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

US 67

Good

Over: E. PIGEON CREEK

4.0 mi. S of Jct. I-80, Scott, IA

Built 1995 Load: 29.0 t ADT: 9,800

LOCAL

Good

Over: SMALL STREAM

097450502, Sioux, IA

Built 1986 Load: 29.0 t ADT: 34

BEACH ROAD

Good

Over: COLLEGE CREEK

0.1 mi. N of Lincolnway, Story, IA

Built 1973 Load: 29.0 t ADT: 4,878

US 20

Good

Over: DRAINAGE DITCH NO 1 & 54

2.4 mi. E of Jct. SR N28, Calhoun, IA

Built 2010 Load: 29.1 t ADT: 5,900

FA-BROTHERS AVE

Good

Over: NISHNABOTNA RIVER

073400901, Mills, IA

Built 1986 Load: 29.1 t ADT: 349

DEVILS GLEN RD

Good

Over: CROW CREEK

Bettendorf, IA, Scott, IA

Built 1999 Load: 29.1 t ADT: 4,610

CAMPUS ST

Good

Over: UNIV BR DRY RUN

BTWN 20TH & 22ND STREETS, Black Hawk, IA

Built 2019 Load: 29.2 t ADT: 1,493

FAIRVIEW AVE

Good

Over: CREEK

092141202, Bremer, IA

Built 2011 Load: 29.2 t ADT: 29

IA 130

Good

Over: STREAM

IN BENNETT, Cedar, IA

Built 1996 Load: 29.2 t ADT: 900

SPICER AVE

Good

Over: ROCK CREEK

081011904, Cedar, IA

Built 2016 Load: 29.2 t ADT: 35

KING AVE

Good

Over: ROCK CREEK

082032606, Cedar, IA

Built 2012 Load: 29.2 t ADT: 34

FM 310TH ST

Good

Over: BUFFALO CREEK

087061901, Delaware, IA

Built 1985 Load: 29.2 t ADT: 49

US 59

Good

Over: ROCK CREEK

1.6 mi. N of jct. SR J-64, Fremont, IA

Built 1985 Load: 29.2 t ADT: 1,390

297TH AVE

Good

Over: BRUSH CREEK

085E32410, Jackson, IA

Built 2019 Load: 29.2 t ADT: 49

WAPSIPINICON SP

Good

Over: DUTCH CREEK

IN WAPSIPINICON ST. PARK, Jones, IA

Built 1995 Load: 29.2 t

JORDANS GROVE RD

Good

Over: WAPSIPINICON RIVER

085061302, Linn, IA

Built 2020 Load: 29.2 t ADT: 371

LOCAL

Good

Over: WATERMAN CREEK

097391801, O'Brien, IA

Built 1978 Load: 29.2 t ADT: 15

IA 60

Good

Over: DRAINAGE

1.2 mi. S of jct. SR A34, Osceola, IA

Built 2004 Load: 29.2 t ADT: 5,400

FM

Good

Over: CREEK

079242204, Polk, IA

Built 1974 Load: 29.2 t ADT: 3,426

FM

Good

Over: BRANCH DES MOINES RIVER

079242206, Polk, IA

Built 1974 Load: 29.2 t ADT: 3,685

FM

Good

Over: MIDDLE BRANCH 102 RIVER

069340508, Taylor, IA

Built 1986 Load: 29.2 t ADT: 15

IA 1

Good

Over: CEDAR CREEK

3.4 mi. S of S Jct. IA 92, Washington, IA

Built 1987 Load: 29.2 t ADT: 2,340

I-380

Good

Over: STREAM

2.5 MI. N OF Jct. SR V65, Black Hawk, IA

Built 1984 Load: 29.3 t ADT: 17,100

US 218

Good

Over: TRIB. TO CEDAR RIVER

1.5 mi. N of Jct. IA 188, Bremer, IA

Built 2002 Load: 29.3 t ADT: 7,900

US 71

Good

Over: LONE TREE CREEK

