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

IA 5

Good

Over: SOUTH CEDAR CREEK

3.0 MI. S OF S.R. G-71, Marion, IA

Built 1983 Load: 51.2 t ADT: 3,340

LOCAL

Good

Over: OCHEYEDAN RIVER

099402302, Osceola, IA

Built 1992 Load: 51.2 t ADT: 62

IA 173

Good

Over: ELKHORN CREEK

1.1 mi. N of Jct. SR F-58, Shelby, IA

Built 2003 Load: 51.2 t ADT: 1,500

LOCAL

Good

Over: CREEK

083170405, Marshall, IA

Built 2003 Load: 51.3 t ADT: 59

US 169

Good

Over: E FORK DES MOINES RIVER

0.1 mi. S of Jct. US 18, Kossuth, IA

Built 2008 Load: 51.4 t ADT: 7,500

LOCAL

Good

Over: STREAM

100402202, Osceola, IA

Built 1951 Load: 51.4 t ADT: 11

LOCAL

Good

Over: STREAM

100402801, Osceola, IA

Built 1957 Load: 51.4 t ADT: 30

TULIP AVENUE

Good

Over: SAYLINGS CREEK

071321602, Adams, IA

Built 2002 Load: 51.6 t ADT: 40

FM - LEWIS

Good

Over: WATERWAY

075371504, Cass, IA

Built 1998 Load: 51.6 t ADT: 358

175TH ST.

Good

Over: SMALL STREAM

082E20907, Clinton, IA

Built 1992 Load: 51.6 t ADT: 26

120TH ST

Good

Over: DRAINAGE DITCH #3

091211701, Franklin, IA

Built 2012 Load: 51.6 t ADT: 41

LOCAL

Good

Over: STREAM

074180402, Marion, IA

Built 2007 Load: 51.6 t ADT: 21

LOCAL

Good

Over: DRAINAGE

083180903, Marshall, IA

Built 2006 Load: 51.6 t ADT: 340

140TH AVE

Good

Over: DRAINAGE DITCH

083E13502, Clinton, IA

Built 2003 Load: 51.7 t ADT: 550

IA 2

Good

Over: LOTTS CREEK

4.9 mi. E OF E JCT US 169, Ringgold, IA

Built 1985 Load: 51.7 t ADT: 1,750

ACKER RD

Good

Over: TRIB TO ROCK CREEK

87-13-07-02-10, Black Hawk, IA

Built 2006 Load: 51.8 t ADT: 10

IA 4

Good

Over: E BR LAKE CREEK

3.5 mi. N of N jct IA 175, Calhoun, IA

Built 1991 Load: 51.8 t ADT: 1,120

310TH ST

Good

Over: LITTLE ELKHORN CR

079012001, Cedar, IA

Built 2000 Load: 51.8 t ADT: 61

170TH ST

Good

Over: WAPSIPINICON RIVER

098143101, Howard, IA

Built 1988 Load: 51.8 t ADT: 62

COUNTY LINE RD

Good

Over: PRAIRIE CREEK

077200603, Marion, IA

Built 2012 Load: 51.8 t ADT: 26

FM

Good

Over: LITTLE SIOUX RIVER

082442103, Monona, IA

Built 2007 Load: 51.8 t ADT: 100

FM

Good

Over: TURKEY RIVER

099113410, Howard, IA

Built 1995 Load: 51.9 t ADT: 265

FM

Good

Over: BEAVER CREEK

090152906, Butler, IA

Built 1998 Load: 52.2 t ADT: 216

FM

Good

Over: BRUSH CREEK

069243104, Decatur, IA

Built 2004 Load: 52.2 t ADT: 40

LOCAL

Good

Over: EAST GRAND CREEK

080201306, Jasper, IA

Built 1999 Load: 52.2 t ADT: 20

255TH ST

Good

Over: LAKE KEOMAH

0.9 mi.E of SR Queens Ave, Mahaska, IA

Built 2006 Load: 52.2 t

IA 48

Good

Over: MORMAN BRANCH CREEK

3.8 MI. S OF U.S. 34, Montgomery, IA

Built 1987 Load: 52.2 t ADT: 2,000

135TH ST

Good

Over: JACKSON CREEK

069213002, Wayne, IA

Built 2017 Load: 52.2 t ADT: 80

330TH ST

Good

Over: STREAM

0.6 mi W of Hwy 25 on 330, Adair, IA

Built 2023 Load: 52.5 t ADT: 26

SHELDON AVE

Good

Over: NORTH RIVER

.4 mi N of G15 on Sheldon, Adair, IA

Built 2020 Load: 52.5 t ADT: 21

RIVERSIDE AVE

Good

Over: NORTH RIVER

Riverside 0.8 mi N of G15, Adair, IA

Built 2023 Load: 52.5 t ADT: 62

IA 24

Good

Over: PLUM CREEK

4.0 MI. E OF S.R. B57, Chickasaw, IA

Built 2000 Load: 52.5 t ADT: 4,290

167TH ST

Good

Over: CREEK

85N3E127387, Jackson, IA

Built 2015 Load: 52.5 t ADT: 34

M37 BOXELDER AVE

Good

Over: CRABAPPLE CREEK

072391604, Montgomery, IA

Built 2021 Load: 52.5 t ADT: 100

LOCAL

Good

Over: PAINT CREEK

097041807, Allamakee, IA

Built 1992 Load: 52.6 t ADT: 97

FM

Good

Over: PAINT CREEK

097051207, Allamakee, IA

Built 1990 Load: 52.6 t ADT: 69

LOCAL

Good

Over: SHOAL CREEK

068183604, Appanoose, IA

Built 1995 Load: 52.6 t ADT: 113

FM

Good

Over: WALNUT CREEK

069192708, Appanoose, IA

Built 2002 Load: 52.6 t ADT: 90

LOCAL

Good

Over: BAILEYE CREEK

093210101, Cerro Gordo, IA

Built 1991 Load: 52.6 t ADT: 51

HARVARD TRAIL

Good

Over: ALLEN CREEK

080433006, Harrison, IA

Built 2008 Load: 52.6 t ADT: 34

LOCAL

Good

Over: DD #3

091271403, Humboldt, IA

Built 1989 Load: 52.6 t ADT: 40

NB US 218

Good

Over: CROOKED CREEK

2.3 mi. S of SR F62., Johnson, IA

Built 1982 Load: 52.6 t ADT: 9,650

LOC 60TH AVE

Good

Over: BLACK CAT CREEK

097303602, Kossuth, IA

Built 1998 Load: 52.6 t ADT: 11

LOC 80TH AVE

Good

Over: E FORK DES MOINES RIVER

098292002, Kossuth, IA

Built 1988 Load: 52.6 t ADT: 60

LOC 60TH AVE

Good

Over: E FORK DES MOINES RIVER

098301302, Kossuth, IA

Built 1989 Load: 52.6 t ADT: 50

LOCAL

Good

Over: FLOYD RIVER

097421202, O'Brien, IA

Built 1995 Load: 52.6 t ADT: 21

F AVENUE

Good

Over: STREAM

070383102, Page, IA

Built 1987 Load: 52.6 t ADT: 40

D AVENUE

Good

Over: STREAM

070393504, Page, IA

Built 2007 Load: 52.6 t ADT: 60

210TH STREET

Good

Over: FOURMILE CREEK

072283505, Union, IA

Built 1995 Load: 52.6 t ADT: 50

LOCAL

Good

Over: STREAM

070102202, Van Buren, IA

Built 2007 Load: 52.6 t ADT: 26

Showing 15,901-15,950 of 20,753 bridges

Related

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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.