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

W 108TH ST S

Fair

Over: SQUAW CREEK

079212402, Jasper, IA

Built 1992 Load: 22.1 t ADT: 51

LOCAL

Fair

Over: POTATO CREEK

081181703, Jasper, IA

Built 1996 Load: 22.1 t ADT: 11

LOC 230TH AVE

Fair

Over: JDD #100, 131 & 93

094273502, Kossuth, IA

Built 1984 Load: 22.1 t ADT: 11

LOC 70TH AVE

Fair

Over: HINE CREEK

094290702, Kossuth, IA

Built 1971 Load: 22.1 t ADT: 15

LOC 50TH AVE

Fair

Over: TRULNER CREEK

094303502, Kossuth, IA

Built 1984 Load: 22.1 t ADT: 21

LOC 210TH ST

Fair

Over: PRAIRIE CREEK

095271001, Kossuth, IA

Built 1982 Load: 22.1 t ADT: 419

LOC 80TH AVE

Fair

Over: FOUR MILE CREEK

095292002, Kossuth, IA

Built 1976 Load: 22.1 t ADT: 21

LOC 100TH AVE

Fair

Over: FOUR MILE CREEK

095292702, Kossuth, IA

Built 1976 Load: 22.1 t ADT: 72

LOC 180TH ST

Fair

Over: FOUR MILE CREEK

095292901, Kossuth, IA

Built 1977 Load: 22.1 t ADT: 62

LOC 230TH AVE

Fair

Over: PLUM CREEK

096271102, Kossuth, IA

Built 1979 Load: 22.1 t ADT: 11

LOC 270TH ST

Fair

Over: LOTTS CREEK

096300901, Kossuth, IA

Built 1978 Load: 22.1 t ADT: 41

LOC 200TH AVE

Fair

Over: LINDER CREEK

097272902, Kossuth, IA

Built 1984 Load: 22.1 t ADT: 62

LOC 50TH AVE

Fair

Over: CALAMUS CREEK

097300202, Kossuth, IA

Built 1981 Load: 22.1 t ADT: 26

LOC 350TH ST

Fair

Over: BLACK CAT CREEK

098303101, Kossuth, IA

Built 1978 Load: 22.1 t ADT: 35

LOC 450TH ST

Fair

Over: W BR BLUE EARTH RIVER

099291203, Kossuth, IA

Built 1978 Load: 22.1 t ADT: 26

LOC 90TH AVE

Fair

Over: MUD CREEK

099292802, Kossuth, IA

Built 1975 Load: 22.1 t ADT: 5

LOC 70TH AVE

Fair

Over: MUD CREEK

099293002, Kossuth, IA

Built 1981 Load: 22.1 t ADT: 50

LOC 50TH AVE

Fair

Over: MUD CREEK

099301402, Kossuth, IA

Built 1977 Load: 22.1 t ADT: 30

LOC 480TH ST

Fair

Over: W BR BLUE EARTH RIVER

100282901, Kossuth, IA

Built 1973 Load: 22.1 t ADT: 41

LOC 140TH AVE

Fair

Over: W BR BLUE EARTH RIVER

100282902, Kossuth, IA

Built 1977 Load: 22.1 t ADT: 50

LOCAL

Fair

Over: SUTTON CREEK

069050304, Lee, IA

Built 1977 Load: 22.1 t ADT: 30

110TH ST

Fair

Over: PRAIRIE CREEK

069050505, Lee, IA

Built 1976 Load: 22.1 t ADT: 30

FM

Fair

Over: SMALL STREAM

076052803, Louisa, IA

Built 1960 Load: 22.1 t ADT: 100

LOCAL ROAD

Fair

Over: SPRING CREEK

099460902, Lyon, IA

Built 1971 Load: 22.1 t ADT: 30

FM

Fair

Over: CEDAR CREEK

076272011, Madison, IA

Built 1964 Load: 22.1 t ADT: 259

LOCAL

Fair

Over: OLIVE BRANCH CREEK

074140104, Mahaska, IA

Built 1971 Load: 22.1 t ADT: 50

LOCAL

Fair

Over: S COAL CREEK

074171104, Mahaska, IA

Built 1971 Load: 22.1 t ADT: 45

LOCAL

Fair

Over: BLUFF CREEK

074173303, Mahaska, IA

Built 1971 Load: 22.1 t ADT: 60

LOCAL

Fair

Over: MUCHAKINOCK CREEK

076172801, Mahaska, IA

Built 1973 Load: 22.1 t ADT: 26

LOCAL

Fair

Over: MIDDLE CREEK

077162602, Mahaska, IA

Built 1971 Load: 22.1 t ADT: 60

LOCAL

Fair

Over: MIDDLE CREEK

077162608, Mahaska, IA

Built 1971 Load: 22.1 t ADT: 50

LOCAL

Fair

Over: COON CREEK

075210801, Marion, IA

Built 1961 Load: 22.1 t ADT: 35

LOCAL

Fair

Over: LUTES CREEK

082173001, Marshall, IA

Built 1984 Load: 22.1 t ADT: 62

FM

Fair

Over: SMALL STREAM

083190504, Marshall, IA

Built 1984 Load: 22.1 t ADT: 177

LOCAL

Fair

Over: NICKOLSON CREEK

084172105, Marshall, IA

Built 1984 Load: 22.1 t ADT: 62

LOCAL

Fair

Over: DRAINAGE FROM LAKE MIAMI

073172901, Monroe, IA

Built 1965 Load: 22.1 t ADT: 20

LOCAL

Fair

Over: NISHNABOTNA TRIB

071392401, Montgomery, IA

Built 1965 Load: 22.1 t ADT: 51

FM-PINOAK ROAD

Fair

Over: WALNUT CREEK

076381001, Pottawattamie, IA

Built 1956 Load: 22.1 t ADT: 278

305TH ST

Fair

Over: CREEK

080E30907, Scott, IA

Built 1971 Load: 22.1 t ADT: 90

LOCAL

Fair

Over: TROUBLESOME CREEK

083131106, Tama, IA

Built 1950 Load: 22.1 t ADT: 33

LOCAL

Fair

Over: DEER CREEK

084153101, Tama, IA

Built 1985 Load: 22.1 t ADT: 20

LOCAL

Fair

Over: CREEK

069341304, Taylor, IA

Built 1975 Load: 22.1 t ADT: 40

LOCAL ROAD

Fair

Over: BR OTTER CREEK

075232306, Warren, IA

Built 1977 Load: 22.1 t ADT: 72

LOCAL

Fair

Over: FELTERS BRANCH

076241901, Warren, IA

Built 1977 Load: 22.1 t ADT: 72

FM

Fair

Over: STREAM

087420301, Woodbury, IA

Built 2006 Load: 22.1 t ADT: 20

LOCAL

Fair

Over: WHITE FOX CREEK

090250101, Wright, IA

Built 1982 Load: 22.1 t ADT: 15

LOCAL ROAD

Fair

Over: OTTER CREEK

093252801, Wright, IA

Built 1985 Load: 22.1 t ADT: 21

LOCAL

Fair

Over: FIELD STREAM

083340702, Carroll, IA

Built 1900 Load: 22.2 t ADT: 79

LOCAL 560TH ST.

Fair

Over: WILLOW CREEK

091411801, Cherokee, IA

Built 1989 Load: 22.2 t ADT: 20

LOCAL

Fair

Over: EAST LONG CK

071273606, Clarke, IA

Built 1975 Load: 22.2 t ADT: 29

Showing 3,201-3,250 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.