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

E57 260TH ST

Good

Over: GRANT #5 OPEN DITCH

0.4 Mi E 610th Ave, Story, IA

Built 2016 Load: 40.5 t ADT: 120

FM

Good

Over: EAST PLATTE RIVER

071312402, Union, IA

Built 2009 Load: 40.5 t ADT: 927

FM

Good

Over: N AVERY CREEK

073153002, Wapello, IA

Built 2008 Load: 40.5 t ADT: 1,250

IA 22

Good

Over: BULGERS RUN

4.8 mi. E of Jct. Iowa 1, Washington, IA

Built 2021 Load: 40.5 t ADT: 3,090

VALE RD

Good

Over: STREAM

070210801, Wayne, IA

Built 2018 Load: 40.5 t ADT: 30

IA 175

Good

Over: WEST BUTTRICK CREEK

2.1 mi. E of Sec. Rd. P29, Webster, IA

Built 2018 Load: 40.5 t ADT: 960

D60 350TH ST

Good

Over: BUTTRICK CREEK

086301001, Webster, IA

Built 2021 Load: 40.5 t ADT: 559

350TH ST

Good

Over: BUFFALO CREEK

098263401, Winnebago, IA

Built 2020 Load: 40.5 t ADT: 21

111TH AVE

Good

Over: YELLOW RIVER

S of Int of Maple Valley, Winneshiek, IA

Built 2015 Load: 40.5 t ADT: 69

FM

Good

Over: CANOE CREEK

099082305, Winneshiek, IA

Built 2002 Load: 40.5 t ADT: 1,581

LOCAL

Good

Over: BIG WHISKEY CREEK

088461802, Woodbury, IA

Built 2004 Load: 40.5 t ADT: 45

FM

Good

Over: CREEK

0894532, Woodbury, IA

Built 2008 Load: 40.5 t ADT: 649

230 AVE

Good

Over: WEST CREEK

073252006, Clarke, IA

Built 1999 Load: 40.6 t ADT: 71

LOCAL

Good

Over: OLD MANS CREEK

079110401, Iowa, IA

Built 2006 Load: 40.6 t ADT: 15

US 151 NB

Good

Over: MAQUOKETA RIVER

1.1 MI. N OF JCT. IA 38, Jones, IA

Built 2003 Load: 40.6 t ADT: 4,400

US 151 SB

Good

Over: MAQUOKETA RIVER

1.1 MI. N OF JCT. IA 38, Jones, IA

Built 2003 Load: 40.6 t ADT: 4,400

US 151 SB

Good

Over: KITTY CREEK

0.4 MI. N OF JCT. SR X44, Jones, IA

Built 2002 Load: 40.6 t ADT: 4,200

LOCAL

Good

Over: STREAM

074191001, Marion, IA

Built 2007 Load: 40.6 t ADT: 51

US 30 EB

Good

Over: UPRR

0.5 MILE W OF JCT IA 146, Marshall, IA

Built 2004 Load: 40.6 t ADT: 7,050

US 30 WB

Good

Over: UP RR

1.0 MILE W OF JCT SR T31, Marshall, IA

Built 2001 Load: 40.6 t ADT: 7,350

IA 22

Good

Over: OVER RR SPUR (IPSCO)

