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: SMALL STREAM

073132004, Wapello, IA

Built 1986 Load: 32.7 t ADT: 41

FM

Fair

Over: BRANCH DES MOINES RIVER

073143006, Wapello, IA

Built 1995 Load: 32.7 t ADT: 1,300

FM

Fair

Over: STREAM

072152706, Wapello, IA

Built 1981 Load: 32.7 t ADT: 70

I 35

Fair

Over: BROAD HORN CREEK

1.0 MI. N OF SR G-64, Warren, IA

Built 1957 Load: 32.7 t ADT: 21,000

I-35

Fair

Over: DRAINAGE DITCH

5.7 MI. S OF JCT. IA 92, Warren, IA

Built 1958 Load: 32.7 t ADT: 21,000

LOCAL ROAD

Fair

Over: WOLF CREEK

074221304, Warren, IA

Built 1994 Load: 32.7 t ADT: 15

FM

Fair

Over: WINN BRANCH WB CREEK

074222407, Warren, IA

Built 2003 Load: 32.7 t ADT: 500

LOCAL ROAD

Fair

Over: TURKEY CREEK

074230805, Warren, IA

Built 1975 Load: 32.7 t ADT: 11

FM

Fair

Over: INDIAN CREEK

074231810, Warren, IA

Built 1983 Load: 32.7 t ADT: 50

FM

Fair

Over: SKINAWAY CREEK

074242705, Warren, IA

Built 1986 Load: 32.7 t ADT: 499

FM

Fair

Over: MIDDLE RIVER

075250501, Warren, IA

Built 1976 Load: 32.7 t ADT: 34

LOCAL ROAD

Fair

Over: BRANCH SOUTH RIVER

075251204, Warren, IA

Built 1977 Load: 32.7 t ADT: 103

LOCAL ROAD

Fair

Over: BRANCH SOUTH RIVER

076233603, Warren, IA

Built 1975 Load: 32.7 t ADT: 134

LOCAL

Fair

Over: BRANCH MIDDLE RIVER

077242503, Warren, IA

Built 1988 Load: 32.7 t ADT: 103

G24

Fair

Over: BRANCH NORTH RIVER

077243101, Warren, IA

Built 1973 Load: 32.7 t ADT: 1,783

40TH AVE

Fair

Over: MID SOUTH CREEK

077251002, Warren, IA

Built 1983 Load: 32.7 t ADT: 932

CO RD W64

Fair

Over: BIG SLOUGH CREEK

074060308, Washington, IA

Built 1982 Load: 32.7 t ADT: 220

LOCAL

Fair

Over: SM STREAM

074071103, Washington, IA

Built 1992 Load: 32.7 t ADT: 15

FM

Fair

Over: SM STREAM

074092904, Washington, IA

Built 1974 Load: 32.7 t ADT: 180

LOCAL

Fair

Over: SMALL STREAM

074093004, Washington, IA

Built 1987 Load: 32.7 t ADT: 50

FM

Fair

Over: BURR OAK CREEK

074093604, Washington, IA

Built 1991 Load: 32.7 t ADT: 1,100

LOCAL ROAD

Fair

Over: CEDAR CREEK

075073103, Washington, IA

Built 1999 Load: 32.7 t ADT: 50

FM

Fair

Over: CLEMONS CREEK

075080502, Washington, IA

Built 1990 Load: 32.7 t ADT: 260

LOCAL ROAD

Fair

Over: CLEMONS CREEK

075080801, Washington, IA

Built 1991 Load: 32.7 t ADT: 20

LOCAL

Fair

Over: SMALL STREAM

075082202, Washington, IA

Built 1987 Load: 32.7 t ADT: 26

FM

Fair

Over: DAVIS CREEK

077063204, Washington, IA

Built 1994 Load: 32.7 t ADT: 80

LOCAL ROAD

Fair

Over: SMALL STREAM

077081503, Washington, IA

Built 1988 Load: 32.7 t ADT: 71

FM

Fair

Over: SOUTH ENGLISH RIVER

077090706, Washington, IA

Built 1993 Load: 32.7 t ADT: 50

S60 235TH ST

Fair

Over: SMALL NATURAL STREAM

068201412, Wayne, IA

Built 1957 Load: 32.7 t ADT: 980

LOCAL

Fair

Over: BRANCH OF LOCUST CREEK

067201005, Wayne, IA

Built 1978 Load: 32.7 t ADT: 26

LOCAL

Fair

Over: STREAM

067212401, Wayne, IA

Built 1988 Load: 32.7 t ADT: 20

FM

Fair

Over: MEDICINE CREEK

067221101, Wayne, IA

Built 1996 Load: 32.7 t ADT: 110

LOCAL

Fair

Over: LITTLE MUDDY

067231505, Wayne, IA

Built 1990 Load: 32.7 t ADT: 20

FM

Fair

Over: GRAND RIVER

067232203, Wayne, IA

Built 1998 Load: 32.7 t ADT: 80

FM

Fair

Over: FORK WALNUT CREEK

068200303, Wayne, IA

Built 1987 Load: 32.7 t ADT: 20

FM

Fair

Over: SMALL STREAM

068231105, Wayne, IA

Built 1972 Load: 32.7 t ADT: 230

140TH ST

Fair

Over: JACKSON CREEK

069212904, Wayne, IA

Built 1988 Load: 32.7 t ADT: 130

FM

Fair

Over: STEELE STREAM

069230506, Wayne, IA

Built 1977 Load: 32.7 t ADT: 15

FM

Fair

Over: SMALL

070202602, Wayne, IA

Built 1983 Load: 32.7 t ADT: 310

LOCAL (OLD IA 2

Fair

Over: S CHARITON RIVER

069222801, Wayne, IA

Built 1999 Load: 32.7 t ADT: 90

D 36

Fair

Over: SPRING CREEK

088301401, Webster, IA

Built 1984 Load: 32.7 t ADT: 1,547

D20 200TH ST

Fair

Over: BRUSHY CREEK

089272601, Webster, IA

Built 1977 Load: 32.7 t ADT: 2,384

LOCAL

Fair

Over: BUTTRICK CREEK

086292201, Webster, IA

Built 1993 Load: 32.7 t ADT: 35

FM

Fair

Over: HOLIDAY CREEK

088281007, Webster, IA

Built 1974 Load: 32.7 t ADT: 538

FM

Fair

Over: BADGER CREEK

090282904, Webster, IA

Built 1993 Load: 32.7 t ADT: 2,035

US 52

Fair

Over: DRY RUN

0.3 mi. N of Jct. Iowa #9, Winneshiek, IA

Built 1963 Load: 32.7 t ADT: 4,230

FM

Fair

Over: TANGEN CREEK

096082804, Winneshiek, IA

Built 1935 Load: 32.7 t ADT: 59

LOCAL

Fair

Over: CREEK

096090101, Winneshiek, IA

Built 1977 Load: 32.7 t ADT: 78

LOCAL ROAD

Fair

Over: CREEK

096101501, Winneshiek, IA

Built 1900 Load: 32.7 t ADT: 39

LOCAL ROAD

Fair

Over: CREEK

096102501, Winneshiek, IA

Built 1975 Load: 32.7 t ADT: 33

Showing 7,001-7,050 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.