0.1 mi. S of Jct. SR G35, Cass, IA

Built 1971 Load: 29.3 t ADT: 2,830

FM

Good

Over: UNNAMED STREAM

076121601, Keokuk, IA

Built 2003 Load: 29.3 t ADT: 45

180TH ST

Good

Over: STREAM

078143602, Poweshiek, IA

Built 2016 Load: 29.3 t ADT: 10

505TH AVE

Good

Over: EAST BUCK CREEK

078151703, Poweshiek, IA

Built 2022 Load: 29.3 t ADT: 11

LOCAL

Good

Over: BRANCH OF RICHLAND CREEK

082142005, Tama, IA

Built 1945 Load: 29.3 t ADT: 5

LOCAL

Good

Over: BUFFALO CREEK

082101702, Benton, IA

Built 1997 Load: 29.4 t ADT: 40

QUAIL AVE

Good

Over: MIDDLE RACCON RIVER

084342602, Carroll, IA

Built 2000 Load: 29.4 t ADT: 180

180TH AVE.

Good

Over: CREEK

083E21602, Clinton, IA

Built 1989 Load: 29.4 t ADT: 26

ORCHARD AVE

Good

Over: HARDIN CREEK

084303304, Greene, IA

Built 1983 Load: 29.4 t ADT: 79

LOCAL

Good

Over: SOUTH FORK BEAVER CREEK

089173302, Grundy, IA

Built 1985 Load: 29.4 t ADT: 33

W AVE

Good

Over: UNAMED CREEK

093102102, Fayette, IA

Built 2004 Load: 29.5 t ADT: 884

IA 16

Good

Over: BRANCH SUGAR CREEK

1.1 mi. E of Jct. US 218., Lee, IA

Built 1987 Load: 29.5 t ADT: 1,220

FM

Good

Over: FLOYD RIVER

097410802, O'Brien, IA

Built 1986 Load: 29.5 t ADT: 489

LOCAL

Good

Over: W FK GRAND RIVER

070311601, Ringgold, IA

Built 1996 Load: 29.5 t ADT: 26

FM

Good

Over: SMALL STREAM

097092011, Winneshiek, IA

Built 2007 Load: 29.5 t ADT: 501

NB IA 27

Good

Over: CEDAR RIVER & RR

0.8 Mi. S OF JCT. US 218, Black Hawk, IA

Built 1995 Load: 29.6 t ADT: 7,550

OXEN TRAIL

Good

Over: N CHEQUEST LAKE CREEK

070132803, Davis, IA

Built 2018 Load: 29.6 t ADT: 34

LOCAL

Good

Over: CREEK

081341902, Audubon, IA

Built 1940 Load: 29.7 t ADT: 30

160TH AVE

Good

Over: SPRING CREEK

096370702, Clay, IA

Built 1981 Load: 29.7 t ADT: 40

LOCAL

Good

Over: SMALL STREAM

078272905, Dallas, IA

Built 1974 Load: 29.7 t ADT: 15

ACORN AVE

Good

Over: FOX RIVER SYSTEM

68150604, Davis, IA

Built 2015 Load: 29.7 t ADT: 20

270TH AVE

Good

Over: LOST BRANCH CREEK

071213602, Lucas, IA

Built 2013 Load: 29.7 t ADT: 30

FM C-44

Good

Over: DRY BRANCH

091442101, Plymouth, IA

Built 1998 Load: 29.7 t ADT: 150

FM RD F32

Good

Over: SMALL STREAM

802437, Shelby, IA

Built 1982 Load: 29.7 t ADT: 29

270TH ST

Good

Over: SO BRANCH SALT CREEK

084143401, Tama, IA

Built 2014 Load: 29.7 t ADT: 11

MINERAL CREEK D

Good

Over: MINERAL CREEK

099061303, Allamakee, IA

Built 2013 Load: 29.8 t ADT: 15

Showing 9,951-10,000 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.