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

SB US 61

Fair

Over: SILVER CREEK

0.9 mi. N of N Jct. US 30, Clinton, IA

Built 1974 Load: 44.0 t ADT: 6,350

FM

Fair

Over: MUD CREEK

085191903, Marshall, IA

Built 1967 Load: 44.0 t ADT: 265

FM

Fair

Over: RACCOON RIVER

086351410, Sac, IA

Built 1985 Load: 44.0 t ADT: 159

FM

Fair

Over: ALDRICH CREEK

087412001, Ida, IA

Built 1970 Load: 44.1 t ADT: 210

LOCAL

Fair

Over: TETE DES MORTS RIVER

087E40805, Jackson, IA

Built 1979 Load: 44.1 t ADT: 34

FM

Fair

Over: PERRY CREEK

091471402, Plymouth, IA

Built 1949 Load: 44.1 t ADT: 1,028

WB US 275&IA 92

Fair

Over: BNSF RR AND DL #5

0.4 MI. N of N Jct. I-29, Pottawattamie, IA

Built 2007 Load: 44.1 t ADT: 5,050

LOCAL

Fair

Over: CREEK

088400202, Ida, IA

Built 1999 Load: 44.2 t ADT: 21

FM

Fair

Over: STONY FORK

073221704, Lucas, IA

Built 1947 Load: 44.3 t ADT: 50

BIRDLAND DRIVE

Fair

Over: BIRDLAND LAGOON

079243583, Polk, IA

Built 1930 Load: 44.3 t ADT: 351

184TH LANE

Fair

Over: STEER CREEK

080441505, Harrison, IA

Built 1969 Load: 44.4 t ADT: 10

LOCAL

Fair

Over: PLEASANT CREEK

085E41104, Jackson, IA

Built 1998 Load: 44.4 t ADT: 11

FM

Fair

Over: BRUSH CREEK

072091505, Jefferson, IA

Built 1988 Load: 44.4 t ADT: 200

US 34

Fair

Over: INDIAN CREEK

0.1 MI. W OF W JCT SR M16, Mills, IA

Built 1989 Load: 44.4 t ADT: 4,260

FM

Fair

Over: DD #114

096332601, Palo Alto, IA

Built 1973 Load: 44.4 t ADT: 275

IA 148

Fair

Over: MIDDLE BR W 102 RIVER

2.0 MI.S.OF SR J-20, Taylor, IA

Built 1961 Load: 44.4 t ADT: 890

IA 281

Fair

Over: WAPSIPINICON RIVER

2.2 MI. E OF S.R. C57, Black Hawk, IA

Built 1989 Load: 44.5 t ADT: 1,240

MARTELLE RD

Fair

Over: ELBOW CREEK

083051201, Linn, IA

Built 1977 Load: 44.6 t ADT: 363

WILLOW AVENUE

Fair

Over: STREAM

069362604, Page, IA

Built 1954 Load: 44.6 t ADT: 71

LOCAL

Fair

Over: STREAM

068310103, Ringgold, IA

Built 1930 Load: 44.6 t ADT: 29

UTAH AVE

Fair

Over: BLACKHAWK CREEK

000000000, Scott, IA

Built 1960 Load: 44.6 t ADT: 851

FM

Fair

Over: ELKHORN CREEK

078360503, Audubon, IA

Built 1971 Load: 44.7 t ADT: 597

MANSON RD

Fair

Over: CATFISH CREEK

N.E. OF CREEKWOOD DR, Dubuque, IA

Built 2002 Load: 44.7 t ADT: 340

LOCAL

Fair

Over: SMALL CREEK

085E11804, Jackson, IA

Built 2007 Load: 44.7 t ADT: 128

IA 149

Fair

Over: STREAM

0.6 MI. N of Iowa 23, Keokuk, IA

Built 1976 Load: 44.7 t ADT: 1,450

FM

Fair

Over: QUARTER SECTION RUN CK

091133402, Bremer, IA

