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

LOCAL ROAD

Structurally Deficient

Over: BEAVER CREEK

089172801, Grundy, IA

Built 1948 ADT: 11

LOCAL ROAD

Structurally Deficient

Over: MIDDLE FORK BEAVER CREEK

089181801, Grundy, IA

Built 1952 ADT: 99

LOCAL

Structurally Deficient

Over: BEAVER CREEK

078300604, Guthrie, IA

Built 1959 ADT: 71

LOCAL

Structurally Deficient

Over: SOUTH BEAVER CREEK

078310510, Guthrie, IA

Built 1945 ADT: 11

LOCAL

Structurally Deficient

Over: STREAM

078332103, Guthrie, IA

Built 1940 ADT: 20

LOCAL

Structurally Deficient

Over: SMALL CREEK

078333202, Guthrie, IA

Built 1949 ADT: 11

LOCAL

Structurally Deficient

Over: MASON CREEK

079322403, Guthrie, IA

Built 1940 ADT: 11

LOCAL

Structurally Deficient

Over: MASON CREEK

079322808, Guthrie, IA

Built 1920 ADT: 11

FM

Structurally Deficient

Over: LONE GROVE CREEK

079330202, Guthrie, IA

Built 1950 ADT: 71

LOCAL

Structurally Deficient

Over: SEELY CREEK

079331303, Guthrie, IA

Built 1957 ADT: 40

LOCAL

Structurally Deficient

Over: STREAM

080303406, Guthrie, IA

Built 1940 ADT: 5

LOCAL

Structurally Deficient

Over: BRUSHY CK

080312904, Guthrie, IA

Built 1910 ADT: 60

LOCAL

Structurally Deficient

Over: STREAM

080320504, Guthrie, IA

Built 1960 ADT: 11

LOCAL

Structurally Deficient

Over: STREAM

081310902, Guthrie, IA

Built 1953 ADT: 29

FM

Structurally Deficient

Over: SMALL CREEK

081311901, Guthrie, IA

Built 1955 ADT: 26

INKPADUTA AVE

Structurally Deficient

Over: BOONE RIVER

088253003, Hamilton, IA

Built 1907 ADT: 40

280TH ST

Structurally Deficient

Over: BOONE RIVER

088253108, Hamilton, IA

Built 1902 ADT: 62

1940 DEER AVE

Structurally Deficient

Over: BOONE RIVER

095261502, Hancock, IA

Built 1967 ADT: 26

FM 330 190TH ST

Structurally Deficient

Over: BOONE RIVER

095262103, Hancock, IA

Built 1925 ADT: 20

3350 CRANE AVE

Structurally Deficient

Over: BUFFALO CREEK

097260402, Hancock, IA

Built 1963 ADT: 26

LOCAL

Structurally Deficient

Over: STREAM

086190102, Hardin, IA

Built 1981 ADT: 16

LOCAL

Structurally Deficient

Over: HONEY CREEK

086193103, Hardin, IA

Built 1919 ADT: 16

LOCAL

Structurally Deficient

Over: HONEY CREEK

086200703, Hardin, IA

Built 1953 ADT: 21

LOCAL

Structurally Deficient

Over: MINERVA CREEK

086221302, Hardin, IA

Built 1984 ADT: 30

LOCAL

Structurally Deficient

Over: BEAVER CREEK

087202401, Hardin, IA

Built 1958 ADT: 15

FM

Structurally Deficient

Over: SOUTH FORK IOWA RIVER

088211802, Hardin, IA

Built 1954 ADT: 44

LOCAL

Structurally Deficient

Over: SOUTH FORK IOWA RIVER

088220402, Hardin, IA

Built 1982 ADT: 51

FM

Structurally Deficient

Over: DD

088220502, Hardin, IA

Built 1963 ADT: 25

LOCAL

Structurally Deficient

Over: IA RIVER

088221204, Hardin, IA

Built 1965 ADT: 11

8TH STREET

Structurally Deficient

Over: BOYER RIVER

000000000, Harrison, IA

Built 1900 ADT: 123

NEELY TRAIL

Structurally Deficient

Over: WILLOW CREEK

080432707, Harrison, IA

Built 1940 ADT: 45

LOCAL

Structurally Deficient

Over: LYNN CREEK

072061801, Henry, IA

Built 1992 ADT: 51

LOCAL

Structurally Deficient

Over: SMALL

073061202, Henry, IA

Built 1978 ADT: 21

155TH ST

Structurally Deficient

Over: CRANE CREEK

098132307, Howard, IA

Built 1937 ADT: 20

LOCAL LILAC AVE

Structurally Deficient

Over: BEAVER CREEK

100132502, Howard, IA

Built 1946 ADT: 26

LOCAL 25TH ST

Structurally Deficient

Over: STAFF CR

100141305, Howard, IA

Built 1944 ADT: 15

LOCAL

Structurally Deficient

Over: HOSKINS CREEK

087392602, Ida, IA

Built 1955 ADT: 26

LOCAL

Structurally Deficient

Over: CREEK

087393301, Ida, IA

Built 1964 ADT: 5

WOODBURY AVE

Structurally Deficient

Over: CREEK

088411902, Ida, IA

Built 1900 ADT: 50

LOCAL

Structurally Deficient

Over: BIRCH CREEK

078092502, Iowa, IA

Built 1963 ADT: 11

LOCAL

Structurally Deficient

Over: DRAINAGE DITCH

079110504, Iowa, IA

Built 1955 ADT: 20

FM LEGNO

Structurally Deficient

Over: DEVIL'S RUN

079122401, Iowa, IA

Built 1900

EAST LINE ST

Structurally Deficient

Over: BEERS CREEK

000000000, Jackson, IA

Built 1902 ADT: 20

LOCAL

Structurally Deficient

Over: SMALL CREEK

085E21704, Jackson, IA

Built 1940 ADT: 11

S 112TH AVE E

Structurally Deficient

Over: ELK CREEK

078182601, Jasper, IA

Built 1948 ADT: 20

W 36TH ST S

Structurally Deficient

Over: BUCK CREEK

078191908, Jasper, IA

Built 1928 ADT: 91

S 104TH AVE W

Structurally Deficient

Over: WALNUT CREEK

078212203, Jasper, IA

Built 1945 ADT: 5

S 64TH AVE E

Structurally Deficient

Over: SUGAR CREEK

079172505, Jasper, IA

Built 1933 ADT: 45

S 60TH AVE E

Structurally Deficient

Over: SMALL STREAM

079182803, Jasper, IA

Built 1932 ADT: 42

W 84TH ST S

Structurally Deficient

Over: RED ROCK CREEK

079203304, Jasper, IA

Built 1947 ADT: 11

Showing 19,501-19,550 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.