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 210 AVE

Fair

Over: STREAM

089050104, Delaware, IA

Built 1987 Load: 38.9 t ADT: 25

FM

Fair

Over: E FORK DES MOINES RIVER

093290103, Humboldt, IA

Built 1957 Load: 38.9 t ADT: 509

RIVER CAMP RD

Fair

Over: MUD CREEK OVERFLOW

080E21403, Scott, IA

Built 1991 Load: 38.9 t ADT: 290

FM-N-36

Fair

Over: CREEK

079341504, Audubon, IA

Built 1975 Load: 39.0 t ADT: 278

LOCAL

Fair

Over: BR STEIN CK

084122302, Benton, IA

Built 2002 Load: 39.0 t ADT: 15

DOMINO RD

Fair

Over: PINE CREEK

092060206, Clayton, IA

Built 1973 Load: 39.0 t ADT: 619

290TH AVE

Fair

Over: AMES CREEK

081E40502, Clinton, IA

Built 1971 Load: 39.0 t ADT: 1,220

FM 150 ST

Fair

Over: LINDSEY CREEK

090053203, Delaware, IA

Built 1991 Load: 39.0 t ADT: 344

IA 150

Fair

Over: OTTER CREEK

0.2 MI. N OF JCT. IA 56, Fayette, IA

Built 1979 Load: 39.0 t ADT: 5,400

LOCAL

Fair

Over: STREAM

095160402, Floyd, IA

Built 1977 Load: 39.0 t ADT: 29

E53 237TH ST

Fair

Over: RACCOON RIVER

083311109, Greene, IA

Built 1912 Load: 39.0 t ADT: 916

LOCAL

Fair

Over: CREEK

088400802, Ida, IA

Built 1965 Load: 39.0 t ADT: 72

LOCAL

Fair

Over: EAST FORK BATTLE CREEK

088403002, Ida, IA

Built 1965 Load: 39.0 t ADT: 15

FM AM LEGION RD

Fair

Over: SNYDER CREEK

079051703, Johnson, IA

Built 1978 Load: 39.0 t ADT: 1,480

WB US 30

Fair

Over: OVER CIC RR SPUR

0.8 mi. W of E Jct US 218, Linn, IA

Built 1980 Load: 39.0 t ADT: 15,750

MAHAFFEY RD

Fair

Over: DRAINAGE

072433608, Mills, IA

Built 2006 Load: 39.0 t ADT: 100

US 218

Fair

Over: OTTER CREEK

2.6 mi. N of Jct. SR A19, Mitchell, IA

Built 1970 Load: 39.0 t ADT: 2,530

ZINNIA AVE

Fair

Over: SMALL STREAM

100181902, Mitchell, IA

Built 1984 Load: 39.0 t ADT: 167

LOCAL

Fair

Over: CYLINDER CREEK

097313302, Palo Alto, IA

Built 1999 Load: 39.0 t ADT: 21

LOCAL

Fair

Over: PLATTE BRANCH

067331303, Taylor, IA

Built 1984 Load: 39.0 t ADT: 26

FM

Fair

Over: SMALL CREEK

096092305, Winneshiek, IA

Built 2004 Load: 39.0 t ADT: 226

IA 150

Fair

Over: HARTE CREEK

0.2 mi. N OF Jct. SR D16, Buchanan, IA

Built 1984 Load: 39.1 t ADT: 3,890

E TAMA RD

Fair

Over: TRIB TO WOLF CREEK

87-12-34-01-10, Black Hawk, IA

Built 2003 Load: 39.2 t ADT: 570

FM

Fair

Over: LITTLE MAPLE RIVER

090381001, Buena Vista, IA

Built 1974 Load: 39.2 t ADT: 848

MILL CR. EXPWY.

