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

Fair

Over: CREEK

097092503, Winneshiek, IA

Built 1980 Load: 32.7 t ADT: 39

FM

Fair

Over: RUNNING CREEK

097102703, Winneshiek, IA

Built 1978 Load: 32.7 t ADT: 118

FM

Fair

Over: SMALL

097103404, Winneshiek, IA

Built 1978 Load: 32.7 t ADT: 34

LOCAL ROAD

Fair

Over: CREEK

098070910, Winneshiek, IA

Built 1900 Load: 32.7 t ADT: 49

LOCAL ROAD

Fair

Over: DRY RUN CREEK

098093402, Winneshiek, IA

Built 1971 Load: 32.7 t ADT: 33

FM

Fair

Over: DRAINAGE DITCH

098101802, Winneshiek, IA

Built 1976 Load: 32.7 t ADT: 59

LOCAL ROAD

Fair

Over: CREEK

099071002, Winneshiek, IA

Built 2006 Load: 32.7 t ADT: 33

LOCAL LEGNO

Fair

Over: CANOE CREEK

099073003, Winneshiek, IA

Built 2008 Load: 32.7 t ADT: 10

LOCAL

Fair

Over: SMALL STREAM

099081106, Winneshiek, IA

Built 1974 Load: 32.7 t ADT: 70

LOCAL

Fair

Over: SMALL

099083106, Winneshiek, IA

Built 1978 Load: 32.7 t ADT: 39

LOCAL

Fair

Over: SMALL

099092706, Winneshiek, IA

Built 1978 Load: 32.7 t ADT: 59

FM

Fair

Over: UPPER IOWA RIVER BRANCH

099101802, Winneshiek, IA

Built 1971 Load: 32.7 t ADT: 118

FM

Fair

Over: NORTH BEAR CREEK

100071904, Winneshiek, IA

Built 1993 Load: 32.7 t ADT: 786

LOCAL

Fair

Over: SMALL CREEK

100082703, Winneshiek, IA

Built 1976 Load: 32.7 t ADT: 70

360TH ST

Fair

Over: SMALL STREAM

100082903, Winneshiek, IA

Built 2000 Load: 32.7 t ADT: 88

LOCAL ROAD

Fair

Over: CREEK

100092204, Winneshiek, IA

Built 1970 Load: 32.7 t ADT: 44

MIDDLE SATTRE RD

Fair

Over: CREEK

099071908, Winneshiek, IA

Built 1976 Load: 32.7 t ADT: 187

IA 31

Fair

Over: STREAM

1.9 mi. N of SR D30, Woodbury, IA

Built 1956 Load: 32.7 t ADT: 1,070

FM

Fair

Over: SMALL CREEK

086420404, Woodbury, IA

Built 1978 Load: 32.7 t ADT: 350

LOCAL

Fair

Over: SMALL STREAM

0864225, Woodbury, IA

Built 1984 Load: 32.7 t ADT: 26

LOCAL

Fair

Over: MOREHEAD CREEK

0874213, Woodbury, IA

Built 1990 Load: 32.7 t ADT: 15

LOCAL

Fair

Over: REYNOLDS CREEK

0874233, Woodbury, IA

Built 1992 Load: 32.7 t ADT: 26

FM

Fair

Over: E.BR.WOLF CREEK

0874402, Woodbury, IA

Built 1992 Load: 32.7 t ADT: 399

FM

Fair

Over: ELLIOTT CREEK

088461404, Woodbury, IA

Built 1994 Load: 32.7 t ADT: 80

LOCAL

Fair

Over: DEER CREEK

088462703, Woodbury, IA

Built 1990 Load: 32.7 t ADT: 40

WHISPERING CREE

Fair

Over: MORNINGSIDE CREEK

000000000, Woodbury, IA

Built 1984 Load: 32.7 t ADT: 3,918

LOCAL

Fair

Over: LITTLE WHISKEY CREEK

088471101, Woodbury, IA

Built 1984 Load: 32.7 t ADT: 71

FM

Fair

Over: PIERSON CREEK

0894207, Woodbury, IA

Built 1976 Load: 32.7 t ADT: 211

KNOX AVE

Fair

Over: SMALL CREEK

089432002, Woodbury, IA

Built 1979 Load: 32.7 t ADT: 60

LOCAL

Fair

Over: STREAM

089452001, Woodbury, IA

Built 1977 Load: 32.7 t ADT: 15

LOCAL

Fair

Over: ELLIOTT CREEK

089452101, Woodbury, IA

Built 1977 Load: 32.7 t ADT: 34

LOCAL

Fair

Over: STREAM

089462301, Woodbury, IA

Built 1977 Load: 32.7 t ADT: 30

I-35

Fair

Over: GOOSE CREEK

3.3 mi. N County Road 105, Worth, IA

Built 1972 Load: 32.7 t ADT: 19,700

FM

Fair

Over: OTTER CREEK

093252201, Wright, IA

Built 2002 Load: 32.7 t ADT: 833

US 69

Fair

Over: STREAM

0.2 mi. N of N jct. IA 3, Wright, IA

Built 1962 Load: 32.7 t ADT: 2,480

LOCAL

Fair

Over: STREAM

074322801, Adair, IA

Built 2005 Load: 32.8 t ADT: 15

LOCAL (LWC)

Fair

Over: PRAIRIE CREEK

082110901, Benton, IA

Built 1990 Load: 32.8 t ADT: 45

LOCAL

Fair

Over: STEIN CK

084120803, Benton, IA

Built 1989 Load: 32.8 t ADT: 26

LOCAL (LWC)

Fair

Over: BIG CREEK

086121702, Benton, IA

Built 1988 Load: 32.8 t ADT: 34

LOC 100TH ST

Fair

Over: W BRANCH BUFFALO CK

090080501, Buchanan, IA

Built 1979 Load: 32.8 t ADT: 79

FM

Fair

Over: CAMP CREEK

087343301, Calhoun, IA

Built 1971 Load: 32.8 t ADT: 259

170TH ST.

Fair

Over: DRAINAGE

082E10901, Clinton, IA

Built 1987 Load: 32.8 t ADT: 21

120TH AVE.

Fair

Over: SMALL

082E10504, Clinton, IA

Built 1989 Load: 32.8 t ADT: 21

FM

Fair

Over: PARADISE CREEK

083402204, Crawford, IA

Built 1972 Load: 32.8 t ADT: 210

US 169

Fair

Over: BULGER CREEK & IAIS RR

1.1 mi. S of Jct. I-80, Dallas, IA

Built 1997 Load: 32.8 t ADT: 6,600

QUAKER / P30

Fair

Over: BUTTRICKS CREEK

083302606, Greene, IA

Built 1977 Load: 32.8 t ADT: 190

LOC SAWYER TR

Fair

Over: PICAYUNE CREEK

080410704, Harrison, IA

Built 1977 Load: 32.8 t ADT: 71

S 104TH AVE E

Fair

Over: ELK CREEK

078182205, Jasper, IA

Built 1979 Load: 32.8 t ADT: 80

LOCAL

Fair

Over: COMPETINE CK

072112105, Jefferson, IA

Built 1983 Load: 32.8 t ADT: 11

FM PRARE DU CHN

Fair

Over: RAPID CREEK

080063504, Johnson, IA

Built 1975 Load: 32.8 t ADT: 1,970

Showing 7,051-7,100 of 20,753 bridges

Related

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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.