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

53RD ST TRAIL

Good

Over: WEST BRANCH BLUE CREEK

086092404, Benton, IA

Built 2020 Load: 32.4 t ADT: 5

22ND AVE DR

Good

Over: BEAR CREEK

086102104, Benton, IA

Built 2021 Load: 32.4 t ADT: 108

51ST ST DR

Good

Over: ROCK CK

083111003, Benton, IA

Built 2019 Load: 32.4 t ADT: 15

V37

Good

Over: WOLF CREEK

086121902, Benton, IA

Built 2021 Load: 32.4 t ADT: 1,316

MAIN ST

Good

Over: DRY RUN CREEK

000000000, Black Hawk, IA

Built 1962 Load: 32.4 t ADT: 10,989

IA 281

Good

Over: POYNER CREEK

2.3 MI N OF JCT SR D20, Black Hawk, IA

Built 2014 Load: 32.4 t ADT: 2,860

W CEDAR-WAPSI RD

Good

Over: CHICAGO CENTRAL RAILROAD

90-14-13-01-10, Black Hawk, IA

Built 2016 Load: 32.4 t ADT: 2,268

GREENHILL RD

Good

Over: STREAM

000000000, Black Hawk, IA

Built 1990 Load: 32.4 t ADT: 10,300

WATERBURY DR

Good

Over: UNIV BR DRY RUN CREEK

0.14 MI W OF LEXINGTON DR, Black Hawk, IA

Built 2009 Load: 32.4 t ADT: 32

TECHNOLOGY PKWY

Good

Over: S BR DRY RUN CREEK

0.06 MI W OF HUDSON RD, Black Hawk, IA

Built 2010 Load: 32.4 t ADT: 1,585

WYNNEWOOD DR

Good

Over: DRAINAGE

0.09 MI N OF FIELDSTONE, Black Hawk, IA

Built 2007 Load: 32.4 t ADT: 132

US 63

Good

Over: CC & P RR

0.9 mi. N of US 218, Black Hawk, IA

Built 2019 Load: 32.4 t ADT: 11,000

MONTONA RD

Good

Over: HONEY CREEK

083260714, Boone, IA

Built 2017 Load: 32.4 t ADT: 110

140TH ST

Good

Over: IOWAY CREEK

085252701, Boone, IA

Built 2016 Load: 32.4 t ADT: 30

U AVE

Good

Over: MONTGOMERY CREEK

085253302, Boone, IA

Built 2019 Load: 32.4 t ADT: 30

IA 3

Good

Over: BUCK CREEK

0.6 MI. E. OF CO. RD. V56, Bremer, IA

Built 2018 Load: 32.4 t ADT: 1,960

C28 165TH ST

Good

Over: WATERWAY

092120203, Bremer, IA

Built 2018 Load: 32.4 t ADT: 177

200TH ST

Good

Over: QUARTER SECTION RUN

092132601, Bremer, IA

Built 2015 Load: 32.4 t ADT: 44

C33 190TH ST

Good

Over: CEDAR RIVER

092142101, Bremer, IA

Built 2015 Load: 32.4 t ADT: 1,002

310TH ST

Good

Over: TWO MILE CREEK

093140201, Bremer, IA

Built 2019 Load: 32.4 t ADT: 33

IA 116

Good

Over: DRY RUN CREEK

0.1 MI.S.OF JCT.3, Bremer, IA

Built 2015 Load: 32.4 t ADT: 14,800

US 63

Good

Over: QUARTER SECTION RUN

At Jct. Iowa 3, Bremer, IA

Built 2010 Load: 32.4 t ADT: 6,400

IA 3

Good

Over: QUARTER SECTION RUN

0.1 mi. E OF US 63 & IA 3, Bremer, IA

Built 2010 Load: 32.4 t ADT: 2,830

US 218

Good

Over: DRAINAGE DITCH

0.5 mi. S of Jct. SR C50, Bremer, IA

Built 2012 Load: 32.4 t ADT: 18,700

IA 150

Good

Over: BEAR CREEK

