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

Poor

Over: BUFFALO CREEK

098252002, Winnebago, IA

Built 1975 Load: 21.0 t ADT: 26

LOCAL

Poor

Over: WRIGHT CREEK

088422302, Woodbury, IA

Built 1950 Load: 21.0 t ADT: 11

LOCAL

Poor

Over: BR RACCOON RIVER

091361602, Buena Vista, IA

Built 1925 Load: 21.1 t ADT: 20

LOCAL

Poor

Over: BROOKS CREEK

092373102, Buena Vista, IA

Built 1918 Load: 21.1 t ADT: 30

FM

Poor

Over: SMALL STREAM

069040608, Des Moines, IA

Built 1949 Load: 21.1 t ADT: 60

LOCAL

Poor

Over: BURR OAK CREEK

080181001, Jasper, IA

Built 1915 Load: 21.1 t ADT: 51

LOCAL

Poor

Over: SMALL STREAM

076273611, Madison, IA

Built 1982 Load: 21.1 t ADT: 71

LOCAL

Poor

Over: DRAINAGE

076140301, Mahaska, IA

Built 1956 Load: 21.1 t ADT: 5

LOCAL

Poor

Over: MINERVA CR

084200702, Marshall, IA

Built 1949 Load: 21.1 t ADT: 26

ROSE AVENUE

Poor

Over: NO BUSINESS CREEK

068373604, Page, IA

Built 1900 Load: 21.1 t ADT: 170

LOMBARDY ROAD

Poor

Over: LITTLE SILVER CREEK

076412701, Pottawattamie, IA

Built 1989 Load: 21.1 t ADT: 20

LOCAL ROAD

Poor

Over: PAINTER CREEK

075252402, Warren, IA

Built 1952 Load: 21.1 t ADT: 11

LOCAL

Poor

Over: SMITH CREEK

077092406, Washington, IA

Built 1930 Load: 21.1 t ADT: 110

LOCAL

Poor

Over: BEAR CK

086101105, Benton, IA

Built 1972 Load: 21.2 t ADT: 20

200TH ST

Poor

Over: BUCK CREEK

092112805, Bremer, IA

Built 1970 Load: 21.2 t ADT: 26

LOCAL

Poor

Over: BR RACCOON RIVER

093362504, Buena Vista, IA

Built 1971 Load: 21.2 t ADT: 30

LOCAL

Poor

Over: D.D. NO 83

088310701, Calhoun, IA

Built 1900 Load: 21.2 t ADT: 15

LOCAL

Poor

Over: DD 9-13

089321502, Calhoun, IA

Built 1900 Load: 21.2 t ADT: 40

LOCAL

Poor

Over: STREAM

070152403, Davis, IA

Built 1973 Load: 21.2 t ADT: 15

LOCAL

Poor

Over: DRAINAGE DITCH

091293302, Humboldt, IA

Built 1948 Load: 21.2 t ADT: 15

FM

Poor

Over: TOM CREEK

077292702, Madison, IA

Built 1962 Load: 21.2 t ADT: 597

LOCAL

Poor

Over: DRAINAGE

075161707, Mahaska, IA

Built 1958 Load: 21.2 t ADT: 131

LOCAL

Poor

Over: AVERY CREEK

071160904, Monroe, IA

Built 1967 Load: 21.2 t ADT: 26

LOCAL

Poor

Over: NISHNABOTNA TRIB

073381501, Montgomery, IA

Built 1970 Load: 21.2 t ADT: 5

S AVENUE

Poor

Over: STREAM

070360502, Page, IA

Built 1984 Load: 21.2 t ADT: 20

120TH ST

Poor

Over: INDIAN CREEK

093481401, Plymouth, IA

Built 1900 Load: 21.2 t ADT: 20

100TH ST

Poor

Over: SMALL STREAM

085230101, Story, IA

Built 1917 Load: 21.2 t ADT: 30

FM

Poor

Over: STONY CREEK

074223403, Warren, IA

Built 1958 Load: 21.2 t ADT: 400

LOCAL

Poor

Over: TEN MILE CREEK

098090806, Winneshiek, IA

Built 1900 Load: 21.2 t ADT: 118

LOCAL - 730TH

Poor

Over: WATERWAY

077343204, Cass, IA

Built 1958 Load: 21.3 t ADT: 30

240TH ST

Poor

Over: BR GOWER CR

080041801, Cedar, IA

Built 1924 Load: 21.3 t ADT: 50

LOCAL 540TH ST

Poor

Over: WEST FORK LITTLE SIOUX

091420301, Cherokee, IA

Built 1925 Load: 21.3 t ADT: 20

LOCAL-G AVE.

Poor

Over: SMALL CREEK

092413102, Cherokee, IA

Built 1924 Load: 21.3 t ADT: 50

FM

Poor

Over: FROST CREEK

080332602, Guthrie, IA

Built 1959 Load: 21.3 t ADT: 15

TIMBER AVE

Poor

Over: TURKEY RIVER

097110502, Howard, IA

Built 1987 Load: 21.3 t ADT: 48

LOC 100TH AVE

Poor

Over: D.D.#60

100291002, Kossuth, IA

Built 1984 Load: 21.3 t ADT: 21

LOCAL

Poor

Over: SMALL STREAM

073041401, Louisa, IA

Built 1943 Load: 21.3 t ADT: 47

LOCAL

Poor

Over: BRUSH CREEK

079163103, Poweshiek, IA

Built 1958 Load: 21.3 t ADT: 34

FM

Poor

Over: EAST CREEK

067282501, Ringgold, IA

Built 1958 Load: 21.3 t ADT: 11

LOCAL

Poor

Over: EAST BRANCH SALT CREEK

084131201, Tama, IA

Built 1936 Load: 21.3 t ADT: 39

270TH ST

Poor

Over: CRANE CREEK

091123301, Bremer, IA

Built 1900 Load: 21.4 t ADT: 20

LOCAL

Poor

Over: LAKE CREEK

089323501, Calhoun, IA

Built 1917 Load: 21.4 t ADT: 20

LOCAL- U AVE

Poor

Over: PITCHER CR

090390902, Cherokee, IA

Built 1926 Load: 21.4 t ADT: 15

FM

Poor

Over: SMALL STREAM

089E12004, Dubuque, IA

Built 1984 Load: 21.4 t ADT: 412

LOC 150TH AVE

Poor

Over: PURCELL CREEK

095280902, Kossuth, IA

Built 1975 Load: 21.4 t ADT: 50

LOCAL

Poor

Over: DRAINAGE

075270305, Madison, IA

Built 1952 Load: 21.4 t ADT: 20

LOCAL

Poor

Over: N COAL CREEK

074171702, Mahaska, IA

Built 1956 Load: 21.4 t ADT: 71

LOCAL

Poor

Over: MUCHAKINOCK CREEK

076173518, Mahaska, IA

Built 1949 Load: 21.4 t ADT: 180

LOCAL

Poor

Over: CLEAR CREEK

083203204, Marshall, IA

Built 1950 Load: 21.4 t ADT: 11

LOCAL

Poor

Over: STREAM

099420502, Osceola, IA

Built 1943 Load: 21.4 t ADT: 21

Showing 18,151-18,200 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.