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

LOC 215TH ST

Poor

Over: PIGEON CREEK

080413603, Harrison, IA

Built 1955 Load: 14.8 t ADT: 26

LOCAL

Poor

Over: PRAIRIE CREEK

080202701, Jasper, IA

Built 1923 Load: 14.8 t ADT: 47

FM

Poor

Over: MIDDLE RIVER

075281804, Madison, IA

Built 1935 Load: 14.8 t ADT: 11

FM

Poor

Over: BRANCH, SKUNK RIVER

081231303, Polk, IA

Built 1968 Load: 14.8 t ADT: 131

LOCAL

Poor

Over: SMALL STREAM

071152002, Wapello, IA

Built 1983 Load: 14.8 t ADT: 26

LOCAL

Poor

Over: CREEK

075323101, Adair, IA

Built 1951 Load: 14.9 t ADT: 46

LOCAL

Poor

Over: CREEK

080361403, Audubon, IA

Built 1967 Load: 14.9 t ADT: 26

LOCAL

Poor

Over: BR LITTLE SIOUX RIVER

092382501, Buena Vista, IA

Built 1922 Load: 14.9 t ADT: 20

CEDAR\JONES RD

Poor

Over: BR PIONEER CR

082030401, Cedar, IA

Built 1992 Load: 14.9 t ADT: 11

FM

Poor

Over: LITTLE RIVER

067251003, Decatur, IA

Built 1957 Load: 14.9 t ADT: 110

LOCAL

Poor

Over: SOUTH RACCOON RIVER

080322905, Guthrie, IA

Built 1940 Load: 14.9 t ADT: 11

EAGLE AVE

Poor

Over: BRADLEY CR

079082704, Johnson, IA

Built 1915 Load: 14.9 t ADT: 31

JOHNSON-IOWA RD

Poor

Over: BR OLD MANS CR

079083102, Johnson, IA

Built 1915 Load: 14.9 t ADT: 5

FM

Poor

Over: GRAND RIVER

074291703, Madison, IA

Built 1940 Load: 14.9 t ADT: 379

LOCAL

Poor

Over: DRAINAGE

076153103, Mahaska, IA

Built 1963 Load: 14.9 t ADT: 100

LOCAL

Poor

Over: DRAINAGE

076172706, Mahaska, IA

Built 1957 Load: 14.9 t ADT: 100

LCL-380TH ST

Poor

Over: INDIAN CREEK

072402108, Mills, IA

Built 1964 Load: 14.9 t ADT: 50

FM

Poor

Over: NO NAME CREEK

086370302, Sac, IA

Built 1954 Load: 14.9 t ADT: 45

180TH ST

Poor

Over: WEST BR INDIAN CREEK

084231401, Story, IA

Built 1900 Load: 14.9 t ADT: 15

LOCAL

Poor

Over: PLATTE BRANCH

069323602, Taylor, IA

Built 1970 Load: 14.9 t ADT: 15

LOCAL

Poor

Over: DRAINAGE DITCH

099263402, Winnebago, IA

Built 1964 Load: 14.9 t ADT: 20

LOCAL

Poor

Over: STREAM

087453401, Woodbury, IA

Built 1979 Load: 14.9 t ADT: 15

FM

Poor

Over: COOPER CREEK

068191002, Appanoose, IA

Built 1923 Load: 15.0 t ADT: 25

LOCAL - 640TH

Poor

Over: CREEK

077363508, Cass, IA

Built 1977 Load: 15.0 t ADT: 15

Q AVE

Poor

Over: VOLGA RIVER

093092802, Fayette, IA

Built 1940 Load: 15.0 t ADT: 33

LOCAL

Poor

Over: BLACK HAWK CREEK

088171101, Grundy, IA

Built 1977 Load: 15.0 t ADT: 70

LOCAL

Poor

Over: CREEK

086203604, Hardin, IA

Built 1986 Load: 15.0 t ADT: 26

LOCAL

Poor

Over: CREEK

088203002, Hardin, IA

Built 1991 Load: 15.0 t ADT: 21

VIENNA AVE

Poor

Over: PIGEON CREEK

079410102, Harrison, IA

Built 1967 Load: 15.0 t ADT: 60

FM VICTORY AVE

Poor

Over: UPPER IOWA

100112204, Howard, IA

Built 1949 Load: 15.0 t ADT: 393

FM

Poor

Over: PRAIRIE CREEK

080201104, Jasper, IA

Built 1965 Load: 15.0 t ADT: 50

180TH STREET

Poor

Over: STREAM

069391401, Page, IA

Built 1953 Load: 15.0 t ADT: 11

270TH ST

Poor

Over: DEER CREEK

091433201, Plymouth, IA

Built 1900 Load: 15.0 t ADT: 15

260TH ST

Poor

Over: JOHN'S CREEK

091442501, Plymouth, IA

Built 1900 Load: 15.0 t ADT: 11

LOCAL

Poor

Over: STREAM

073280713, Union, IA

Built 1900 Load: 15.0 t ADT: 15

LOCAL

Poor

Over: YELLOW RIVER

096060307, Allamakee, IA

Built 1900 Load: 15.1 t ADT: 26

LOCAL

Poor

Over: CREEK

078342701, Audubon, IA

Built 1951 Load: 15.1 t ADT: 11

LOCAL

Poor

Over: DD 1-54

088342101, Calhoun, IA

Built 1900 Load: 15.1 t ADT: 26

LOCAL

Poor

Over: BUCK RUN

085333002, Carroll, IA

Built 1990 Load: 15.1 t ADT: 11

LOCAL - 680TH

Poor

Over: WATERWAY

076352104, Cass, IA

Built 1976 Load: 15.1 t ADT: 11

FM

Poor

Over: ROCK CREEK

079030206, Cedar, IA

Built 1945 Load: 15.1 t ADT: 170

LOCAL

Poor

Over: SMALL

096111302, Chickasaw, IA

Built 1976 Load: 15.1 t ADT: 30

LOCAL

Poor

Over: DRAINAGE

068262701, Decatur, IA

Built 1976 Load: 15.1 t ADT: 11

LOCAL

Poor

Over: SHANE CREEK

068272804, Decatur, IA

Built 1967 Load: 15.1 t ADT: 5

FM

Poor

Over: GRAND RIVER

069270106, Decatur, IA

Built 1962 Load: 15.1 t ADT: 45

2870 BIRCH AVE

Poor

Over: PLUM CREEK

097263202, Hancock, IA

Built 1975 Load: 15.1 t ADT: 51

FM

Poor

Over: BEAR CREEK

087193501, Hardin, IA

Built 1996 Load: 15.1 t ADT: 44

FM

Poor

Over: CREEK

089390801, Ida, IA

Built 1952 Load: 15.1 t ADT: 60

LOCAL

Poor

Over: SILVER CREEK

081211805, Jasper, IA

Built 1929 Load: 15.1 t ADT: 20

FM

Poor

Over: DEVIL CREEK

068052605, Lee, IA

Built 1948 Load: 15.1 t ADT: 250

Showing 17,251-17,300 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.