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

FM

Good

Over: CROOKED CREEK

069302601, Ringgold, IA

Built 1992 Load: 39.6 t ADT: 60

ST ANNES RD

Good

Over: MCDONALDS CREEK

080E41901, Scott, IA

Built 1988 Load: 39.6 t ADT: 680

FM

Good

Over: LIZARD CREEK

089300201, Webster, IA

Built 2003 Load: 39.6 t ADT: 40

LOCAL

Good

Over: WEST FORK

089441602, Woodbury, IA

Built 2003 Load: 39.6 t ADT: 50

FM

Good

Over: SHELL ROCK RIVER

091142805, Bremer, IA

Built 1994 Load: 39.7 t ADT: 88

IA 141

Good

Over: BRUSHY CREEK

4.5 MI. W OF Sec. Rd. N44, Carroll, IA

Built 1976 Load: 39.7 t ADT: 1,500

FM

Good

Over: N WYACONDAH CREEK

067120901, Davis, IA

Built 2005 Load: 39.7 t ADT: 110

FM

Good

Over: LITTLE FOX CREEK

068122604, Davis, IA

Built 2003 Load: 39.7 t ADT: 80

FM

Good

Over: FABIUS CREEK

068153308, Davis, IA

Built 1998 Load: 39.7 t ADT: 45

LOCAL

Good

Over: SMALL STREAM

086210904, Hardin, IA

Built 1994 Load: 39.7 t ADT: 30

US 218 NB

Good

Over: BNSF RR

0.3 mi. W of E Jct US 218, Henry, IA

Built 2001 Load: 39.7 t ADT: 4,400

S 120TH AVE E

Good

Over: BUCKLEY CREEK

078173101, Jasper, IA

Built 2000 Load: 39.7 t ADT: 15

FM

Good

Over: SOUTH SKUNK RIVER

074110308, Keokuk, IA

Built 1982 Load: 39.7 t ADT: 200

IA 330 SB

Good

Over: NORTH TIMBER CREEK

2.9 MILES S OF JCT US 30, Marshall, IA

Built 1979 Load: 39.7 t ADT: 9,000

LOCAL ROAD

Good

Over: TEN MILE CREEK

000000000, Winneshiek, IA

Built 2010 Load: 39.7 t ADT: 49

HICKORY AVENUE

Good

Over: KEMP CREEK

072342906, Adams, IA

Built 2006 Load: 39.8 t ADT: 71

370TH AVE

Good

Over: CREEK

080E51004, Clinton, IA

Built 2017 Load: 39.8 t ADT: 11

350TH AVE

Good

Over: SMALL STREAM

081E52902, Clinton, IA

Built 1998 Load: 39.8 t ADT: 460

260TH ST

Good

Over: CREEK

081E53001, Clinton, IA

Built 1940 Load: 39.8 t ADT: 35

FM

Good

Over: BOYER RIVER

085383303, Crawford, IA

Built 2002 Load: 39.8 t ADT: 45

LOCAL

Good

Over: BEAVER CREEK

078320200, Guthrie, IA

Built 2009 Load: 39.8 t ADT: 15

330TH ST

Good

Over: WEST FORK NODAWAY RIVER

74332865, Adair, IA

Built 2012 Load: 39.9 t ADT: 51

N54 DELTA AVE

Good

Over: NINE MILE CREEK

4.8 mi N of IA 92 on N54, Adair, IA

Built 2016 Load: 39.9 t ADT: 34

PINEWOOD AVE

Good

Over: MIDDLE RIVER

0.8 mi S of G15, Adair, IA

Built 2017 Load: 39.9 t ADT: 72

MARION AVE

Good

Over: NORTH TURKEY CREEK

77313005, Adair, IA

Built 2014 Load: 39.9 t ADT: 35

QUEBEC AVE

Good

Over: MIDDLE RIVER

2.2 mi S of G15 on Quebec, Adair, IA

Built 2021 Load: 39.9 t ADT: 21

G15 (130TH ST)

Good

Over: NORTH TURKEY CREEK

2.6 mi west of hwy 25, Adair, IA

Built 2012 Load: 39.9 t ADT: 60

LIVING SPRINGS RD

Good

Over: YELLOW RIVER

096060307, Allamakee, IA

Built 2022 Load: 39.9 t ADT: 26

IRISH HOLLOW RD

Good

Over: BR UPPER IOWA RIVER

100042005, Allamakee, IA

Built 2013 Load: 39.9 t ADT: 39

13TH AVE

Good

Over: BRANCH OF STEIN CREEK

084122702, Benton, IA

Built 1998 Load: 39.9 t ADT: 15

IVORY AVE

Good

Over: QUARTER SECTION RUN CR

091132802, Bremer, IA

Built 2019 Load: 39.9 t ADT: 78

FM

Good

Over: BUFFALO CREEK

087070205, Buchanan, IA

Built 2003 Load: 39.9 t ADT: 196

280TH ST

Good

Over: SMALL STREAM

087090201, Buchanan, IA

Built 2020 Load: 39.9 t ADT: 20

120TH STREET

Good

Over: PURGATORY CREEK

085331301, Carroll, IA

Built 2011 Load: 39.9 t ADT: 26

X30 BAKER AVE

Good

Over: WAPSINONOC CREEK

079042904, Cedar, IA

Built 2019 Load: 39.9 t ADT: 2,480

LOCAL-520TH ST

Good

Over: MAPLE RIVER

092392801, Cherokee, IA

Built 2012 Load: 39.9 t ADT: 26

300TH ST

Good

Over: STONEY CREEK

097382401, Clay, IA

Built 2005 Load: 39.9 t ADT: 26

EMBLEM RD

Good

Over: COX CREEK

092051703, Clayton, IA

Built 2008 Load: 39.9 t ADT: 135

GRAPE RD

Good

Over: DRY MILL CREEK

00000, Clayton, IA

Built 2011 Load: 39.9 t ADT: 79

FM 295TH ST

Good

Over: MAQUOKETA RIVER

087041105, Delaware, IA

Built 1985 Load: 39.9 t ADT: 69

285TH ST

Good

Over: SILVER CREEK

087060503, Delaware, IA

Built 2021 Load: 39.9 t ADT: 26

RAINBOW RD

Good

Over: SMALL STREAM

090041405, Delaware, IA

Built 2004 Load: 39.9 t ADT: 20

250TH ST

Good

Over: CREEK

098352701, Dickinson, IA

Built 2013 Load: 39.9 t ADT: 20

M27 (130TH AVE)

Good

Over: STONY CREEK

098382202, Dickinson, IA

Built 2013 Load: 39.9 t ADT: 1,008

Q AVE

Good

Over: UNNAMED CREEK

093092802, Fayette, IA

Built 2020 Load: 39.9 t ADT: 33

220TH ST

Good

Over: FLOOD CREEK

095172201, Floyd, IA

Built 2017 Load: 39.9 t ADT: 29

I-35

Good

Over: DRAINAGE DITCH

2.1 mi. N of jct. IA 3, Franklin, IA

Built 1973 Load: 39.9 t ADT: 16,700

LOCAL

Good

Over: STREAM

078332400, Guthrie, IA

Built 2010 Load: 39.9 t ADT: 20

360TH ST

Good

Over: SKUNK RIVER

086241405, Hamilton, IA

Built 2013 Load: 39.9 t ADT: 80

140TH ST

Good

Over: WEST BRANCH IA RIVER

094241701, Hancock, IA

Built 2016 Load: 39.9 t ADT: 36

Showing 14,101-14,150 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.