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

Poor

Over: BRANCH WOLF CREEK

086162602, Tama, IA

Built 1945 Load: 13.0 t ADT: 39

LOCAL

Poor

Over: TRIB DESMOINES RIVER

068083004, Van Buren, IA

Built 1966 Load: 13.0 t ADT: 26

LOCAL

Poor

Over: DRAINAGE DITCH

092371202, Buena Vista, IA

Built 1971 Load: 13.1 t ADT: 34

LOCAL

Poor

Over: CROOKED CREEK

079020504, Cedar, IA

Built 1935 Load: 13.1 t ADT: 15

LOCAL

Poor

Over: BIG CREEK

084392205, Crawford, IA

Built 1949 Load: 13.1 t ADT: 30

LOCAL

Poor

Over: FLOOD CREEK

096173001, Floyd, IA

Built 1900 Load: 13.1 t ADT: 49

LOCAL 120TH ST

Poor

Over: LITTLE SIOUX RIVER

081440703, Harrison, IA

Built 1971 Load: 13.1 t ADT: 40

LOCAL

Poor

Over: S LIZARD CREEK DD#22

091332601, Pocahontas, IA

Built 1917 Load: 13.1 t ADT: 11

BIRCH AVENUE

Poor

Over: SIN CREEK

073351706, Adams, IA

Built 1964 Load: 13.2 t ADT: 5

LOCAL - NSHNA V

Poor

Over: INDIAN CREEK

075370803, Cass, IA

Built 1920 Load: 13.2 t ADT: 26

LOCAL

Poor

Over: BR E FK WAPSIPINICON RVR

096131301, Chickasaw, IA

Built 1982 Load: 13.2 t ADT: 59

200TH ST

Poor

Over: VOLGA RIVER

094103401, Fayette, IA

Built 1914 Load: 13.2 t ADT: 33

288TH ST

Poor

Over: MOSQUITO CREEK

078410409, Harrison, IA

Built 1940 Load: 13.2 t ADT: 34

TAYLOR AVE

Poor

Over: PIGEON CREEK

078420102, Harrison, IA

Built 1920 Load: 13.2 t ADT: 40

FM

Poor

Over: BACON CREEK

088410504, Ida, IA

Built 1900 Load: 13.2 t ADT: 199

LOCAL

Poor

Over: MITCHELL CREEK

072100403, Jefferson, IA

Built 1955 Load: 13.2 t ADT: 20

P 64 210TH AVE

Poor

Over: LINDER CREEK

097273302, Kossuth, IA

Built 1947 Load: 13.2 t ADT: 359

TIMBER AVE

Poor

Over: WAPSIPINICON RIVER

100151702, Mitchell, IA

Built 1959 Load: 13.2 t ADT: 29

F AVENUE

Poor

Over: STREAM

068391302, Page, IA

Built 1951 Load: 13.2 t ADT: 50

LOCAL

Poor

Over: N LIZARD CREEK

093332201, Pocahontas, IA

Built 1921 Load: 13.2 t ADT: 20

210TH STREET

Poor

Over: PIGEON CREEK

077432708, Pottawattamie, IA

Built 1952 Load: 13.2 t ADT: 40

LOCAL

Poor

Over: SOUTH ENGLISH RIVER

078143502, Poweshiek, IA

Built 1974 Load: 13.2 t ADT: 40

LOCAL

Poor

Over: SPRING CREEK

073130803, Wapello, IA

Built 1920 Load: 13.2 t ADT: 26

FM

Poor

Over: SOUTH CHARITON RIVER

069223202, Wayne, IA

Built 1918 Load: 13.2 t ADT: 40

LOCAL ROAD

Poor

Over: CREEK

100073303, Winneshiek, IA

Built 1900 Load: 13.2 t ADT: 26

240TH STREET

Poor

Over: STREAM

071351303, Adams, IA

Built 1979 Load: 13.3 t ADT: 79

20TH ST.

Poor

Over: E BUFFALO CREEK

091083301, Fayette, IA

Built 1957 Load: 13.3 t ADT: 25

20TH ST.

Poor

Over: DRY RUN TO E BUFFALO CR

091083401, Fayette, IA

Built 1957 Load: 13.3 t ADT: 20

LOCAL

Poor

Over: CREEK

095152302, Floyd, IA

Built 1924 Load: 13.3 t ADT: 39

LOCAL

Poor

Over: FLOOD CREEK

097183302, Floyd, IA

Built 1913 Load: 13.3 t ADT: 44

240TH STREET

Poor

Over: PIGEON CREEK

079411403, Harrison, IA

Built 1967 Load: 13.3 t ADT: 15

LOCAL

Poor

Over: CHERRY CREEK

080190502, Jasper, IA

Built 1937 Load: 13.3 t ADT: 30

WAPSIPINICON SP

Poor

Over: DUTCH CREEK

WAPSIPINICON ST. PARK, Jones, IA

Built 1925 Load: 13.3 t

FM

Poor

Over: CREEK

080222605, Polk, IA

Built 1951 Load: 13.3 t ADT: 229

LOCAL

Poor

Over: NORTH WALNUT CREEK

081140302, Poweshiek, IA

Built 1979 Load: 13.3 t ADT: 30

LOCAL

Poor

Over: TRIB DES MOINES R

069100215, Van Buren, IA

Built 1912 Load: 13.3 t ADT: 26

FM

Poor

Over: NORTH BEAR CREEK

100072506, Winneshiek, IA

Built 1952 Load: 13.3 t ADT: 137

LOCAL

Poor

Over: SMALL STREAM

085401401, Crawford, IA

Built 1962 Load: 13.4 t ADT: 21

LOCAL

Poor

Over: CROOKED CREEK

073052602, Henry, IA

Built 1956 Load: 13.4 t ADT: 35

58TH ST

Poor

Over: CREEK

084E51405, Jackson, IA

Built 1940 Load: 13.4 t ADT: 11

LOCAL

Poor

Over: SUGAR CR

069060602, Lee, IA

Built 1963 Load: 13.4 t ADT: 80

140TH ST

Poor

Over: DRAINAGE

093432901, Plymouth, IA

Built 1961 Load: 13.4 t ADT: 30

LOCAL

Poor

Over: RACCOON RIVER

089362503, Sac, IA

Built 1930 Load: 13.4 t ADT: 26

LOCAL

Poor

Over: MIDDLE RIVER

075323301, Adair, IA

Built 1950 Load: 13.5 t ADT: 30

FM

Poor

Over: CRANE CREEK

096121102, Chickasaw, IA

Built 1960 Load: 13.5 t ADT: 69

SOUTH AVE

Poor

Over: IOWA RIVER

089201708, Hardin, IA

Built 1957 Load: 13.5 t ADT: 1,041

325TH ST

Poor

Over: PIGEON CREEK

078422703, Harrison, IA

Built 1960 Load: 13.5 t ADT: 11

LOCAL ROAD

Poor

Over: LYNN CREEK

072061805, Henry, IA

Built 1975 Load: 13.5 t ADT: 16

MAIER AVE

Poor

Over: PICAYUNE CR

078061904, Johnson, IA

Built 1915 Load: 13.5 t ADT: 10

LOC 20TH AVE

Poor

Over: E FORK DES MOINES RIVER

098300504, Kossuth, IA

Built 1973 Load: 13.5 t ADT: 359

Showing 17,051-17,100 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.