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

EGRET RD

Fair

Over: STREAM

093052804, Clayton, IA

Built 1940 Load: 10.0 t ADT: 79

REC. TRAFFIC

Fair

Over: PLEASANT CREEK

8.0 KM S. OF BELLEVUE, IA, Jackson, IA

Built 1972 Load: 10.0 t

FM

Fair

Over: HICKORY CREEK

074193304, Marion, IA

Built 1953 Load: 10.0 t ADT: 90

FM

Fair

Over: WEST NODAWAY TRIB

072361101, Montgomery, IA

Built 1959 Load: 10.0 t ADT: 50

LOCAL

Fair

Over: WALNUT CREEK

073382001, Montgomery, IA

Built 1957 Load: 10.0 t ADT: 60

213TH ST

Fair

Over: EAST BR INDIAN CREEK

084223603, Story, IA

Built 1925 Load: 10.0 t ADT: 26

FM

Fair

Over: TWELVE MILE CREEK

071290204, Union, IA

Built 1957 Load: 10.0 t ADT: 40

LOCAL RD

Fair

Over: NORTH RIVER

077272904, Madison, IA

Built 1920 Load: 10.1 t ADT: 40

255 AVENUE

Fair

Over: COOPER CREEK

068420704, Fremont, IA

Built 1945 Load: 10.2 t ADT: 31

200TH AVE.

Fair

Over: WHITE OAK CREEK

083042502, Jones, IA

Built 1947 Load: 10.2 t ADT: 49

LOCAL ROAD

Fair

Over: PINE CREEK

100090802, Winneshiek, IA

Built 1967 Load: 10.2 t ADT: 49

LOCAL RD

Fair

Over: MIDDLE RIVER

075290606, Madison, IA

Built 1930 Load: 10.3 t ADT: 29

LOCAL

Fair

Over: UNNAMED CREEK

071133101, Wapello, IA

Built 1995 Load: 10.3 t ADT: 50

LOCAL ROAD

Fair

Over: CREEK

100093102, Winneshiek, IA

Built 1900 Load: 10.3 t ADT: 29

FM

Fair

Over: PINE CREEK

089082907, Buchanan, IA

Built 1960 Load: 10.4 t ADT: 34

ECHO AVE

Fair

Over: STREAM

091050306, Clayton, IA

Built 1920 Load: 10.4 t ADT: 11

DOVE AVE

Fair

Over: ROBERTS CREEK

094050806, Clayton, IA

Built 1964 Load: 10.4 t ADT: 11

LOC FIREFLY RD

Fair

Over: STREAM

089051806, Delaware, IA

Built 1935 Load: 10.4 t ADT: 69

OASIS RD

Fair

Over: SMALL

079052402, Johnson, IA

Built 1979 Load: 10.4 t ADT: 61

FM CEDAR CK RD

Fair

Over: SMALL STREAM

081050101, Johnson, IA

Built 1946 Load: 10.4 t ADT: 160

LOCAL

Fair

Over: EAST BOYER RIVER

084371503, Crawford, IA

Built 1900 Load: 10.5 t ADT: 5

FM

Fair

Over: TRIBUTARY DES MOINES RIV

085272704, Boone, IA

Built 1930 Load: 10.6 t ADT: 71

FM

Fair

Over: NORTH RACOON RIVER

085332106https://siims.io, Carroll, IA

Built 1925 Load: 10.6 t ADT: 40

FM

Fair

Over: YELLOW RIVER

096070904, Winneshiek, IA

Built 1955 Load: 10.6 t ADT: 520

260TH ST

Fair

Over: SCHNEIDERS CREEK

093052803, Clayton, IA

Built 1915 Load: 10.7 t ADT: 41

LOCAL

Fair

Over: MAQUOKETA RIVER

085E33103, Jackson, IA

Built 1958 Load: 10.7 t ADT: 40

LOCAL

Fair

Over: GRAND RIVER

075301602, Adair, IA

Built 1999 Load: 10.8 t ADT: 11

130TH AVE.

Fair

Over: BRANCH KITTY CREEK

085021804, Jones, IA

Built 1969 Load: 10.8 t ADT: 62

FM RD F16

Fair

Over: BEE TREE CREEK

081400905, Shelby, IA

Built 1960 Load: 10.8 t ADT: 60

S62 CO RD 105

Fair

Over: DRAINAGE DITCH

100193403, Worth, IA

Built 1956 Load: 10.8 t ADT: 619

LOCAL

Fair

Over: NODAWAY RIVER,WEST FORK

074330901, Adair, IA

Built 1949 Load: 10.9 t ADT: 30

LOCAL

Fair

Over: MOSQUITO CREEK

079400911, Shelby, IA

Built 1960 Load: 10.9 t ADT: 51

640TH AVE

Fair

Over: WEST BR INDIAN CREEK

082220904, Story, IA

Built 1919 Load: 10.9 t ADT: 45

FM

Fair

Over: TROUT CREEK BRANCH

097080304, Winneshiek, IA

Built 1900 Load: 10.9 t ADT: 59

LOCAL

Fair

Over: FLOYD RIVER

097421002, O'Brien, IA

Built 1900 Load: 11.0 t ADT: 26

LOCAL

Fair

Over: MIDDLE 102 RIVER

070332002, Taylor, IA

Built 1959 Load: 11.0 t ADT: 34

LOCAL

Fair

Over: CREEK

070352102, Taylor, IA

Built 1961 Load: 11.0 t ADT: 20

LOCAL

Fair

Over: S ELK CREEK

068271601, Decatur, IA

Built 2011 Load: 11.1 t ADT: 11

LOCAL

Fair

Over: MILL CREEK

094411602, O'Brien, IA

Built 1924 Load: 11.1 t ADT: 50

LOCAL

Fair

Over: WHEELER CREEK

086373002, Sac, IA

Built 1932 Load: 11.1 t ADT: 15

LOCAL

Fair

Over: TRIB DES MOINES RIVER

069091501, Van Buren, IA

Built 1977 Load: 11.1 t ADT: 26

APPLE

Fair

Over: GALLS CREEK

095221902, Cerro Gordo, IA

Built 1954 Load: 11.2 t ADT: 21

LOCAL

Fair

Over: WILLOW CREEK

083411002, Crawford, IA

Built 2001 Load: 11.2 t ADT: 30

LOCAL ROAD

Fair

Over: PINE CREEK

100090701, Winneshiek, IA

Built 1965 Load: 11.2 t ADT: 49

GRANDVIEW RD

Fair

Over: VOLGA RIVER

092042605, Clayton, IA

Built 1960 Load: 11.3 t ADT: 491

CABLE AVE

Fair

Over: TURKEY RIVER

094062608, Clayton, IA

Built 1953 Load: 11.3 t ADT: 69

LOCAL

Fair

Over: STREAM

075133106, Keokuk, IA

Built 1950 Load: 11.3 t ADT: 11

LOCAL

Fair

Over: N ENGLISH RIVER

079131804, Poweshiek, IA

Built 1960 Load: 11.3 t ADT: 26

FM

Fair

Over: BR. TURKEY RIVER

097100801, Winneshiek, IA

Built 1953 Load: 11.3 t ADT: 69

FIELD ENTRANCE

Fair

Over: SIDE DITCH

093253001, Wright, IA

Built 1985 Load: 11.3 t ADT: 10

Showing 1,151-1,200 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.