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

IA 83

Fair

Over: COMPTON CREEK

0.1 mi. W of jct. SR M56, Cass, IA

Built 1936 ADT: 760

BIRCH ST

Fair

Over: GOAT CREEK

000000000, Cherokee, IA

Built 1900 ADT: 501

CEMETARY ACCESS

Fair

Over: STREAM

CHEROKEE MHI, Cherokee, IA

Built 1900

LOCAL

Fair

Over: SHORT CREEK

071273306, Clarke, IA

Built 1964 ADT: 10

OLD US 61

Fair

Over: SILVER CREEK

082E31004, Clinton, IA

Built 1926 ADT: 200

FM 230TH AVE

Fair

Over: MAQUOKETA RIVER

088042902, Delaware, IA

Built 1934 ADT: 108

JADE AVE

Fair

Over: CRANE CREEK

098132202, Howard, IA

Built 1950 ADT: 69

FM

Fair

Over: CREEK

073112806, Jefferson, IA

Built 1957 ADT: 20

IA 15

Fair

Over: LOTTS CREEK

6.3 mi. S of SR A42, Kossuth, IA

Built 1939 ADT: 770

180TH AVE

Fair

Over: DES MOINES RIVER

St. Francis Border Bridge, Lee, IA

Built 1937 ADT: 11

FM

Fair

Over: CEDAR CREEK

074180203, Marion, IA

Built 1957 ADT: 20

LOCAL

Fair

Over: ENGLISH CREEK

075202304, Marion, IA

Built 2002

FM

Fair

Over: NORTH CEDAR CREEK

073191806, Monroe, IA

Built 1983 ADT: 20

FM

Fair

Over: WHITES CREEK

073192506, Monroe, IA

Built 1984 ADT: 26

NB US 75

Fair

Over: DRY CREEK

2.3 mi N of SR C60, Plymouth, IA

Built 1972 ADT: 7,000

NB US 75

Fair

Over: DRY CREEK

3.4 mi. N of jct. SR C60, Plymouth, IA

Built 1972 ADT: 7,000

NB US 75

Fair

Over: DRY CREEK

1.5 mi. S of SR C44, Plymouth, IA

Built 1972 ADT: 7,000

H29 167TH ST

Fair

Over: FOUR MILE CREEK

072280205, Union, IA

Built 1952 ADT: 20

297TH PLACE

Fair

Over: BUFF CREEK

074061203, Washington, IA

Built 1955 ADT: 34

US 65

Fair

Over: CALEB CREEK

1.9 MI. S OF SR J46, Wayne, IA

Built 1947 ADT: 1,240

LOCAL

Fair

Over: MEDICINE CR

067222207, Wayne, IA

Built 1997 ADT: 11

LOCAL

Fair

Over: BACON CREEK TRIB.

088420106, Woodbury, IA

Built 1980 ADT: 20

LOCAL

Fair

Over: PATTERSON CREEK

099063303, Allamakee, IA

Built 1977 Load: 3.2 t ADT: 29

230 STREET

Fair

Over: MINOR DRAINAGE

068431703, Fremont, IA

Built 1940 Load: 3.2 t ADT: 11

LOC 100TH ST

Fair

Over: BUFFALO CR

090080301, Buchanan, IA

Built 1940 Load: 4.5 t ADT: 40

LOCAL

Fair

Over: CREEK

096092104, Winneshiek, IA

Built 1973 Load: 4.5 t ADT: 29

LOCAL SEC RD

Fair

Over: MURRAY CR

094391602, O'Brien, IA

Built 1900 Load: 4.7 t ADT: 15

LOCAL-CLOSED!

Fair

Over: DD 81

095322104, Palo Alto, IA

Built 1882 Load: 4.9 t ADT: 46

LOCAL

Fair

Over: NORWAY CREEK

082420502, Monona, IA

Built 1983 Load: 5.2 t ADT: 15

WAPSIPINICON SP

Fair

Over: DUTCH CREEK

WAPSIPINICON ST. PK., Jones, IA

Built 1925 Load: 5.4 t

A AVE

Fair

Over: STREAM

094061906, Clayton, IA

Built 1900 Load: 5.5 t ADT: 15

IA 3

Fair

Over: STREAM

1.7 mi W of IA 143, Cherokee, IA

Built 1930 Load: 5.7 t ADT: 2,140

IA 23

Fair

Over: STREAM

1.2 MILES SOUTH OF SR V13, Mahaska, IA

Built 1928 Load: 5.7 t ADT: 2,130

LOCAL ROAD

Fair

Over: CREEK

098072106, Winneshiek, IA

Built 1957 Load: 5.9 t ADT: 39

FM

Fair

Over: FOUR MILE CREEK

073282501, Union, IA

Built 1952 Load: 6.0 t ADT: 50

236TH AVE

Fair

Over: CREEK

096092310, Winneshiek, IA

Built 1900 Load: 6.0 t ADT: 29

QUAIL AVE

Fair

Over: BEEDS CREEK

092203506, Franklin, IA

Built 1953 Load: 6.1 t ADT: 91

LOCAL

Fair

Over: FIELD STREAM

083363602, Carroll, IA

Built 1966 Load: 6.3 t ADT: 11

SS AVE

Fair

Over: BRANCH ENGLISH RIVER

078093104, Iowa, IA

Built 2010 Load: 6.4 t ADT: 11

RUDI PLACE

Fair

Over: DRY RUN CREEK

CITY BRIDGE NO. 28, Black Hawk, IA

Built 1961 Load: 6.7 t ADT: 684

LOCAL ROAD

Fair

Over: CREEK

099101602, Winneshiek, IA

Built 1900 Load: 6.8 t ADT: 33

LOCAL

Fair

Over: STREAM

075320603, Adair, IA

Built 1950 Load: 6.9 t ADT: 21

LOCAL

Fair

Over: WHITE BREAST CK

072262701, Clarke, IA

Built 1975 Load: 6.9 t ADT: 26

PLANT ROAD K

Fair

Over: LONG CREEK

APPROX. 8000' E. OF RD. H, Des Moines, IA

Built 1905 Load: 6.9 t ADT: 10

HUDSON AVE

Fair

Over: STREAM

075430809, Pottawattamie, IA

Built 1991 Load: 6.9 t ADT: 71

DIAMOND RD.

Fair

Over: BELL CR

094070403, Fayette, IA

Built 1960 Load: 7.2 t ADT: 15

LOCAL

Fair

Over: INDIAN CREEK

079361402, Audubon, IA

Built 1958 Load: 7.3 t ADT: 11

LOCAL

Fair

Over: CRANE CREEK

095112402, Chickasaw, IA

Built 1971 Load: 7.3 t ADT: 35

LOCAL RD

Fair

Over: W FORK W NISH

081391203, Shelby, IA

Built 1993 Load: 7.3 t ADT: 30

LOCAL

Fair

Over: TEN MILE CREEK BRANCH

098101401, Winneshiek, IA

Built 1966 Load: 7.3 t ADT: 70

Showing 1,051-1,100 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.