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

OLD LINCOLN HWY

Fair

Over: LAPWORTH CREEK

076443608, Pottawattamie, IA

Built 1942 Load: 32.7 t ADT: 2,759

L 20

Fair

Over: PIGEON CREEK

076430612, Pottawattamie, IA

Built 1977 Load: 32.7 t ADT: 2,430

OLD LINCOLN HWY

Fair

Over: HONEY CREEK

077443503, Pottawattamie, IA

Built 1989 Load: 32.7 t ADT: 1,175

RAILROAD HWY

Fair

Over: MOSQUITO CREEK

075431106, Pottawattamie, IA

Built 1963 Load: 32.7 t ADT: 2,071

FRONT ST

Fair

Over: MOSQUITO CREEK

000000000, Pottawattamie, IA

Built 1963 Load: 32.7 t ADT: 2,195

FM

Fair

Over: DRAINAGE

074402003, Pottawattamie, IA

Built 1961 Load: 32.7 t ADT: 417

MCPHERSON AVE

Fair

Over: STREAM

075422007, Pottawattamie, IA

Built 1968 Load: 32.7 t ADT: 240

SCHOOL HILL AVE

Fair

Over: INDIAN CREEK

075431803, Pottawattamie, IA

Built 1980 Load: 32.7 t ADT: 199

MUDHOLLOW ROAD

Fair

Over: INDIAN CREEK

075431814, Pottawattamie, IA

Built 1980 Load: 32.7 t ADT: 428

CATHY LANE

Fair

Over: INDIAN CREEK

075431811, Pottawattamie, IA

Built 1976 Load: 32.7 t ADT: 956

FM-MUDHOLLOW RD

Fair

Over: INDIAN CREEK

075431828, Pottawattamie, IA

Built 1976 Load: 32.7 t ADT: 1,025

FM-MCPHERSON AV

Fair

Over: LITTLE MOSQUITO

075432809, Pottawattamie, IA

Built 1987 Load: 32.7 t ADT: 698

460TH STREET

Fair

Over: GRAYBILL CREEK

076391402, Pottawattamie, IA

Built 1984 Load: 32.7 t ADT: 50

MAGNOLIA ROAD

Fair

Over: HENSCHAL CREEK

076432401, Pottawattamie, IA

Built 1983 Load: 32.7 t ADT: 131

FM-BADGER AVE

Fair

Over: CRESCENT CREEK

076442403, Pottawattamie, IA

Built 1976 Load: 32.7 t ADT: 1,404

FM-JOSLIN AVE

Fair

Over: STREAM

076442609, Pottawattamie, IA

Built 1975 Load: 32.7 t ADT: 300

FM-430TH STREET

Fair

Over: STREAM

077392902, Pottawattamie, IA

Built 1972 Load: 32.7 t ADT: 60

SUMAC ROAD

Fair

Over: SMALL STREAM

077413501, Pottawattamie, IA

Built 1984 Load: 32.7 t ADT: 50

SUMAC ROAD

Fair

Over: STREAM

077423103, Pottawattamie, IA

Built 1977 Load: 32.7 t ADT: 15

HUNTER AVE

Fair

Over: INDIAN CREEK

000000000, Pottawattamie, IA

Built 1988 Load: 32.7 t ADT: 684

HAPPY HOLLOW BL

Fair

Over: INDIAN CREEK

000000000, Pottawattamie, IA

Built 1987 Load: 32.7 t ADT: 232

IVY DRIVE

Fair

Over: INDIAN CREEK

000000000, Pottawattamie, IA

Built 1987 Load: 32.7 t ADT: 684

N 8TH STREET

Fair

Over: INDIAN CREEK

8th St over Indian Creek, Pottawattamie, IA

Built 1988 Load: 32.7 t ADT: 3,786

OLD LINCOLN HWY

Fair

Over: CRESENT CREEK

E75000505, Pottawattamie, IA

Built 2004 Load: 32.7 t ADT: 5,086

CREEK TOP RD

Fair

Over: INDIAN CREEK

