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: SKILLET CREEK

086271703, Webster, IA

Built 1994 Load: 45.3 t ADT: 50

RACINE AVE

Good

Over: CROOKED CREEK

087281302, Webster, IA

Built 2000 Load: 45.3 t ADT: 41

LOCAL ROAD

Good

Over: BRANCH IOWA RIVER

092233303, Wright, IA

Built 2006 Load: 45.3 t ADT: 42

FM

Good

Over: SMALL STREAM

070160203, Appanoose, IA

Built 2001 Load: 45.4 t ADT: 40

FM (LWC)

Good

Over: SMALL STREAM

082122905, Benton, IA

Built 1993 Load: 45.4 t ADT: 410

JESUP RD

Good

Over: TRIB TO SPRING CREEK

87-11-11-06-10, Black Hawk, IA

Built 2007 Load: 45.4 t ADT: 314

E EAGLE RD

Good

Over: MUD CREEK

87-12-21-01-10, Black Hawk, IA

Built 2004 Load: 45.4 t ADT: 275

HESS RD

Good

Over: TRIB TO MILLER CREEK

87-13-12-02-10, Black Hawk, IA

Built 2005 Load: 45.4 t ADT: 29

YOUNG RD

Good

Over: SPRING CREEK

88-11-12-01-10, Black Hawk, IA

Built 2006 Load: 45.4 t ADT: 393

GIRSCH RD

Good

Over: TRIB TO MILLER CREEK

88-12-34-02-10, Black Hawk, IA

Built 2003 Load: 45.4 t ADT: 128

BARCLAY RD

Good

Over: CAMP CREEK

89-11-13-05-10, Black Hawk, IA

Built 2006 Load: 45.4 t ADT: 88

E CEDAR-WAPSI RD

Good

Over: TRIB TO CRANE CREEK

90-12-13-01-10, Black Hawk, IA

Built 2007 Load: 45.4 t ADT: 1,895

N ELK RUN RD

Good

Over: TRIB TO CRANE CREEK

90-12-15-02-10, Black Hawk, IA

Built 2005 Load: 45.4 t ADT: 79

220TH ST

Good

Over: STREAM

091130503, Bremer, IA

Built 2011 Load: 45.4 t ADT: 70

160TH ST

Good

Over: STREAM

092130101, Bremer, IA

Built 2006 Load: 45.4 t ADT: 108

OVERLAND AVE

Good

Over: SAND CREEK

087082102, Buchanan, IA

Built 1995 Load: 45.4 t ADT: 20

FM 250TH ST

Good

Over: LIME CREEK

088102301, Buchanan, IA

Built 1989 Load: 45.4 t ADT: 69

LOCAL

Good

Over: SMALL STREAM

089100703, Buchanan, IA

Built 1995 Load: 45.4 t ADT: 33

QUONSET AVE

Good

Over: BUFFALO CREEK

090081404, Buchanan, IA

Built 2000 Load: 45.4 t ADT: 29

FM 155TH ST.

Good

Over: SMALL STREAM

090083203, Buchanan, IA

Built 2004 Load: 45.4 t ADT: 344

LOCAL

Good

Over: BR RACCOON RIVER

091360403, Buena Vista, IA

Built 2005 Load: 45.4 t ADT: 45

FM

Good

Over: BRANCH RACCOON RIVER

091361502, Buena Vista, IA

Built 1998 Load: 45.4 t ADT: 450

LOCAL

Good

Over: BR LITTLE SIOUX RIVER

093383602, Buena Vista, IA

Built 2001 Load: 45.4 t ADT: 5

FM

Good

Over: SMALL STREAM

090172706, Butler, IA

Built 2003 Load: 45.4 t ADT: 393

C23

Good

Over: SMALL STREAM

093173401, Butler, IA

Built 2002 Load: 45.4 t ADT: 511

FM

Good

Over: SMALL STREAM

093183401, Butler, IA

Built 1999 Load: 45.4 t ADT: 540

FOREST AVE

Good

Over: SMALL STREAM

Forest Ave. N. of C33, Butler, IA

Built 2020 Load: 45.4 t ADT: 41

120TH ST

Good

Over: SMALL STREAM

670' east of Ridge Ave., Butler, IA

Built 2022 Load: 45.4 t ADT: 35

FM

Good

Over: DD NO. 12

088312202, Calhoun, IA

Built 1990 Load: 45.4 t ADT: 180

LOCAL

Good

Over: LAKE CREEK

088320801, Calhoun, IA

Built 1990 Load: 45.4 t ADT: 20

FM

Good

Over: FIELD STREAM

082362202, Carroll, IA

Built 1989 Load: 45.4 t ADT: 100

FM

Good

Over: SPRING BRANCH

083341602, Carroll, IA

Built 1997 Load: 45.4 t ADT: 1,186

FM

Good

Over: BRUSHY FORK CREEK

083351811, Carroll, IA

Built 1990 Load: 45.4 t ADT: 638

FM

Good

Over: FIELD STREAM

084362501, Carroll, IA

Built 2006 Load: 45.4 t ADT: 34

CITY STREET

Good

Over: W BR WAPSINONOC CREEK

079041705, Cedar, IA

Built 1997 Load: 45.4 t ADT: 77

FM

Good

Over: ROCK CREEK

080010303, Cedar, IA

Built 2008 Load: 45.4 t ADT: 70

FM

Good

Over: SUGAR CREEK

081021901, Cedar, IA

Built 2007 Load: 45.4 t ADT: 60

330TH ST

Good

Over: BIG MEADOW CREEK

096360301, Clay, IA

Built 1990 Load: 45.4 t ADT: 81

LOCAL RD

Good

Over: SMALL

097362102, Clay, IA

Built 2003 Load: 45.4 t ADT: 112

278TH ST

Good

Over: ROCK CREEK

081E13506, Clinton, IA

Built 2015 Load: 45.4 t ADT: 26

COUNTRY ROAD

Good

Over: BEAVER CREEK

081272001, Dallas, IA

Built 2003 Load: 45.4 t ADT: 26

US 34 WB

Good

Over: BNSF RR

3.1 mi. W of Jct. US 61, Des Moines, IA

Built 2003 Load: 45.4 t ADT: 4,700

US 34 EB

Good

Over: BNSF RR

3.1 mi. W of Jct. US 61, Des Moines, IA

Built 2003 Load: 45.4 t ADT: 4,700

LOCAL

Good

Over: JACK CREEK

0983233, Emmet, IA

Built 2002 Load: 45.4 t ADT: 34

FM

Good

Over: SOLDIER CREEK

100322801, Emmet, IA

Built 1994 Load: 45.4 t ADT: 279

LINDEN ST

Good

Over: OTTER CREEK

000000000, Fayette, IA

Built 1993 Load: 45.4 t ADT: 131

LOCAL

Good

Over: BEAVER CREEK

096151303, Floyd, IA

Built 2002 Load: 45.4 t ADT: 29

FM TIMBER AVE

Good

Over: BEEDS CREEK

092193302, Franklin, IA

Built 2004 Load: 45.4 t ADT: 403

A AVE / N58

Good

Over: DRAINAGE DITCH 9-13

082323002, Greene, IA

Built 2005 Load: 45.4 t ADT: 329

LOCAL

Good

Over: ROCK CREEK

070071803, Henry, IA

Built 1993 Load: 45.4 t ADT: 21

Showing 15,151-15,200 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.