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

FA-PADDOCK AVE

Poor

Over: HUNTERS BRANCH

071402301, Mills, IA

Built 1962 Load: 22.7 t ADT: 51

FM

Poor

Over: CREEK

076031813, Muscatine, IA

Built 1970 Load: 22.7 t ADT: 200

FIELD ENTRANCE

Poor

Over: DRAINAGE (SDB)

070363204, Page, IA

Built 1990 Load: 22.7 t ADT: 10

IRR LOCAL

Poor

Over: BRANCH OF RICHLAND CREEK

082152902, Tama, IA

Built 1988 Load: 22.7 t ADT: 11

LOCAL

Poor

Over: MIDDLE 102 RIVER

067340501, Taylor, IA

Built 1978 Load: 22.7 t ADT: 5

170TH ST

Poor

Over: STREAM

069211102, Wayne, IA

Built 2008 Load: 22.7 t ADT: 15

LOCAL

Poor

Over: JACKSON CREEK

069212403, Wayne, IA

Built 1967 Load: 22.7 t ADT: 34

LOCAL

Poor

Over: STREAM

087420502, Woodbury, IA

Built 1950 Load: 22.7 t ADT: 15

LOCAL

Poor

Over: STREAM

089443106, Woodbury, IA

Built 1950 Load: 22.7 t ADT: 80

NODAWAY RVR RD

Poor

Over: EAST NODAWAY RIVER

072343603, Adams, IA

Built 1930 Load: 22.8 t ADT: 20

FM

Poor

Over: CRANE CREEK

095111401, Chickasaw, IA

Built 1966 Load: 22.8 t ADT: 432

FM

Poor

Over: LITTLE WAPSIPINICON

095131603, Chickasaw, IA

Built 1967 Load: 22.8 t ADT: 786

LOCAL RD

Poor

Over: CEDAR CREEK

076282902, Madison, IA

Built 1952 Load: 22.8 t ADT: 29

LOCAL

Poor

Over: JIM CREEK

077291402, Madison, IA

Built 1981 Load: 22.8 t ADT: 20

FM

Poor

Over: CREEK

078360301, Audubon, IA

Built 1948 Load: 22.9 t ADT: 20

LOCAL - 770TH

Poor

Over: SMALL

075343602, Cass, IA

Built 1980 Load: 22.9 t ADT: 91

280TH ST

Poor

Over: MIDDLE BR WAPSINONOC CR

079040301, Cedar, IA

Built 1950 Load: 22.9 t ADT: 26

LOCAL

Poor

Over: CREEK

094133404, Chickasaw, IA

Built 1971 Load: 22.9 t ADT: 10

LOCAL

Poor

Over: SMALL STREAM

095121810, Chickasaw, IA

Built 1975 Load: 22.9 t ADT: 135

LOCAL

Poor

Over: LITTLE WAPSIPINICON

095130202, Chickasaw, IA

Built 1971 Load: 22.9 t ADT: 59

W25

Poor

Over: CREEK

093091404, Fayette, IA

Built 1968 Load: 22.9 t ADT: 206

X AVE

Poor

Over: UNAMED CREEK

093102002, Fayette, IA

Built 1928 Load: 22.9 t ADT: 70

NILES TRAIL

Poor

Over: HARRIS GROVE CREEK

079433603, Harrison, IA

Built 1975 Load: 22.9 t ADT: 29

W 56TH ST S

Poor

Over: BUCK CREEK

078201302, Jasper, IA

Built 1927 Load: 22.9 t ADT: 21

S 28TH AVE W

Poor

Over: SMALL STREAM

079210901, Jasper, IA

Built 1917 Load: 22.9 t ADT: 71

FM

Poor

Over: MINERVA CREEK

084200105, Marshall, IA

Built 1915 Load: 22.9 t ADT: 15

FM

Poor

Over: STREAM

089420702, Woodbury, IA

Built 1981 Load: 22.9 t ADT: 270

EAST ST

Poor

Over: WILLOW CREEK

S. of IA 141, Carroll, IA

Built 1964 Load: 23.0 t ADT: 580

155TH ST

Poor

Over: YANKEE RUN

082013405, Cedar, IA

Built 1995 Load: 23.0 t ADT: 90

LOCAL

Poor

Over: CREEK

089023403, Dubuque, IA

Built 1998 Load: 23.0 t ADT: 206

LOCAL ROAD

Poor

Over: N FORK OF BEAVER CREEK

089171902, Grundy, IA

Built 1947 Load: 23.0 t ADT: 15

FM

Poor

Over: ODEBOLT CREEK

087392424, Ida, IA

Built 1964 Load: 23.0 t ADT: 589

S 24TH AVE E

Poor

Over: SMALL STREAM

079190513, Jasper, IA

Built 1986 Load: 23.0 t ADT: 104

LOCAL ROAD

Poor

Over: ALLEN CREEK

098433002, Lyon, IA

Built 1900 Load: 23.0 t ADT: 26

LOCAL

Poor

Over: DRAINAGE

072172503, Monroe, IA

Built 1941 Load: 23.0 t ADT: 20

280TH STREET

Poor

Over: WEST MILL CREEK

067370701, Page, IA

Built 1940 Load: 23.0 t ADT: 34

LOCAL

Poor

Over: BR MIDDLE FK GRAND RIVER

068303201, Ringgold, IA

Built 1940 Load: 23.0 t ADT: 29

LOCAL - MEMPHIS

Poor

Over: SMALL STREAM

075370105, Cass, IA

Built 1978 Load: 23.1 t ADT: 5

RANCH AVE

Poor

Over: SMALL STREAM

078191104, Jasper, IA

Built 1974 Load: 23.1 t ADT: 70

FM

Poor

Over: RACOON RIVER

086351101, Sac, IA

Built 1920 Load: 23.1 t ADT: 120

WELLS FERRY RD

Poor

Over: SPENCER CREEK

078E50804, Scott, IA

Built 1972 Load: 23.1 t ADT: 1,700

LOCAL

Poor

Over: BRANCH IOWA RIVER

084160301, Tama, IA

Built 1985 Load: 23.1 t ADT: 26

LOCAL

Poor

Over: CREEK

075322703, Adair, IA

Built 1954 Load: 23.2 t ADT: 62

LOCAL

Poor

Over: SMALL STREAM

069142303, Davis, IA

Built 1990 Load: 23.2 t ADT: 369

M AVE.

Poor

Over: VOLGA RIVER

092083102, Fayette, IA

Built 1939 Load: 23.2 t ADT: 29

FIELD ENTRANCE

Poor

Over: DRAINAGE (SDB)

070392705, Page, IA

Built 1900 Load: 23.2 t ADT: 10

330TH ST

Poor

Over: CREEK

090433103, Plymouth, IA

Built 1956 Load: 23.2 t ADT: 60

LOCAL

Poor

Over: CAMP CREEK

078222408, Polk, IA

Built 1930 Load: 23.2 t ADT: 79

LOCAL ROAD

Poor

Over: CREEK

078222801, Polk, IA

Built 1962 Load: 23.2 t ADT: 159

LOCAL RD

Poor

Over: BR YELLOW RIVER

096040904, Allamakee, IA

Built 1941 Load: 23.3 t ADT: 11

Showing 18,351-18,400 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.