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

Fair

Over: CREEK

079343102, Audubon, IA

Built 1959 Load: 16.6 t ADT: 34

P AVE

Fair

Over: SMALL STREAM

083412201, Crawford, IA

Built 2000 Load: 16.6 t ADT: 11

FM

Fair

Over: CLEAR CREEK

075101507, Keokuk, IA

Built 1994 Load: 16.6 t ADT: 60

LOCAL

Fair

Over: STREAM

076120501, Keokuk, IA

Built 1990 Load: 16.6 t ADT: 26

W25

Fair

Over: VOLGA RIVER

093093502, Fayette, IA

Built 1950 Load: 16.7 t ADT: 471

LOCAL RD

Fair

Over: STREAM

100403402, Osceola, IA

Built 1945 Load: 16.7 t ADT: 21

120TH STREET

Fair

Over: WEST TARKIO RIVER

070381401, Page, IA

Built 1979 Load: 16.7 t ADT: 20

US 30 WB TO I35 NB

Fair

Over: DRAINAGE DITCH

AT JUNCTION US 30, Story, IA

Built 1964 Load: 16.7 t ADT: 1,780

LOCAL

Fair

Over: STREAM

072312101, Union, IA

Built 1981 Load: 16.7 t ADT: 123

US 34

Fair

Over: E NODAWAY RIVER & RR

0.8 MI. W OF JCT.148, Adams, IA

Built 1964 Load: 16.8 t ADT: 2,970

VINCENT AVE

Fair

Over: DRY CREEK

087072704, Buchanan, IA

Built 1960 Load: 16.8 t ADT: 11

LOCAL

Fair

Over: BIG CEDAR CR D D 181

089343202, Calhoun, IA

Built 1961 Load: 16.8 t ADT: 15

LOCAL - YORK

Fair

Over: THREE MILE CREEK

074363503, Cass, IA

Built 1982 Load: 16.8 t ADT: 72

LOCAL - 680TH

Fair

Over: CREEK

075352804, Cass, IA

Built 1981 Load: 16.8 t ADT: 11

LOCAL

Fair

Over: COON CREEK

083393505, Crawford, IA

Built 1996 Load: 16.8 t ADT: 51

LOCAL

Fair

Over: CREEK

089022401, Dubuque, IA

Built 1900 Load: 16.8 t ADT: 70

WREN AVE

Fair

Over: HARTGRAVES CR

092192604, Franklin, IA

Built 1977 Load: 16.8 t ADT: 62

110 TH / E13

Fair

Over: CEDAR CREEK

085321101, Greene, IA

Built 1959 Load: 16.8 t ADT: 110

LOCAL

Fair

Over: SMALL CREEK

084E61701, Jackson, IA

Built 1958 Load: 16.8 t ADT: 26

400TH ST

Fair

Over: WAPSINONOE CREEK

079052301, Johnson, IA

Built 1977 Load: 16.8 t ADT: 80

FM

Fair

Over: SUGAR CREEK

067050906, Lee, IA

Built 1974 Load: 16.8 t ADT: 25

LOCAL

Fair

Over: SUGAR CREEK

069062606, Lee, IA

Built 1952 Load: 16.8 t ADT: 50

LOCAL ROAD

Fair

Over: ASHBY CREEK

071382901, Montgomery, IA

Built 1975 Load: 16.8 t ADT: 11

LOCAL

Fair

Over: MINOR DRAINAGE

073360609, Montgomery, IA

Built 1966 Load: 16.8 t ADT: 20

TEAK AVENUE

Fair

Over: BUCHANAN CREEK

067362004, Page, IA

Built 1979 Load: 16.8 t ADT: 89

290TH STREET

Fair

Over: WEST TARKIO CREEK

067391601, Page, IA

Built 1984 Load: 16.8 t ADT: 40

260TH STREET

Fair

Over: EAST NODAWAY RIVER

068363201, Page, IA

Built 1985 Load: 16.8 t ADT: 60

FIR AVE

Fair

Over: BULL RUN

092472802, Plymouth, IA

Built 1949 Load: 16.8 t ADT: 26

FM

Fair

Over: KEG CREEK

074422801, Pottawattamie, IA

Built 1959 Load: 16.8 t ADT: 110

LOCAL

Fair

Over: STREAM

067280603, Ringgold, IA

Built 1954 Load: 16.8 t ADT: 15

LOCAL

Fair

Over: PIGEON CREEK

802040, Shelby, IA

Built 1950 Load: 16.8 t ADT: 62

LOCAL

Fair

Over: CREEK

070092603, Van Buren, IA

Built 1930 Load: 16.8 t ADT: 16

LOCAL ROAD

Fair

Over: CREEK

100092603, Winneshiek, IA

Built 1967 Load: 16.8 t ADT: 49

LOCAL

Fair

Over: E NISHNABOTNA RIVER

078363605, Audubon, IA

Built 1984 Load: 16.9 t ADT: 30

FM F-32

Fair

Over: CREEK

080360807, Audubon, IA

Built 1965 Load: 16.9 t ADT: 110

FM LAPORTE RD

Fair

Over: MUD CREEK

087101909, Buchanan, IA

Built 1967 Load: 16.9 t ADT: 314

FM

Fair

Over: BR NORTH RACCOON RIVER

081290504, Dallas, IA

Built 1934 Load: 16.9 t ADT: 20

LOCAL

Fair

Over: ELK CREEK

069272803, Decatur, IA

Built 1957 Load: 16.9 t ADT: 62

345TH STREET

Fair

Over: STREAM

075412306, Pottawattamie, IA

Built 1998 Load: 16.9 t ADT: 15

LOCAL

Fair

Over: CREEK

068320301, Taylor, IA

Built 1951 Load: 16.9 t ADT: 5

265TH STREET

Fair

Over: WILLOW CREEK

071332803, Adams, IA

Built 1964 Load: 17.0 t ADT: 26

FM

Fair

Over: BRANCH YELLOW RIVER

096042606, Allamakee, IA

Built 1958 Load: 17.0 t ADT: 69

FM

Fair

Over: BRANCH WILLIAMS CREEK

096051706, Allamakee, IA

Built 1958 Load: 17.0 t ADT: 589

FM

Fair

Over: BRANCH WILLIAMS CREEK

096051704, Allamakee, IA

Built 1958 Load: 17.0 t ADT: 589

FM

Fair

Over: BRANCH WILLIAMS CREEK

096051904, Allamakee, IA

Built 1958 Load: 17.0 t ADT: 511

FM

Fair

Over: BRANCH WILLIAMS CREEK

096051905, Allamakee, IA

Built 1958 Load: 17.0 t ADT: 589

FM

Fair

Over: BRANCH YELLOW RIVER

096060304, Allamakee, IA

Built 1959 Load: 17.0 t ADT: 422

FM

Fair

Over: YELLOW RIVER

096060505, Allamakee, IA

Built 1962 Load: 17.0 t ADT: 1,375

LOCAL RD

Fair

Over: HICKORY CREEK

096063504, Allamakee, IA

Built 1900 Load: 17.0 t ADT: 49

FM

Fair

Over: BRANCH YELLOW RIVER

097061104, Allamakee, IA

Built 1959 Load: 17.0 t ADT: 422

Showing 1,701-1,750 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.