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

COUNTY RD E-45

Fair

Over: SMALL CREEK

083020805, Jones, IA

Built 1971 Load: 40.2 t ADT: 422

US 218 NB

Fair

Over: BIG SUGAR CREEK

AT JCT. IA 16, Lee, IA

Built 1970 Load: 40.2 t ADT: 4,550

IDELWOOD ROAD

Fair

Over: MIDDLE SILVER CREEK

075410301, Pottawattamie, IA

Built 1978 Load: 40.2 t ADT: 34

FM RD M56

Fair

Over: SMALL STREAM

080380302, Shelby, IA

Built 1989 Load: 40.2 t ADT: 34

US 30

Fair

Over: DRAINAGE DITCH

1.2 mi. E of Jct. SR Y68, Clinton, IA

Built 1974 Load: 40.3 t ADT: 9,400

LOC 80TH AVE

Fair

Over: CALAMUS CREEK

097291702, Kossuth, IA

Built 1991 Load: 40.3 t ADT: 15

FM

Fair

Over: CLANTON CREEK

075262207, Madison, IA

Built 1995 Load: 40.3 t ADT: 1,055

LOCAL

Fair

Over: STREAM

068171604, Appanoose, IA

Built 1900 Load: 40.4 t ADT: 51

160TH AVE

Fair

Over: CEDAR FORK CREEK

071270801, Des Moines, IA

Built 2016 Load: 40.4 t ADT: 91

WB US 34

Fair

Over: BNSF RR

0.5 MI E OF E JCT I-29, Mills, IA

Built 1973 Load: 40.4 t ADT: 5,900

180TH AVE

Fair

Over: CREEK

.25 MI north of 107th St., Winneshiek, IA

Built 2012 Load: 40.4 t ADT: 70

US 75 SB

Fair

Over: FLOYD RIVER

5.3 mi. N of US 20/IA 12, Woodbury, IA

Built 1999 Load: 40.4 t ADT: 5,650

FM

Fair

Over: BRANCH, NODAWAY RIVER

077333402, Adair, IA

Built 2008 Load: 40.5 t ADT: 349

US 20

Fair

Over: DRY CREEK

0.6 MI. W OF Jct. SR W40, Buchanan, IA

Built 1979 Load: 40.5 t ADT: 8,300

IA 2

Fair

Over: WEST ELK CREEK

6.7 mi. W of Jct. I-35, Decatur, IA

Built 1985 Load: 40.5 t ADT: 930

LOCAL

Fair

Over: CREEK

0993435, Emmet, IA

Built 1990 Load: 40.5 t ADT: 34

LOCAL

Fair

Over: BR SILVER CREEK

088391901, Ida, IA

Built 1999 Load: 40.5 t ADT: 15

LOCAL

Fair

Over: SMALL CREEK

085E40908, Jackson, IA

Built 1999 Load: 40.5 t ADT: 50

LOCAL

Fair

Over: CROW CREEK

075212001, Marion, IA

Built 1997 Load: 40.5 t ADT: 51

LOCAL ROAD

Fair

Over: BRANCH OF TARKIO CREEK

072373301, Montgomery, IA

Built 1992 Load: 40.5 t ADT: 11

US 59

Fair

Over: WEST NISHNABOTNA RIVER

0.8 MI. S OF SR F-58, Shelby, IA

Built 1970 Load: 40.5 t ADT: 4,850

EB US 20

Fair

Over: ABANDON RR

0.1 mi. E of SR D25, Woodbury, IA

Built 1978 Load: 40.5 t ADT: 12,750

LOCAL

Fair

Over: KILSONS CREEK

090171502, Butler, IA

Built 1987 Load: 40.6 t ADT: 73

US 30

Fair

Over: MIDDLE RACCOON RIVER

1.4 mi. W of jct. U.S. 71, Carroll, IA

Built 1982 Load: 40.6 t ADT: 6,000

US 34 WB

Fair

Over: MITCHELL CREEK

3.6 mi. W of Jct. IA 1, Jefferson, IA

Built 2008 Load: 40.6 t ADT: 2,485

220TH AVE.

