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: CREEK

096160810, Floyd, IA

Built 1989 Load: 32.7 t ADT: 108

FM

Good

Over: DRAINAGE

096161405, Floyd, IA

Built 1989 Load: 32.7 t ADT: 1,640

FM

Good

Over: STEWART CREEK

096171302, Floyd, IA

Built 2007 Load: 32.7 t ADT: 1,365

LOCAL

Good

Over: SMALL STREAM

096181704, Floyd, IA

Built 1994 Load: 32.7 t ADT: 49

LOCAL

Good

Over: CREEK

097183301, Floyd, IA

Built 2007 Load: 32.7 t ADT: 20

180TH STREET

Good

Over: DD

096173203, Floyd, IA

Built 2008 Load: 32.7 t ADT: 44

260TH

Good

Over: BEEMIS CREEK

094180801, Floyd, IA

Built 2017 Load: 32.7 t ADT: 11

110TH ST

Good

Over: DRY RUN CREEK

097182901, Floyd, IA

Built 1996 Load: 32.7 t ADT: 49

US 18 EB

Good

Over: CPRR

1.0 mi. E of SR T26, Floyd, IA

Built 1998 Load: 32.7 t ADT: 5,050

US 18 WB

Good

Over: CPRR

1.0 mi. E of SR T26, Floyd, IA

Built 1998 Load: 32.7 t ADT: 5,100

80TH STREET

Good

Over: FOCKLER CREEK

090190101, Franklin, IA

Built 1986 Load: 32.7 t ADT: 35

FM 65TH ST

Good

Over: N BEAVER CREEK

090190903, Franklin, IA

Built 2011 Load: 32.7 t ADT: 108

LOCAL 60TH ST

Good

Over: SMALL STREAM

090191601, Franklin, IA

Built 2010 Load: 32.7 t ADT: 26

TIMBER AVE

Good

Over: SMALL STREAM

90192102, Franklin, IA

Built 2020 Load: 32.7 t ADT: 11

S25 HEATHER AVE

Good

Over: DD NO 6

90210502, Franklin, IA

Built 2013 Load: 32.7 t ADT: 697

70TH ST

Good

Over: DD NO. 6

090210801, Franklin, IA

Built 2005 Load: 32.7 t ADT: 570

IRONWOOD AVE

Good

Over: DRAINAGE DITCH NO 6

090210904, Franklin, IA

Built 2012 Load: 32.7 t ADT: 21

OAKLAND DRIVE

Good

Over: DRAINAGE DITCH NO 2

90223605, Franklin, IA

Built 2022 Load: 32.7 t ADT: 11

175TH STREET

Good

Over: SMALL STREAM

092191503, Franklin, IA

Built 1989 Load: 32.7 t ADT: 35

FM SPRUCE AVE

Good

Over: BEEDS CREEK

092193104, Franklin, IA

Built 2004 Load: 32.7 t ADT: 39

FM RAVEN AVE

Good

Over: SMALL STREAM

092201302, Franklin, IA

Built 1989 Load: 32.7 t ADT: 59

RAVEN AVE

Good

Over: BEEDS CREEK

092203601, Franklin, IA

Built 2012 Load: 32.7 t ADT: 41

FM 190TH ST

Good

Over: BUFFALO CREEK

092210901, Franklin, IA

Built 1995 Load: 32.7 t ADT: 884

S33(JONQUILAVE)

Good

Over: BUFFALO CREEK

092211002, Franklin, IA

Built 2011 Load: 32.7 t ADT: 25

FM JONQUIL AVE

Good

Over: SPRING CREEK

092212202, Franklin, IA

Built 1986 Load: 32.7 t ADT: 29

KILLDEER AVE

Good

Over: SPRING CREEK

092212602, Franklin, IA

Built 1983 Load: 32.7 t ADT: 30

160TH STREET

Good

Over: SPRING CREEK

092212701, Franklin, IA

Built 1986 Load: 32.7 t ADT: 47

WRIGHT AVE

Good

Over: FIELD DRAW

092220702, Franklin, IA

Built 1980 Load: 32.7 t ADT: 30

SPRUCE AVE

Good

Over: STREAM

093191904, Franklin, IA

Built 1982 Load: 32.7 t ADT: 11

THRUSH AVE

Good

Over: SMALL STREAM

093192004, Franklin, IA

Built 2017 Load: 32.7 t ADT: 5

230TH STREET

Good

Over: SMALL STREAM

93192101, Franklin, IA

Built 2018 Load: 32.7 t ADT: 11

230TH STREET

Good

Over: BOYLAN CREEK

093192401, Franklin, IA

Built 1984 Load: 32.7 t ADT: 5

THRUSH AVE

Good

Over: SMALL STREAM

93192906, Franklin, IA

Built 2022 Load: 32.7 t ADT: 21

FM 210TH ST

Good

Over: SMALL STREAM

093193203, Franklin, IA

Built 2009 Load: 32.7 t ADT: 39

FM 210TH ST

Good

Over: SMALL STREAM

093193203, Franklin, IA

Built 2009 Load: 32.7 t ADT: 39

FM 210TH ST

Good

Over: DRAINAGE DITCH

093193501, Franklin, IA

Built 1986 Load: 32.7 t ADT: 422

FM RAVEN AVE

Good

Over: SMALL STREAM

093202502, Franklin, IA

Built 1984 Load: 32.7 t ADT: 69

S33 JONQUIL AVE

Good

Over: SMALL STREAM

093212701, Franklin, IA

Built 2012 Load: 32.7 t ADT: 20

MALLARD AVE

Good

Over: BEEDS CREEK

092213601, Franklin, IA

Built 2011 Load: 32.7 t ADT: 35

BALSAM AVE

Good

Over: DD#32

091221702, Franklin, IA

Built 1985 Load: 32.7 t ADT: 35

FM 255TH ST

Good

Over: BOYLAN CREEK

093190303, Franklin, IA

Built 1991 Load: 32.7 t ADT: 658

50TH ST

Good

Over: UNNAMED WATERWAY

090201901, Franklin, IA

Built 2011 Load: 32.7 t ADT: 49

NETTLE AVE

Good

Over: UNNAMED STREAM

92200802, Franklin, IA

Built 2021 Load: 32.7 t ADT: 91

FM J018

Good

Over: BRANCH HUNTER CREEK

070401507, Fremont, IA

Built 1993 Load: 32.7 t ADT: 528

310 STREET

Good

Over: HIGH CREEK

067403001, Fremont, IA

Built 1990 Load: 32.7 t ADT: 358

270 STREET

Good

Over: MILL CREEK

067410401, Fremont, IA

Built 1982 Load: 32.7 t ADT: 11

190 STREET

Good

Over: COOPER CREEK

069422201, Fremont, IA

Built 1998 Load: 32.7 t ADT: 71

200 STREET

Good

Over: COOPER CREEK

069422701, Fremont, IA

Built 1989 Load: 32.7 t ADT: 51

130 STREET

Good

Over: HONEY CREEK

070401901, Fremont, IA

Built 1991 Load: 32.7 t ADT: 15

FM

Good

Over: HONEY CREEK

070413601, Fremont, IA

Built 2003 Load: 32.7 t ADT: 15

Showing 11,501-11,550 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.