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: NORTH ENGLISH RIVER

079122002, Iowa, IA

Built 2008 Load: 38.2 t ADT: 520

FM

Good

Over: BIG BEAR CREEK

080121506, Iowa, IA

Built 1998 Load: 38.2 t ADT: 630

S 80TH AVE W

Good

Over: SMALL STREAM

078190605, Jasper, IA

Built 2014 Load: 38.2 t ADT: 16

LOCAL

Good

Over: NORTH SKUNK RIVER

080180904, Jasper, IA

Built 2008 Load: 38.2 t ADT: 35

N 115TH AVE W

Good

Over: SILVER CREEK

081210601, Jasper, IA

Built 2014 Load: 38.2 t ADT: 15

LOC 145TH AVE

Good

Over: E FORK DES MOINES RIVER

097282006, Kossuth, IA

Built 1997 Load: 38.2 t ADT: 35

190TH ST

Good

Over: MUD CREEK

1.1 Mi E of X38, Lee, IA

Built 2021 Load: 38.2 t ADT: 90

FM

Good

Over: PITMAN CREEK

068052104, Lee, IA

Built 1989 Load: 38.2 t ADT: 1,400

FM

Good

Over: WALNUT CREEK

072391302, Montgomery, IA

Built 1988 Load: 38.2 t ADT: 61

LOCAL

Good

Over: TRIB SEVEN MILE

073362002, Montgomery, IA

Built 1999 Load: 38.2 t ADT: 20

FM

Good

Over: INDIAN CREEK

073393201, Montgomery, IA

Built 2010 Load: 38.2 t ADT: 20

FM

Good

Over: FLOYD RIVER

097423002, O'Brien, IA

Built 1989 Load: 38.2 t ADT: 549

FM

Good

Over: OLD CHANNEL DES MOINES R

094311603, Palo Alto, IA

Built 1994 Load: 38.2 t ADT: 669

IA 60 SB

Good

Over: STREAM

0.7 mi S of SR C12, Plymouth, IA

Built 2004 Load: 38.2 t ADT: 3,200

US 59

Good

Over: STREAM

0.2 mi. S of S Jct SR G30, Pottawattamie, IA

Built 2021 Load: 38.2 t ADT: 1,740

LOCAL

Good

Over: HOG BRANCH

069321802, Taylor, IA

Built 2010 Load: 38.2 t ADT: 26

290TH ST

Good

Over: CREEK

067080503, Van Buren, IA

Built 2005 Load: 38.2 t ADT: 50

FM

Good

Over: LICK CREEK

069100105, Van Buren, IA

Built 2000 Load: 38.2 t ADT: 80

90TH AVE

Good

Over: LITTLE SOAP CREEK

071133506, Wapello, IA

Built 2011 Load: 38.2 t ADT: 80

LOCAL

Good

Over: BRUSH CREEK

071143006, Wapello, IA

Built 1991 Load: 38.2 t ADT: 21

LOCAL

Good

Over: BRUSHY CREEK

087271104, Webster, IA

Built 1989 Load: 38.2 t ADT: 46

OSCEOLA AVE

Good

Over: PRAIRIE CREEK

088282804, Webster, IA

Built 2019 Load: 38.2 t ADT: 80

P33 GEORGE AVE

Good

Over: SPRING CREEK

088300104, Webster, IA

Built 2019 Load: 38.2 t ADT: 90

BLUFF ST

Good

Over: PERRY CREEK

000000000, Woodbury, IA

Built 2010 Load: 38.2 t ADT: 1,181

LOCAL

Good

Over: CREEK

096143501, Chickasaw, IA

Built 2006 Load: 38.3 t ADT: 29

I AVE

Good

Over: SHORT CREEK

084312102, Greene, IA

Built 2006 Load: 38.3 t ADT: 30

WHITE AVE

Good

Over: SEWER CREEK

097393402, O'Brien, IA

Built 2000 Load: 38.3 t ADT: 50

390TH STREET

Good

Over: STREAM

076403402, Pottawattamie, IA

Built 2022 Load: 38.3 t ADT: 15

120TH ST

Good

Over: STREAM

093131801, Bremer, IA

Built 1997 Load: 38.4 t ADT: 26

IA 57

Good

Over: BEAVER CREEK

0.3 mi. W of W Jct. IA 14, Butler, IA

Built 2003 Load: 38.4 t ADT: 2,430

US 218 NB

Good

Over: WEST BR SUGAR CREEK

0.2 mi. N of Jct. SR J-40, Lee, IA

Built 2003 Load: 38.4 t ADT: 4,550

US 218 SB

Good

Over: WEST BR SUGAR CREEK

0.2 mi. N of Jct. SR J40, Lee, IA

Built 2003 Load: 38.4 t ADT: 4,550

FM

Good

Over: MUD CREEK

079222901, Polk, IA

Built 1986 Load: 38.4 t ADT: 278

FM

Good

Over: W FORK GRAND RIVER

068301905, Ringgold, IA

Built 1985 Load: 38.4 t ADT: 71

US 71

Good

Over: BLUEGRASS CREEK

1.4 mi. S of Jct. SR F32, Audubon, IA

Built 2006 Load: 38.5 t ADT: 3,080

BRANDON RD

Good

Over: SPRING CREEK

87-11-23-03, Black Hawk, IA

Built 1990 Load: 38.5 t ADT: 687

210TH ST

Good

Over: CRANE CREEK

092123201, Bremer, IA

Built 1992 Load: 38.5 t ADT: 49

EUCLID AV

Good

Over: STREAM

092141112, Bremer, IA

Built 1998 Load: 38.5 t ADT: 20

110TH ST

Good

Over: BUCK CREEK

093110901, Bremer, IA

Built 2004 Load: 38.5 t ADT: 49

MIDWAY AVE

Good

Over: STREAM

0911219, Bremer, IA

Built 2012 Load: 38.5 t ADT: 59

LOCAL

Good

Over: COLD WATER CREEK

094192602, Cerro Gordo, IA

Built 2006 Load: 38.5 t ADT: 11

FM-HIGH CTRY.RD

Good

Over: MILL CREEK

092400403, Cherokee, IA

Built 1991 Load: 38.5 t ADT: 50

LOCAL

Good

Over: CREEK

094131101, Chickasaw, IA

Built 1995 Load: 38.5 t ADT: 35

LOCAL

Good

Over: DRY RUN CREEK

095143102, Chickasaw, IA

Built 1990 Load: 38.5 t ADT: 49

432ND AVE.

Good

Over: SPRING CREEK

083E63404, Clinton, IA

Built 1971 Load: 38.5 t ADT: 780

FM

Good

Over: GRAND RIVER

068261708, Decatur, IA

Built 1984 Load: 38.5 t ADT: 20

US 18 EB

Good

Over: I&M RR

0.4 mi. E of Jct. SR B35, Floyd, IA

Built 1999 Load: 38.5 t ADT: 4,450

WAUBONGIE AVE

Good

Over: STREAM

070410101, Fremont, IA

Built 2007 Load: 38.5 t ADT: 11

US 20 WB

Good

Over: SOUTH BEAVER CREEK

0.1 MILE W OF JCT SR T19, Grundy, IA

Built 2003 Load: 38.5 t ADT: 4,550

FM

Good

Over: MASON CREEK

079322603, Guthrie, IA

Built 1989 Load: 38.5 t ADT: 50

Showing 13,701-13,750 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.