809, Fremont, IA

Built 2013 Load: 40.5 t ADT: 26

LOCAL

Good

Over: BLACKHAWK CREEK

087160705, Grundy, IA

Built 1976 Load: 40.5 t ADT: 196

260TH ST

Good

Over: DRAINAGE DITCH

088232501, Hamilton, IA

Built 2017 Load: 40.5 t ADT: 34

130TH ST

Good

Over: MID BR BOONE RIVER DD 8

094262401, Hancock, IA

Built 2020 Load: 40.5 t ADT: 10

US 20

Good

Over: DRAINAGE

0.3 MILE E OF JCT SR S56, Hardin, IA

Built 2003 Load: 40.5 t ADT: 9,200

310TH ST

Good

Over: FISH CREEK

070062208, Henry, IA

Built 2012 Load: 40.5 t ADT: 35

FM

Good

Over: BNSF RR

071060802, Henry, IA

Built 2010 Load: 40.5 t ADT: 1,120

BELL AVE

Good

Over: BR WAPSIPINICON RIV

097140502, Howard, IA

Built 2005 Load: 40.5 t ADT: 21

310TH ST

Good

Over: CREEK

086391901, Ida, IA

Built 2020 Load: 40.5 t ADT: 62

HIGH BRIDGE RD

Good

Over: SMALL STREAM

087E40403, Jackson, IA

Built 2020 Load: 40.5 t ADT: 137

E 60TH ST S

Good

Over: STREAM

079180504, Jasper, IA

Built 2004 Load: 40.5 t ADT: 16

220TH ST

Good

Over: CREEK

071110403, Jefferson, IA

Built 2016 Load: 40.5 t ADT: 40

FM

Good

Over: LICK CREEK

071112506, Jefferson, IA

Built 2010 Load: 40.5 t ADT: 740

MONROE AVE

Good

Over: FLOYD RIVER OVERFLOW

097422902, O'Brien, IA

Built 2020 Load: 40.5 t ADT: 518

IA 3

Good

Over: DRAINAGE DITCH

1.6 mi. W of jct. SR K42, Plymouth, IA

Built 2020 Load: 40.5 t ADT: 1,420

OTTER AVE

Good

Over: DEEP CREEK

092440502, Plymouth, IA

Built 2007 Load: 40.5 t ADT: 100

NB US 65

Good

Over: DRAINAGE DITCH

4.4 MILES N OF N JCT I-80, Polk, IA

Built 1979 Load: 40.5 t ADT: 8,200

NW 128TH ST SB

Good

Over: WALNUT CREEK

079253200, Polk, IA

Built 1998 Load: 40.5 t ADT: 7,065

NW 128TH ST NB

Good

Over: WALNUT CREEK

079253200, Polk, IA

Built 2007 Load: 40.5 t ADT: 6,875

LOCAL

Good

Over: M FK GRAND RIVER

068302601, Ringgold, IA

Built 2009 Load: 40.5 t ADT: 11

FM

Good

Over: GOOSEBERRY CREEK

069292701, Ringgold, IA

Built 2009 Load: 40.5 t ADT: 15

F16

Good

Over: MILL CREEK

ON F-16 NORTH OF DOGWOOD, Shelby, IA

Built 2017 Load: 40.5 t ADT: 79

290TH ST

Good

Over: STREAM

1675 east of Dogwood, Sioux, IA

Built 2015 Load: 40.5 t ADT: 50

660TH AVE

Good

Over: ROCK CREEK

0.4 Mi N of IA 210, Story, IA

Built 2016 Load: 40.5 t ADT: 100

Showing 14,351-14,400 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.