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

IA 141

Fair

Over: DRAINAGE DITCH

0.4 MI. E OF JCT. US 169, Dallas, IA

Built 1978 Load: 28.2 t ADT: 9,400

100 TH

Fair

Over: CEDAR CREEK

085320301, Greene, IA

Built 1979 Load: 28.2 t ADT: 20

LOCAL

Fair

Over: CREEK

089393302, Ida, IA

Built 1968 Load: 28.2 t ADT: 35

BELLEVUECASCADE RD

Fair

Over: LOST CREEK

086E10706, Jackson, IA

Built 1983 Load: 28.2 t ADT: 590

FM IWV RD

Fair

Over: N BRANCH OLD MANS CR

079081503, Johnson, IA

Built 2004 Load: 28.2 t ADT: 480

50TH AVE.

Fair

Over: SMALL CREEK

083010902, Jones, IA

Built 1983 Load: 28.2 t ADT: 10

215TH AVE

Fair

Over: DUTCH CREEK

084042204, Jones, IA

Built 1991 Load: 28.2 t ADT: 108

148TH ST.

Fair

Over: MINERAL CREEK

085022605, Jones, IA

Built 1988 Load: 28.2 t ADT: 69

COUNTY RD D-62

Fair

Over: SILVER CREEK

086041006, Jones, IA

Built 1960 Load: 28.2 t ADT: 599

ANDERSON RD

Fair

Over: BUFFALO CREEK

085052403, Linn, IA

Built 1981 Load: 28.2 t ADT: 88

LOCAL ROAD

Fair

Over: ALBERTSON CREEK

098472601, Lyon, IA

Built 1900 Load: 28.2 t ADT: 21

LOCAL

Fair

Over: CREEK

084191301, Marshall, IA

Built 1920 Load: 28.2 t ADT: 21

PRIMROSE AVE

Fair

Over: BURR OAK CREEK

098161006, Mitchell, IA

Built 1960 Load: 28.2 t ADT: 501

US 71

Fair

Over: MIDDLE NODAWAY RIVER

2.2 MI. S OF SR H-46, Montgomery, IA

Built 1972 Load: 28.2 t ADT: 2,090

FM

Fair

Over: NO FOLK FLOYD RIVER

097410901, O'Brien, IA

Built 1994 Load: 28.2 t ADT: 71

FM

Fair

Over: KEG CREEK

079390802, Shelby, IA

Built 1973 Load: 28.2 t ADT: 450

LOCAL

Fair

Over: FLOYD RIVER

096433401, Sioux, IA

Built 1983 Load: 28.2 t ADT: 26

LOCAL

Fair

Over: SMALL STREAM

071310302, Union, IA

Built 1995 Load: 28.2 t ADT: 35

LOCAL

Fair

Over: WEST FORK OF CEDAR RIVER

092180704, Butler, IA

Built 1952 Load: 28.3 t ADT: 51

LOCAL

Fair

Over: SO WHITE BREAST CREEK

071252204, Clarke, IA

Built 1983 Load: 28.3 t ADT: 71

FM

Fair

Over: COTTONWOOD DRAIN

071013102, Des Moines, IA

Built 1953 Load: 28.3 t ADT: 60

IA 23

Fair

Over: STREAM

0.4 mi. N of Jct. IA 149, Keokuk, IA

Built 1976 Load: 28.3 t ADT: 1,980

7TH AVE

Fair

Over: INDIAN CREEK

083070100, Linn, IA

Built 1994 Load: 28.3 t ADT: 20,679

PK 693 410TH ST

Fair

Over: LOST BRANCH CREEK

6 mi.S, .1 E of 34/280 Av, Lucas, IA

Built 1900 Load: 28.3 t ADT: 21

LOCAL

Fair

Over: CEDAR CREEK

074142904, Mahaska, IA

Built 1900 Load: 28.3 t ADT: 20

LOCAL

Fair

Over: WINN BRANCH CREEK

074212903, Marion, IA

