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

FM-JUNIPER ROAD

Good

Over: KEG CREEK

076422507, Pottawattamie, IA

Built 1986 Load: 27.3 t ADT: 40

LOCAL

Good

Over: SIX MILE CREEK

094470701, Sioux, IA

Built 1983 Load: 27.3 t ADT: 45

FM

Good

Over: WEST BRANCH FLOYD RIVER

095452301, Sioux, IA

Built 1983 Load: 27.3 t ADT: 120

P33 HENRY WALLACE

Good

Over: THREE MILE CREEK

74301807, Adair, IA

Built 1989 Load: 27.4 t ADT: 1,374

FM 1980 110TH

Good

Over: EAST IOWA RIVER

094233103, Hancock, IA

Built 1957 Load: 27.4 t ADT: 399

US 61

Good

Over: STREAM

3.9 MI. N OF N JCT. US 30, Clinton, IA

Built 1996 Load: 27.5 t ADT: 10,600

US 61

Good

Over: STREAM

0.5 MI. N OF JCT. IA 136, Clinton, IA

Built 1996 Load: 27.5 t ADT: 9,800

US 65

Good

Over: STREAM

2.4 MILES N OF JCT SR E18, Story, IA

Built 1990 Load: 27.5 t ADT: 1,440

NAVAHO AVE

Good

Over: WATERWAY

092123202, Bremer, IA

Built 2015 Load: 27.6 t ADT: 39

LOCAL SEC RD

Good

Over: DRY RUN

094400502, O'Brien, IA

Built 1949 Load: 27.6 t ADT: 21

E BENNINGTON RD

Good

Over: TRIB TO CRANE CREEK

90-12-24-01-10, Black Hawk, IA

Built 1984 Load: 27.7 t ADT: 20

US 71

Good

Over: STREAM

0.5 mi S of jct US 30, Carroll, IA

Built 2000 Load: 27.7 t ADT: 5,600

390TH ST

Good

Over: PRAIRIE CREEK

095370401, Clay, IA

Built 2008 Load: 27.7 t ADT: 50

FM

Good

Over: ROCK CREEK

080243204, Polk, IA

Built 1981 Load: 27.7 t ADT: 1,752

DUBUQUE RD(WB)

