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

230 STREET

Good

Over: SMALL STREAM

068401701, Fremont, IA

Built 1983 Load: 32.7 t ADT: 60

J-18

Good

Over: PLUM CREEK

070421710, Fremont, IA

Built 2008 Load: 32.7 t ADT: 289

W AVE

Good

Over: SNAKE CREEK

082292302, Greene, IA

Built 1983 Load: 32.7 t ADT: 35

W AVE

Good

Over: SNAKE CREEK

082292302, Greene, IA

Built 1984 Load: 32.7 t ADT: 35

190 TH

Good

Over: HARDIN CREEK

084302001, Greene, IA

Built 1983 Load: 32.7 t ADT: 50

FM

Good

Over: BRANCH OF LITTLE WOLF CR

086171202, Grundy, IA

Built 1987 Load: 32.7 t ADT: 29

KING AVE

Good

Over: BRANCH WOLF CREEK

086173408, Grundy, IA

Built 2000 Load: 32.7 t ADT: 11

LOCAL

Good

Over: DOWD CREEK

086180401, Grundy, IA

Built 1990 Load: 32.7 t ADT: 39

LOCAL

Good

Over: BLACK HAWK CREEK

087153501, Grundy, IA

Built 1986 Load: 32.7 t ADT: 59

LOCAL

Good

Over: BLACKHAWK CREEK ,BRANCH

087180302, Grundy, IA

Built 1977 Load: 32.7 t ADT: 70

LOCAL

Good

Over: BRANCH OF BLACKHAWK CRK

088151001, Grundy, IA

Built 1987 Load: 32.7 t ADT: 11

175TH ST

Good

Over: BRANCH BLACK HAWK CREEK

088151203, Grundy, IA

Built 2015 Load: 32.7 t ADT: 70

FM

Good

Over: BLACKHAWK CREEK ,BRANCH

088152202, Grundy, IA

Built 1989 Load: 32.7 t ADT: 20

LOCAL

Good

Over: BLACKHAWK CREEK

088161001, Grundy, IA

Built 1995 Load: 32.7 t ADT: 44

FM

Good

Over: BR.BLACKHAWK CREEK

088162201, Grundy, IA

Built 1986 Load: 32.7 t ADT: 255

LOCAL

Good

Over: FORK OF BLACKHAWK CREEK

088171202, Grundy, IA

Built 1984 Load: 32.7 t ADT: 26

LOCAL RD

Good

Over: BR BLACK HAWK CREEK

088173302, Grundy, IA

Built 2002 Load: 32.7 t ADT: 49

LOCAL

Good

Over: BRANCH BEAVER CREEK

088180903, Grundy, IA

Built 1992 Load: 32.7 t ADT: 39

LOCAL ROAD

Good

Over: BRANCH BEAVER CREEK

089160101, Grundy, IA

Built 1991 Load: 32.7 t ADT: 70

LOCAL

Good

Over: BRANCH OF BEAVER CREEK

089160701, Grundy, IA

Built 1991 Load: 32.7 t ADT: 26

LOCAL

Good

Over: FORK OF BEAVER CREEK

089160901, Grundy, IA

Built 1985 Load: 32.7 t ADT: 39

LOCAL

Good

Over: BRANCH BLACKHAWK CREEK

089162202, Grundy, IA

Built 1991 Load: 32.7 t ADT: 15

FM

Good

Over: BLACKHAWK CREEK BRANCH

089162602, Grundy, IA

Built 1996 Load: 32.7 t ADT: 226

LOCAL

Good

Over: BRANCH OF BLACKHAWK CK

089162701, Grundy, IA

Built 1987 Load: 32.7 t ADT: 26

LOCAL

Good

Over: CREEK

089170601, Grundy, IA

Built 2003 Load: 32.7 t ADT: 33

LOCAL

Good

Over: BR BEAVER CREEK

089181801, Grundy, IA

Built 1996 Load: 32.7 t ADT: 97

A AVE

Good

Over: BRANCH BEAVER CREEK

089181802, Grundy, IA

Built 2012 Load: 32.7 t ADT: 15

FM

Good

Over: FORK WOLF CREEK

086173405, Grundy, IA

Built 1983 Load: 32.7 t ADT: 246

E AVE

Good

Over: SOUTH FORK BEAVER CREEK

088181502, Grundy, IA

Built 2012 Load: 32.7 t ADT: 49

260TH ST

Good

Over: DOWD CREEK

87182801, Grundy, IA

Built 2013 Load: 32.7 t ADT: 20

C AVE

Good

Over: STREAM

088182902, Grundy, IA

Built 2014 Load: 32.7 t ADT: 5

T13 D AVE

Good

Over: WATERWAY

089181002, Grundy, IA

Built 2015 Load: 32.7 t ADT: 805

250TH ST

Good

Over: BLACK HAWK CREEK

087152401, Grundy, IA

Built 2016 Load: 32.7 t ADT: 29

K AVE

Good

Over: BLACK HAWK CREEK

088171002, Grundy, IA

Built 2016 Load: 32.7 t ADT: 39

H AVE

Good

Over: WOLF CREEK

087171902, Grundy, IA

Built 2018 Load: 32.7 t ADT: 44

230TH ST

Good

Over: TRIB OF BLACK HAWK CK

087150801, Grundy, IA

Built 2018 Load: 32.7 t ADT: 11

120TH ST

Good

Over: MIDDLE FORK BEAVER CREEK

089181701, Grundy, IA

Built 2019 Load: 32.7 t ADT: 20

B AVE

Good

Over: CEDAR CREEK

087180702, Grundy, IA

Built 2020 Load: 32.7 t ADT: 39

I AVE

Good

Over: BLACK HAWK CREEK

088172002, Grundy, IA

Built 2021 Load: 32.7 t ADT: 49

L AVE

Good

Over: BLACK HAWK CREEK

088171102, Grundy, IA

Built 2022 Load: 32.7 t ADT: 33

LUITJENS LANE

Good

Over: FORK OF BLACKHAWK CREEK

088150501, Grundy, IA

Built 1999 Load: 32.7 t ADT: 27

FM

Good

Over: SMALL STREAM

088160302, Grundy, IA

Built 1999 Load: 32.7 t ADT: 69

165TH STREET

Good

Over: BR BEAVER CREEK

088180205, Grundy, IA

Built 2003 Load: 32.7 t ADT: 59

T-19

Good

Over: DRAINAGE

088180212, Grundy, IA

Built 2003 Load: 32.7 t ADT: 2,082

FM

Good

Over: DEER CREEK

078302104, Guthrie, IA

Built 1992 Load: 32.7 t ADT: 757

UNION AVE

Good

Over: STREAM

078331902, Guthrie, IA

Built 1995 Load: 32.7 t ADT: 20

LOCAL

Good

Over: TROUBLESOME CREEK

079331701, Guthrie, IA

Built 1988 Load: 32.7 t ADT: 26

100TH ST

Good

Over: STREAM

081310301, Guthrie, IA

Built 2000 Load: 32.7 t ADT: 29

LOCAL

Good

Over: M.RACCOON RIVER

081322903, Guthrie, IA

Built 1989 Load: 32.7 t ADT: 26

170TH STREET

Good

Over: STREAM

080320901, Guthrie, IA

Built 2004 Load: 32.7 t ADT: 20

Showing 11,551-11,600 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.