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

LOC 310TH AVE

Good

Over: BEAR CREEK

090033402, Delaware, IA

Built 2007 Load: 32.7 t ADT: 207

FM 150 ST

Good

Over: SMALL CREEK

090053101, Delaware, IA

Built 1986 Load: 32.7 t ADT: 589

220TH AVENUE

Good

Over: SMALL STREAM

087040602, Delaware, IA

Built 2003 Load: 32.7 t ADT: 49

240TH ST

Good

Over: STREAM

088061401, Delaware, IA

Built 2021 Load: 32.7 t ADT: 90

300TH AVE

Good

Over: STREAM

088031601, Delaware, IA

Built 2021 Load: 32.7 t ADT: 40

W MARION ST

Good

Over: UNNAMED STREAM

089053105, Delaware, IA

Built 2011 Load: 32.7 t ADT: 2,887

LOCAL

Good

Over: SPRING CREEK

069032307, Des Moines, IA

Built 1995 Load: 32.7 t ADT: 51

FM WALKER RD

Good

Over: TURKEY HOLLOW CREEK

070021706, Des Moines, IA

Built 1998 Load: 32.7 t ADT: 60

LOC Y CAMP RD

Good

Over: TURKEY HOLLOW CREEK

070021704, Des Moines, IA

Built 1998 Load: 32.7 t ADT: 104

FM

Good

Over: LITTLE FLINT CREEK

070031706, Des Moines, IA

Built 1998 Load: 32.7 t ADT: 160

220TH AVE

Good

Over: SMALL STREAM

070042904, Des Moines, IA

Built 2011 Load: 32.7 t ADT: 50

HWY 79

Good

Over: LONG CREEK

070043401, Des Moines, IA

Built 1988 Load: 32.7 t ADT: 1,650

FM

Good

Over: COTTONWOOD DRAIN

071010703, Des Moines, IA

Built 2001 Load: 32.7 t ADT: 80

160TH ST

Good

Over: RUNNING SLOUGH DRAIN

071013103, Des Moines, IA

Built 2013 Load: 32.7 t ADT: 11

LOCAL

Good

Over: SMALL STREAM

071023503, Des Moines, IA

Built 2004 Load: 32.7 t ADT: 51

LOCAL

Good

Over: STREAM

071033305, Des Moines, IA

Built 1900 Load: 32.7 t ADT: 91

FM

Good

Over: FLINT RIVER

071041702, Des Moines, IA

Built 2004 Load: 32.7 t ADT: 50

190TH AVE

Good

Over: SMALL STREAM

071042603, Des Moines, IA

Built 2011 Load: 32.7 t ADT: 26

155TH AVE

Good

Over: CEDAR FORK

072032006, Des Moines, IA

Built 2003 Load: 32.7 t ADT: 41

LOCAL

Good

Over: EAST FORK CROOKED RIVER

072040404, Des Moines, IA

Built 2004 Load: 32.7 t ADT: 460

260TH ST

Good

Over: CROOKED CREEK

07204801, Des Moines, IA

Built 2011 Load: 32.7 t ADT: 360

LOCAL

Good

Over: SMALL STREAM

072042002, Des Moines, IA

Built 2001 Load: 32.7 t ADT: 30

LOCAL

Good

Over: CEDAR FORK

072042704, Des Moines, IA

Built 2000 Load: 32.7 t ADT: 30

LOCAL

Good

Over: BIG CREEK

072042902, Des Moines, IA

Built 2001 Load: 32.7 t ADT: 51

190TH ST

Good

Over: STREAM

071031601, Des Moines, IA

Built 2013 Load: 32.7 t ADT: 123

US 61

Good

Over: BRUSH CREEK

0.5 Mi. S of SR X62, Des Moines, IA

Built 1995 Load: 32.7 t ADT: 10,200

PLANT RD Q

Good

Over: LONG CREEK

1500 FT N OF LINE 3A RD, Des Moines, IA

Built 2019 Load: 32.7 t ADT: 5

PLANT ROAD H

Good

Over: BRUSH CREEK

SW OF SEWAGE DISPOSAL PL, Des Moines, IA

Built 2019 Load: 32.7 t ADT: 20

PLANT ROAD K

Good

Over: BRUSH CREEK

APPROX. 5680' E. OF RD. H, Des Moines, IA

Built 2016 Load: 32.7 t ADT: 10

PLANT ROAD I

Good

Over: LONG CREEK

APPROX. 1000' SW OF RD M, Des Moines, IA

Built 2003 Load: 32.7 t ADT: 15

FM

Good

Over: CREEK

098352301, Dickinson, IA

Built 2008 Load: 32.7 t ADT: 447

LOCAL

Good

Over: CREEK

098353401, Dickinson, IA

Built 1999 Load: 32.7 t ADT: 11

LOCAL

Good

Over: STONY CREEK

098380602, Dickinson, IA

Built 1999 Load: 32.7 t ADT: 60

FM

Good

Over: STONY CREEK

098380703, Dickinson, IA

Built 2001 Load: 32.7 t ADT: 934

LOCAL

Good

Over: DRAINAGE

098381702, Dickinson, IA

Built 1992 Load: 32.7 t ADT: 26

LOCAL

Good

Over: MUDDY CREEK

099351001, Dickinson, IA

Built 2007 Load: 32.7 t ADT: 11

FM

Good

Over: MUDDY CREEK

099351501, Dickinson, IA

Built 1999 Load: 32.7 t ADT: 873

LOCAL

Good

Over: MILL POND CREEK

098360707, Dickinson, IA

Built 2008 Load: 32.7 t ADT: 254

140TH AVE

Good

Over: DUGOUT CREEK

099381402, Dickinson, IA

Built 2011 Load: 32.7 t ADT: 20

MINI WAKAN ST PK

Good

Over: SPIRIT LAKE

100360904, Dickinson, IA

Built 1995 Load: 32.7 t

LOCAL

Good

Over: WHITE WATER CREEK

087E10603, Dubuque, IA

Built 2006 Load: 32.7 t ADT: 71

FM

Good

Over: LYTLE CREEK

087E13608, Dubuque, IA

Built 1994 Load: 32.7 t ADT: 370

TARA LANE

Good

Over: STREAM

087011005, Dubuque, IA

Built 2021 Load: 32.7 t ADT: 20

TYLER ST NE

Good

Over: CREEK

000000000, Dubuque, IA

Built 2005 Load: 32.7 t ADT: 509

LOCAL

Good

Over: WHITE WATER CREEK

087013604, Dubuque, IA

Built 1999 Load: 32.7 t ADT: 71

LOCAL

Good

Over: CREEK

087021903, Dubuque, IA

Built 2006 Load: 32.7 t ADT: 50

CHESTERMAN RD

Good

Over: UNNAMED STREAM

088E10303, Dubuque, IA

Built 2022 Load: 32.7 t ADT: 45

FM

Good

Over: CREEK

088E13504, Dubuque, IA

Built 1990 Load: 32.7 t ADT: 1,880

ELMWOOD DR

Good

Over: GRANGER CREEK

00000, Dubuque, IA

Built 2009 Load: 32.7 t ADT: 770

CALONDER RD

Good

Over: CREEK

089E10503, Dubuque, IA

Built 1995 Load: 32.7 t ADT: 157

Showing 11,401-11,450 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.