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 HORTON CREEK

094133102, Chickasaw, IA

Built 1952 Load: 24.6 t ADT: 25

110TH AVE

Poor

Over: WILLOW CREEK

095380502, Clay, IA

Built 1928 Load: 24.6 t ADT: 30

LOC 320 AVE

Poor

Over: SMALL STREAM

087031402, Delaware, IA

Built 1971 Load: 24.6 t ADT: 20

LOCAL ROAD

Poor

Over: BRANCH OF WOLF CREEK

086171803, Grundy, IA

Built 1977 Load: 24.6 t ADT: 44

LOCAL

Poor

Over: CREEK

086200102, Hardin, IA

Built 1977 Load: 24.6 t ADT: 16

FM

Poor

Over: CREEK

073102704, Jefferson, IA

Built 1952 Load: 24.6 t ADT: 50

LOCAL

Poor

Over: STREAM

070303310, Ringgold, IA

Built 1975 Load: 24.6 t ADT: 34

10TH AVE

Poor

Over: CREEK

080E10502, Scott, IA

Built 1951 Load: 24.6 t ADT: 90

LOCAL

Poor

Over: STREAM

067170702, Appanoose, IA

Built 1969 Load: 24.7 t ADT: 11

105TH AVE

Poor

Over: HENRY CREEK

094381804, Clay, IA

Built 1965 Load: 24.7 t ADT: 41

JUNIPER RD.

Poor

Over: DRY BRANCH CREEK

095081002, Fayette, IA

Built 1964 Load: 24.7 t ADT: 403

W SOUTH ST

Poor

Over: MIDDLE RACCOON RIVER

079300504, Guthrie, IA

Built 1965 Load: 24.7 t ADT: 358

LOC 2030 210TH

Poor

Over: GOLLS CREEK

095230801, Hancock, IA

Built 1955 Load: 24.7 t ADT: 62

LOCAL

Poor

Over: SILVER CREEK

088391602, Ida, IA

Built 1983 Load: 24.7 t ADT: 5

FM

Poor

Over: CROOKED CREEK

076102402, Keokuk, IA

Built 1964 Load: 24.7 t ADT: 500

FM

Poor

Over: NELSON CREEK

098483204, Lyon, IA

Built 1966 Load: 24.7 t ADT: 789

FM

Poor

Over: KLONDIKE CREEK

099482105, Lyon, IA

Built 1962 Load: 24.7 t ADT: 1,017

L14

Poor

Over: TURNER CREEK

100441418, Lyon, IA

Built 1964 Load: 24.7 t ADT: 509

216TH STREET

Poor

Over: SNAKE CREEK

069373103, Page, IA

Built 1961 Load: 24.7 t ADT: 71

FM

Poor

Over: STREAM

095322402, Palo Alto, IA

Built 1972 Load: 24.7 t ADT: 60

FM

Poor

Over: PLUM CREEK

070302902, Ringgold, IA

Built 1954 Load: 24.7 t ADT: 120

LOCAL

Poor

Over: BEAVER CREEK

099233501, Winnebago, IA

Built 1976 Load: 24.7 t ADT: 41

LOCAL/KEYSTONE

Poor

Over: CREEK

076342801, Cass, IA

Built 1981 Load: 24.8 t ADT: 26

FM

Poor

Over: LITTLE FLINT RIVER

070031608, Des Moines, IA

Built 1968 Load: 24.8 t ADT: 2,000

LOCAL

Poor

Over: STREAM

076131701, Keokuk, IA

Built 1967 Load: 24.8 t ADT: 50

FM

Poor

Over: CREEK

072170703, Monroe, IA

Built 1963 Load: 24.8 t ADT: 310

LOCAL

Poor

Over: STONY CREEK

080140301, Poweshiek, IA

Built 1971 Load: 24.8 t ADT: 15

E CEDAR-WAPSI RD

Poor

Over: CRANE CREEK

90-12-15-01, Black Hawk, IA

Built 1966 Load: 24.9 t ADT: 2,600

300 ST

Poor

Over: SMALL

090151601, Butler, IA

Built 1979 Load: 24.9 t ADT: 73

LOCAL

Poor

Over: BRUSHY FORK CREEK

082340602, Carroll, IA

Built 1925 Load: 24.9 t ADT: 60

40TH ST

Poor

Over: HUNTER CREEK

091102401, Fayette, IA

Built 1950 Load: 24.9 t ADT: 471

LOCAL

Poor

Over: CONVEY CREEK

079092602, Iowa, IA

Built 1920 Load: 24.9 t ADT: 100

FM

Poor

Over: LITTLE SNIPE CREEK

081191401, Jasper, IA

Built 1927 Load: 24.9 t ADT: 40

LOCAL

Poor

Over: M BR BUCKLEY CREEK

077170301, Mahaska, IA

Built 1950 Load: 24.9 t ADT: 45

FM-TRUMAN AVE

Poor

Over: WALNUT CREEK

077381403, Pottawattamie, IA

Built 1963 Load: 24.9 t ADT: 34

LOCAL

Poor

Over: SOUTH ENGLISH RIVER

078142907, Poweshiek, IA

Built 1984 Load: 24.9 t ADT: 15

LOCAL

Poor

Over: SOUTH BRANCH SALT CREEK

084151303, Tama, IA

Built 1940 Load: 24.9 t ADT: 29

LOCAL ROAD

Poor

Over: TROUT CREEK

097091301, Winneshiek, IA

Built 1915 Load: 24.9 t ADT: 33

LOCAL

Poor

Over: PURGATORY CR.

088322601, Calhoun, IA

Built 1971 Load: 25.0 t ADT: 11

LOCAL

Poor

Over: FIELD STREAM

082333001, Carroll, IA

Built 1957 Load: 25.0 t ADT: 29

EUREKA AVE

Poor

Over: MIDDLE BR WAPSINONOC CR

079041402, Cedar, IA

Built 1895 Load: 25.0 t ADT: 20

LOCAL

Poor

Over: CREEK

085170402, Marshall, IA

Built 1945 Load: 25.0 t ADT: 20

FM K-42

Poor

Over: CARTER CREEK

090460202, Plymouth, IA

Built 1966 Load: 25.0 t ADT: 190

LOCAL

Poor

Over: SUGAR CREEK

079161702, Poweshiek, IA

Built 1980 Load: 25.0 t ADT: 45

LOCAL

Poor

Over: BRANCH SALT CREEK

084142801, Tama, IA

Built 1940 Load: 25.0 t ADT: 39

BRYAN RD

Poor

Over: TRIB TO CEDAR RIVER

87-11-18-01-10, Black Hawk, IA

Built 1951 Load: 25.1 t ADT: 49

FM

Poor

Over: SMALL STREAM

089102201, Buchanan, IA

Built 1957 Load: 25.1 t ADT: 79

FM

Poor

Over: WEST FORK CEDAR RIVER

090150504, Butler, IA

Built 1964 Load: 25.1 t ADT: 874

LOCAL

Poor

Over: CRAB APPLE CREEK

093170202, Butler, IA

Built 1987 Load: 25.1 t ADT: 21

LOCAL

Poor

Over: WAPSIPINICON RIVER

096143501, Chickasaw, IA

Built 1955 Load: 25.1 t ADT: 29

Showing 18,551-18,600 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.