1.2 mi. W of Jct. SR Y36, Muscatine, IA

Built 1996 Load: 40.6 t ADT: 1,490

R77/600TH AVE

Good

Over: BEAR CREEK

085231104, Story, IA

Built 2003 Load: 40.6 t ADT: 948

FM 1849

Good

Over: STEIN CREEK

084122202, Benton, IA

Built 1989 Load: 40.7 t ADT: 10

IA 128

Good

Over: DRY MILL CREEK

2.4 MI. E OF JCT. IA 13, Clayton, IA

Built 1979 Load: 40.7 t ADT: 1,420

LOCAL

Good

Over: MINOR DRAINAGE

070410301, Fremont, IA

Built 2007 Load: 40.7 t ADT: 11

US 67

Good

Over: SPENCER CREEK

3.0 mi. S of Jct. I-80, Scott, IA

Built 1996 Load: 40.7 t ADT: 8,400

SB US 169

Good

Over: CC RR

0.5 mi. S of IA 7, Webster, IA

Built 2011 Load: 40.7 t ADT: 4,450

240TH STREET

Good

Over: SAYLINGS CREEK

071321601, Adams, IA

Built 2008 Load: 40.8 t ADT: 11

LOCAL

Good

Over: STREAM

069161202, Appanoose, IA

Built 2008 Load: 40.8 t ADT: 35

LOCAL

Good

Over: PRATT CK

085122301, Benton, IA

Built 2007 Load: 40.8 t ADT: 29

LOCAL

Good

Over: BLUE CREEK

086091305, Benton, IA

Built 2007 Load: 40.8 t ADT: 33

US 30 EB

Good

Over: UNNAMED CREEK

1.2 MI. W. OF CO. RD. V66, Benton, IA

Built 2022 Load: 40.8 t ADT: 3,800

IA 58

Good

Over: BLACK HAWK CREEK

1.0 mi. N of Jct. U.S. 63, Black Hawk, IA

Built 1995 Load: 40.8 t ADT: 5,200

E SHAULIS RD

Good

Over: SINK CREEK

CITY CULVERT NO. 41C, Black Hawk, IA

Built 1988 Load: 40.8 t ADT: 410

NB US 63

Good

Over: QUARTER SECTION RUN CRK.

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

Built 1994 Load: 40.8 t ADT: 2,900

1ST ST EAST

Good

Over: MELONE CREEK

T89N-R9W-S35-N0.0-E14.5, Buchanan, IA

Built 2019 Load: 40.8 t ADT: 6,094

300TH ST

Good

Over: DRY CREEK

087071501, Buchanan, IA

Built 2014 Load: 40.8 t ADT: 41

235TH ST

Good

Over: SMALL STREAM

108808, Buchanan, IA

Built 2016 Load: 40.8 t ADT: 88

T25 (HICKORY AV

Good

Over: SMALL STREAM

090170502, Butler, IA

Built 2008 Load: 40.8 t ADT: 530

F58 IA 927

Good

Over: SMALL STREAM

079013403, Cedar, IA

Built 2017 Load: 40.8 t ADT: 3,050

HEATHER

Good

Over: W BRANCH BEAVER DAM CRK

000000000, Cerro Gordo, IA

Built 2010 Load: 40.8 t ADT: 30

500TH ST

Good

Over: BADGER CREEL

092391801, Cherokee, IA

Built 2022 Load: 40.8 t ADT: 60

205TH STREET

Good

Over: CREEK

082E22903, Clinton, IA

Built 2005 Load: 40.8 t ADT: 51

Y54 (230TH AVE)

Good

Over: SMALL CREEK

082E32902, Clinton, IA

Built 2013 Load: 40.8 t ADT: 360

237TH AVE

Good

Over: CREEK

081E31708, Clinton, IA

Built 2009 Load: 40.8 t ADT: 21

FM

Good

Over: SMALL STREAM

070120804, Davis, IA

Built 2008 Load: 40.8 t ADT: 80

FM

Good

Over: BRUSH CREEK

069032604, Des Moines, IA

Built 2006 Load: 40.8 t ADT: 51

LEUCHS RD

Good

Over: CURRAM BRANCH

8801 19 9500, Dubuque, IA

Built 2016 Load: 40.8 t ADT: 59

HAMMERAND RD

Good

Over: BLOODY RUN CREEK

090E21703, Dubuque, IA

Built 2022 Load: 40.8 t ADT: 285

EAST 22ND ST

Good

Over: BEE BRANCH

NE OF KNEIST/ELM ST, Dubuque, IA

Built 2017 Load: 40.8 t ADT: 4,246

Showing 14,401-14,450 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.