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

Fair

Over: CREEK

095152002, Floyd, IA

Built 1985 Load: 32.7 t ADT: 33

LOCAL

Fair

Over: FLOOD CREEK

095170404, Floyd, IA

Built 2006 Load: 32.7 t ADT: 15

FM

Fair

Over: DRY RUN

096151001, Floyd, IA

Built 1979 Load: 32.7 t ADT: 638

LOCAL

Fair

Over: STEWART CREEK

096161902, Floyd, IA

Built 2008 Load: 32.7 t ADT: 49

LOCAL

Fair

Over: CREEK

096182701, Floyd, IA

Built 1977 Load: 32.7 t ADT: 20

FM JONQUIL AVE

Fair

Over: DRAINAGE DITCH NO 6

090211002, Franklin, IA

Built 1980 Load: 32.7 t ADT: 10

RAVEN AVE

Fair

Over: SMALL STREAM

091202502, Franklin, IA

Built 1995 Load: 32.7 t ADT: 26

MALLARD AVE

Fair

Over: MAYNES CREEK

091203002, Franklin, IA

Built 2005 Load: 32.7 t ADT: 1,277

KILLDEER AVE

Fair

Over: MAYNES CREEK

091212302, Franklin, IA

Built 1984 Load: 32.7 t ADT: 21

HEATHER AVE

Fair

Over: BUFFALO CREEK

092210502, Franklin, IA

Built 1987 Load: 32.7 t ADT: 21

LARK AVE

Fair

Over: BEEDS CREEK

092212502, Franklin, IA

Built 1968 Load: 32.7 t ADT: 91

YARROW AVE

Fair

Over: BOYLAN CREEK

093191302, Franklin, IA

Built 1978 Load: 32.7 t ADT: 10

HEATHER AVE

Fair

Over: SMALL STREAM

093210802, Franklin, IA

Built 1990 Load: 32.7 t ADT: 30

LOCAL

Fair

Over: FLAY CREEK

093220301, Franklin, IA

Built 1989 Load: 32.7 t ADT: 26

FM 45TH STREET

Fair

Over: FIELD DRAW

090222205, Franklin, IA

Built 1981 Load: 32.7 t ADT: 226

SR 160 TH ST

Fair

Over: DRAINAGE

092222503, Franklin, IA

Built 1971 Load: 32.7 t ADT: 62

NETTLE AVE

Fair

Over: WATERWAY

091201702, Franklin, IA

Built 1960 Load: 32.7 t ADT: 26

1ST ST NW

Fair

Over: BEEDS CREEK

0000000000, Franklin, IA

Built 1920 Load: 32.7 t ADT: 2,468

300 STREET

Fair

Over: HIGH CREEK

067402001, Fremont, IA

Built 1988 Load: 32.7 t ADT: 11

310 STREET

Fair

Over: ROCK CREEK

067402601, Fremont, IA

Built 1962 Load: 32.7 t ADT: 358

200 STREET

Fair

Over: DRAINAGE DITCH

069432701, Fremont, IA

Built 1978 Load: 32.7 t ADT: 79

210 STREET

Fair

Over: MULE SLOUGH

069433301, Fremont, IA

Built 1976 Load: 32.7 t ADT: 72

300 AVENUE

Fair

Over: DRISCALL CREEK

070410704, Fremont, IA

Built 1987 Load: 32.7 t ADT: 15

300 AVENUE

Fair

Over: CAMP CREEK

070413102, Fremont, IA

Built 1979 Load: 32.7 t ADT: 51

BLUFF ROAD

Fair

Over: SMALL STREAM

070431108, Fremont, IA

Built 1986 Load: 32.7 t ADT: 139

BLUFF ROAD

Fair

Over: SMALL STREAM

070431406, Fremont, IA

Built 1986 Load: 32.7 t ADT: 139

W AVE

Fair

Over: SNAKE CREEK

082292302, Greene, IA

Built 1984 Load: 32.7 t ADT: 35

320 TH

Fair

Over: SNAKE CREEK

082292601, Greene, IA

Built 1981 Load: 32.7 t ADT: 5

337 TH

Fair

Over: BOWERS RUN

082293603, Greene, IA

Built 1995 Load: 32.7 t ADT: 40

R AVE / P30

Fair

Over: SMALL STREAM

082301204, Greene, IA

Built 1973 Load: 32.7 t ADT: 190

L AVE / P18

Fair

Over: GREENBRIER CREEK

082311302, Greene, IA

Built 1991 Load: 32.7 t ADT: 26

J AVE / P14

Fair

Over: CREEK

082312702, Greene, IA

Built 1972 Load: 32.7 t ADT: 139

330 TH / E63

Fair

Over: MOSQUITO CREEK

082313401, Greene, IA

Built 1978 Load: 32.7 t ADT: 199

270 TH

Fair

Over: GREENBRIER CREEK

083313201, Greene, IA

Built 1983 Load: 32.7 t ADT: 45

205 TH/IMPERIAL

Fair

Over: STREAM

084312803, Greene, IA

Built 1958 Load: 32.7 t ADT: 51

A AVE / N58

Fair

Over: CREEK

084323002, Greene, IA

Built 1984 Load: 32.7 t ADT: 131

110 TH

Fair

Over: EAST BUTTRICKS CREEK

085290901, Greene, IA

Built 1983 Load: 32.7 t ADT: 15

130 TH

Fair

Over: DRAINAGE DITCH #110

085302001, Greene, IA

Built 1996 Load: 32.7 t ADT: 528

150 TH

Fair

Over: STREAM

085303101, Greene, IA

Built 1965 Load: 32.7 t ADT: 26

KIRKWOOD AVE

Fair

Over: HARDIN CREEK

085310206, Greene, IA

Built 1948 Load: 32.7 t ADT: 35

E18

Fair

Over: SMALL STREAM

085302401, Greene, IA

Built 1985 Load: 32.7 t ADT: 597

D19 160TH ST

Fair

Over: BR N BLACKHAWK CREEK

088150303, Grundy, IA

Built 1985 Load: 32.7 t ADT: 786

F AVE

Fair

Over: SMALL NATURAL STREAM

087181102, Grundy, IA

Built 1969 Load: 32.7 t ADT: 1,169

FM

Fair

Over: BR WOLF CREEK

086170102, Grundy, IA

Built 1977 Load: 32.7 t ADT: 69

LOCAL ROAD

Fair

Over: DOWD CREEK

086180901, Grundy, IA

Built 1978 Load: 32.7 t ADT: 49

LOCAL

Fair

Over: WOLF CREEK

086181001, Grundy, IA

Built 1975 Load: 32.7 t ADT: 49

LOCAL

Fair

Over: FORK OF DOWD CREEK

086181603, Grundy, IA

Built 1985 Load: 32.7 t ADT: 49

LOCAL

Fair

Over: BRANCH BLACK HAWK CREEK

087161802, Grundy, IA

Built 1994 Load: 32.7 t ADT: 69

FM

Fair

Over: MUNNS CREEK

087162202, Grundy, IA

Built 1994 Load: 32.7 t ADT: 628

FM

Fair

Over: BR BLACKHAWK CK

088152002, Grundy, IA

Built 1977 Load: 32.7 t ADT: 1,051

Showing 6,551-6,600 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.