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

Fair

Over: CREEK

094153501, Floyd, IA

Built 1987 Load: 31.7 t ADT: 26

OLD HWY RD

Fair

Over: BLOODY RUN CREEK

095152006, Floyd, IA

Built 1959 Load: 31.7 t ADT: 687

HILLCREST AVE

Fair

Over: STREAM

083310504, Greene, IA

Built 1994 Load: 31.7 t ADT: 26

100 TH

Fair

Over: STREAM

085310201, Greene, IA

Built 1920 Load: 31.7 t ADT: 15

FM 780 120TH ST

Fair

Over: E. BR BOONE RIVER

094253001, Hancock, IA

Built 1980 Load: 31.7 t ADT: 518

FM 640 225TH ST

Fair

Over: BOONE RIVER

096263603, Hancock, IA

Built 1986 Load: 31.7 t ADT: 467

LOCAL

Fair

Over: HONEY CREEK

086210400, Hardin, IA

Built 1987 Load: 31.7 t ADT: 340

LOCAL

Fair

Over: HONEY CREEK

087213002, Hardin, IA

Built 1981 Load: 31.7 t ADT: 34

US 30

Fair

Over: BOYER RIVER

3.7 mi. W of jct. IA 37, Harrison, IA

Built 1968 Load: 31.7 t ADT: 3,090

IA 175

Fair

Over: BRANCH ODEBOLT CREEK

0.5 mi. W of SR M31, Ida, IA

Built 1985 Load: 31.7 t ADT: 2,040

IA 149

Fair

Over: SOUTH SKUNK RIVER

4.0 MI. N OF IA 78, Keokuk, IA

Built 1986 Load: 31.7 t ADT: 1,190

IA 27

Fair

Over: SUGAR CREEK

6.3 mi. N of MO St. Line, Lee, IA

Built 2001 Load: 31.7 t ADT: 7,200

IA 9

Fair

Over: MUD CREEK

0.2 mi. W of Jct. SR K30, Lyon, IA

Built 1975 Load: 31.7 t ADT: 3,270

FM

Fair

Over: SMALL STREAM

100431901, Lyon, IA

Built 1978 Load: 31.7 t ADT: 60

FM

Fair

Over: TOM CREEK

100432201, Lyon, IA

Built 1977 Load: 31.7 t ADT: 60

ORCHARD RD

Fair

Over: SPRING CREEK

097160708, Mitchell, IA

Built 1980 Load: 31.7 t ADT: 520

JERSEY AVE

Fair

Over: ROCK OAK CREEK

097171506, Mitchell, IA

Built 1974 Load: 31.7 t ADT: 34

RAMPART AVE

Fair

Over: CREEK

100162402, Mitchell, IA

Built 1967 Load: 31.7 t ADT: 167

US 34

Fair

Over: INDIAN CREEK

1.2 MI. E OF US 59, Montgomery, IA

Built 1964 Load: 31.7 t ADT: 4,030

LOCAL

Fair

Over: SIN CREEK

073362502, Montgomery, IA

Built 1964 Load: 31.7 t ADT: 15

FM K-18

Fair

Over: STREAM

091481104, Plymouth, IA

Built 1979 Load: 31.7 t ADT: 429

LOCAL RD

Fair

Over: DRAINAGE DITCH

093321707, Pocahontas, IA

Built 1955 Load: 31.7 t ADT: 379

FAIRMOUNT ST.

Fair

Over: DUCK CREEK

000000000, Scott, IA

Built 1983 Load: 31.7 t ADT: 10,500

FM

Fair

Over: COATES CREEK

069082001, Van Buren, IA

Built 1975 Load: 31.7 t ADT: 50

FM

Fair

Over: CEDAR CREEK

072120308, Wapello, IA

Built 1965 Load: 31.7 t ADT: 150

LOCAL LEGNO

Fair

Over: CREEK

099082404, Winneshiek, IA

Built 1961 Load: 31.7 t ADT: 11

FM

Fair

Over: CREEK

080342402, Audubon, IA

Built 1937 Load: 31.8 t ADT: 15

LOCAL

Fair

Over: BLUE CREEK

086092408, Benton, IA

Built 1987 Load: 31.8 t ADT: 50

C13

Fair

Over: SMALL

093161201, Butler, IA

Built 1983 Load: 31.8 t ADT: 727

LOCAL

Fair

Over: E. CEDAR CR

087311603, Calhoun, IA

Built 1981 Load: 31.8 t ADT: 5

LOCAL

Fair

Over: BRANCH 976 ON DD 181

089342002, Calhoun, IA

Built 1982 Load: 31.8 t ADT: 20

LOCAL

Fair

Over: FIELD STREAM

084351402, Carroll, IA

Built 1985 Load: 31.8 t ADT: 379

FM - BOSTON

Fair

Over: TROUBLESOME RIVER

077351003, Cass, IA

Built 1977 Load: 31.8 t ADT: 45

550TH ST

Fair

Over: FIDDLE CREEK

091420801, Cherokee, IA

Built 1954 Load: 31.8 t ADT: 15

LOC 302 ST

Fair

Over: SMALL STREAM

087031403, Delaware, IA

Built 1984 Load: 31.8 t ADT: 49

335TH ST

Fair

Over: SMALL STREAM

087043203, Delaware, IA

Built 1988 Load: 31.8 t ADT: 15

LOCAL DOVE RD

Fair

Over: STREAM

089060202, Delaware, IA

Built 1990 Load: 31.8 t ADT: 39

FM

Fair

Over: PETERS CREEK

094161603, Floyd, IA

Built 1986 Load: 31.8 t ADT: 412

US 218

Fair

Over: STREAM

0.6 mi. N of Jct. SR B-60, Floyd, IA

Built 2001 Load: 31.8 t ADT: 10,200

2240 CRANE AVE

Fair

Over: DD 10

096263302, Hancock, IA

Built 1976 Load: 31.8 t ADT: 51

FM

Fair

Over: N FORK MAQUOKETA RIVER

085E11406, Jackson, IA

Built 2005 Load: 31.8 t ADT: 290

FM

Fair

Over: CREEK

085E22704, Jackson, IA

Built 1987 Load: 31.8 t ADT: 230

80TH AVE.

Fair

Over: MINERAL CREEK

085022504, Jones, IA

Built 1979 Load: 31.8 t ADT: 15

MIDDLE RD

Fair

Over: PRICES CREEK

000000000, Lee, IA

Built 1977 Load: 31.8 t ADT: 820

OLD RIVER RD

Fair

Over: PLEASANT RUN CR.

082060805, Linn, IA

Built 1985 Load: 31.8 t ADT: 207

IVANHOE RD

Fair

Over: PLEASANT RUN CK

082061803, Linn, IA

Built 1985 Load: 31.8 t ADT: 511

LOCAL

Fair

Over: SMALL STREAM

075033204, Louisa, IA

Built 1982 Load: 31.8 t ADT: 41

US 6 & IA 38

Fair

Over: IAIS RR

1.2 MI. E OF JCT. IA 38, Muscatine, IA

Built 1930 Load: 31.8 t ADT: 5,100

LOCAL

Fair

Over: BEAVER CREEK DD #98

094323202, Palo Alto, IA

Built 1984 Load: 31.8 t ADT: 26

FM

Fair

Over: DD #175

095330802, Palo Alto, IA

Built 1984 Load: 31.8 t ADT: 30

Showing 6,101-6,150 of 20,753 bridges

Related

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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.