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

LOCAL

Structurally Deficient

Over: KEG CREEK

079401303, Shelby, IA

Built 1966 ADT: 11

LOCAL

Structurally Deficient

Over: SM STREAM

095461701, Sioux, IA

Built 1943 ADT: 5

248TH ST

Structurally Deficient

Over: EAST BR INDIAN CREEK

083221403, Story, IA

Built 1936 ADT: 40

LOCAL-DEAD END

Structurally Deficient

Over: SKUNK RIVER

083242405, Story, IA

Built 1876 ADT: 11

190TH ST

Structurally Deficient

Over: SQUAW CREEK

084242001, Story, IA

Built 1900 ADT: 120

FM

Structurally Deficient

Over: SALT CREEK

082132503, Tama, IA

Built 1920 ADT: 157

FM

Structurally Deficient

Over: IOWA RIVER

082141303, Tama, IA

Built 1914 ADT: 39

LOCAL

Structurally Deficient

Over: RICHLAND CREEK

082142302, Tama, IA

Built 1960 ADT: 44

LOCAL

Structurally Deficient

Over: NORTH WALNUT CREEK

082143304, Tama, IA

Built 1915 ADT: 33

LOCAL

Structurally Deficient

Over: SALT CREEK

083130303, Tama, IA

Built 1955 ADT: 44

LOCAL

Structurally Deficient

Over: SALT CREEK

083130303, Tama, IA

Built 1897 ADT: 44

IRR LOCAL

Structurally Deficient

Over: IOWA RIVER OVERFLOW

083161504, Tama, IA

Built 1947 ADT: 216

IRR-LOCAL

Structurally Deficient

Over: IOWA RIVER OVERFLOW

083162204, Tama, IA

Built 1953 ADT: 216

IRR-LOCAL

Structurally Deficient

Over: IOWA RIVER

083162204, Tama, IA

Built 1938 ADT: 216

LOCAL

Structurally Deficient

Over: SOUTH BRANCH SALT CREEK

084132804, Tama, IA

Built 1907 ADT: 26

LOCAL

Structurally Deficient

Over: SALT CREEK

085142802, Tama, IA

Built 2001 ADT: 5

LOCAL

Structurally Deficient

Over: HONEY CREEK

067331701, Taylor, IA

Built 1954 ADT: 11

LOCAL

Structurally Deficient

Over: HONEY CREEK

067331901, Taylor, IA

Built 1962 ADT: 15

FM

Structurally Deficient

Over: HONEY CREEK

067332003, Taylor, IA

Built 1940 ADT: 20

LOCAL

Structurally Deficient

Over: EAST 102 RIVER

067341707, Taylor, IA

Built 1967 ADT: 15

FM

Structurally Deficient

Over: PLATTE BRANCH

068321001, Taylor, IA

Built 1952 ADT: 50

LOCAL

Structurally Deficient

Over: PLATTE BRANCH

068321403, Taylor, IA

Built 1942 ADT: 15

LOCAL

Structurally Deficient

Over: EAST 102 RIVER

068330801, Taylor, IA

Built 1968 ADT: 5

LOCAL

Structurally Deficient

Over: HONEY CREEK

068331103, Taylor, IA

Built 1954 ADT: 5

LOCAL

Structurally Deficient

Over: WEST 102 RIVER

068352203, Taylor, IA

Built 1968 ADT: 15

LOCAL

Structurally Deficient

Over: CREEK

069330504, Taylor, IA

Built 1957 ADT: 5

LOCAL

Structurally Deficient

Over: BRANCH OF EAST 102 RIVER

069332401, Taylor, IA

Built 1953 ADT: 11

FM

Structurally Deficient

Over: DRAINAGE DITCH

069332601, Taylor, IA

Built 1938 ADT: 89

LOCAL

Structurally Deficient

Over: MIDDLE 102 RIVER

069342704, Taylor, IA

Built 1949 ADT: 11

LOCAL

Structurally Deficient

Over: CREEK

069350804, Taylor, IA

Built 1900

LOCAL

Structurally Deficient

Over: CREEK

069351904, Taylor, IA

Built 1953 ADT: 26

ADAMS-TAYLOR ST

Structurally Deficient

Over: W BRANCH 102 RIVER

070330601, Taylor, IA

Built 1920 ADT: 15

LOCAL

Structurally Deficient

Over: CREEK

070330604, Taylor, IA

Built 1952 ADT: 26

LOCAL

Structurally Deficient

Over: MIDDLE 102 RIVER

070341202, Taylor, IA

Built 1972 ADT: 11

LOCAL

Structurally Deficient

Over: WEST 102 RIVER

070341802, Taylor, IA

Built 1962 ADT: 5

LOCAL

Structurally Deficient

Over: UNNAMED STREAM

070342906, Taylor, IA

Built 1970 ADT: 20

LOCAL

Structurally Deficient

Over: W F 102 RIVER

070352601, Taylor, IA

Built 1910 ADT: 15

LOCAL

Structurally Deficient

Over: STREAM

071281905, Union, IA

Built 1900 ADT: 11

LOCAL

Structurally Deficient

Over: STREAM

071282106, Union, IA

Built 1992 ADT: 11

LOCAL

Structurally Deficient

Over: INDIAN CREEK

071290502, Union, IA

Built 1900 ADT: 21

LOCAL

Structurally Deficient

Over: MIDDLE PLATTE RIVER

071311603, Union, IA

Built 1970 ADT: 11

LOCAL

Structurally Deficient

Over: STREAM

072291105, Union, IA

Built 1900 ADT: 21

LOCAL

Structurally Deficient

Over: SMALL STREAM

072302704, Union, IA

Built 1900 ADT: 5

LOC DOGWOOD AVE

Structurally Deficient

Over: SMALL STREAM

072311004, Union, IA

Built 1989 ADT: 35

LOCAL

Structurally Deficient

Over: WEST PLATTE RIVER

072312102, Union, IA

Built 1900 ADT: 15

252ND ST

Structurally Deficient

Over: FOX RIVER

068112203, Van Buren, IA

Built 1885 ADT: 104

LOCAL

Structurally Deficient

Over: CREEK

070102303, Van Buren, IA

Built 1968 ADT: 11

LOCAL

Structurally Deficient

Over: SMALL TRIBUTARY

070102303, Van Buren, IA

Built 1977 ADT: 11

LOCAL

Structurally Deficient

Over: LITTLE SOAP CREEK

071141806, Wapello, IA

Built 1930 ADT: 35

LOCAL

Structurally Deficient

Over: BRUSH CREEK

071143203, Wapello, IA

Built 1930 ADT: 25

Showing 19,751-19,800 of 20,753 bridges

Related

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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.