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

LOCAL

Good

Over: TWELVE MILE CREEK

086142410, Tama, IA

Built 1989 Load: 45.4 t ADT: 59

FM

Good

Over: INDIAN CREEK

067090304, Van Buren, IA

Built 1996 Load: 45.4 t ADT: 10

FM

Good

Over: BUCKEYE CREEK

072121502, Wapello, IA

Built 2006 Load: 45.4 t ADT: 320

FM

Good

Over: DD

076240404, Warren, IA

Built 1994 Load: 45.4 t ADT: 2,641

FAIRBANKS AVE

Good

Over: LIZARD CREEK

089302401, Webster, IA

Built 2016 Load: 45.4 t ADT: 71

IA 17

Good

Over: DRAINAGE DITCH

2.7 mi. N of S.R. C30, Wright, IA

Built 1987 Load: 45.4 t ADT: 1,360

C26 (150TH ST)

Good

Over: BOONE RIVER

093263101, Wright, IA

Built 2012 Load: 45.4 t ADT: 305

285 ST

Good

Over: MIDDLE NODAWAY RIVER

074320605, Adair, IA

Built 2000 Load: 45.5 t ADT: 26

LOCAL

Good

Over: MARVEL CREEK

075300702, Adair, IA

Built 1997 Load: 45.5 t ADT: 82

FM

Good

Over: MIDDLE NODAWAY RIVER

077333202, Adair, IA

Built 1996 Load: 45.5 t ADT: 29

HICKORY AVENUE

Good

Over: WEST FORK 102 RIVER

071342008, Adams, IA

Built 2004 Load: 45.5 t ADT: 29

LOCAL

Good

Over: PAINT CREEK

097051402, Allamakee, IA

Built 2004 Load: 45.5 t ADT: 60

LOCAL

Good

Over: BRANCH UPPER IOWA RIVER

100042803, Allamakee, IA

Built 2003 Load: 45.5 t ADT: 59

HAMMOND AVE

Good

Over: MILLER CREEK

87-13-26-02-10, Black Hawk, IA

Built 1989 Load: 45.5 t ADT: 49

FM 265TH ST

Good

Over: WATERWAY

091142903, Bremer, IA

Built 2001 Load: 45.5 t ADT: 88

120TH ST

Good

Over: CREEK

093121401, Bremer, IA

Built 2008 Load: 45.5 t ADT: 39

ROBIN AVE

Good

Over: CREEK

082341302, Carroll, IA

Built 2005 Load: 45.5 t ADT: 45

FM

Good

Over: FIELD STREAM

083340202, Carroll, IA

Built 2003 Load: 45.5 t ADT: 29

LOCAL

Good

Over: SPRING BRANCH

083341604, Carroll, IA

Built 1996 Load: 45.5 t ADT: 20

LOCAL

Good

Over: MIDDLE RACCON RIVER

084350602, Carroll, IA

Built 2001 Load: 45.5 t ADT: 50

FM

Good

Over: MIDDLE RACOON RIVER

085362504, Carroll, IA

Built 2002 Load: 45.5 t ADT: 29

300TH ST

Good

Over: MIDDLE BR WAPSINONOC CR

079041501, Cedar, IA

Built 2005 Load: 45.5 t ADT: 92

CEDAR/JOHNSON

Good

Over: WAPSINONOC CREEK

079041904, Cedar, IA

Built 1996 Load: 45.5 t ADT: 20

LOCAL-600TH ST

Good

Over: PITCHER CREEK

090390301, Cherokee, IA

Built 1996 Load: 45.5 t ADT: 11

LOCAL Y AVE

Good

Over: STREAM

093391204, Cherokee, IA

Built 2007 Load: 45.5 t ADT: 26

290TH AVE

Good

Over: DEEP CREEK

000000000, Clinton, IA

Built 2009 Load: 45.5 t ADT: 70

LOCAL

Good

Over: SOLDIER CREEK

100321804, Emmet, IA

Built 1999 Load: 45.5 t ADT: 15

210TH ST

Good

Over: WEST BEAVER CREEK

084293401, Greene, IA

Built 2003 Load: 45.5 t ADT: 46

215 TH

Good

Over: STREAM

084313303, Greene, IA

Built 2005 Load: 45.5 t ADT: 51

E AVE

Good

Over: STREAM

084321404, Greene, IA

Built 2002 Load: 45.5 t ADT: 35

H AVE

Good

Over: STREAM

085311702, Greene, IA

Built 2003 Load: 45.5 t ADT: 41

BEACH ST

Good

Over: BREWERS CREEK

088261204, Hamilton, IA

Built 1995 Load: 45.5 t ADT: 1,745

150TH ST

Good

Over: DD # 159

094250901, Hancock, IA

Built 2000 Load: 45.5 t ADT: 21

1030 GRANT AVE

Good

Over: E BR BOONE RIVER

094253102, Hancock, IA

Built 2007 Load: 45.5 t ADT: 15

950 110TH ST

Good

Over: WEST OTTER CREEK DD 26

094253301, Hancock, IA

Built 1997 Load: 45.5 t ADT: 134

LOCAL

Good

Over: DD

091282302, Humboldt, IA

Built 2002 Load: 45.5 t ADT: 30

LOCAL

Good

Over: BLOODY RUN CREEK

093293402, Humboldt, IA

Built 1998 Load: 45.5 t ADT: 30

LOCAL

Good

Over: STREAM

087402504, Ida, IA

Built 1996 Load: 45.5 t ADT: 41

LOCAL

Good

Over: HALFWAY CREEK

089392402, Ida, IA

Built 1998 Load: 45.5 t ADT: 41

LOCAL

Good

Over: CREEK

089400302, Ida, IA

Built 1996 Load: 45.5 t ADT: 30

LOCAL

Good

Over: SMALL STREAM

080093501, Iowa, IA

Built 2003 Load: 45.5 t ADT: 30

LOC 145TH ST

Good

Over: HINE CREEK

094290703, Kossuth, IA

Built 1999 Load: 45.5 t ADT: 5

LOC 390TH ST

Good

Over: UNION SLOUGH DITCH

098281101, Kossuth, IA

Built 2006 Load: 45.5 t ADT: 35

LOCAL

Good

Over: WEST BRANCH

069062904, Lee, IA

Built 1996 Load: 45.5 t ADT: 40

FM

Good

Over: SMALL STREAM

074190501, Marion, IA

Built 2004 Load: 45.5 t ADT: 100

LOCAL

Good

Over: SNIPE CREEK

082171802, Marshall, IA

Built 2003 Load: 45.5 t ADT: 20

LOCAL

Good

Over: SNIPE CREEK

082191402, Marshall, IA

Built 2004 Load: 45.5 t ADT: 5

LOCAL

Good

Over: DAVISONS CREEK

083172301, Marshall, IA

Built 2005 Load: 45.5 t ADT: 30

FM

Good

Over: LINN CREEK

084203302, Marshall, IA

Built 2007 Load: 45.5 t ADT: 147

FM

Good

Over: CREEK

076041901, Muscatine, IA

Built 2005 Load: 45.5 t ADT: 170

Showing 15,251-15,300 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.