Built 1976 Load: 28.3 t ADT: 11

I-235 & 17TH ST

Fair

Over: BLUE CREEK

1.1 MILES W OF JCT IA 28, Polk, IA

Built 1968 Load: 28.3 t ADT: 113,200

ASPEN ROAD

Fair

Over: MUD CREEK

074413601, Pottawattamie, IA

Built 2009 Load: 28.3 t ADT: 26

LOCAL

Fair

Over: NORTH WALNUT CREEK

082143502, Tama, IA

Built 1966 Load: 28.3 t ADT: 26

US 169

Fair

Over: DEER CREEK

0.8 mi. N of SR C66, Webster, IA

Built 1958 Load: 28.3 t ADT: 4,680

LOCAL

Fair

Over: NORTH FORK YELLOW RIVER

096071303, Winneshiek, IA

Built 1913 Load: 28.3 t ADT: 29

E BIG ROCK RD

Fair

Over: TRIB TO WAPSIPINICON RVR

89-11-03-01-10, Black Hawk, IA

Built 1920 Load: 28.4 t ADT: 49

IA 188

Fair

Over: DRY RUN CREEK

3.4 mi. W of Jct. US 218, Butler, IA

Built 1959 Load: 28.4 t ADT: 490

IOWA 122

Fair

Over: IDEAL CREEK

1.2 Mi. W of Sec. Rd. S56, Cerro Gordo, IA

Built 1952 Load: 28.4 t ADT: 4,930

US 18

Fair

Over: UNNAMED CREEK

0.1 mi. E of jct. SR B45, Clayton, IA

Built 1988 Load: 28.4 t ADT: 4,730

FM

Fair

Over: BROWN CREEK

100331601, Emmet, IA

Built 1967 Load: 28.4 t ADT: 170

215 TH

Fair

Over: RACCOON RIVER

084313106, Greene, IA

Built 1949 Load: 28.4 t ADT: 46

FM

Fair

Over: DOWD CREEK, BRANCH

086182001, Grundy, IA

Built 1965 Load: 28.4 t ADT: 187

LOCAL

Fair

Over: HONEY CREEK

087222402, Hardin, IA

Built 1985 Load: 28.4 t ADT: 51

UP-BOULDER RD

Fair

Over: TRIB TO SILVER CREEK

086051301, Linn, IA

Built 1986 Load: 28.4 t ADT: 20

NB US 65

Fair

Over: SKUNK RIVER

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

Built 1972 Load: 28.4 t ADT: 4,800

HAWK DR

Fair

Over: DRAINAGE DITCH-SIDE

IN DOUDS - LT. SIDE DITCH, Van Buren, IA

Built 1991 Load: 28.4 t ADT: 10

FM

Fair

Over: YELLOW RIVER

096050506, Allamakee, IA

Built 1968 Load: 28.5 t ADT: 589

LOCAL

Fair

Over: CREEK

079360201, Audubon, IA

Built 1931 Load: 28.5 t ADT: 21

LOCAL- N AVE

Fair

Over: BRANCH LITTLE SIOUX

090402002, Cherokee, IA

Built 1937 Load: 28.5 t ADT: 26

LOCAL

Fair

Over: CREEK

095111901, Chickasaw, IA

Built 1970 Load: 28.5 t ADT: 62

FM

Fair

Over: W FK W NISHNABOTNA RIVER

082381202, Crawford, IA

Built 1963 Load: 28.5 t ADT: 816

LOCAL

Fair

Over: BEAVER CREEK

081263302, Dallas, IA

Built 1985 Load: 28.5 t ADT: 26

IA 3

Fair

Over: STREAM

3.3 MI. E OF Jct. IA 150, Fayette, IA

Built 1988 Load: 28.5 t ADT: 2,770

IA 3

Fair

Over: SO FORK MAQUOKETA RIVER

4.8 MI. W OF JCT. IA 187, Fayette, IA

Built 1925 Load: 28.5 t ADT: 1,400

Showing 5,051-5,100 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.