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: WELDON RIVER

068241602, Decatur, IA

Built 1994 Load: 35.3 t ADT: 34

H28 260TH ST

Good

Over: SMALL STREAM

072020605, Des Moines, IA

Built 2017 Load: 35.3 t ADT: 130

180TH ST

Good

Over: CEDAR FORK

072042502, Des Moines, IA

Built 2017 Load: 35.3 t ADT: 62

NB US 61

Good

Over: SPRING CREEK

3.9 mi. N of jct. IA 16, Des Moines, IA

Built 1995 Load: 35.3 t ADT: 5,050

PITZ RD

Good

Over: BUNCOMBE CREEK

R2ET87NS1SE, Dubuque, IA

Built 2012 Load: 35.3 t ADT: 44

LOCAL

Good

Over: LITTLE MAQUOKETA RIVER

089E20505, Dubuque, IA

Built 1992 Load: 35.3 t ADT: 737

FM

Good

Over: BLOODY RUN CREEK

090E22806, Dubuque, IA

Built 2001 Load: 35.3 t ADT: 1,119

W AVE

Good

Over: HAUGH CREEK

094101602, Fayette, IA

Built 2005 Load: 35.3 t ADT: 737

H38 220TH ST

Good

Over: LAWRENCE CREEK

071050501, Henry, IA

Built 2022 Load: 35.3 t ADT: 960

H18 140TH ST

Good

Over: LYNN CREEK

073063001, Henry, IA

Built 2016 Load: 35.3 t ADT: 80

JUNIPER AVE

Good

Over: CREEK

091292702, Humboldt, IA

Built 2012 Load: 35.3 t ADT: 11

KEYSTONE AVE

Good

Over: HOG RUN

089390904, Ida, IA

Built 2020 Load: 35.3 t ADT: 35

FM

Good

Over: MAPLE RIVER

089392703, Ida, IA

Built 1998 Load: 35.3 t ADT: 609

F20 AMANA RD

Good

Over: BR IOWA RIVER

T81N, R08W, 19, Johnson, IA

Built 2018 Load: 35.3 t ADT: 160

FM

Good

Over: N SKUNK RIVER

077143306, Mahaska, IA

Built 1991 Load: 35.3 t ADT: 320

586TH AVE

Good

Over: CREEK

073183407, Monroe, IA

Built 2022 Load: 35.3 t ADT: 30

LINDLE AVE

Good

Over: CREEK

077020604, Muscatine, IA

Built 2017 Load: 35.3 t ADT: 82

410TH ST

Good

Over: MILL CREEK

095 41 16 01, O'Brien, IA

Built 2012 Load: 35.3 t ADT: 21

FM

Good

Over: UNNAMED STREAM

096410602, O'Brien, IA

Built 1980 Load: 35.3 t ADT: 409

FM

Good

Over: DD 81

094311705, Palo Alto, IA

Built 1994 Load: 35.3 t ADT: 669

FM

Good

Over: DES MOINES RIVER

095312908, Palo Alto, IA

Built 1996 Load: 35.3 t ADT: 290

EASTERN HILLS DR

Good

Over: STREAM

200' S of Greenview Rd, Pottawattamie, IA

Built 2020 Load: 35.3 t ADT: 1,669

US 65

Good

Over: DYE CREEK

1.8 MI. N OF US 30, Story, IA

Built 1979 Load: 35.3 t ADT: 2,110

9TH ST

Good

Over: MUD CREEK

083152606, Tama, IA

Built 2014 Load: 35.3 t ADT: 57

FM

Good

Over: CEDAR CREEK

072121301, Wapello, IA

Built 2006 Load: 35.3 t ADT: 30

H31 BLADENSBURG RD

Good

Over: JORDAN CREEK

072121701, Wapello, IA

Built 2023 Load: 35.3 t ADT: 90

J44 JUBILEE

Good

Over: WALNUT CREEK

068200503, Wayne, IA

Built 2014 Load: 35.3 t ADT: 25

240TH ST

Good

Over: CREEK

0.2 MI E 315 Av, Winneshiek, IA

Built 2020 Load: 35.3 t ADT: 78

A14

Good

Over: PINE CREEK

0.9 Mi W US 52, Winneshiek, IA

Built 2016 Load: 35.3 t ADT: 157

220TH ST

Good

Over: CREEK

087460301, Woodbury, IA

Built 2018 Load: 35.3 t ADT: 20

LOCAL

Good

Over: MAPLE CREEK

090381501, Buena Vista, IA

Built 2004 Load: 35.4 t ADT: 15

210TH AVE

Good

Over: CREEK

083E21202, Clinton, IA

Built 1995 Load: 35.4 t ADT: 113

170TH AVE.

Good

Over: SMALL STREAM

083E23202, Clinton, IA

Built 1992 Load: 35.4 t ADT: 35

FM

Good

Over: EAST SOLDIER RIVER

084412904, Crawford, IA

Built 1986 Load: 35.4 t ADT: 71

NB US 61 RAMP

Good

Over: VACANT LOTS

IN DUBUQUE AT KERPER BLVD, Dubuque, IA

Built 1991 Load: 35.4 t ADT: 3,650

LOC VALLEY AVE

Good

Over: SILVER CR

099111502, Howard, IA

Built 2001 Load: 35.4 t ADT: 118

380TH

Good

Over: BURR OAK CREEK

098161005, Mitchell, IA

Built 1975 Load: 35.4 t ADT: 44

ECHO AVE

Good

Over: SMALL STREAM

098183502, Mitchell, IA

Built 1987 Load: 35.4 t ADT: 33

LOCAL

Good

Over: LITTLE FLOYD RIVER

097412801, O'Brien, IA

Built 1992 Load: 35.4 t ADT: 41

LOCAL

Good

Over: ELKHORN CREEK

078371201, Shelby, IA

Built 2001 Load: 35.4 t ADT: 82

LOCAL

Good

Over: KEG CREEK

078400501, Shelby, IA

Built 2008 Load: 35.4 t ADT: 26

WILDWOOD RD

Good

Over: SMALL STREAM

1/4 mi. south of 1400th, Shelby, IA

Built 2012 Load: 35.4 t ADT: 21

210TH ST

Good

Over: WEST BR INDIAN CREEK

084233601, Story, IA

Built 1998 Load: 35.4 t ADT: 90

LOCAL-480TH ST

Good

Over: WEST FORK LITTLE SIOUX

092420101, Cherokee, IA

Built 2002 Load: 35.5 t ADT: 71

298TH STREET

Good

Over: MOSQUITO CREEK

077413004, Pottawattamie, IA

Built 1998 Load: 35.5 t ADT: 2,051

FM

Good

Over: NODAWAY RIVER

075333402, Adair, IA

Built 2004 Load: 35.6 t ADT: 79

FM

Good

Over: YELLOW RIVER

096041607, Allamakee, IA

Built 2001 Load: 35.6 t ADT: 79

280TH ST

Good

Over: CREEK

LOCAL 078340503, Audubon, IA

Built 2012 Load: 35.6 t ADT: 91

270 ST

Good

Over: INDIAN CREEK

079363003, Audubon, IA

Built 2000 Load: 35.6 t ADT: 72

150 ST

Good

Over: E NISHNABOTNA RIVER

081343101, Audubon, IA

Built 2000 Load: 35.6 t ADT: 29

Showing 12,901-12,950 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.