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

150TH

Fair

Over: COLD WATER CREEK

094190701, Cerro Gordo, IA

Built 1971 Load: 22.5 t ADT: 609

KILLDEER

Fair

Over: W FORK BEAVER DAM CREEK

094211402, Cerro Gordo, IA

Built 1926 Load: 22.5 t ADT: 41

220TH

Fair

Over: BAD LANDS DRAW

095190303, Cerro Gordo, IA

Built 1978 Load: 22.5 t ADT: 11

170TH

Fair

Over: E BR BEAVER DAM CREEK

095203301, Cerro Gordo, IA

Built 1973 Load: 22.5 t ADT: 69

NETTLE AVE

Fair

Over: CHESALEA CREEK

096202002, Cerro Gordo, IA

Built 1972 Load: 22.5 t ADT: 1,394

GROUSE

Fair

Over: WILLOW CREEK

096210602, Cerro Gordo, IA

Built 1968 Load: 22.5 t ADT: 884

LARK

Fair

Over: WILLOW CREEK

096211208, Cerro Gordo, IA

Built 1970 Load: 22.5 t ADT: 1,061

LARK

Fair

Over: CRANE CREEK

096211302, Cerro Gordo, IA

Built 1971 Load: 22.5 t ADT: 1,061

LOCAL

Fair

Over: TWO MILE CREEK

094142301, Chickasaw, IA

Built 1996 Load: 22.5 t ADT: 73

BEAR RD

Fair

Over: ENSIGN HOLLOW

092062806, Clayton, IA

Built 1976 Load: 22.5 t ADT: 39

220TH ST

Fair

Over: BUCK CREEK

093030503, Clayton, IA

Built 1978 Load: 22.5 t ADT: 15

232ND ST

Fair

Over: BUCK CREEK

093030903, Clayton, IA

Built 1973 Load: 22.5 t ADT: 113

172ND ST

Fair

Over: SMALL STREAM

094050700, Clayton, IA

Built 2016 Load: 22.5 t ADT: 26

IA 3

Fair

Over: STREAM

7.1 MI. W OF JCT. IA 187, Fayette, IA

Built 1959 Load: 22.5 t ADT: 1,400

110 TH

Fair

Over: HARDIN CREEK

085311101, Greene, IA

Built 1978 Load: 22.5 t ADT: 100

LOCAL

Fair

Over: LONG BRANCH

078302405, Guthrie, IA

Built 1974 Load: 22.5 t ADT: 349

FM

Fair

Over: DM RIVER

091281904, Humboldt, IA

Built 1961 Load: 22.5 t ADT: 559

LOCAL

Fair

Over: DRAINAGE DITCH

091292802, Humboldt, IA

Built 1955 Load: 22.5 t ADT: 11

LOCAL

Fair

Over: DD

093272404, Humboldt, IA

Built 1956 Load: 22.5 t ADT: 15

WAPSIE RD

Fair

Over: STREAM

080052106, Johnson, IA

Built 1965 Load: 22.5 t ADT: 102

LOCAL RD

Fair

Over: DRAINAGE

075292801, Madison, IA

Built 1959 Load: 22.5 t ADT: 11

LOCAL

Fair

Over: SMALL

077280204, Madison, IA

Built 1942 Load: 22.5 t ADT: 50

FM

Fair

Over: WATERMAN CREEK

094390314, O'Brien, IA

Built 1961 Load: 22.5 t ADT: 210

280TH ST

Fair

Over: DEER CREEK

090430501, Plymouth, IA

Built 1956 Load: 22.5 t ADT: 11

JUNIPER AVE

Fair

Over: DRAINAGE

092461402, Plymouth, IA

Built 1900 Load: 22.5 t ADT: 20

FM

Fair

Over: W NISHNABOTNA

074402110, Pottawattamie, IA

Built 1960 Load: 22.5 t ADT: 417

320TH STREET

Fair

Over: LITTLE SILVER CREEK

076412802, Pottawattamie, IA

Built 1940 Load: 22.5 t ADT: 15

2ND STREET

Fair

Over: INDIAN CREEK

000000000, Pottawattamie, IA

Built 1972 Load: 22.5 t ADT: 2,806

200TH AVE

Fair

Over: RIGHT SIDE DITCH

0.7 mi. E of E Jct SR S23, Warren, IA

Built 1973 Load: 22.5 t ADT: 10

US 69

Fair

Over: PIKE RUN CREEK

0.5 mi N of N jct IA 9, Winnebago, IA

Built 1968 Load: 22.5 t ADT: 1,650

VINE

Fair

Over: DEER CREEK

100192702, Worth, IA

Built 1948 Load: 22.5 t ADT: 59

FM

Fair

Over: MIDDLE RIVER

076302609, Adair, IA

Built 1900 Load: 22.6 t ADT: 20

MAIN STREET

Fair

Over: WALNUT CREEK

069181704, Appanoose, IA

Built 1999 Load: 22.6 t ADT: 226

LOCAL

Fair

Over: SPRING BRANCH CREEK

083341504, Carroll, IA

Built 1981 Load: 22.6 t ADT: 60

LOCAL

Fair

Over: MIDDLE RACCOON RIVER

084360101, Carroll, IA

Built 1974 Load: 22.6 t ADT: 20

LOCAL

Fair

Over: BEAVER CREEK

085401101, Crawford, IA

Built 2006 Load: 22.6 t ADT: 5

FM

Fair

Over: WELDON RIVER

067242201, Decatur, IA

Built 1951 Load: 22.6 t ADT: 170

FM

Fair

Over: FLOOD CREEK

094163402, Floyd, IA

Built 1964 Load: 22.6 t ADT: 187

LOCAL 60TH ST

Fair

Over: NORTH BEAVER CREEK

090191601, Franklin, IA

Built 1967 Load: 22.6 t ADT: 26

LOCAL 40TH ST

Fair

Over: SMALL STREAM

090192801, Franklin, IA

Built 1971 Load: 22.6 t ADT: 30

LOCAL TULIP AVE

Fair

Over: SMALL STREAM

090192804, Franklin, IA

Built 1969 Load: 22.6 t ADT: 47

FM

Fair

Over: SOUTH RACCOON RIVER

079312609, Guthrie, IA

Built 1969 Load: 22.6 t ADT: 219

LOCAL

Fair

Over: GREENBRIER CREEK

081300104, Guthrie, IA

Built 1982 Load: 22.6 t ADT: 29

FM

Fair

Over: BRUSHY CREEK

081332202, Guthrie, IA

Built 1972 Load: 22.6 t ADT: 71

1740 RAKE AVE

Fair

Over: EAST BRANCH IA RIVER

095242502, Hancock, IA

Built 1985 Load: 22.6 t ADT: 35

FM 1870 225 ST

Fair

Over: EAST IOWA RIVER

096243603, Hancock, IA

Built 1972 Load: 22.6 t ADT: 90

LOCAL

Fair

Over: SO.FK. IOWA RIVER

089222801, Hardin, IA

Built 1990 Load: 22.6 t ADT: 26

FM

Fair

Over: BRANCH SHAWNEE CREEK

073070704, Henry, IA

Built 1973 Load: 22.6 t ADT: 90

FM

Fair

Over: SMALL STREAM

088401104, Ida, IA

Built 1966 Load: 22.6 t ADT: 60

LOCAL

Fair

Over: ALLOWAY CREEK

081183301, Jasper, IA

Built 1994 Load: 22.6 t ADT: 15

Showing 3,401-3,450 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.