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

SDB

Good

Over: DOWD CREEK

086193601, Hardin, IA

Built 2009 Load: 39.9 t ADT: 766

X13 MARSH AVE

Good

Over: SOUTH BIG CREEK

072053104, Henry, IA

Built 2015 Load: 39.9 t ADT: 120

US 34 IA 163 WB

Good

Over: BNSF

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

Built 2001 Load: 39.9 t ADT: 1,930

YANKEE AVE

Good

Over: SILVER CREEK

099111202, Howard, IA

Built 2012 Load: 39.9 t ADT: 91

LOCAL

Good

Over: LYTLE CREEK

086E22905, Jackson, IA

Built 1999 Load: 39.9 t ADT: 29

F48

Good

Over: PRAIRIE CREEK

080203403, Jasper, IA

Built 2019 Load: 39.9 t ADT: 2,260

MONARCH AVE

Good

Over: CARSON CREEK

079193501, Jasper, IA

Built 2012 Load: 39.9 t ADT: 91

T38

Good

Over: SUGAR CREEK

080171302, Jasper, IA

Built 2022 Load: 39.9 t ADT: 710

INDIGO AVE

Good

Over: COON CREEK

080182503, Jasper, IA

Built 2018 Load: 39.9 t ADT: 91

H28 146TH BLVD

Good

Over: BURR OAK CREEK

073082603, Jefferson, IA

Built 2022 Load: 39.9 t ADT: 100

COUNTY RD E-28

Good

Over: BUFFALO CREEK

084040307, Jones, IA

Built 1995 Load: 39.9 t ADT: 1,237

140TH AVENUE

Good

Over: LITTLE SUGAR CREEK

0.7 mi N of 210th St, Lee, IA

Built 2023 Load: 39.9 t ADT: 20

E16 CENTRALCITYRD

Good

Over: WEST OTTER CREEK

085070701, Linn, IA

Built 2020 Load: 39.9 t ADT: 1,011

530TH ST

Good

Over: NORTH CEDAR CREEK

073203401, Lucas, IA

Built 2022 Load: 39.9 t ADT: 25

LOG AVE

Good

Over: WEST RAT CREEK

098431402, Lyon, IA

Built 2020 Load: 39.9 t ADT: 34

240TH ST

Good

Over: RAT CREEK

098432401, Lyon, IA

Built 2020 Load: 39.9 t ADT: 81

220TH ST

Good

Over: EMERY CREEK

098451101, Lyon, IA

Built 2017 Load: 39.9 t ADT: 46

IBEX AVE

Good

Over: EMERY CREEK

098451202, Lyon, IA

Built 2017 Load: 39.9 t ADT: 46

260TH ST

Good

Over: ALBERTSON CREEK

098473501, Lyon, IA

Built 2017 Load: 39.9 t ADT: 50

G46 WALNUT TRAIL

Good

Over: DRAINAGE

075261203, Madison, IA

Built 2019 Load: 39.9 t ADT: 45

SETTLERS AVE

Good

Over: STREAM

077263102, Madison, IA

Built 2022 Load: 39.9 t ADT: 60

STORY DRIVE

Good

Over: ENGLISH CREEK

074201603, Marion, IA

Built 2022 Load: 39.9 t ADT: 35

PARKER AVE

Good

Over: NORTH TIMBER CREEK

083182202, Marshall, IA

Built 2014 Load: 39.9 t ADT: 104

105TH ST

Good

Over: HONEY CREEK

085190609, Marshall, IA

Built 2016 Load: 39.9 t ADT: 59

155TH ST

Good

Over: MINERVA CREEK

085203503, Marshall, IA

Built 2017 Load: 39.9 t ADT: 30

210TH ST

Good

Over: JORDAN CREEK

084433501, Monona, IA

Built 2020 Load: 39.9 t ADT: 29

FM

Good

Over: WEST NODAWAY

073363303, Montgomery, IA

Built 2003 Load: 39.9 t ADT: 71

LOCAL

Good

Over: DD 2

076040703, Muscatine, IA

Built 2010 Load: 39.9 t ADT: 51

B46 420TH ST

Good

Over: WATERMAN CREEK

095392303, O'Brien, IA

Built 2022 Load: 39.9 t ADT: 26

POLK AVE

Good

Over: MILL CREEK

095411602, O'Brien, IA

Built 2022 Load: 39.9 t ADT: 11

POLK AVE

Good

Over: MILL CREEK

095413302, O'Brien, IA

Built 2021 Load: 39.9 t ADT: 46

340TH ST

Good

Over: WATERMAN CREEK

096390701, O'Brien, IA

Built 2021 Load: 39.9 t ADT: 41

220TH STREET

Good

Over: EAST TARKIO CREEK

068380303, Page, IA

Built 2010 Load: 39.9 t ADT: 5

190TH ST

Good

Over: BROKEN KETTLE CREEK

9247190110, Plymouth, IA

Built 2018 Load: 39.9 t ADT: 30

LOCAL

Good

Over: W FORK DES MOINES RIVER

093312501, Pocahontas, IA

Built 1995 Load: 39.9 t ADT: 34

130TH AVE

Good

Over: CREEK

079E31702, Scott, IA

Built 2020 Load: 39.9 t ADT: 500

85TH AVE

Good

Over: CREEK

080E23304, Scott, IA

Built 2017 Load: 39.9 t ADT: 45

VALLEY DR

Good

Over: SPENCER CREEK

078E50709, Scott, IA

Built 2012 Load: 39.9 t ADT: 2,910

NORTH 7TH ST

Good

Over: SMALL STREAM

D81500610, Shelby, IA

Built 2021 Load: 39.9 t ADT: 114

LOCAL

Good

Over: FLOYD RIVER

096432301, Sioux, IA

Built 2005 Load: 39.9 t ADT: 139

FM

Good

Over: GRAND RIVER

071280206, Union, IA

Built 2001 Load: 39.9 t ADT: 210

REDWOOD AVE

Good

Over: STREAM

071293602, Union, IA

Built 2011 Load: 39.9 t ADT: 20

LOCAL

Good

Over: CREEK

068103005, Van Buren, IA

Built 1999 Load: 39.9 t ADT: 16

LOCAL

Good

Over: COATES CREEK

069081701, Van Buren, IA

Built 1999 Load: 39.9 t ADT: 11

LITTLE SOAP RD

Good

Over: LITTLE SOAP CREEK

071142404, Wapello, IA

Built 2011 Load: 39.9 t ADT: 300

LOCAL ROAD

Good

Over: SOUTH RIVER

075230404, Warren, IA

Built 2008 Load: 39.9 t ADT: 226

FM

Good

Over: S RIVER

075251207, Warren, IA

Built 2003 Load: 39.9 t ADT: 229

FORD ST

Good

Over: BR NORTH RIVER

077253305, Warren, IA

Built 2015 Load: 39.9 t ADT: 60

170TH ST

Good

Over: LIZARD CREEK

089301103, Webster, IA

Built 2021 Load: 39.9 t ADT: 30

SCENIC RIVER RD

Good

Over: UPPER IOWA RIVER

.9 mi e bluffton road, Winneshiek, IA

Built 2021 Load: 39.9 t ADT: 59

Showing 14,151-14,200 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.