0.9 Mi. N of CR D-47, Buchanan, IA

Built 2013 Load: 32.4 t ADT: 4,650

THOMAS AVE

Good

Over: SMALL STREAM

087073106, Buchanan, IA

Built 2014 Load: 32.4 t ADT: 59

LOCAL SCOTT

Good

Over: SMITH CR

087080204, Buchanan, IA

Built 1989 Load: 32.4 t ADT: 51

OVERLAND AVE

Good

Over: SMALL STREAM

087081602, Buchanan, IA

Built 2020 Load: 32.4 t ADT: 30

MICHEL AVE

Good

Over: SMALL CREEK

00000, Buchanan, IA

Built 2011 Load: 32.4 t ADT: 25

IOWA AVE

Good

Over: SMALL STREAM

087090804, Buchanan, IA

Built 2004 Load: 32.4 t ADT: 79

LOCAL 320TH ST.

Good

Over: SMALL STREAM

087092903, Buchanan, IA

Built 1999 Load: 32.4 t ADT: 26

288TH STREET

Good

Over: SMALL STREAM

087100611, Buchanan, IA

Built 2000 Load: 32.4 t ADT: 11

LOCAL FROST AVE

Good

Over: SMALL STREAM

087101104, Buchanan, IA

Built 2003 Load: 32.4 t ADT: 21

LOCAL 295TH ST.

Good

Over: SMALL STREAM

087101105, Buchanan, IA

Built 2004 Load: 32.4 t ADT: 11

BUTLER AVE

Good

Over: SMALL STREAM

087101912, Buchanan, IA

Built 2006 Load: 32.4 t ADT: 30

228TH ST

Good

Over: SMALL STREAM

088070503, Buchanan, IA

Built 2012 Load: 32.4 t ADT: 51

QUASQUETON BLVD

Good

Over: SMALL STREAM

088082703, Buchanan, IA

Built 2014 Load: 32.4 t ADT: 776

LEE AVENUE

Good

Over: SMALL STREAM

088092308, Buchanan, IA

Built 2000 Load: 32.4 t ADT: 44

KING AVE

Good

Over: SMALL STREAM

R9WT88N350071, Buchanan, IA

Built 2013 Load: 32.4 t ADT: 62

VICTOR AVE

Good

Over: PRAIRIE CREEK

089071502, Buchanan, IA

Built 2014 Load: 32.4 t ADT: 42

208TH STREET

Good

Over: SMALL STREAM

089072505, Buchanan, IA

Built 1992 Load: 32.4 t ADT: 47

215TH ST

Good

Over: SMALL STREAM

8908318550, Buchanan, IA

Built 2016 Load: 32.4 t ADT: 26

LOCAL

Good

Over: SMALL STREAM

089090601, Buchanan, IA

Built 2006 Load: 32.4 t ADT: 47

LOC GRANT AVE

Good

Over: SMALL STREAM

089090704, Buchanan, IA

Built 1973 Load: 32.4 t ADT: 104

LOCAL

Good

Over: SMALL STREAM

089101011, Buchanan, IA

Built 2005 Load: 32.4 t ADT: 73

RIVER RD BLVD

Good

Over: SMALL STREAM

089101303, Buchanan, IA

Built 2000 Load: 32.4 t ADT: 73

LOCAL

Good

Over: SMALL STREAM

08910275000, Buchanan, IA

Built 2005 Load: 32.4 t ADT: 15

LOC UNION AVE

Good

Over: SMALL STREAM

090070404, Buchanan, IA

Built 1988 Load: 32.4 t ADT: 11

LOC 100TH ST

Good

Over: STREAM

090070501, Buchanan, IA

Built 1995 Load: 32.4 t ADT: 44

136TH ST

Good

Over: BUFFALO CR

090082405, Buchanan, IA

Built 2008 Load: 32.4 t ADT: 16

Showing 10,401-10,450 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.