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

ORANGE ST

Fair

Over: DRAINAGE DITCH

7904060503, Cedar, IA

Built 2005 Load: 32.7 t ADT: 82

240TH

Fair

Over: CHESALEA CREEK

096202901, Cerro Gordo, IA

Built 2004 Load: 32.7 t ADT: 1,571

JONQUIL

Fair

Over: WILLOW CREEK

096211504, Cerro Gordo, IA

Built 1997 Load: 32.7 t ADT: 577

NETTLE

Fair

Over: DRAINAGE

095201702, Cerro Gordo, IA

Built 2005 Load: 32.7 t ADT: 30

CERRO GORDO ST

Fair

Over: SMALL STREAM

0.1 MI EAST OF I-35, Cerro Gordo, IA

Built 1972 Load: 32.7 t ADT: 34

LOCAL- K AVE

Fair

Over: CREEK

090412602, Cherokee, IA

Built 2002 Load: 32.7 t ADT: 11

N AVE

Fair

Over: PERRY CREEK

091400802, Cherokee, IA

Built 2002 Load: 32.7 t ADT: 11

LOCAL-Y AVE.

Fair

Over: BR MAPLE RIVER

092391202, Cherokee, IA

Built 1982 Load: 32.7 t ADT: 20

LOCAL-C AVE.

Fair

Over: BRANCH FIDDLE CREEK

092422802, Cherokee, IA

Built 1981 Load: 32.7 t ADT: 50

FM

Fair

Over: BRANCH TWO MILE CREEK

094141202, Chickasaw, IA

Built 1997 Load: 32.7 t ADT: 550

FM

Fair

Over: SIMPSON CREEK

095112702, Chickasaw, IA

Built 1986 Load: 32.7 t ADT: 589

LOCAL

Fair

Over: CREEK

096121901, Chickasaw, IA

Built 1999 Load: 32.7 t ADT: 47

LOCAL

Fair

Over: BR LITTLE TURKEY CREEK

097113201, Chickasaw, IA

Built 2004 Load: 32.7 t ADT: 511

FM

Fair

Over: CRANE CREEK

097123307, Chickasaw, IA

Built 1951 Load: 32.7 t ADT: 648

LOCAL

Fair

Over: STREAM (LWC)

072241204, Clarke, IA

Built 1998 Load: 32.7 t ADT: 34

FM

Fair

Over: SQUAW CREEK

072250603, Clarke, IA

Built 1994 Load: 32.7 t ADT: 658

FM

Fair

Over: SOUTH WEST CREEK

072261301, Clarke, IA

Built 1968 Load: 32.7 t ADT: 180

FM

Fair

Over: WHITE BREAST CREEK

072262102, Clarke, IA

Built 1985 Load: 32.7 t ADT: 240

GRIFFITH

Fair

Over: SMALL STREAM

072242703, Clarke, IA

Built 1969 Load: 32.7 t ADT: 67

490TH ST

Fair

Over: MONTGOMERY CREEK

094353001, Clay, IA

Built 1990 Load: 32.7 t ADT: 46

190TH AVE

Fair

Over: STREAM

094371002, Clay, IA

Built 1999 Load: 32.7 t ADT: 46

225TH AVE

Fair

Over: SMALL STREAM

095360604, Clay, IA

Built 1978 Load: 32.7 t ADT: 81

FM 440TH ST

Fair

Over: SMALL

095373201, Clay, IA

Built 1988 Load: 32.7 t ADT: 469

FM 400TH ST

Fair

Over: WILLOW CREEK

095380801, Clay, IA

Built 1968 Load: 32.7 t ADT: 797

370TH ST

Fair

Over: STREAM

096352601, Clay, IA

Built 2001 Load: 32.7 t ADT: 47

US 71

Fair

Over: BR OF LITTLE MEADOW CRK

0.8 mi. N of N jct. US 18, Clay, IA

Built 1990 Load: 32.7 t ADT: 11,400

GRANDVIEW RD

Fair

Over: SMALL STREAM

092041808, Clayton, IA

Built 1984 Load: 32.7 t ADT: 874

DOMINO RD

Fair

Over: STREAM

093052907, Clayton, IA

Built 1920 Load: 32.7 t ADT: 619

190TH ST

Fair

Over: STREAM

094042101, Clayton, IA

Built 1988 Load: 32.7 t ADT: 206

145TH ST

Fair

Over: SMALL CREEK

095052903, Clayton, IA

Built 1986 Load: 32.7 t ADT: 69

IA 56

Fair

Over: PONY CREEK

0.1 MI. W OF JCT. IA 13, Clayton, IA

Built 1983 Load: 32.7 t ADT: 1,280

230TH ST

Fair

Over: CREEK

081E51201, Clinton, IA

Built 1952 Load: 32.7 t ADT: 82

160TH ST

Fair

Over: STREAM

082E40501, Clinton, IA

Built 1962 Load: 32.7 t ADT: 21

400TH AVE.

Fair

Over: CREEK

083E63002, Clinton, IA

Built 1958 Load: 32.7 t ADT: 40

FM

Fair

Over: MALONY CREEK

083372502, Crawford, IA

Built 1985 Load: 32.7 t ADT: 180

R 30 (W AVE)

Fair

Over: WALNUT CREEK

079261104, Dallas, IA

Built 1975 Load: 32.7 t ADT: 3,018

W AVE

Fair

Over: LITTLE WALNUT CREEK

079262300, Dallas, IA

Built 1975 Load: 32.7 t ADT: 3,612

FM

Fair

Over: TRIB. TO SUGAR CREEK

078260502, Dallas, IA

Built 2000 Load: 32.7 t ADT: 3,636

UTICA TRAIL

Fair

Over: TRIB OF RACCOON RIVER

078263105, Dallas, IA

Built 1994 Load: 32.7 t ADT: 289

68TH STREET

Fair

Over: CREEK

O54200475, Dallas, IA

Built 2003 Load: 32.7 t ADT: 1,216

BROOKVIEW LN

Fair

Over: DD

078272700, Dallas, IA

Built 2004 Load: 32.7 t ADT: 58

LOCAL

Fair

Over: FOX RIVER TRIBUTARY

068131201, Davis, IA

Built 1976 Load: 32.7 t ADT: 60

LOCAL

Fair

Over: BEAR CREEK

070150406, Davis, IA

Built 1999 Load: 32.7 t ADT: 30

MAIN ST

Fair

Over: MORGAN BRANCH

070131401, Davis, IA

Built 1970 Load: 32.7 t ADT: 720

FM

Fair

Over: LICK BRANCH

067241703, Decatur, IA

Built 1989 Load: 32.7 t ADT: 170

FM

Fair

Over: STREAM

067242103, Decatur, IA

Built 1990 Load: 32.7 t ADT: 170

FM

Fair

Over: TURKEY RUN CREEK

068240504, Decatur, IA

Built 1992 Load: 32.7 t ADT: 15

FM

Fair

Over: LITTLE RIVER

069250601, Decatur, IA

Built 1979 Load: 32.7 t ADT: 428

FM

Fair

Over: LITTLE RIVER

069260201, Decatur, IA

Built 1979 Load: 32.7 t ADT: 428

LOCAL

Fair

Over: MORMON POOL

070242702, Decatur, IA

Built 1995 Load: 32.7 t ADT: 51

Showing 6,401-6,450 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.