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

120TH ST

Good

Over: WILLOW CREEK

093441501, Plymouth, IA

Built 1989 Load: 52.7 t ADT: 5

PIONEER AVE

Good

Over: WILLOW CREEK

093441502, Plymouth, IA

Built 1990 Load: 52.7 t ADT: 15

LOCAL

Good

Over: PLUM CREEK

070303001, Ringgold, IA

Built 1997 Load: 52.7 t ADT: 5

FM

Good

Over: INDIAN CREEK

087362001, Sac, IA

Built 1998 Load: 52.7 t ADT: 26

LOCAL

Good

Over: STREAM

087362901, Sac, IA

Built 1993 Load: 52.7 t ADT: 45

LOCAL

Good

Over: STREAM

070102205, Van Buren, IA

Built 2006 Load: 52.7 t ADT: 30

LOCAL

Good

Over: BRANCH CEDAR CREEK

073140102, Wapello, IA

Built 2002 Load: 52.7 t ADT: 73

LOCAL ROAD

Good

Over: WONDER CREEK

097102404, Winneshiek, IA

Built 1991 Load: 52.7 t ADT: 44

LOCAL ROAD

Good

Over: COON CREEK

098071303, Winneshiek, IA

Built 1992 Load: 52.7 t ADT: 44

FM

Good

Over: UPPER IOWA RIVER

099100204, Winneshiek, IA

Built 2003 Load: 52.7 t ADT: 118

128TH AVE

Good

Over: NORTH BEAR CREEK

100071104, Winneshiek, IA

Built 2006 Load: 52.7 t ADT: 20

MIDDLE SATTRE RD

Good

Over: CANOE CREEK

099071908, Winneshiek, IA

Built 2006 Load: 52.7 t ADT: 187

LOCAL

Good

Over: SMALL CREEK

084120801, Benton, IA

Built 1998 Load: 52.8 t ADT: 34

IA 188

Good

Over: HORTON CREEK

0.1 mi. W of Jct. SR V14, Bremer, IA

Built 1987 Load: 52.8 t ADT: 930

130TH ST

Good

Over: DRAINAGE DITCH #3

091210801, Franklin, IA

Built 2012 Load: 52.8 t ADT: 47

ADAIR MADISON AVE

Good

Over: STREAM

076290602, Madison, IA

Built 2015 Load: 52.8 t ADT: 50

F58 LITTLEFIELD DR

Good

Over: CREEK

FM 078340802, Audubon, IA

Built 2005 Load: 52.9 t ADT: 548

MILLER CREEK RD

Good

Over: MILLER CREEK

87-12-04-01-20, Black Hawk, IA

Built 2005 Load: 52.9 t ADT: 49

FOX RD

Good

Over: INDIAN CREEK

88-11-19-03-10, Black Hawk, IA

Built 2004 Load: 52.9 t ADT: 88

GILBERTVILLE RD

Good

Over: INDIAN CREEK

88-12-26-08-10, Black Hawk, IA

Built 2004 Load: 52.9 t ADT: 403

LOCAL

Good

Over: BEAVER CREEK

083280701, Boone, IA

Built 2007 Load: 52.9 t ADT: 15

LOCAL

Good

Over: BEAVER CREEK

083281801, Boone, IA

Built 2004 Load: 52.9 t ADT: 26

WASHINGTON AVE

Good

Over: S FORK MAQUOKETA RIVER

090071404, Buchanan, IA

Built 2005 Load: 52.9 t ADT: 88

LOCAL

Good

Over: S FORK MAQUOKETA RIVER

090072303, Buchanan, IA

Built 1997 Load: 52.9 t ADT: 49

FM

Good

Over: BUFFALO CREEK

090081103, Buchanan, IA

Built 2004 Load: 52.9 t ADT: 432

FM

Good

Over: STREAM

090100702, Buchanan, IA

Built 1999 Load: 52.9 t ADT: 34

FM

Good

Over: RACCOON RIVER

091362301, Buena Vista, IA

Built 1997 Load: 52.9 t ADT: 50

LOCAL

Good

Over: RACOON RIVER

091362601, Buena Vista, IA

Built 2006 Load: 52.9 t ADT: 34

FM

Good

Over: BRANCH LITTLE SIOUX RVR

093381401, Buena Vista, IA

Built 1996 Load: 52.9 t ADT: 45

FM

Good

Over: MC CLURE CREEK

091151703, Butler, IA

Built 1999 Load: 52.9 t ADT: 903

LOCAL

Good

Over: CAMP CREEK

086340505, Calhoun, IA

Built 2006 Load: 52.9 t ADT: 26

LOCAL

Good

Over: LAKE CREEK

086342305, Calhoun, IA

Built 1995 Load: 52.9 t ADT: 50

290TH ST

Good

Over: FIELD STREAM

082351101, Carroll, IA

Built 2000 Load: 52.9 t ADT: 50

RT M68

Good

Over: OVER BNSF RR

082361502, Carroll, IA

Built 1990 Load: 52.9 t ADT: 627

LOCAL

Good

Over: MIDDLE RACCOON RIVER

084352308, Carroll, IA

Built 1991 Load: 52.9 t ADT: 459

JACKSON RD

Good

Over: TURKEY CREEK

076361406, Cass, IA

Built 2008 Load: 52.9 t ADT: 139

FM

Good

Over: SUGAR CREEK

080022504, Cedar, IA

Built 2002 Load: 52.9 t ADT: 70

FM- WASHTA RD

Good

Over: WILLOW CREEK

090413006, Cherokee, IA

Built 2003 Load: 52.9 t ADT: 71

US 30

Good

Over: N. GROVE CREEK

3.1 mi. E of W jct. IA 37, Crawford, IA

Built 1994 Load: 52.9 t ADT: 3,180

FM

Good

Over: W FK W NISHNABOTNA RIVER

083373202, Crawford, IA

Built 2002 Load: 52.9 t ADT: 170

LOCAL

Good

Over: MIDDLE SOLDIER RIVER

084411001, Crawford, IA

Built 2007 Load: 52.9 t ADT: 11

FM

Good

Over: MIDDLE SOLDIER RIVER

084412002, Crawford, IA

Built 2007 Load: 52.9 t ADT: 110

FM

Good

Over: BULGER CREEK

078272903, Dallas, IA

Built 1995 Load: 52.9 t ADT: 150

COUNTY ROAD

Good

Over: MOSQUITO CREEK

079290806, Dallas, IA

Built 2002 Load: 52.9 t ADT: 51

LOCAL

Good

Over: LITTLE SIOUX RIVER

100372101, Dickinson, IA

Built 1999 Load: 52.9 t ADT: 71

IA 93

Good

Over: VOLGA RIVER

0.2 MI. W OF S.R. W14, Fayette, IA

Built 1989 Load: 52.9 t ADT: 790

LOCAL

Good

Over: BEEMIS CREEK

094180802, Floyd, IA

Built 2003 Load: 52.9 t ADT: 29

FM

Good

Over: FLOOD CREEK

095171004, Floyd, IA

Built 2000 Load: 52.9 t ADT: 59

FM

Good

Over: FLOOD CREEK

095171002, Floyd, IA

Built 2001 Load: 52.9 t ADT: 49

FM

Good

Over: FLOOD CREEK

095173501, Floyd, IA

Built 1998 Load: 52.9 t ADT: 79

Showing 16,001-16,050 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.