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

FM

Poor

Over: BACON CREEK

088420503, Woodbury, IA

Built 1968 Load: 26.3 t ADT: 390

FM

Poor

Over: IOWA RIVER

093231901, Wright, IA

Built 1965 Load: 26.3 t ADT: 977

KENTUCKY AVENUE

Poor

Over: WEST FORK 102 RIVER

071341302, Adams, IA

Built 1967 Load: 26.4 t ADT: 34

250TH STREET

Poor

Over: WEST FORK 102 RIVER

071342103, Adams, IA

Built 1969 Load: 26.4 t ADT: 110

240 TH STREET

Poor

Over: STREAM

071351603, Adams, IA

Built 1971 Load: 26.4 t ADT: 20

HIGHWAY F-62 W

Poor

Over: S SKUNK RIVER

078191003, Jasper, IA

Built 1961 Load: 26.4 t ADT: 810

LOCAL

Poor

Over: SMALL STREAM

081203203, Jasper, IA

Built 1921 Load: 26.4 t ADT: 26

ADAMS-TAYLOR ST

Poor

Over: STREAM

070330201, Taylor, IA

Built 1970 Load: 26.4 t ADT: 34

ADAMS-TAYLOR ST

Poor

Over: LONZO CREEK

070330603, Taylor, IA

Built 1967 Load: 26.4 t ADT: 5

LOCAL

Poor

Over: CREEK

073260303, Clarke, IA

Built 1980 Load: 26.5 t ADT: 60

95TH ST

Poor

Over: SMALL STREAM

091193003, Franklin, IA

Built 1952 Load: 26.5 t ADT: 51

180TH ST

Poor

Over: DRAINAGE DITCH #10

095262903, Hancock, IA

Built 1994 Load: 26.5 t ADT: 21

SIOUX AVE

Poor

Over: STREAM

079053102, Johnson, IA

Built 1966 Load: 26.5 t ADT: 234

FM

Poor

Over: DRAINAGE

074270803, Madison, IA

Built 1930 Load: 26.5 t ADT: 40

FM

Poor

Over: DD #123

094310502, Palo Alto, IA

Built 1966 Load: 26.5 t ADT: 20

LOCAL

Poor

Over: BEAVER CREEK

084282901, Boone, IA

Built 1915 Load: 26.6 t ADT: 11

FM

Poor

Over: MAPLE RIVER

090382002, Buena Vista, IA

Built 1964 Load: 26.6 t ADT: 450

T64

Poor

Over: SMALL STREAM

093150602, Butler, IA

Built 1968 Load: 26.6 t ADT: 776

LOCAL-520TH ST

Poor

Over: WILLOW CR

092413001, Cherokee, IA

Built 1973 Load: 26.6 t ADT: 26

FM 450TH ST

Poor

Over: GREY CREEK

093402201, Cherokee, IA

Built 1970 Load: 26.6 t ADT: 319

FM 310TH AVE

Poor

Over: DITCH NO.60

096352202, Clay, IA

Built 1967 Load: 26.6 t ADT: 259

FM 350TH ST

Poor

Over: SPRING CREEK

096381403, Clay, IA

Built 1963 Load: 26.6 t ADT: 1,806

KAHLE AVE

Poor

Over: CARLAN CR

091030304, Clayton, IA

Built 1900 Load: 26.6 t ADT: 21

FM

Poor

Over: SMALL STREAM

085412101, Crawford, IA

Built 1967 Load: 26.6 t ADT: 627

FM

Poor

Over: OVER-FLOW-NORTH RIVER

077263102, Madison, IA

Built 1970 Load: 26.6 t ADT: 880

LOCAL

Poor

Over: LITTLE MUCHAKINOCK

075153104, Mahaska, IA

Built 1965 Load: 26.6 t ADT: 290

FM

Poor

Over: DRAINAGE DITCH 2

076040701, Muscatine, IA

Built 1969 Load: 26.6 t ADT: 840

FM

Poor

Over: PILOT CREEK

092310502, Pocahontas, IA

Built 1970 Load: 26.6 t ADT: 439

FM

Poor

Over: CROOKED CK DD #60

092321101, Pocahontas, IA

Built 1966 Load: 26.6 t ADT: 11

FM

Poor

Over: SOUTH ENGLISH RIVER

078142802, Poweshiek, IA

Built 1964 Load: 26.6 t ADT: 480

LOCAL

Poor

Over: STREAM

081130905, Poweshiek, IA

Built 1981 Load: 26.6 t ADT: 11

FM

Poor

Over: PLATTE RIVER

069312201, Ringgold, IA

Built 1962 Load: 26.6 t ADT: 40

FM

Poor

Over: INDIAN CREEK

094472602, Sioux, IA

Built 1967 Load: 26.6 t ADT: 649

IRR FM

Poor

Over: BRANCH OF RICHLAND CREEK

082153303, Tama, IA

Built 1967 Load: 26.6 t ADT: 304

LOCAL

Poor

Over: TRIB DES MOINES RIVER

070110703, Van Buren, IA

Built 1950 Load: 26.6 t ADT: 60

LOCAL

Poor

Over: BR TO DES MOINES RIVER

072133107, Wapello, IA

Built 1968 Load: 26.6 t ADT: 590

FM

Poor

Over: CEDAR RIVER

081042803, Cedar, IA

Built 1971 Load: 26.7 t ADT: 950

S 68TH AVE E

Poor

Over: SMALL STREAM

079183303, Jasper, IA

Built 1997 Load: 26.7 t ADT: 50

LOCAL

Poor

Over: BRUSH CREEK

077202303, Marion, IA

Built 1910 Load: 26.7 t ADT: 41

LCL-MERRILL RD

Poor

Over: DRAINAGE

071410104, Mills, IA

Built 1964 Load: 26.7 t ADT: 50

FM

Poor

Over: PRATT CREEK

085122702, Benton, IA

Built 1971 Load: 26.8 t ADT: 15

OXLEY RD

Poor

Over: INDIAN CREEK

88-11-09-02-10, Black Hawk, IA

Built 1900 Load: 26.8 t ADT: 26

LOCAL

Poor

Over: CREEK

094142401, Chickasaw, IA

Built 1953 Load: 26.8 t ADT: 47

FM

Poor

Over: BRANCH BEAVER CREEK

089171502, Grundy, IA

Built 1966 Load: 26.8 t ADT: 393

175TH ST

Poor

Over: BR MEAD CREEK

098133103, Howard, IA

Built 1989 Load: 26.8 t ADT: 31

LOC HOWARD AVE

Poor

Over: CRANE CREEK

099132908, Howard, IA

Built 1942 Load: 26.8 t ADT: 82

HIGHWAY F-62 E

Poor

Over: ELK CREEK

078181003, Jasper, IA

Built 1962 Load: 26.8 t ADT: 1,370

FM

Poor

Over: ROCK CREEK

081172001, Jasper, IA

Built 1963 Load: 26.8 t ADT: 530

LOCAL

Poor

Over: DRAINAGE

077143204, Mahaska, IA

Built 1950 Load: 26.8 t ADT: 45

FM

Poor

Over: BUCK CREEK

077150805, Mahaska, IA

Built 1957 Load: 26.8 t ADT: 30

Showing 18,701-18,750 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.