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: LONG CREEK

070042204, Des Moines, IA

Built 1966 Load: 20.8 t ADT: 690

FM

Poor

Over: DRAINAGE DITCH

087241704, Hamilton, IA

Built 1920 Load: 20.8 t ADT: 34

FM

Poor

Over: DRAINAGE DITCH

088232404, Hamilton, IA

Built 1923 Load: 20.8 t ADT: 11

LOCAL

Poor

Over: STREAM

073043102, Louisa, IA

Built 1920 Load: 20.8 t ADT: 21

LOCAL

Poor

Over: DRAINAGE

074271604, Madison, IA

Built 1945 Load: 20.8 t ADT: 29

LOCAL

Poor

Over: SMALL

068320602, Taylor, IA

Built 1980 Load: 20.8 t ADT: 15

LOCAL

Poor

Over: FOUR MILE CREEK

072280103, Union, IA

Built 1967 Load: 20.8 t ADT: 5

FM

Poor

Over: CREEK

092230202, Wright, IA

Built 1977 Load: 20.8 t ADT: 20

LOCAL

Poor

Over: UNNAMED STREAM

068193002, Appanoose, IA

Built 1976 Load: 20.9 t ADT: 11

LOCAL

Poor

Over: BR BUCKEYE CK

082122207, Benton, IA

Built 1976 Load: 20.9 t ADT: 45

LOCAL

Poor

Over: HORTON CREEK

094143601, Chickasaw, IA

Built 1978 Load: 20.9 t ADT: 30

FM

Poor

Over: SMALL

096123003, Chickasaw, IA

Built 1978 Load: 20.9 t ADT: 25

300TH ST

Poor

Over: BRANCH NAGEL CREEK

092060913, Clayton, IA

Built 1935 Load: 20.9 t ADT: 11

FM

Poor

Over: IOWA RIVER

091221902, Franklin, IA

Built 1959 Load: 20.9 t ADT: 320

INDIGO AVE

Poor

Over: OTTER CREEK

093211602, Franklin, IA

Built 1971 Load: 20.9 t ADT: 29

FM

Poor

Over: SOUTH FORK IOWA RIVER

088211902, Hardin, IA

Built 1900 Load: 20.9 t ADT: 44

LOCAL

Poor

Over: CREEK

089221604, Hardin, IA

Built 1978 Load: 20.9 t ADT: 91

FM EASTON TRAIL

Poor

Over: ALLEN CREEK

081433403, Harrison, IA

Built 1969 Load: 20.9 t ADT: 335

POWESHIEK IOWA RD

Poor

Over: HONEY CREEK

081123102, Iowa, IA

Built 1969 Load: 20.9 t ADT: 20

W 93RD ST S

Poor

Over: PRAIRIE CREEK

078203002, Jasper, IA

Built 1934 Load: 20.9 t ADT: 20

NEWPORT RD.

Poor

Over: SMALL CREEK

084033402, Jones, IA

Built 1945 Load: 20.9 t ADT: 62

LOCAL

Poor

Over: BR OF CHARITON RIVER

071202801, Lucas, IA

Built 1968 Load: 20.9 t ADT: 26

FM

Poor

Over: DRAINAGE

074293201, Madison, IA

Built 1941 Load: 20.9 t ADT: 20

FM

Poor

Over: PINE CREEK

078E13002, Muscatine, IA

Built 1955 Load: 20.9 t ADT: 1,600

200TH ST

Poor

Over: MINK CREEK

092462701, Plymouth, IA

Built 1949 Load: 20.9 t ADT: 34

JUNIPER AVE

Poor

Over: MINK CREEK

093460202, Plymouth, IA

Built 1948 Load: 20.9 t ADT: 34

YELLOW BANKS PK

Poor

Over: STREAM

078232301, Polk, IA

Built 1980 Load: 20.9 t

FM

Poor

Over: NORTH WALNUT CREEK

082143302, Tama, IA

Built 1970 Load: 20.9 t ADT: 20

LOCAL

Poor

Over: TWELVE MILE CREEK

086150902, Tama, IA

Built 1970 Load: 20.9 t ADT: 26

LOCAL

Poor

Over: BR.SOUTH RIVER

076221009, Warren, IA

Built 1940 Load: 20.9 t ADT: 11

LOCAL

Poor

Over: STREAM

089433001, Woodbury, IA

Built 1997 Load: 20.9 t ADT: 11

150TH STREET

Poor

Over: KEMP CREEK

073333201, Adams, IA

Built 1961 Load: 21.0 t ADT: 180

CORNING-CARL RD

Poor

Over: KEMP CREEK

073333202, Adams, IA

Built 1961 Load: 21.0 t ADT: 199

LOCAL RD

Poor

Over: TEEPLE CREEK

097061401, Allamakee, IA

Built 1900 Load: 21.0 t ADT: 60

LOCAL

Poor

Over: STREAM

068193002, Appanoose, IA

Built 1900 Load: 21.0 t ADT: 11

LOCAL

Poor

Over: SMALL STREAM

072020604, Des Moines, IA

Built 1985 Load: 21.0 t ADT: 11

K AVE

Poor

Over: HARDIN CREEK

085312302, Greene, IA

Built 1959 Load: 21.0 t ADT: 21

LOCAL

Poor

Over: STREAM

079110202, Iowa, IA

Built 1976 Load: 21.0 t ADT: 20

FM

Poor

Over: SMALL STREAM

079112702, Iowa, IA

Built 1930 Load: 21.0 t ADT: 60

LOCAL

Poor

Over: SMALL STREAM

080192005, Jasper, IA

Built 1930 Load: 21.0 t ADT: 41

LOCAL

Poor

Over: BRUSH CREEK

082170503, Marshall, IA

Built 1964 Load: 21.0 t ADT: 30

FM

Poor

Over: NISHNABOTNA TRIB

071383103, Montgomery, IA

Built 1957 Load: 21.0 t ADT: 173

310TH STREET

Poor

Over: STREAM

075413202, Pottawattamie, IA

Built 1994 Load: 21.0 t ADT: 60

LOCAL

Poor

Over: SO ENGLISH RIVER

078142702, Poweshiek, IA

Built 1980 Load: 21.0 t ADT: 40

560TH AVE

Poor

Over: HAMILTON-STORY 1 OPEN DD

085233102, Story, IA

Built 1900 Load: 21.0 t ADT: 34

FM

Poor

Over: NORTH WALNUT CREEK

082153602, Tama, IA

Built 1930 Load: 21.0 t ADT: 15

LOCAL

Poor

Over: SMALL

084160202, Tama, IA

Built 1983 Load: 21.0 t ADT: 49

FM

Poor

Over: EAST 102 RIVER

067340905, Taylor, IA

Built 1965 Load: 21.0 t ADT: 71

FM

Poor

Over: ROCK CREEK

069092103, Van Buren, IA

Built 1953 Load: 21.0 t ADT: 70

LOCAL ROAD

Poor

Over: SMALL STREAM

075070102, Washington, IA

Built 1917 Load: 21.0 t ADT: 11

Showing 18,101-18,150 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.