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: DRAINAGE DITCH 14

091240801, Wright, IA

Built 2002 Load: 32.7 t ADT: 51

LOCAL

Good

Over: STREAM

091251502, Wright, IA

Built 2008 Load: 32.7 t ADT: 62

FM

Good

Over: DRAINAGE DITCH 9

091253003, Wright, IA

Built 2003 Load: 32.7 t ADT: 1,387

250TH ST

Good

Over: STREAM

091261707, Wright, IA

Built 2004 Load: 32.7 t ADT: 92

160TH ST

Good

Over: CREEK

092230201, Wright, IA

Built 2021 Load: 32.7 t ADT: 15

LOCAL

Good

Over: DD #99

092232703, Wright, IA

Built 2008 Load: 32.7 t ADT: 21

FM

Good

Over: SMALL STREAM

092232704, Wright, IA

Built 2008 Load: 32.7 t ADT: 61

LOCAL

Good

Over: WHITE FOX CREEK

092243201, Wright, IA

Built 2006 Load: 32.7 t ADT: 82

210TH ST

Good

Over: DD #36

092253501, Wright, IA

Built 2010 Load: 32.7 t ADT: 51

FM

Good

Over: DRAINAGE DITCH 107

093252902, Wright, IA

Built 2007 Load: 32.7 t ADT: 469

NORTH DAVIS AVE

Good

Over: WRIGHT CO. DRAIN DITCH

091262202, Wright, IA

Built 2004 Load: 32.7 t ADT: 25

FM GABRIAL AV

Good

Over: LIME CREEK

088103602, Buchanan, IA

Built 1976 Load: 32.8 t ADT: 59

220TH ST

Good

Over: ROCK RUN CREEK

080030301, Cedar, IA

Built 1975 Load: 32.8 t ADT: 140

H48 DOYLE ST

Good

Over: BEE CREEK

071262203, Clarke, IA

Built 2017 Load: 32.8 t ADT: 26

ROBIN ST

Good

Over: LOCAL CREEK

0732711, Clarke, IA

Built 2018 Load: 32.8 t ADT: 11

104TH AVE

Good

Over: LIZARD CREEK

081E11906, Clinton, IA

Built 1994 Load: 32.8 t ADT: 73

340TH AVENUE

Good

Over: CHERRY CREEK

081E51804, Clinton, IA

Built 1998 Load: 32.8 t ADT: 30

170TH ST.

Good

Over: DRAINAGE

082E20801, Clinton, IA

Built 1991 Load: 32.8 t ADT: 21

150TH ST

Good

Over: CREEK

083E63201, Clinton, IA

Built 2007 Load: 32.8 t ADT: 62

IA 64

Good

Over: DEEP CREEK

0.3 mi. E of Jct. SR Z20, Jackson, IA

Built 1984 Load: 32.8 t ADT: 2,290

EAST 36TH ST N

Good

Over: SMALL STREAM

081191304, Jasper, IA

Built 2017 Load: 32.8 t ADT: 82

LOCAL

Good

Over: STREAM

076120805, Keokuk, IA

Built 2017 Load: 32.8 t ADT: 40

FM

Good

Over: PAINTER CREEK

067052005, Lee, IA

Built 1972 Load: 32.8 t ADT: 1,400

FM

Good

Over: HONEY CREEK

071202305, Lucas, IA

Built 2006 Load: 32.8 t ADT: 20

570TH ST

Good

Over: BRANCH OF LONG BRANCH CR

073210805, Lucas, IA

Built 2012 Load: 32.8 t ADT: 41

FM

Good

Over: BUCKLEY CREEK(MIDDLE BR)

077170404, Mahaska, IA

Built 1984 Load: 32.8 t ADT: 1,130

LOCAL

Good

Over: WALNUT CREEK

071393003, Montgomery, IA

Built 1978 Load: 32.8 t ADT: 20

FM-JUNIPER ROAD

Good

Over: MOSQUITO CREEK

076422903, Pottawattamie, IA

Built 1970 Load: 32.8 t ADT: 159

LOCAL

Good

Over: LITTLE BEAR CREEK

080142902, Poweshiek, IA

Built 2004 Load: 32.8 t ADT: 20

US 63

Good

Over: RICHLAND CREEK

3.1 MILES SOUTH OF SR E64, Tama, IA

Built 1978 Load: 32.8 t ADT: 2,440

SB US 169

Good

Over: LIZARD CREEK

0.3 mi. S of jct. IA 7, Webster, IA

Built 2011 Load: 32.8 t ADT: 4,450

390TH ST

Good

Over: WILLOW CREEK

095380601, Clay, IA

Built 2008 Load: 32.9 t ADT: 5

330TH ST

Good

Over: LITTLE MEADOW CREEK

096360403, Clay, IA

Built 1975 Load: 32.9 t ADT: 103

190TH AVE

Good

Over: CALAMUS CREEK

081E21002, Clinton, IA

Built 1996 Load: 32.9 t ADT: 104

LOCAL

Good

Over: CREEK

089402002, Ida, IA

Built 2010 Load: 32.9 t ADT: 11

210TH ST

Good

Over: SMALL STREAM

072303101, Union, IA

Built 2012 Load: 32.9 t ADT: 26

4TH AVE SW

Good

Over: SMALL STREAM

Int 4th Ave/3rd St SW, Bremer, IA

Built 2015 Load: 33.0 t ADT: 283

2ND ST SW

Good

Over: SMALL STREAM

Int of 6th Ave/2st SW, Bremer, IA

Built 2015 Load: 33.0 t ADT: 173

3RD AVE SW

Good

Over: DRY RUN CREEK

Int 3rd St/3rd Ave SW, Bremer, IA

Built 2015 Load: 33.0 t ADT: 253

5TH AVE SW

Good

Over: DRY RUN CREEK

0.2 Mi E of 4th St SW, Bremer, IA

Built 2015 Load: 33.0 t ADT: 501

1ST AVE NW

Good

Over: DRY RUN CREEK

100' E of 6th Ave NW, Bremer, IA

Built 2015 Load: 33.0 t ADT: 283

FM

Good

Over: WAPSIPINICON RIVER

089101309, Buchanan, IA

Built 1999 Load: 33.0 t ADT: 216

NOLAN AVE

Good

Over: WAPSIPINICON RIVER

088083204, Buchanan, IA

Built 1996 Load: 33.0 t ADT: 135

T23 HOLLY AVE

Good

Over: SMALL STREAM

090172901, Butler, IA

Built 2018 Load: 33.0 t ADT: 137

180TH STREET

Good

Over: SMALL STREAM

Int Birch Ave & 180th St., Butler, IA

Built 2022 Load: 33.0 t ADT: 26

LOCAL

Good

Over: CAMP CREEK

088342801, Calhoun, IA

Built 1980 Load: 33.0 t ADT: 20

FM

Good

Over: WILLOW CREEK

083332301, Carroll, IA

Built 1975 Load: 33.0 t ADT: 170

X 42 INDIAN AVE

Good

Over: WAPSINONOC CREEK

079033302, Cedar, IA

Built 2019 Load: 33.0 t ADT: 60

JONQUIL

Good

Over: BEAVER DAM CREEK

095211502, Cerro Gordo, IA

Built 1978 Load: 33.0 t ADT: 34

19TH ST SE

Good

Over: MASON CREEK

0.1 mile East of Kentucky, Cerro Gordo, IA

Built 2016 Load: 33.0 t ADT: 281

Showing 12,301-12,350 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.