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

160TH AVE

Good

Over: PLUM CREEK

096281501, Kossuth, IA

Built 2019 Load: 40.2 t ADT: 81

FM 220TH AVE

Good

Over: MIDDLE BRANCH BLUE EARTH

099271002, Kossuth, IA

Built 2011 Load: 40.2 t ADT: 159

CO RD X 17

Good

Over: SHORT CREEK

075051008, Louisa, IA

Built 2011 Load: 40.2 t ADT: 540

A42 240TH ST

Good

Over: ALBERTSON CREEK

098472201, Lyon, IA

Built 2019 Load: 40.2 t ADT: 1,176

K30 DOVE AVE

Good

Over: SYKES CREEK

099470104, Lyon, IA

Built 2019 Load: 40.2 t ADT: 450

JAY AVE

Good

Over: TOM CREEK

100442702, Lyon, IA

Built 2015 Load: 40.2 t ADT: 30

ASHLEY AVE

Good

Over: BLOOD RUN CREEK

100482102, Lyon, IA

Built 2018 Load: 40.2 t ADT: 21

140TH AVE

Good

Over: STREAM

074192904, Marion, IA

Built 2012 Load: 40.2 t ADT: 26

310TH ST

Good

Over: SNIPE CREEK

082192001, Marshall, IA

Built 2012 Load: 40.2 t ADT: 26

B63 490TH ST

Good

Over: DD84

094342601, Palo Alto, IA

Built 2021 Load: 40.2 t ADT: 309

310TH ST

Good

Over: MUDDY CREEK

9045240110, Plymouth, IA

Built 2017 Load: 40.2 t ADT: 26

NW 13TH ST

Good

Over: ROCK CREEK

080241601, Polk, IA

Built 2016 Load: 40.2 t ADT: 95

GRAND AVE

Good

Over: JORDAN CREEK

City of West Des Moines, Polk, IA

Built 2015 Load: 40.2 t ADT: 3,865

255TH AVE

Good

Over: STREAM

070291504, Ringgold, IA

Built 2017 Load: 40.2 t ADT: 29

D59 360TH ST

Good

Over: CREEK

086371601, Sac, IA

Built 2014 Load: 40.2 t ADT: 330

CORY AVE

Good

Over: ELK CREEK

088383202, Sac, IA

Built 2010 Load: 40.2 t ADT: 170

Y 68

Good

Over: MCDONALDS CREEK

080E41804, Scott, IA

Built 2012 Load: 40.2 t ADT: 2,470

195TH ST

Good

Over: SPENCER CREEK

078E50607, Scott, IA

Built 2010 Load: 40.2 t ADT: 3,090

Y30 20TH AVE

Good

Over: MUD CREEK

079E10902, Scott, IA

Built 2021 Load: 40.2 t ADT: 610

305TH ST

Good

Over: CREEK

080E40803, Scott, IA

Built 2020 Load: 40.2 t ADT: 71

LOCAL

Good

Over: LONG BRANCH

802837, Shelby, IA

Built 2013 Load: 40.2 t ADT: 41

FM

Good

Over: SIX MILE CREEK

094482402, Sioux, IA

Built 1971 Load: 40.2 t ADT: 379

B AVE

Good

Over: SUGAR CREEK

084161702, Tama, IA

Built 2022 Load: 40.2 t ADT: 34

IDAHO AVE

Good

Over: BRANCH WEST 102 RIVER

070340402, Taylor, IA

Built 2016 Load: 40.2 t ADT: 26

150TH ST

Good

Over: WEST 102 RIVER

070353501, Taylor, IA

Built 2011 Load: 40.2 t ADT: 40

H45 240TH ST

Good

Over: SMALL STREAM

071311803, Union, IA

Built 2022 Load: 40.2 t ADT: 40

FM

Good

Over: TWELVE MILE CREEK

073302101, Union, IA

Built 2010 Load: 40.2 t ADT: 477

G62 ROOSEVELT ST

Good

Over: FLANK CREEK

074221101, Warren, IA

Built 2016 Load: 40.2 t ADT: 50

S23 S CENTRAL AVE

Good

Over: MILL CREEK

074222704, Warren, IA

Built 2021 Load: 40.2 t ADT: 400

W64 VINE AVE

Good

Over: SMALL NATURAL STREAM

77062202, Washington, IA

Built 2015 Load: 40.2 t ADT: 1,230

J54 EDISON RD

Good

Over: STREAM

067200401, Wayne, IA

Built 2020 Load: 40.2 t ADT: 80

S43 180TH ST

Good

Over: JACKSON CREEK

069211304, Wayne, IA

Built 2020 Load: 40.2 t ADT: 90

S43 170TH ST

Good

Over: JORDAN CREEK

070212602, Wayne, IA

Built 2018 Load: 40.2 t ADT: 30

160TH ST

Good

Over: SOLDIER CREEK

089280401, Webster, IA

Built 2016 Load: 40.2 t ADT: 46

210TH AVE

Good

Over: CREEK

1 mile south of 125th St, Winneshiek, IA

Built 2014 Load: 40.2 t ADT: 78

LOCAL

Good

Over: SMALL

098081304, Winneshiek, IA

Built 1988 Load: 40.2 t ADT: 442

A 46

Good

Over: TURKEY RIVER

0.4 Mi from 345th Ave, Winneshiek, IA

Built 2018 Load: 40.2 t ADT: 766

D30 185TH ST

Good

Over: WOLF CREEK

88451303, Woodbury, IA

Built 2015 Load: 40.2 t ADT: 45

JEWELL AVE

Good

Over: STREAM

089430702, Woodbury, IA

Built 2021 Load: 40.2 t ADT: 50

342ND ST

Good

Over: DRAINAGE DITCH

East of Fir Ave., Worth, IA

Built 2021 Load: 40.2 t ADT: 35

LOCAL

Good

Over: OTTER CREEK

093253302, Wright, IA

Built 2006 Load: 40.2 t ADT: 26

W45 SLATER AVE

Good

Over: BUFFALO CREEK

089082511, Buchanan, IA

Built 2002 Load: 40.3 t ADT: 982

LOCAL

Good

Over: E FK WAPSIPINICON RIVER

094122201, Chickasaw, IA

Built 2003 Load: 40.3 t ADT: 30

US 218 NB

Good

Over: BIG CREEK

1.3 mi. N of S Jct. US 34, Henry, IA

Built 2000 Load: 40.3 t ADT: 6,050

US 218 SB

Good

Over: NORTH BRANCH FISH CREEK

1.1 mi. N of Jct. SR J-20, Henry, IA

Built 2003 Load: 40.3 t ADT: 4,850

FM

Good

Over: NORTH ENGLISH RIVER

079113208, Iowa, IA

Built 2002 Load: 40.3 t ADT: 320

COUNTY RD. D-61

Good

Over: WHITE WATER

086011102, Jones, IA

Built 2005 Load: 40.3 t ADT: 579

IA 27 SB

Good

Over: SUGAR CREEK

4.7 mi. S of IA 2, Lee, IA

Built 2002 Load: 40.3 t ADT: 3,600

FM

Good

Over: SOUTH CHARITON RIVER

069210104, Wayne, IA

Built 2006 Load: 40.3 t ADT: 50

107TH AVE

Good

Over: YELLOW RIVER

0.1 MI S of Maple Valley, Winneshiek, IA

Built 2018 Load: 40.3 t ADT: 29

Showing 14,301-14,350 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.