Fair

Over: MILL CREEK

081061107, Clinton, IA

Built 2000 Load: 39.2 t ADT: 7,619

I-35

Fair

Over: STREAM

0.1 mi. N of Jct. IA 3, Franklin, IA

Built 1974 Load: 39.2 t ADT: 15,300

I-35

Fair

Over: TUTTLE CREEK

0.2 MILE N OF JCT US 20, Hamilton, IA

Built 1967 Load: 39.2 t ADT: 16,800

LOCAL

Fair

Over: SMALL STREAM

080092202, Iowa, IA

Built 1985 Load: 39.2 t ADT: 50

NB US 65

Fair

Over: INDIAN CREEK

0.2 MILE S OF JCT IA 117, Jasper, IA

Built 1932 Load: 39.2 t ADT: 11,100

US 34 EB

Fair

Over: CROW CREEK

0.8 mi. E of Jct. Iowa 1, Jefferson, IA

Built 2007 Load: 39.2 t ADT: 2,600

200TH AVENUE

Fair

Over: S FORK WALNUT CREEK

083041302, Jones, IA

Built 1970 Load: 39.2 t ADT: 47

LINN-JONES RD.

Fair

Over: CREEK

086041802, Jones, IA

Built 1985 Load: 39.2 t ADT: 44

530TH AVE

Fair

Over: CYLINDER CREEK

096310802, Palo Alto, IA

Built 1925 Load: 39.2 t ADT: 539

L14

Fair

Over: SMALL STREAM

094432902, Sioux, IA

Built 1954 Load: 39.2 t ADT: 722

IA 9

Fair

Over: DRAINAGE DITCH

0.8 mi. E of E Jct SR R34, Winnebago, IA

Built 1975 Load: 39.2 t ADT: 2,320

LOCAL

Fair

Over: CROOKED CREEK

079020506, Cedar, IA

Built 1996 Load: 39.3 t ADT: 15

GARFIELD RD

Fair

Over: STREAM

080033003, Cedar, IA

Built 1990 Load: 39.3 t ADT: 60

N 40TH ST

Fair

Over: WILLOW CREEK

096210900, Cerro Gordo, IA

Built 1970 Load: 39.3 t ADT: 731

COSGROVE RD

Fair

Over: OLD MANS CREEK

078080210, Johnson, IA

Built 2012 Load: 39.3 t ADT: 61

LINN-JOHNSON RD

Fair

Over: CHERRY CREEK

081080101, Johnson, IA

Built 2001 Load: 39.3 t ADT: 80

IA 5

Fair

Over: NORTH CEDAR CREEK

1.4 MI. S of S.R. G71, Marion, IA

Built 1983 Load: 39.3 t ADT: 3,340

IA 3

Fair

Over: NORTH LIZARD CREEK

1.6 mi. W of jct. IA 15, Pocahontas, IA

Built 1974 Load: 39.3 t ADT: 2,390

MEREDITH DR

Fair

Over: N WALNUT CREEK

O39400540, Polk, IA

Built 1989 Load: 39.3 t ADT: 12,150

FM

Fair

Over: LIME CREEK

086100403, Benton, IA

Built 1990 Load: 39.4 t ADT: 324

FM

Fair

Over: SMALL STREAM

082413304, Crawford, IA

Built 1950 Load: 39.4 t ADT: 358

US 20

Fair

Over: DRAINAGE DITCH

2.3 MI. E OF JCT. IA 38, Delaware, IA

Built 1963 Load: 39.4 t ADT: 9,000

AIRPORT RD

Fair

Over: SOUTH RACCOON RIVER

079310600, Guthrie, IA

Built 1989 Load: 39.4 t ADT: 60

FM

Fair

Over: WALNUT CREEK

072393310, Montgomery, IA

Built 1988 Load: 39.4 t ADT: 153

LOCAL

Fair

Over: DRY CREEK

098071305, Winneshiek, IA

Built 1988 Load: 39.4 t ADT: 33

FM

Fair

Over: STREAM

086453606, Woodbury, IA

Built 1959 Load: 39.4 t ADT: 90

Showing 8,101-8,150 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.