Built 2001 Load: 44.8 t ADT: 2,023

LOCAL

Fair

Over: DRY RUN

085E61804, Jackson, IA

Built 2001 Load: 44.8 t ADT: 26

WB IA 163

Fair

Over: MUD CREEK

2.3 MILES W OF JCT IA 316, Polk, IA

Built 1963 Load: 44.8 t ADT: 7,450

NB I-380

Fair

Over: SPRING CREEK

1.6 Mi. N OF Jct. SR V65, Black Hawk, IA

Built 1984 Load: 44.9 t ADT: 8,550

SB I-380

Fair

Over: SPRING CREEK

1.6 Mi. N OF Jct. SR V65, Black Hawk, IA

Built 1984 Load: 44.9 t ADT: 8,550

WB US 20

Fair

Over: BUFFALO CREEK

2.3 MI. E OF JCT. SR W40, Buchanan, IA

Built 1978 Load: 44.9 t ADT: 3,500

ZINNIA

Fair

Over: ROCK CREEK

095191305, Cerro Gordo, IA

Built 1961 Load: 44.9 t ADT: 265

IA 136

Fair

Over: MILL CREEK

2.7 Mi. N of N Jct. US 67, Clinton, IA

Built 1989 Load: 45.0 t ADT: 1,430

US 18 WB IA 27 NB

Fair

Over: UP RR

1.5 mi. W of US 65, Cerro Gordo, IA

Built 1997 Load: 45.1 t ADT: 4,450

LOCAL

Fair

Over: WHITE BREAST CR

072262606, Clarke, IA

Built 1989 Load: 45.1 t ADT: 100

US 30

Fair

Over: SIX MILE CREEK

0.3 mi. E of IA 44, Harrison, IA

Built 1988 Load: 45.1 t ADT: 4,490

G-71

Fair

Over: CEDAR CREEK

074181401, Marion, IA

Built 1990 Load: 45.1 t ADT: 920

IA 16

Fair

Over: BNSF RR

0.4 mi. S of Jct. U.S. 34, Wapello, IA

Built 1984 Load: 45.2 t ADT: 2,440

FM

Fair

Over: RACCOON RIVER

086342506, Calhoun, IA

Built 1985 Load: 45.3 t ADT: 90

W AVENUE

Fair

Over: SMALL STREAM

082412801, Crawford, IA

Built 1958 Load: 45.3 t ADT: 26

LOCAL

Fair

Over: SMALL CREEK

084E73103, Jackson, IA

Built 1998 Load: 45.3 t ADT: 79

FM

Fair

Over: CEDAR CREEK

076282602, Madison, IA

Built 1989 Load: 45.3 t ADT: 100

MILLER CREEK RD

Fair

Over: TRIB TO MILLER CREEK

87-12-04-01-10, Black Hawk, IA

Built 1986 Load: 45.4 t ADT: 49

DYSART RD

Fair

Over: TRIB TO MILLER CREEK

87-12-07-02-10, Black Hawk, IA

Built 1994 Load: 45.4 t ADT: 1,660

W EAGLE RD

Fair

Over: ROCK CREEK

87-14-24-01-10, Black Hawk, IA

Built 2005 Load: 45.4 t ADT: 471

UNION AVE

Fair

Over: EAST SUGAR CREEK

080011604, Cedar, IA

Built 2000 Load: 45.4 t ADT: 970

FM 200 AVE

Fair

Over: HONEY CREEK

090052602, Delaware, IA

Built 1998 Load: 45.4 t ADT: 570

FM

Fair

Over: JOHNS CREEK

087011604, Dubuque, IA

Built 1991 Load: 45.4 t ADT: 590

LOCAL

Fair

Over: DRY RUN

097172003, Floyd, IA

Built 1981 Load: 45.4 t ADT: 49

S 60TH AVE W

Fair

Over: SEWER CREEK

079192801, Jasper, IA

Built 1989 Load: 45.4 t ADT: 800

Showing 8,401-8,450 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.