UPRR to 10th St, Pottawattamie, IA

Built 1937 Load: 32.7 t ADT: 2,027

CREEK TOP RD

Fair

Over: INDIAN CREEK

Creek Top, 8th to 7th St, Pottawattamie, IA

Built 1937 Load: 32.7 t ADT: 70

SCOTT STREET

Fair

Over: INDIAN CREEK

Scott St over Indian Ck, Pottawattamie, IA

Built 1937 Load: 32.7 t ADT: 2,224

NORTH MAIN ST

Fair

Over: INDIAN CREEK

Main St over Indian Ck, Pottawattamie, IA

Built 1937 Load: 32.7 t ADT: 3,184

PUBLIC PARKING

Fair

Over: INDIAN CREEK

Benton-Frank over Indian, Pottawattamie, IA

Built 1937 Load: 32.7 t ADT: 6,500

KANESVILLE BVLD

Fair

Over: INDIAN CREEK

North Kanesville Crossing, Pottawattamie, IA

Built 1980 Load: 32.7 t ADT: 18,000

WB I-680

Fair

Over: MISSOURI RIVER & CITY ST

IN NORTH OMAHA, Pottawattamie, IA

Built 1975 Load: 32.7 t ADT: 9,150

IA 906

Fair

Over: INDIAN CREEK

3.1 mi. W of I-80, Pottawattamie, IA

Built 1981 Load: 32.7 t ADT: 18,500

KANESVILLE BLVD

Fair

Over: INDIAN CREEK CONDUIT

Kanesville Btwn 6-7 St, Pottawattamie, IA

Built 1983 Load: 32.7 t ADT: 5,933

FM

Fair

Over: STREAM

078152603, Poweshiek, IA

Built 2006 Load: 32.7 t ADT: 10

LOCAL

Fair

Over: STREAM

067301401, Ringgold, IA

Built 1998 Load: 32.7 t ADT: 110

FM

Fair

Over: FLETCHALL CREEK

067302302, Ringgold, IA

Built 1993 Load: 32.7 t ADT: 120

FM

Fair

Over: BRANCH OF LOTTS CREEK

068283202, Ringgold, IA

Built 1993 Load: 32.7 t ADT: 89

P68

Fair

Over: STREAM

068283502, Ringgold, IA

Built 2004 Load: 32.7 t ADT: 60

LOCAL

Fair

Over: STREAM

069302103, Ringgold, IA

Built 1978 Load: 32.7 t ADT: 29

FM

Fair

Over: STREAM

069310301, Ringgold, IA

Built 2005 Load: 32.7 t ADT: 379

LOCAL

Fair

Over: ELK CREEK

070282502, Ringgold, IA

Built 1986 Load: 32.7 t ADT: 45

FM

Fair

Over: SMALL STREAM

067290801, Ringgold, IA

Built 2001 Load: 32.7 t ADT: 270

LOCAL

Fair

Over: NO NAME CREEK

087370901, Sac, IA

Built 1988 Load: 32.7 t ADT: 34

LOCAL

Fair

Over: ELK CREEK

088382802, Sac, IA

Built 1984 Load: 32.7 t ADT: 30

FM

Fair

Over: DD 81

089352101, Sac, IA

Built 1988 Load: 32.7 t ADT: 270

LOCAL

Fair

Over: STREAM

089373402, Sac, IA

Built 1985 Load: 32.7 t ADT: 26

FM

Fair

Over: HALFWAY CREEK

089382801, Sac, IA

Built 1991 Load: 32.7 t ADT: 469

LOCAL

Fair

Over: SMALL STREAM

087381601, Sac, IA

Built 1985 Load: 32.7 t ADT: 15

I-80

Fair

Over: CROW CREEK

2.6 MI. E OF JCT. US 61, Scott, IA

Built 1963 Load: 32.7 t ADT: 30,600

I-80

Fair

Over: DRAINAGE DITCH

3.8 mi. east of jct. I-74, Scott, IA

Built 1963 Load: 32.7 t ADT: 30,800

Showing 6,901-6,950 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.