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: DEVIL CREEK

067051003, Lee, IA

Built 1955 Load: 17.2 t ADT: 80

FM

Fair

Over: SUGAR CREEK

067061903, Lee, IA

Built 1954 Load: 17.2 t ADT: 270

385TH

Fair

Over: BURR OAK CREEK

098160903, Mitchell, IA

Built 1954 Load: 17.2 t ADT: 29

ECHO AVE

Fair

Over: ROCK CREEK

098182204, Mitchell, IA

Built 1920 Load: 17.2 t ADT: 44

FM

Fair

Over: STREAM

073160205, Monroe, IA

Built 1958 Load: 17.2 t ADT: 60

LOCAL

Fair

Over: LANGE CREEK

094411902, O'Brien, IA

Built 1954 Load: 17.2 t ADT: 62

X AVENUE

Fair

Over: STREAM

067361302, Page, IA

Built 1961 Load: 17.2 t ADT: 29

X AVENUE

Fair

Over: BUCHANAN CREEK

068363506, Page, IA

Built 1957 Load: 17.2 t ADT: 26

IA 12

Fair

Over: DRAINAGE DITCH

2.0 mi. S of S jct SR K18, Plymouth, IA

Built 1957 Load: 17.2 t ADT: 1,840

LOCAL

Fair

Over: STREAM

088372801, Sac, IA

Built 1960 Load: 17.2 t ADT: 40

FM

Fair

Over: DUTCH BRANCH

078381702, Shelby, IA

Built 1950 Load: 17.2 t ADT: 34

LOCAL

Fair

Over: SMALL STREAM

081392306, Shelby, IA

Built 1951 Load: 17.2 t ADT: 11

720TH AVE

Fair

Over: MIDDLE MINERVA CREEK

085212302, Story, IA

Built 1930 Load: 17.2 t ADT: 11

150TH ST

Fair

Over: HAMILTON-STORY 1 OPEN

085243601, Story, IA

Built 1967 Load: 17.2 t ADT: 110

LOCAL

Fair

Over: RICHLAND CREEK

082141408, Tama, IA

Built 1956 Load: 17.2 t ADT: 78

LOCAL

Fair

Over: W BR 102 RIVER

068350404, Taylor, IA

Built 1960 Load: 17.2 t ADT: 71

LOCAL

Fair

Over: TRIB DESMOINES RIVER

070112207, Van Buren, IA

Built 1964 Load: 17.2 t ADT: 21

320TH ST

Fair

Over: DRAINAGE

087093003, Buchanan, IA

Built 2005 Load: 17.3 t ADT: 30

LOCAL

Fair

Over: FOX RIVER

069153301, Davis, IA

Built 1963 Load: 17.3 t ADT: 30

LOCAL

Fair

Over: STEEL CREEK

069243603, Decatur, IA

Built 1989 Load: 17.3 t ADT: 5

FM

Fair

Over: FLINT RIVER

071042503, Des Moines, IA

Built 1955 Load: 17.3 t ADT: 100

PLANT ROAD I

Fair

Over: LONG CREEK

APPROX. 500' S. OF RD. M, Des Moines, IA

Built 1946 Load: 17.3 t ADT: 15

LOCAL

Fair

Over: DD #7

099321702, Emmet, IA

Built 1970 Load: 17.3 t ADT: 45

SUNSET RD

Fair

Over: LITTLE TURKEY RIVER

095093003, Fayette, IA

Built 1954 Load: 17.3 t ADT: 59

LOCAL

Fair

Over: CREEK

095161702, Floyd, IA

Built 1919 Load: 17.3 t ADT: 29

LOCAL

Fair

Over: SMALL STREAM

095170401, Floyd, IA

Built 1986 Load: 17.3 t ADT: 26

LOCAL

Fair

Over: OLD MAN'S CREEK

079093404, Iowa, IA

Built 1954 Load: 17.3 t ADT: 80

FM

Fair

Over: CLEAR CREEK

081212502, Jasper, IA

Built 1955 Load: 17.3 t ADT: 35

LOCAL

Fair

Over: CREEK

085182302, Marshall, IA

Built 1941 Load: 17.3 t ADT: 11

FM

Fair

Over: WEST 102 RIVER

069352202, Taylor, IA

Built 1946 Load: 17.3 t ADT: 79

FM

Fair

Over: GRAND RIVER

072283301, Union, IA

Built 1957 Load: 17.3 t ADT: 49

FM

Fair

Over: OTTER CREEK

074231703, Warren, IA

Built 1954 Load: 17.3 t ADT: 60

LOCAL

Fair

Over: WEST FORK CROOKED CREEK

076082904, Washington, IA

Built 1956 Load: 17.3 t ADT: 45

LOCAL

Fair

Over: BROOKS CREEK

092381202, Buena Vista, IA

Built 1924 Load: 17.4 t ADT: 11

FM - HIGHLAND

Fair

Over: EAST NISHNABOTNA

076360621, Cass, IA

Built 1959 Load: 17.4 t ADT: 329

FM

Fair

Over: ELK CREEK

082373201, Crawford, IA

Built 1950 Load: 17.4 t ADT: 29

LOCAL

Fair

Over: KING CREEK

084371901, Crawford, IA

Built 1995 Load: 17.4 t ADT: 26

LOCAL

Fair

Over: KILGORE CREEK

068252603, Decatur, IA

Built 2001 Load: 17.4 t ADT: 51

325 AVENUE

Fair

Over: KILPATRICK CREEK

070410904, Fremont, IA

Built 1968 Load: 17.4 t ADT: 5

FM-KEY AVE

Fair

Over: CRANE CREEK

097130204, Howard, IA

Built 1985 Load: 17.4 t ADT: 40

LOCAL

Fair

Over: BIG CEDAR CREEK

072112004, Jefferson, IA

Built 1950 Load: 17.4 t ADT: 40

FM

Fair

Over: LITTLE WHITEBREAST CREEK

073213201, Lucas, IA

Built 1964 Load: 17.4 t ADT: 120

FM

Fair

Over: BRANCH IOWA RIVER

083160903, Tama, IA

Built 1999 Load: 17.4 t ADT: 98

LOCAL

Fair

Over: SMALL STREAM

084140204, Tama, IA

Built 1982 Load: 17.4 t ADT: 59

FM

Fair

Over: WOLF CREEK

086143601, Tama, IA

Built 1953 Load: 17.4 t ADT: 49

LOCAL

Fair

Over: WEST FORK LITTLE SIOUX

088451601, Woodbury, IA

Built 1952 Load: 17.4 t ADT: 80

FM

Fair

Over: BR VILLAGE CREEK

098042006, Allamakee, IA

Built 1988 Load: 17.5 t ADT: 44

LOCAL

Fair

Over: STREAM

067161304, Appanoose, IA

Built 1920 Load: 17.5 t ADT: 11

LOCAL 260TH ST

Fair

Over: BUFFALO CREEK

088072701, Buchanan, IA

Built 1949 Load: 17.5 t ADT: 62

FOREST AVE

Fair

Over: PARMENTAR CREEK

092181202, Butler, IA

Built 2012 Load: 17.5 t ADT: 21

Showing 1,901-1,950 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.