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

FM

Good

Over: FORK BEAVER CREEK

089182702, Grundy, IA

Built 2004 Load: 52.9 t ADT: 108

LOCAL

Good

Over: WHITE FOX CREEK

089252803, Hamilton, IA

Built 1994 Load: 52.9 t ADT: 34

1780 200TH ST

Good

Over: EAST IOWA RIVER

095241405, Hancock, IA

Built 2007 Load: 52.9 t ADT: 399

LOCAL

Good

Over: CREEK

086213402, Hardin, IA

Built 2006 Load: 52.9 t ADT: 25

LOCAL

Good

Over: BEAVER CREEK

087201303, Hardin, IA

Built 2003 Load: 52.9 t ADT: 51

L AVE

Good

Over: TIPTON CREEK

087212206, Hardin, IA

Built 2007 Load: 52.9 t ADT: 5

FM

Good

Over: IA RIVER

088212704, Hardin, IA

Built 2001 Load: 52.9 t ADT: 34

FM

Good

Over: DRAINAGE DITCH

088220601, Hardin, IA

Built 2005 Load: 52.9 t ADT: 177

LOCAL

Good

Over: IOWA RIVER

088221303, Hardin, IA

Built 1995 Load: 52.9 t ADT: 39

LOCAL

Good

Over: MUD CREEK

072072705, Henry, IA

Built 2004 Load: 52.9 t ADT: 73

FM

Good

Over: PRARIE CREEK

093270401, Humboldt, IA

Built 2003 Load: 52.9 t ADT: 290

FM

Good

Over: LOTTS CREEK

093290402, Humboldt, IA

Built 1996 Load: 52.9 t ADT: 350

HARDSCRABBLE RD

Good

Over: DEER CREEK

086031708, Jones, IA

Built 2007 Load: 52.9 t ADT: 540

FM 190TH AVE

Good

Over: PRAIRIE CREEK

094271902, Kossuth, IA

Built 2002 Load: 52.9 t ADT: 489

FM 40TH AVE

Good

Over: LOTTS CREEK

094301502, Kossuth, IA

Built 2004 Load: 52.9 t ADT: 230

FM 130TH ST

Good

Over: LOTTS CREEK

094302201, Kossuth, IA

Built 2001 Load: 52.9 t ADT: 569

FM 150TH AVE

Good

Over: PLUM CREEK

096281602, Kossuth, IA

Built 1997 Load: 52.9 t ADT: 369

FM 360TH ST

Good

Over: NORTH BUFFALO CREEK

098272601, Kossuth, IA

Built 1994 Load: 52.9 t ADT: 450

FM 40TH AVE

Good

Over: E FORK DES MOINES RIVER

098301001, Kossuth, IA

Built 2006 Load: 52.9 t ADT: 190

LAFAYETTE RD

Good

Over: WEST OTTER CREEK

085082503, Linn, IA

Built 2007 Load: 52.9 t ADT: 246

44TH STREET

Good

Over: WANATEE CREEK

084063200, Linn, IA

Built 2001 Load: 52.9 t ADT: 5,894

FM

Good

Over: SMALL STREAM

073031502, Louisa, IA

Built 1990 Load: 52.9 t ADT: 80

FM

Good

Over: CEDAR CREEK

074143402, Mahaska, IA

Built 1991 Load: 52.9 t ADT: 20

LOCAL

Good

Over: LITTLE MUCHAKINOCK CREEK

075162606, Mahaska, IA

Built 1988 Load: 52.9 t ADT: 210

FM

Good

Over: MUCHAKINOCK CREEK

075163410, Mahaska, IA

Built 2007 Load: 52.9 t ADT: 90

FM

Good

Over: BRUSH CREEK

082170805, Marshall, IA

Built 2002 Load: 52.9 t ADT: 511

FM

Good

Over: MINERVA CREEK

084201102, Marshall, IA

Built 2001 Load: 52.9 t ADT: 501

LOCAL(WHITING)

Good

Over: MCCANDLESS CLEGHORN

084460201, Monona, IA

Built 1997 Load: 52.9 t ADT: 763

188TH TRL

Good

Over: COAL CREEK

072171803, Monroe, IA

Built 2000 Load: 52.9 t ADT: 45

FM

Good

Over: TARKIO CREEK

073372202, Montgomery, IA

Built 1994 Load: 52.9 t ADT: 270

LOCAL

Good

Over: PIKE RUN

077031701, Muscatine, IA

Built 2004 Load: 52.9 t ADT: 91

N AVENUE

Good

Over: WEST MILL CREEK

067370504, Page, IA

Built 2001 Load: 52.9 t ADT: 289

C70

Good

Over: MUD CREEK

090443101, Plymouth, IA

Built 1999 Load: 52.9 t ADT: 450

280TH ST

Good

Over: PERRY CREEK

090470201, Plymouth, IA

Built 2005 Load: 52.9 t ADT: 11

325TH ST

Good

Over: PERRY CREEK

090472705, Plymouth, IA

Built 2006 Load: 52.9 t ADT: 319

FM

Good

Over: LITTLE SIOUX

091432301, Plymouth, IA

Built 1991 Load: 52.9 t ADT: 139

220TH ST

Good

Over: PLYMOUTH CREEK

091450301, Plymouth, IA

Built 2004 Load: 52.9 t ADT: 15

FM

Good

Over: WHISKEY CREEK

092433501, Plymouth, IA

Built 1997 Load: 52.9 t ADT: 848

160TH ST

Good

Over: MINK CREEK

092460301, Plymouth, IA

Built 2003 Load: 52.9 t ADT: 26

FM

Good

Over: WESTFIELD CREEK

092481702, Plymouth, IA

Built 1988 Load: 52.9 t ADT: 180

140TH ST

Good

Over: DEEP CREEK

093432801, Plymouth, IA

Built 2001 Load: 52.9 t ADT: 30

150TH ST

Good

Over: DEEP CREEK

093433201, Plymouth, IA

Built 2004 Load: 52.9 t ADT: 60

140TH ST

Good

Over: WILLOW CREEK

093442901, Plymouth, IA

Built 2000 Load: 52.9 t ADT: 20

150TH ST

Good

Over: WILLOW CREEK

093443101, Plymouth, IA

Built 1992 Load: 52.9 t ADT: 71

LOCAL

Good

Over: LIZARD CREEK

090311303, Pocahontas, IA

Built 2004 Load: 52.9 t ADT: 26

FM

Good

Over: S LIZARD CK DD #22

090322501, Pocahontas, IA

Built 2000 Load: 52.9 t ADT: 379

FM

Good

Over: WALNUT CREEK

081141602, Poweshiek, IA

Built 2000 Load: 52.9 t ADT: 60

FM

Good

Over: BIG BEAR CREEK

081162001, Poweshiek, IA

Built 2002 Load: 52.9 t ADT: 340

LOCAL

Good

Over: W FK GRAND RIVER

068300201, Ringgold, IA

Built 2005 Load: 52.9 t ADT: 11

FM

Good

Over: CEDAR CREEK

088351004, Sac, IA

Built 2006 Load: 52.9 t ADT: 50

Showing 16,051-16,100 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.