Good

Over: BLOWERS CREEK

CITY BRIDGE NO. 24, Black Hawk, IA

Built 1991 Load: 27.8 t ADT: 4,208

V43

Good

Over: WATERWAY

091121502, Bremer, IA

Built 2007 Load: 27.8 t ADT: 69

IA 38

Good

Over: PLUM CREEK

1.9 mi. N of SR D47, Delaware, IA

Built 1992 Load: 27.8 t ADT: 1,030

IA 62

Good

Over: LITTLE MILL CREEK

0.1 mi. S of Jct. SR D61, Jackson, IA

Built 1976 Load: 27.8 t ADT: 1,100

FM

Good

Over: ROCK CREEK

080171703, Jasper, IA

Built 2004 Load: 27.8 t ADT: 90

FM

Good

Over: WHITE BREAST CREEK

075201902, Marion, IA

Built 1984 Load: 27.8 t ADT: 60

FM

Good

Over: TRIBUTARY TO NODAWAY

071362102, Montgomery, IA

Built 2010 Load: 27.8 t ADT: 79

IA 60 NB

Good

Over: DRAINAGE

1.1 mi. S of SR L36, Osceola, IA

Built 2004 Load: 27.8 t ADT: 5,100

LOCAL

Good

Over: STREAM

0.9 mi W of N54 on 210th, Adair, IA

Built 2004 Load: 27.9 t ADT: 21

US 61

Good

Over: DD #15

2.4 MI. S OF S Jct. US 30, Clinton, IA

Built 1981 Load: 27.9 t ADT: 17,600

US 59 & IA 141

Good

Over: DRAINAGE DITCH

1.8 mi. S of S jct. US 30, Crawford, IA

Built 1986 Load: 27.9 t ADT: 4,050

LOCAL

Good

Over: ELK CREEK

082372802, Crawford, IA

Built 2005 Load: 27.9 t ADT: 41

81ST STREET

Good

Over: CREEK

000000000, Dallas, IA

Built 2003 Load: 27.9 t ADT: 21

250TH ST

Good

Over: SMALL STREAM

094100201, Fayette, IA

Built 1999 Load: 27.9 t ADT: 39

260 STREET

Good

Over: M.V.DD#10

068423101, Fremont, IA

Built 1983 Load: 27.9 t ADT: 26

LOCAL

Good

Over: DRAINAGE DITCH

069433402, Fremont, IA

Built 1985 Load: 27.9 t ADT: 15

FM

Good

Over: SUGAR CREEK

068061303, Lee, IA

Built 1985 Load: 27.9 t ADT: 370

STARLING AVE

Good

Over: WILLOW CREEK

094 40 16 02 10, O'Brien, IA

Built 2014 Load: 27.9 t ADT: 26

SILVER AVE

Good

Over: WILLOW CREEK

094401902, O'Brien, IA

Built 2017 Load: 27.9 t ADT: 40

480TH ST

Good

Over: WILLOW CREEK

094 40 20 01 10, O'Brien, IA

Built 2018 Load: 27.9 t ADT: 15

SORREL AVE

Good

Over: WILLOW CREEK

094402002, O'Brien, IA

Built 2017 Load: 27.9 t ADT: 30

420TH ST

Good

Over: MCCREATH CREEK

095392101, O'Brien, IA

Built 2015 Load: 27.9 t ADT: 34

FM-340TH STREET

Good

Over: SILVER CREEK

075413502, Pottawattamie, IA

Built 1982 Load: 27.9 t ADT: 79

FM

Good

Over: SMALL STREAM

079E21604, Scott, IA

Built 1987 Load: 27.9 t ADT: 100

US 59

Good

Over: DRAINAGE

2.5 MI. N OF JCT. IA 37, Shelby, IA

Built 1970 Load: 27.9 t ADT: 3,020

N RAYMOND RD

Good

Over: TRIB TO ELK RUN CREEK

89-12-01-02-10, Black Hawk, IA

Built 1996 Load: 28.0 t ADT: 1,561

I-380

Good

Over: MUD CREEK

1.4 Mi. S OF Jct. SR V65, Buchanan, IA

Built 1983 Load: 28.0 t ADT: 17,700

MONROE AVE

Good

Over: STREAM

082020602, Cedar, IA

Built 2006 Load: 28.0 t ADT: 40

FIG AVE

Good

Over: TRIB FABIUS CR

068153604, Davis, IA

Built 2017 Load: 28.0 t ADT: 11

WB US 20

Good

Over: S. FK IOWA RIVER

1.0 MILE EAST OF SR S27, Hardin, IA

Built 1990 Load: 28.0 t ADT: 4,650

IA 38

Good

Over: SANDY CREEK

2.6 MI. S OF SR D-47., Jones, IA

Built 1973 Load: 28.0 t ADT: 2,380

LOCAL

Good

Over: CREEK

071193503, Monroe, IA

Built 2001 Load: 28.0 t ADT: 30

J-20/137TH ST

Good

Over: WEST NODAWAY RIVER

070362011, Page, IA

Built 1942 Load: 28.0 t ADT: 499

FM

Good

Over: LITTLE WAPSIPINICON RVR

096132903, Chickasaw, IA

Built 1980 Load: 28.1 t ADT: 88

33RD AVE SW

Good

Over: UP AND CRANDIC RR

000000000, Linn, IA

Built 2006 Load: 28.1 t ADT: 10,700

FM

Good

Over: FOURMILE CREEK

080232918, Polk, IA

Built 1986 Load: 28.1 t ADT: 1,047

Showing 9,801-9,850 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.