Fair

Over: WHITE OAK CREEK

083043402, Jones, IA

Built 1947 Load: 40.6 t ADT: 11

OMAHA RD

Fair

Over: WEST NODAWAY CREEK

075341303, Cass, IA

Built 2000 Load: 40.7 t ADT: 5

FM

Fair

Over: BLACKHAWK CREEK ,BRANCH

088163303, Grundy, IA

Built 1964 Load: 40.7 t ADT: 550

IA 22

Fair

Over: STREAM

0.6 mi. W of SR Y36, Muscatine, IA

Built 1984 Load: 40.7 t ADT: 1,560

US 218 SB

Fair

Over: CP RR

0.2 MI. N OF JCT. IA 92, Washington, IA

Built 1996 Load: 40.7 t ADT: 5,500

DUTCH LANE RD

Fair

Over: WHITE WATER CREEK

088E11702, Dubuque, IA

Built 2012 Load: 40.8 t ADT: 151

WB IA 2

Fair

Over: HORSE CREEK

1.0 mi. W of jct. I-29, Fremont, IA

Built 1987 Load: 40.8 t ADT: 4,000

S AVE

Fair

Over: STREAM

082291804, Greene, IA

Built 1953 Load: 40.8 t ADT: 26

FM

Fair

Over: BEAR CREEK

084E13304, Jackson, IA

Built 1995 Load: 40.8 t ADT: 240

490TH ST

Fair

Over: CREEK

100182401, Mitchell, IA

Built 1984 Load: 40.8 t ADT: 33

FIELD ENTR.

Fair

Over: SIDE DITCH

098072703, Winneshiek, IA

Built 1995 Load: 40.8 t ADT: 10

260TH AVE

Fair

Over: CLEAR CREEK

081E31404, Clinton, IA

Built 1995 Load: 40.9 t ADT: 570

US 169

Fair

Over: E FORK DES MOINES RIVER

1.3 mi. S of S Jct SR A42, Kossuth, IA

Built 1959 Load: 40.9 t ADT: 2,140

170TH ST

Fair

Over: DES MOINES RIVER

089291205, Webster, IA

Built 1979 Load: 40.9 t ADT: 3,132

FM

Fair

Over: BLUFF CREEK

084270801, Boone, IA

Built 1956 Load: 41.0 t ADT: 478

NB IA 14

Fair

Over: IOWA RIVER

0.8 MILE S OF JCT SR E27, Marshall, IA

Built 1968 Load: 41.0 t ADT: 2,950

FM

Fair

Over: DRY RUN

099391601, Osceola, IA

Built 1988 Load: 41.0 t ADT: 399

110TH STREET

Fair

Over: NISHNABOTNA RIVER

070391201, Page, IA

Built 1980 Load: 41.0 t ADT: 29

US 218 SB

Fair

Over: S. FORK LONG CREEK

1.5 MI. S OF JCT. IA 92, Washington, IA

Built 1997 Load: 41.0 t ADT: 5,650

SW RAMP

Fair

Over: LITTLE BEAR CREEK

0.1 MI. W OF Jct. SR V38, Iowa, IA

Built 1963 Load: 41.1 t ADT: 160

LOCAL

Fair

Over: CREEK

086E33203, Jackson, IA

Built 2002 Load: 41.1 t ADT: 20

I 880 EB

Fair

Over: OLD BOYER RIVER CHANNEL

0.5 MI. E OF E JCT. I-29, Pottawattamie, IA

Built 1966 Load: 41.1 t ADT: 670

LOCAL

Fair

Over: BUCK RUN

085342504, Carroll, IA

Built 1952 Load: 41.2 t ADT: 26

US 169

Fair

Over: N BRANCH NORTH RIVER

5.3 mi. S of Jct. SR F90, Madison, IA

Built 1983 Load: 41.2 t ADT: 4,280

SB US 61

Fair

Over: WAPSIPINICON BAYOU

1.8 MI. N OF SR F 33, Scott, IA

Built 1981 Load: 41.2 t ADT: 8,800

Showing 8,201-8,250 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.