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

Poor

Over: CREEK

089010204, Dubuque, IA

Built 1950 Load: 30.8 t ADT: 39

DYERSVILLE EAST RD

Poor

Over: CREEK

089022704, Dubuque, IA

Built 1964 Load: 30.8 t ADT: 511

FM

Poor

Over: SOLDIER CREEK

100331303, Emmet, IA

Built 1967 Load: 30.8 t ADT: 190

ABBEY RD.

Poor

Over: BEAVER CREEK

094072401, Fayette, IA

Built 1949 Load: 30.8 t ADT: 128

LOCAL

Poor

Over: LITTLE WOLF CREEK

086170201, Grundy, IA

Built 1976 Load: 30.8 t ADT: 33

FM

Poor

Over: BLACK HAWK CREEK

087152202, Grundy, IA

Built 1973 Load: 30.8 t ADT: 412

LOCAL

Poor

Over: MOSQUITO CREEK

087163302, Grundy, IA

Built 1983 Load: 30.8 t ADT: 33

LOCAL

Poor

Over: STREAM

080100502, Iowa, IA

Built 1976 Load: 30.8 t ADT: 20

RAMPART AVE

Poor

Over: SMALL STREAM

099161202, Mitchell, IA

Built 1974 Load: 30.8 t ADT: 59

FM

Poor

Over: BUCK CREEK

078161203, Poweshiek, IA

Built 1969 Load: 30.8 t ADT: 2,000

FM

Poor

Over: RACCOON RIVER

087361301, Sac, IA

Built 1974 Load: 30.8 t ADT: 110

SPRUCE

Poor

Over: DRAINAGE DITCH

100193104, Worth, IA

Built 1955 Load: 30.8 t ADT: 30

FM

Poor

Over: CREEK

088422402, Woodbury, IA

Built 1978 Load: 30.9 t ADT: 50

FM

Poor

Over: STREAM

070170103, Appanoose, IA

Built 1972 Load: 31.0 t ADT: 100

LOCAL RD

Poor

Over: BRANCH BLACKHAWK CREEK

088172601, Grundy, IA

Built 1956 Load: 31.0 t ADT: 15

LOCAL

Poor

Over: JORDAN CREEK

084152201, Tama, IA

Built 1940 Load: 31.0 t ADT: 39

N 15TH ST

Poor

Over: SOLDIER CREEK

089281700, Webster, IA

Built 1974 Load: 31.0 t ADT: 8,798

FM (LWC)

Poor

Over: SMALL STREAM

085120502, Benton, IA

Built 1980 Load: 31.1 t ADT: 20

LOCAL

Poor

Over: MONTGOMERY CREEK

085253102, Boone, IA

Built 1915 Load: 31.1 t ADT: 5

LOCAL ROAD

Poor

Over: SOLDIER RIVER

086392802, Ida, IA

Built 1900 Load: 31.1 t ADT: 11

FA-GASTON AVE

Poor

Over: KEG CREEK

072420603, Mills, IA

Built 1967 Load: 31.1 t ADT: 1,065

LOCAL

Poor

Over: CRANE CREEK

095110401, Chickasaw, IA

Built 1980 Load: 31.2 t ADT: 41

LOCAL

Poor

Over: STREAM

068171604, Appanoose, IA

Built 1900 Load: 31.3 t ADT: 51

LOCAL

Poor

Over: BR WILDCAT CK

084102702, Benton, IA

Built 1957 Load: 31.3 t ADT: 15

310TH STREET

Poor

Over: MID TARKIO CREEK

067392701, Page, IA

Built 1968 Load: 31.3 t ADT: 329

FM

Poor

Over: BLACK HAWK CREEK

087152002, Grundy, IA

Built 1979 Load: 31.4 t ADT: 687

FM 150TH ST

Poor

Over: LITTLE WAPSIPINICON

098142301, Howard, IA

Built 1967 Load: 31.4 t ADT: 452

FM ADDISON AVE

Poor

Over: WAPSIPINICON RIVER

099140702, Howard, IA

Built 1968 Load: 31.4 t ADT: 285

FM

Poor

Over: SMALL STREAM

087E41405, Jackson, IA

Built 1986 Load: 31.4 t ADT: 40

FM

Poor

Over: WHITE BREAST CREEK

073222205, Lucas, IA

Built 1957 Load: 31.4 t ADT: 440

310TH ST

Poor

Over: STREAM

071413202, Mills, IA

Built 1960 Load: 31.4 t ADT: 325

FM

Poor

Over: SS #98

094331101, Palo Alto, IA

Built 1973 Load: 31.4 t ADT: 120

FM

Poor

Over: D D #66 BR SO LIZARD CK

090331201, Pocahontas, IA

Built 1970 Load: 31.4 t ADT: 71

FM

Poor

Over: BRANCH SALT CREEK

084130603, Tama, IA

Built 1996 Load: 31.4 t ADT: 344

P13 VALLEY AVE

Poor

Over: DD #83

087311702, Calhoun, IA

Built 1917 Load: 31.5 t ADT: 60

FM 255TH ST

Poor

Over: BEAVERDAM CREEK

093200103, Franklin, IA

Built 1969 Load: 31.5 t ADT: 687

S14/620TH AVE

Poor

Over: CALAMUS CREEK

082221802, Story, IA

Built 1941 Load: 31.5 t ADT: 988

FM

Poor

Over: PRAIRIE CREEK

082110801, Benton, IA

Built 1959 Load: 31.6 t ADT: 45

FM

Poor

Over: IOWA RIVER

082132002, Tama, IA

Built 1968 Load: 31.6 t ADT: 786

LOCAL

Poor

Over: WEASEL CK

082100701, Benton, IA

Built 1957 Load: 31.7 t ADT: 28

LOCAL

Poor

Over: LITTLE TURKEY

096111101, Chickasaw, IA

Built 1969 Load: 31.7 t ADT: 47

200 TH

Poor

Over: CREEK

084323001, Greene, IA

Built 1956 Load: 31.7 t ADT: 35

FAS 3556

Poor

Over: CREEK

086230602, Hamilton, IA

Built 1947 Load: 31.7 t ADT: 478

125TH ST

Poor

Over: BR CRANE CREEK

098130303, Howard, IA

Built 1955 Load: 31.7 t ADT: 10

FM

Poor

Over: SM STREAM

075093109, Washington, IA

Built 1928 Load: 31.7 t ADT: 10

FM 130TH AVE

Poor

Over: OCHEYEDAN RIVER

096381002, Clay, IA

Built 1971 Load: 31.8 t ADT: 1,287

FM

Poor

Over: ROCK CREEK

076121802, Keokuk, IA

Built 1956 Load: 31.8 t ADT: 35

FM

Poor

Over: BRANCH BURNETTE CREEK

084170603, Marshall, IA

Built 1984 Load: 31.8 t ADT: 304

240TH AVE

Poor

Over: CREEK

080E41306, Scott, IA

Built 1962 Load: 31.8 t ADT: 870

LOCAL

Poor

Over: SMALL STREAM

094132401, Chickasaw, IA

Built 1982 Load: 31.9 t ADT: 11

Showing 19,001-19,050 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.