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

110TH ST.

Poor

Over: SMALL

092091701, Fayette, IA

Built 1988 Load: 32.7 t ADT: 15

J AVE.

Poor

Over: SMALL STREAM

092082702, Fayette, IA

Built 1980 Load: 32.7 t ADT: 59

FM NETTLE AVE

Poor

Over: BEEDS CREEK

092202904, Franklin, IA

Built 1965 Load: 32.7 t ADT: 295

250 STREET

Poor

Over: GIBSON SLOUGH

068433003, Fremont, IA

Built 1953 Load: 32.7 t ADT: 79

195 AVENUE

Poor

Over: MULE SLOUGH

068431706, Fremont, IA

Built 2008 Load: 32.7 t ADT: 577

170 TH / E26

Poor

Over: DRAINAGE DITCH 110

084300801, Greene, IA

Built 1963 Load: 32.7 t ADT: 229

200 TH

Poor

Over: STREAM

084312801, Greene, IA

Built 1965 Load: 32.7 t ADT: 21

FM

Poor

Over: BRANCH BLACK HAWK CREEK

087150302, Grundy, IA

Built 1973 Load: 32.7 t ADT: 412

SPRINGBROOK SP

Poor

Over: STREAM

IN SPRINGBROOK ST. PK., Guthrie, IA

Built 1934 Load: 32.7 t

305TH ST

Poor

Over: KEG CREEK

078411301, Harrison, IA

Built 1957 Load: 32.7 t ADT: 20

L23 LAREDO AVE

Poor

Over: STEER CREEK

.75 MI S of 147th on L23, Harrison, IA

Built 1942 Load: 32.7 t ADT: 139

FM

Poor

Over: SKUNK RIVER

070052820, Henry, IA

Built 1976 Load: 32.7 t ADT: 590

SPRUCE AVE

Poor

Over: STREAM

072081910, Jefferson, IA

Built 1950 Load: 32.7 t ADT: 100

COUNTY RD X-31

Poor

Over: MINO CREEK

085043404, Jones, IA

Built 1966 Load: 32.7 t ADT: 520

CO RD W15

Poor

Over: SMALL STREAM

074100206, Keokuk, IA

Built 1932 Load: 32.7 t ADT: 620

HICKORYVALLEYRD

Poor

Over: WEST OTTER CREEK

085071803, Linn, IA

Built 1987 Load: 32.7 t ADT: 11

G76

Poor

Over: SMALL STREAM

074191903, Marion, IA

Built 1964 Load: 32.7 t ADT: 400

150TH ST

Poor

Over: BURNETT CR

085173301, Marshall, IA

Built 1979 Load: 32.7 t ADT: 47

SO 3RD AVE

Poor

Over: ANSON CREEK

083181102, Marshall, IA

Built 1979 Load: 32.7 t ADT: 418

LCL-RAINS AVE

Poor

Over: SPRING VALLEY CREEK

071423601, Mills, IA

Built 1970 Load: 32.7 t ADT: 20

LCL-410TH ST

Poor

Over: LOCAL CREEK

072403606, Mills, IA

Built 1972 Load: 32.7 t ADT: 51

LCL-JESUP AVE

Poor

Over: MAJOR DRAINAGE

072432003, Mills, IA

Built 1970 Load: 32.7 t ADT: 133

FA-BARRUS RD

Poor

Over: PONY CREEK

073431401, Mills, IA

Built 1969 Load: 32.7 t ADT: 1,524

FM

Poor

Over: WALNUT CREEK

072392703, Montgomery, IA

Built 1967 Load: 32.7 t ADT: 750

SEC RD

Poor

Over: JORDAN CREEK

094390303, O'Brien, IA

Built 1916 Load: 32.7 t

NUTMEG AVENUE

Poor

Over: EAST MILL CREEK

067372904, Page, IA

Built 1989 Load: 32.7 t ADT: 11

LOCAL ROAD

Poor

Over: MUD CREEK

078220503, Polk, IA

Built 1925 Load: 32.7 t ADT: 20

ROAD L-34

Poor

Over: STREAM

075430218, Pottawattamie, IA

Built 1965 Load: 32.7 t ADT: 20

BROADWAY TO RR

Poor

Over: INDIAN CREEK

Creektop, CNRR to UPRR, Pottawattamie, IA

Built 1937 Load: 32.7 t ADT: 126

CREEK TOP RD

Poor

Over: INDIAN CREEK

Creek Top, 9th to 8th St, Pottawattamie, IA

Built 1937 Load: 32.7 t ADT: 2,027

NORTH 13TH STREET

Poor

Over: INDIAN CREEK

Outlet @ Broadway to CNRR, Pottawattamie, IA

Built 1937 Load: 32.7 t ADT: 2,027

FM

Poor

Over: NO NAME CREEK

089372101, Sac, IA

Built 1925 Load: 32.7 t ADT: 249

FM

Poor

Over: SMALL STREAM

071303502, Union, IA

Built 1985 Load: 32.7 t ADT: 71

FM

Poor

Over: STREAM

070101205, Van Buren, IA

Built 1956 Load: 32.7 t ADT: 260

LOCAL

Poor

Over: CREEK

070110603, Van Buren, IA

Built 1972 Load: 32.7 t ADT: 26

LOCAL

Poor

Over: OVER BNSF RR

072133406, Wapello, IA

Built 1994 Load: 32.7 t ADT: 187

FM

Poor

Over: TROUT RIVER

098072703, Winneshiek, IA

Built 1958 Load: 32.7 t ADT: 697

MEADOWLARK RD

Poor

Over: CREEK

099083204, Winneshiek, IA

Built 1976 Load: 32.7 t ADT: 128

LOCAL

Poor

Over: CREEK

099101005, Winneshiek, IA

Built 1977 Load: 32.7 t ADT: 44

FM

Poor

Over: ELLIOTT CREEK

089450901, Woodbury, IA

Built 1958 Load: 32.7 t ADT: 797

FM

Poor

Over: SOAP CREEK

070162906, Appanoose, IA

Built 1970 Load: 32.8 t ADT: 790

LOCAL - WICHITA

Poor

Over: NODAWAY RIVER

074352903, Cass, IA

Built 1988 Load: 32.8 t ADT: 26

FM - 690TH

Poor

Over: SEVENMILE CREEK

075351502, Cass, IA

Built 1971 Load: 32.8 t ADT: 468

FM

Poor

Over: WOLF CREEK, BRANCH

086170801, Grundy, IA

Built 1972 Load: 32.8 t ADT: 285

FM

Poor

Over: SKUNK RIVER

086242503, Hamilton, IA

Built 1974 Load: 32.8 t ADT: 698

FM

Poor

Over: STREAM

097332104, Palo Alto, IA

Built 1977 Load: 32.8 t ADT: 31

LOCAL

Poor

Over: MUD CREEK

084111502, Benton, IA

Built 1976 Load: 33.0 t ADT: 26

FM

Poor

Over: SMALL STREAM

088082109, Buchanan, IA

Built 1952 Load: 33.0 t ADT: 776

FM

Poor

Over: SMALL

090381901, Buena Vista, IA

Built 1978 Load: 33.0 t ADT: 390

FM

Poor

Over: CREEK

091380502, Buena Vista, IA

Built 1970 Load: 33.0 t ADT: 469

Showing 19,101-19,150 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.