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

290TH ST

Fair

Over: S.BR.CROOKED CREEK

087280805, Webster, IA

Built 1950 Load: 15.9 t ADT: 1,147

FM

Fair

Over: VILLAGE CREEK

098040903, Allamakee, IA

Built 1968 Load: 16.0 t ADT: 25

LOCAL

Fair

Over: STREAM

067171904, Appanoose, IA

Built 1977 Load: 16.0 t ADT: 21

COUNTY RD

Fair

Over: CROOKED CREEK

FM 078342402, Audubon, IA

Built 1955 Load: 16.0 t ADT: 15

IVANHOE ST

Fair

Over: RIVER

091130904, Bremer, IA

Built 1961 Load: 16.0 t ADT: 59

340TH

Fair

Over: ROCK FALLS CREEK

097319003, Cerro Gordo, IA

Built 1924 Load: 16.0 t ADT: 39

LOCAL

Fair

Over: TURKEY RUN

068240302, Decatur, IA

Built 1951 Load: 16.0 t ADT: 5

FM

Fair

Over: HOG CREEK

068242506, Decatur, IA

Built 1955 Load: 16.0 t ADT: 20

LOCAL

Fair

Over: S ELK CREEK

068270903, Decatur, IA

Built 2002 Load: 16.0 t ADT: 11

FM

Fair

Over: ELK CREEK

069270503, Decatur, IA

Built 1950 Load: 16.0 t ADT: 26

FM

Fair

Over: BIG HOLLOW CREEK

071042503, Des Moines, IA

Built 1955 Load: 16.0 t ADT: 100

600 140TH ST

Fair

Over: DD #8

094251801, Hancock, IA

Built 1955 Load: 16.0 t ADT: 15

LOCAL

Fair

Over: TIPTON CREEK

088223302, Hardin, IA

Built 1900 Load: 16.0 t ADT: 25

FM

Fair

Over: PRICE CREEK

081100203, Iowa, IA

Built 1956 Load: 16.0 t ADT: 60

S 68TH AVE E

Fair

Over: N SKUNK RIVER

079173401, Jasper, IA

Built 1955 Load: 16.0 t ADT: 25

FM

Fair

Over: CHARITON RIVER

071211504, Lucas, IA

Built 1970 Load: 16.0 t ADT: 25

LOCAL RD

Fair

Over: JONES CREEK

075262104, Madison, IA

Built 1975 Load: 16.0 t ADT: 5

LCL-OMAN AVE

Fair

Over: DEER CREEK

071401701, Mills, IA

Built 1962 Load: 16.0 t ADT: 26

LOCAL

Fair

Over: STREAM

099391602, Osceola, IA

Built 1940 Load: 16.0 t ADT: 30

LOCAL

Fair

Over: OCHEYEDAN RIVER

099400902, Osceola, IA

Built 1939 Load: 16.0 t ADT: 72

LOCAL

Fair

Over: OTTER CREEK

100422502, Osceola, IA

Built 1940 Load: 16.0 t ADT: 21

LOCAL

Fair

Over: OTTER CREEK

100422602, Osceola, IA

Built 1938 Load: 16.0 t ADT: 50

230TH STREET

Fair

Over: TARKIO RIVER

068381601, Page, IA

Built 1948 Load: 16.0 t ADT: 34

LOCAL

Fair

Over: PILOT CREEK

092310104, Pocahontas, IA

Built 1954 Load: 16.0 t ADT: 71

LOCAL

Fair

Over: SOUTH BRANCH SALT CREEK

084133002, Tama, IA

Built 1940 Load: 16.0 t ADT: 49

LOCAL

Fair

Over: CAMP CREEK

077083601, Washington, IA

Built 1954 Load: 16.0 t ADT: 161

250TH STREET

Fair

Over: W BRANCH 102 RIVER

071332001, Adams, IA

Built 1957 Load: 16.1 t ADT: 50

110TH STREET

Fair

Over: THOMPSON CREEK

073330701, Adams, IA

Built 1955 Load: 16.1 t ADT: 15

LOCAL

Fair

Over: BR RACCOON RIVER

093363404, Buena Vista, IA

Built 1976 Load: 16.1 t ADT: 45

FM

Fair

Over: PURGATORY

086333601, Calhoun, IA

Built 1938 Load: 16.1 t ADT: 34

LOCAL

Fair

Over: FIELD STREAM

082332302, Carroll, IA

Built 1972 Load: 16.1 t ADT: 50

FM

Fair

Over: WEST NISHNABOTNA RIVER

083363501, Carroll, IA

Built 1991 Load: 16.1 t ADT: 45

LOCAL

Fair

Over: FIELD STREAM

085351502, Carroll, IA

Built 1993 Load: 16.1 t ADT: 45

LOCAL K AVE

Fair

Over: BEAR CREEK

093412302, Cherokee, IA

Built 1927 Load: 16.1 t ADT: 30

LOCAL

Fair

Over: SMALL STREAM

082380602, Crawford, IA

Built 2001 Load: 16.1 t ADT: 21

FM

Fair

Over: MIDDLE RACOON

080310913, Guthrie, IA

Built 1958 Load: 16.1 t ADT: 100

FM

Fair

Over: BRUSH CREEK

070050603, Henry, IA

Built 1956 Load: 16.1 t ADT: 50

LOCAL

Fair

Over: INDIAN CREEK

073222902, Lucas, IA

Built 1954 Load: 16.1 t ADT: 47

LOCAL

Fair

Over: STREAM

077273302, Madison, IA

Built 1981 Load: 16.1 t ADT: 60

FM

Fair

Over: ENGLISH CREEK

074200403, Marion, IA

Built 1954 Load: 16.1 t ADT: 230

US 69

Fair

Over: FOURMILE CREEK

1.3 miles N of IA 160, Polk, IA

Built 1949 Load: 16.1 t ADT: 6,800

MAGNOLIA ROAD

Fair

Over: STREAM

076392201, Pottawattamie, IA

Built 1985 Load: 16.1 t ADT: 5

FM

Fair

Over: W FORK GRAND RIVER

069301901, Ringgold, IA

Built 1966 Load: 16.1 t ADT: 34

FM

Fair

Over: SMALL

067322843, Taylor, IA

Built 1963 Load: 16.1 t ADT: 61

FM

Fair

Over: BRUSH CREEK

071143306, Wapello, IA

Built 1955 Load: 16.1 t ADT: 150

FM

Fair

Over: COMPETINE CREEK

073121507, Wapello, IA

Built 1962 Load: 16.1 t ADT: 130

LOCAL 335TH ST.

Fair

Over: SMALL STREAM

087083603, Buchanan, IA

Built 1998 Load: 16.2 t ADT: 78

FM 145TH ST

Fair

Over: LITTLE WAPSIPINICON

090102805, Buchanan, IA

Built 1965 Load: 16.2 t ADT: 137

FM

Fair

Over: NORTH RACOON RIVER

085330801, Carroll, IA

Built 1940 Load: 16.2 t ADT: 71

280TH ST

Fair

Over: PANTHER CREEK

079282703, Dallas, IA

Built 1968 Load: 16.2 t ADT: 500

Showing 1,601-1,650 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.