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

Structurally Deficient

Over: LITTLE WHITEBREAST CREEK

073211901, Lucas, IA

Built 1933 ADT: 11

LOCAL

Structurally Deficient

Over: BR OF ENGLISH CREEK

073212103, Lucas, IA

Built 1939 ADT: 5

LOCAL

Structurally Deficient

Over: BR OF ENGLISH CREEK

073212606, Lucas, IA

Built 1938 ADT: 21

LOCAL

Structurally Deficient

Over: STONY CREEK

073220902, Lucas, IA

Built 1965 ADT: 5

LOCAL

Structurally Deficient

Over: BR LITTLE WHITEBREAST CR

073221206, Lucas, IA

Built 1929 ADT: 11

LOCAL

Structurally Deficient

Over: LITTLE WHITEBREAST CREEK

073221304, Lucas, IA

Built 1936 ADT: 11

LOCAL

Structurally Deficient

Over: STONY FORK

073221708, Lucas, IA

Built 1999 ADT: 5

LOCAL

Structurally Deficient

Over: INDIAN CREEK

073222806, Lucas, IA

Built 1956 ADT: 30

LOCAL

Structurally Deficient

Over: OTTER CREEK

073230501, Lucas, IA

Built 1910 ADT: 26

LOCAL

Structurally Deficient

Over: S OTTER CREEK

073230904, Lucas, IA

Built 1970 ADT: 5

LOCAL

Structurally Deficient

Over: BR OF OTTER CREEK

073231707, Lucas, IA

Built 1953 ADT: 11

LOCAL

Structurally Deficient

Over: DR TO ENGLISH CREEK

073211202, Lucas, IA

Built 1900 ADT: 21

LOCAL ROAD

Structurally Deficient

Over: RAT CREEK

098432302, Lyon, IA

Built 1954 ADT: 26

LOCAL ROAD

Structurally Deficient

Over: OTTER CREEK

098433302, Lyon, IA

Built 1900 ADT: 30

LOCAL ROAD

Structurally Deficient

Over: OVER FLOW

098433302, Lyon, IA

Built 1900 ADT: 30

LOCAL ROAD

Structurally Deficient

Over: OTTER CREEK

098443502, Lyon, IA

Built 1900 ADT: 30

LOCAL ROAD

Structurally Deficient

Over: EMERY CREEK

098450102, Lyon, IA

Built 1900 ADT: 26

LOCAL ROAD

Structurally Deficient

Over: SMALL STREAM

098460701, Lyon, IA

Built 1900 ADT: 41

LOCAL

Structurally Deficient

Over: ROCK RIVER

098462303, Lyon, IA

Built 1900 ADT: 62

LOCAL ROAD

Structurally Deficient

Over: HEFFERMAN CREEK

098472802, Lyon, IA

Built 1900 ADT: 11

220TH ST

Structurally Deficient

Over: BIG SIOUX RIVER

098480804, Lyon, IA

Built 1925 ADT: 46

LOCAL ROAD

Structurally Deficient

Over: LITTLE ROCK RIVER

099430901, Lyon, IA

Built 1900 ADT: 71

LOCAL ROAD

Structurally Deficient

Over: KLONDIKE CREEK

099481201, Lyon, IA

Built 1900 ADT: 41

LOCAL ROAD

Structurally Deficient

Over: TOM CREEK

100442902, Lyon, IA

Built 1900 ADT: 15

N 2ND AVE

Structurally Deficient

Over: SMALL STREAM

100453304, Lyon, IA

Built 1900 ADT: 346

GRANDVIEW TRL

Structurally Deficient

Over: N CLANTON CREEK

074283505, Madison, IA

Built 1895 ADT: 5

LOCAL RD

Structurally Deficient

Over: N FORK CLANTON CREEK

074280906, Madison, IA

Built 1900 ADT: 15

FM

Structurally Deficient

Over: CLANTON CREEK

075261202, Madison, IA

Built 1932 ADT: 450

FM

Structurally Deficient

Over: OVERFLOW CLANTON CREEK

075261202, Madison, IA

Built 1932 ADT: 450

LOCAL RD

Structurally Deficient

Over: NORTH RIVER

076291104, Madison, IA

Built 1909 ADT: 26

LOCAL

Structurally Deficient

Over: BADGER CREEK

077262401, Madison, IA

Built 1890 ADT: 40

LOCAL RD

Structurally Deficient

Over: DRAINAGE

077273204, Madison, IA

Built 1956 ADT: 11

LOCAL RD

Structurally Deficient

Over: JIM CREEK

077291203, Madison, IA

Built 1895 ADT: 20

LOCAL

Structurally Deficient

Over: DRAINAGE

074142701, Mahaska, IA

Built 1948 ADT: 45

LOCAL

Structurally Deficient

Over: BLUFF CREEK

074172706, Mahaska, IA

Built 1973 ADT: 11

LOCAL

Structurally Deficient

Over: S COAL CREEK

074173003, Mahaska, IA

Built 1957 ADT: 15

FM

Structurally Deficient

Over: N SKUNK RIVER

076141001, Mahaska, IA

Built 1966 ADT: 370

FM

Structurally Deficient

Over: N SKUNK RIVER OVERFLOW

076141001, Mahaska, IA

Built 1961 ADT: 370

LOCAL

Structurally Deficient

Over: DRAINAGE

076150501, Mahaska, IA

Built 1950 ADT: 80

LOCAL

Structurally Deficient

Over: MITCHELL CREEK

076161603, Mahaska, IA

Built 1936 ADT: 26

LOCAL

Structurally Deficient

Over: PAINTER CREEK

076163507, Mahaska, IA

Built 1951 ADT: 90

140TH ST

Structurally Deficient

Over: CEDAR CREEK

077142505, Mahaska, IA

Built 1950 ADT: 10

FM

Structurally Deficient

Over: DRAINAGE

077153203, Mahaska, IA

Built 1954 ADT: 30

FIELD ENTRANCE

Structurally Deficient

Over: MUCHAKINOCK CREEK(SDB)

074162403, Mahaska, IA

Built 1952 ADT: 10

FM

Structurally Deficient

Over: SOUTH TIMBER CREEK

082180902, Marshall, IA

Built 1957 ADT: 39

LOCAL

Structurally Deficient

Over: BR BURNETT CR

085173101, Marshall, IA

Built 1977 ADT: 5

LOCAL

Structurally Deficient

Over: DOWD CREEK

085190103, Marshall, IA

Built 1916 ADT: 16

FM

Structurally Deficient

Over: CREEK

085190602, Marshall, IA

Built 1918 ADT: 25

LCL-JAHNKE AVE

Structurally Deficient

Over: SILVER CREEK

072411903, Mills, IA

Built 1938 ADT: 5

LCL-COMPASS AVE

Structurally Deficient

Over: FARM CREEK

073401407, Mills, IA

Built 1963 ADT: 5

Showing 19,601-19,650 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.