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

WATER STREET NE

Fair

Over: WEST HOOSIER CREEK

0810703, Johnson, IA

Built 2010 Load: 22.3 t ADT: 49

IA 38

Fair

Over: SIBLES CREEK

0.3 MI. S OF SR E53, Jones, IA

Built 1951 Load: 22.3 t ADT: 1,080

IA 38

Fair

Over: SIBLES CREEK

1.8 MI S OF S JCT SR E-45, Jones, IA

Built 1953 Load: 22.3 t ADT: 1,080

LOCAL

Fair

Over: GERMAN CREEK

076111401, Keokuk, IA

Built 1979 Load: 22.3 t ADT: 40

FM

Fair

Over: GERMAN CREEK

076112701, Keokuk, IA

Built 1979 Load: 22.3 t ADT: 40

LOC 70TH AVE

Fair

Over: LOTTS CREEK

094293102, Kossuth, IA

Built 1977 Load: 22.3 t ADT: 26

LOC 80TH AVE

Fair

Over: LOTTS CREEK

094293204, Kossuth, IA

Built 1978 Load: 22.3 t ADT: 11

LOC 120TH ST

Fair

Over: LOTTS CREEK

094302601, Kossuth, IA

Built 1975 Load: 22.3 t ADT: 26

LOC 110TH ST

Fair

Over: LOTTS CREEK

094303603, Kossuth, IA

Built 1974 Load: 22.3 t ADT: 41

LOC 70TH AVE

Fair

Over: BLACK CAT CREEK

096290602, Kossuth, IA

Built 1983 Load: 22.3 t ADT: 46

FM 280TH ST

Fair

Over: BLACK CAT CREEK

096300101, Kossuth, IA

Built 1980 Load: 22.3 t ADT: 15

LOC 290TH ST

Fair

Over: BLACK CAT CREEK

097303501, Kossuth, IA

Built 1975 Load: 22.3 t ADT: 41

LOC 360TH ST

Fair

Over: E FORK DES MOINES RIVER

098292203, Kossuth, IA

Built 1976 Load: 22.3 t ADT: 62

FM

Fair

Over: SUGAR CREEK

065050704, Lee, IA

Built 1967 Load: 22.3 t ADT: 600

FM

Fair

Over: LITTLE WHITEBREAST CREEK

072212205, Lucas, IA

Built 1958 Load: 22.3 t ADT: 230

FM

Fair

Over: SOUTH OTTER CREEK

072230404, Lucas, IA

Built 1976 Load: 22.3 t ADT: 40

FM

Fair

Over: CARRUTHERS CREEK

073201203, Lucas, IA

Built 1984 Load: 22.3 t ADT: 50

LOCAL

Fair

Over: NORTH CEDAR CREEK

073202706, Lucas, IA

Built 1973 Load: 22.3 t ADT: 30

LOCAL

Fair

Over: OTTER CREEK

073230802, Lucas, IA

Built 1964 Load: 22.3 t ADT: 20

LOCAL

Fair

Over: N FORK CLANTON CREEK

074270706, Madison, IA

Built 1985 Load: 22.3 t ADT: 100

LOCAL RD

Fair

Over: NORTH RIVER

076270201, Madison, IA

Built 1981 Load: 22.3 t ADT: 110

FM

Fair

Over: CEDAR CREEK

076272304, Madison, IA

Built 1962 Load: 22.3 t ADT: 89

FM

Fair

Over: BADGER CREEK

077271104, Madison, IA

Built 1960 Load: 22.3 t ADT: 131

LOCAL RD

Fair

Over: NORTH RIVER

077272802, Madison, IA

Built 1975 Load: 22.3 t ADT: 131

LOCAL

Fair

Over: ENGLISH CREEK

074200903, Marion, IA

Built 1977 Load: 22.3 t ADT: 73

FM

Fair

Over: STREAM

075182547, Marion, IA

Built 1958 Load: 22.3 t ADT: 100

FM

Fair

Over: LOCAL STREAM

071163204, Monroe, IA

Built 1963 Load: 22.3 t ADT: 30

FM

Fair

Over: STREAM

071163207, Monroe, IA

Built 1963 Load: 22.3 t ADT: 40

FM

Fair

Over: GRAYS CREEK

073160106, Monroe, IA

Built 1982 Load: 22.3 t ADT: 120

LOCAL

Fair

Over: LITTLE TARKIO

071382301, Montgomery, IA

Built 1967 Load: 22.3 t ADT: 50

LOCAL

Fair

Over: TARKIO CR

072372101, Montgomery, IA

Built 1974 Load: 22.3 t ADT: 26

LOCAL

Fair

Over: INDIAN CREEK

072391804, Montgomery, IA

Built 1968 Load: 22.3 t ADT: 20

FM

Fair

Over: NISHNABOTNA TRIB

073382603, Montgomery, IA

Built 1959 Load: 22.3 t ADT: 120

LOCAL

Fair

Over: CRABAPPLE CREEK

073391302, Montgomery, IA

Built 1967 Load: 22.3 t ADT: 34

V AVENUE

Fair

Over: STREAM

069363504, Page, IA

Built 1982 Load: 22.3 t ADT: 40

QUINCE AVENUE

Fair

Over: STREAM

069371204, Page, IA

Built 1977 Load: 22.3 t ADT: 20

LOCAL

Fair

Over: CLEAR CREEK

092433002, Plymouth, IA

Built 1959 Load: 22.3 t ADT: 399

IA 15

Fair

Over: BEAVER CREEK

2.9 mi. S of SR C15, Pocahontas, IA

Built 1957 Load: 22.3 t ADT: 250

LOCAL

Fair

Over: BIG CEDAR CK

090341402, Pocahontas, IA

Built 1973 Load: 22.3 t ADT: 40

FM

Fair

Over: W FORK DES MOINES RIVER

093310102, Pocahontas, IA

Built 1967 Load: 22.3 t ADT: 40

LOCAL

Fair

Over: SUGAR CREEK

078160701, Poweshiek, IA

Built 1984 Load: 22.3 t ADT: 26

LOCAL

Fair

Over: NORTH ENGLISH RIVER

079141302, Poweshiek, IA

Built 1985 Load: 22.3 t ADT: 20

LOCAL

Fair

Over: NORTH ENGLISH RIVER

079142104, Poweshiek, IA

Built 1984 Load: 22.3 t ADT: 40

FM

Fair

Over: BIG BEAR CREEK

080151202, Poweshiek, IA

Built 1983 Load: 22.3 t ADT: 100

FM

Fair

Over: WALNUT CREEK

081130806, Poweshiek, IA

Built 1984 Load: 22.3 t ADT: 45

FM

Fair

Over: WALNUT CREEK

081131004, Poweshiek, IA

Built 1962 Load: 22.3 t ADT: 60

LOCAL

Fair

Over: LOTTS CREEK

068281901, Ringgold, IA

Built 1978 Load: 22.3 t ADT: 15

LOCAL

Fair

Over: RACCOON RIVER

089353103, Sac, IA

Built 1975 Load: 22.3 t ADT: 26

47TH AVE

Fair

Over: MUD CREEK

079E11104, Scott, IA

Built 1965 Load: 22.3 t ADT: 30

170TH ST

Fair

Over: DRAINAGE DITCH 36

084221201, Story, IA

Built 1969 Load: 22.3 t ADT: 34

Showing 3,301-3,350 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.