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 - QUEBEC

Poor

Over: SEVEN MILE CREEK

075352903, Cass, IA

Built 1981 Load: 15.6 t ADT: 26

290TH ST

Poor

Over: STREAM

097351505, Clay, IA

Built 1913 Load: 15.6 t ADT: 5

FM

Poor

Over: SOUTH WYACONDAH DITCH

068132010, Davis, IA

Built 1974 Load: 15.6 t ADT: 420

LOCAL

Poor

Over: CREEK

070143404, Davis, IA

Built 1959 Load: 15.6 t ADT: 100

LOCAL

Poor

Over: STREAM

078330505, Guthrie, IA

Built 1957 Load: 15.6 t ADT: 20

FM

Poor

Over: SOUTH RACCOON

080323301, Guthrie, IA

Built 1959 Load: 15.6 t ADT: 50

FM

Poor

Over: SMALL CREEK

086E30802, Jackson, IA

Built 1967 Load: 15.6 t ADT: 60

LOCAL

Poor

Over: PICAYUNE CREEK

069053006, Lee, IA

Built 1934 Load: 15.6 t ADT: 30

GRANITE AVE

Poor

Over: PERRY CREEK

091472202, Plymouth, IA

Built 1952 Load: 15.6 t ADT: 5

FM

Poor

Over: WALNUT CREEK

069181402, Appanoose, IA

Built 1955 Load: 15.7 t ADT: 160

ATLAS RD

Poor

Over: SHELL ROCK RIVER

091141806, Bremer, IA

Built 1959 Load: 15.7 t ADT: 226

YUKON AV

Poor

Over: RIVER

092110102, Bremer, IA

Built 1956 Load: 15.7 t ADT: 39

200TH

Poor

Over: E BR BEAVER DAM CREEK

095201701, Cerro Gordo, IA

Built 1965 Load: 15.7 t ADT: 16

FM

Poor

Over: STREAM

070121704, Davis, IA

Built 1957 Load: 15.7 t ADT: 60

FM

Poor

Over: BEAVER CREEK ,BRANCH

089182001, Grundy, IA

Built 1954 Load: 15.7 t ADT: 79

FM

Poor

Over: CREEK

086402401, Ida, IA

Built 1900 Load: 15.7 t ADT: 26

LOCAL

Poor

Over: BRUSH CREEK

085E42906, Jackson, IA

Built 1960 Load: 15.7 t ADT: 30

S 104TH AVE E

Poor

Over: LITTLE ELK CREEK

078182303, Jasper, IA

Built 1932 Load: 15.7 t ADT: 25

FM

Poor

Over: STREAM

076112402, Keokuk, IA

Built 1950 Load: 15.7 t ADT: 30

LOC 200TH ST

Poor

Over: FOUR MILE CREEK

095291701, Kossuth, IA

Built 1974 Load: 15.7 t ADT: 26

LOCAL

Poor

Over: DRAINAGE

075142605, Mahaska, IA

Built 1951 Load: 15.7 t ADT: 45

LOCAL

Poor

Over: DRAINAGE

075162206, Mahaska, IA

Built 1973 Load: 15.7 t ADT: 80

LOCAL

Poor

Over: DRAINAGE

077140804, Mahaska, IA

Built 1957 Load: 15.7 t ADT: 20

FM

Poor

Over: WILLOW CREEK

082421202, Monona, IA

Built 1952 Load: 15.7 t ADT: 40

FM

Poor

Over: PINE CREEK

077E11710, Muscatine, IA

Built 1955 Load: 15.7 t ADT: 60

190TH STREET

Poor

Over: WEST TARKIO CREEK

069382001, Page, IA

Built 1958 Load: 15.7 t ADT: 71

LOCAL

Poor

Over: LITTLE CEDAR CREEK

091341801, Pocahontas, IA

Built 1964 Load: 15.7 t ADT: 30

LOCAL

Poor

Over: DRAINAGE

074381206, Pottawattamie, IA

Built 1952 Load: 15.7 t ADT: 29

LOCAL

Poor

Over: SMALL STREAM

081131202, Poweshiek, IA

Built 1950 Load: 15.7 t ADT: 34

FM

Poor

Over: PLATTE RIVER

070310601, Ringgold, IA

Built 1955 Load: 15.7 t ADT: 79

LOCAL RD

Poor

Over: OTTER CREEK

086382901, Sac, IA

Built 1968 Load: 15.7 t ADT: 45

FM

Poor

Over: SMALL STREAM

067332102, Taylor, IA

Built 1951 Load: 15.7 t ADT: 40

FM

Poor

Over: GARRETSON DITCH

087460501, Woodbury, IA

Built 1955 Load: 15.7 t ADT: 71

S 120TH AVE E

Poor

Over: SMALL STREAM

078183401, Jasper, IA

Built 1980 Load: 15.8 t ADT: 11

FM

Poor

Over: OVER UP RR

076150703, Mahaska, IA

Built 1961 Load: 15.8 t ADT: 370

SYCAMORE AVE

Poor

Over: STREAM

070360504, Page, IA

Built 1961 Load: 15.8 t ADT: 45

260TH ST

Poor

Over: DRY BRANCH

091442801, Plymouth, IA

Built 1956 Load: 15.8 t ADT: 34

LOCAL

Poor

Over: STREAM

067301204, Ringgold, IA

Built 1993 Load: 15.8 t ADT: 15

LOCAL

Poor

Over: CHARITON RIVER

069220501, Wayne, IA

Built 1983 Load: 15.8 t ADT: 20

FM

Poor

Over: CREEK

092363402, Buena Vista, IA

Built 1964 Load: 15.9 t ADT: 339

LOCAL/ROCKPORT

Poor

Over: WATERWAY

075343203, Cass, IA

Built 1900 Load: 15.9 t ADT: 89

KING AVE

Poor

Over: ROCK CR

080032308, Cedar, IA

Built 1946 Load: 15.9 t ADT: 50

FM

Poor

Over: SMALL STREAM

070152511, Davis, IA

Built 1940 Load: 15.9 t ADT: 70

FM

Poor

Over: WELDON RIVER

069240903, Decatur, IA

Built 1957 Load: 15.9 t ADT: 15

FM

Poor

Over: BIG HOLLOW CREEK

071033002, Des Moines, IA

Built 1956 Load: 15.9 t ADT: 90

FM

Poor

Over: CREEK

090021404, Dubuque, IA

Built 1959 Load: 15.9 t ADT: 170

HAMLET RD.

Poor

Over: NUTTING CR

095080205, Fayette, IA

Built 1917 Load: 15.9 t ADT: 59

LOCAL

Poor

Over: BRANCH OLD MAN'S CREEK

079110102, Iowa, IA

Built 1925 Load: 15.9 t ADT: 71

LOCAL

Poor

Over: TETE DE MORTS CREEK

087E31606, Jackson, IA

Built 1984 Load: 15.9 t ADT: 20

W 80TH ST S

Poor

Over: SEVERS CREEK

079200410, Jasper, IA

Built 1951 Load: 15.9 t ADT: 123

Showing 17,351-17,400 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.