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: GRANTS CREEK

000000000, Lee, IA

Built 2009 Load: 32.7 t ADT: 60

240TH AVE

Good

Over: CREEK

067050902, Lee, IA

Built 2004 Load: 32.7 t ADT: 60

FM

Good

Over: CREEK

067072009, Lee, IA

Built 1992 Load: 32.7 t ADT: 200

LOCAL SECONDARY

Good

Over: LITTLE SUGAR CREEK

068062504, Lee, IA

Built 2005 Load: 32.7 t ADT: 50

FM

Good

Over: CREEK

068070302, Lee, IA

Built 2005 Load: 32.7 t ADT: 35

LOCAL

Good

Over: LITTLE SUGAR CREEK

068072101, Lee, IA

Built 2004 Load: 32.7 t ADT: 30

FM

Good

Over: SUGAR CREEK LITTLE

068072209, Lee, IA

Built 1994 Load: 32.7 t ADT: 150

FM

Good

Over: LICK CREEK

068073201, Lee, IA

Built 1991 Load: 32.7 t ADT: 90

FM

Good

Over: DEED'S CREEK

069040805, Lee, IA

Built 1986 Load: 32.7 t ADT: 60

LOCAL ROAD

Good

Over: CREEK

069042505, Lee, IA

Built 1997 Load: 32.7 t ADT: 131

LOCAL

Good

Over: UNNAMED STREAM

069043002, Lee, IA

Built 2007 Load: 32.7 t ADT: 100

110TH ST

Good

Over: SUGAR CREEK

069060703, Lee, IA

Built 2007 Load: 32.7 t ADT: 40

LOCAL

Good

Over: CREEK

069062304, Lee, IA

Built 1994 Load: 32.7 t ADT: 80

FM

Good

Over: SUGAR CREEK

069072702, Lee, IA

Built 2002 Load: 32.7 t ADT: 25

FM

Good

Over: SMALL

065051210, Lee, IA

Built 1989 Load: 32.7 t ADT: 680

FM

Good

Over: SMALL STREAM

069061902, Lee, IA

Built 1990 Load: 32.7 t ADT: 590

172ND AVE

Good

Over: CREEK

069060502, Lee, IA

Built 2015 Load: 32.7 t ADT: 15

E.ROBINS RD

Good

Over: CHRISTOPHER CREEK

084072600, Linn, IA

Built 1985 Load: 32.7 t ADT: 5,794

COGGON RD

Good

Over: TRIB. TO WAPSI RIVER

086070305, Linn, IA

Built 1974 Load: 32.7 t ADT: 992

50TH STREET

Good

Over: WANATEE CREEK

084063300, Linn, IA

Built 1998 Load: 32.7 t ADT: 201

HUNTINGTON HILL RD

Good

Over: BERRY'S RUN

084061900, Linn, IA

Built 2002 Load: 32.7 t ADT: 128

29TH AVE

Good

Over: WANATEE CREEK

084063501, Linn, IA

Built 2011 Load: 32.7 t ADT: 6,593

2ND STREET

Good

Over: MONKEY CREEK

075041901, Louisa, IA

Built 1995 Load: 32.7 t ADT: 2,140

LOCAL

Good

Over: SMALL STREAM

073033205, Louisa, IA

Built 2009 Load: 32.7 t ADT: 26

FM

Good

Over: STREAM

073040702, Louisa, IA

Built 1997 Load: 32.7 t ADT: 60

FM

Good

Over: STREAM

073041804, Louisa, IA

Built 1992 Load: 32.7 t ADT: 70

LOCAL

Good

Over: SMALL STREAM

074031505, Louisa, IA

Built 2007 Load: 32.7 t ADT: 135

FM

Good

Over: SMALL STREAM

074032603, Louisa, IA

Built 1989 Load: 32.7 t ADT: 280

W AVENUE

Good

Over: BUFFINGTON CREEK

074052108, Louisa, IA

Built 2022 Load: 32.7 t ADT: 82

COUNTY LINE RD

Good

Over: SM STREAM

074053104, Louisa, IA

Built 1989 Load: 32.7 t ADT: 40

LOCAL

Good

Over: MICHAEL CREEK

075032603, Louisa, IA

Built 1976 Load: 32.7 t ADT: 166

LOCAL

Good

Over: INDIAN CREEK

075041201, Louisa, IA

Built 1987 Load: 32.7 t ADT: 41

LOCAL

Good

Over: SHORT CREEK

075050402, Louisa, IA

Built 2003 Load: 32.7 t ADT: 16

LOCAL

Good

Over: SMALL STREAM

075052104, Louisa, IA

Built 1998 Load: 32.7 t ADT: 11

X 17

Good

Over: MONKEY CREEK & IMRL RR

075052304, Louisa, IA

Built 2008 Load: 32.7 t ADT: 540

FM

Good

Over: CONE MARSH

076051403, Louisa, IA

Built 1985 Load: 32.7 t ADT: 70

FM

Good

Over: SMALL STREAM

075052504, Louisa, IA

Built 1991 Load: 32.7 t ADT: 1,470

H 16 (40TH ST)

Good

Over: SMALL STREAM

073032201, Louisa, IA

Built 2002 Load: 32.7 t ADT: 480

95TH ST

Good

Over: BURLINGTON CREEK

074052103, Louisa, IA

Built 2020 Load: 32.7 t ADT: 35

FM

Good

Over: CEDAR CREEK

071200105, Lucas, IA

Built 2000 Load: 32.7 t ADT: 40

FM

Good

Over: BRANCH OF CEDAR CREEK

071200105, Lucas, IA

Built 2000 Load: 32.7 t ADT: 40

LOCAL

Good

Over: BR CARRUTHERS CREEK

073200907, Lucas, IA

Built 1978 Load: 32.7 t ADT: 26

310TH AVE

Good

Over: DR TO CARRUTHERS CREEK

073201502, Lucas, IA

Built 2013 Load: 32.7 t ADT: 26

310TH AVE

Good

Over: BR OF NORTH CEDAR CREEK

073202704, Lucas, IA

Built 2017 Load: 32.7 t ADT: 11

LOCAL

Good

Over: BR LITTLE WHITEBREAST CK

073211904, Lucas, IA

Built 2007 Load: 32.7 t ADT: 47

LOCAL

Good

Over: BR NORTH CEDAR RIVER

073203304, Lucas, IA

Built 2003 Load: 32.7 t ADT: 5

LOCAL

Good

Over: DR. TO WHITEBREAST CREEK

072232804, Lucas, IA

Built 2007 Load: 32.7 t ADT: 11

LOCAL

Good

Over: DR TO LITTLE WHITEBREAST

073211904, Lucas, IA

Built 2007 Load: 32.7 t ADT: 47

LOCAL

Good

Over: BRANCH OF BRUSH CREEK

072232102, Lucas, IA

Built 2008 Load: 32.7 t ADT: 62

FM

Good

Over: WEST RAT CREEK

098430101, Lyon, IA

Built 2007 Load: 32.7 t ADT: 578

Showing 11,801-11,850 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.