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

235TH ST

Fair

Over: ALLEN CREEK

079441003, Harrison, IA

Built 2015 Load: 42.1 t ADT: 25

FM

Fair

Over: SKUNK RIVER

070062508, Henry, IA

Built 1986 Load: 42.1 t ADT: 160

LOCAL

Fair

Over: BIG CEDAR CREEK

071072101, Henry, IA

Built 1988 Load: 42.1 t ADT: 51

FM

Fair

Over: SKUNK RIVER

072073206, Henry, IA

Built 1981 Load: 42.1 t ADT: 170

489TH AVE

Fair

Over: CREEK

085E52504, Jackson, IA

Built 2012 Load: 42.1 t ADT: 70

LOCAL

Fair

Over: CREEK

086E21604, Jackson, IA

Built 2002 Load: 42.1 t ADT: 78

LOCAL

Fair

Over: SEWER CREEK

096390102, O'Brien, IA

Built 1983 Load: 42.1 t ADT: 30

LOCAL

Fair

Over: SPRING CREEK

078220705, Polk, IA

Built 1975 Load: 42.1 t ADT: 597

LOCAL

Fair

Over: SMALL

096471804, Sioux, IA

Built 1978 Load: 42.1 t ADT: 30

FM

Fair

Over: CLANTON CREEK

076253206, Warren, IA

Built 1985 Load: 42.1 t ADT: 100

FM

Fair

Over: NORTH R OVERFLOW CHANNEL

077242104, Warren, IA

Built 1986 Load: 42.1 t ADT: 2,998

HESS ROAD

Fair

Over: DRAINAGE

CITY CULVERT NO. 54C, Black Hawk, IA

Built 1992 Load: 42.2 t ADT: 4,635

NB I-35

Fair

Over: CERRO GORDO COUNTY TRAIL

0.7 mi. N of jct. SR B65, Cerro Gordo, IA

Built 1972 Load: 42.2 t ADT: 8,850

200TH AVE

Fair

Over: SMALL

080E20204, Clinton, IA

Built 1979 Load: 42.2 t ADT: 104

FM 50TH ST

Fair

Over: BEAVER CREEK

100133201, Howard, IA

Built 1980 Load: 42.3 t ADT: 226

NE RAMP

Fair

Over: LITTLE BEAR CREEK

175 ft. E of Jct. SR V38, Iowa, IA

Built 1963 Load: 42.3 t ADT: 390

FM

Fair

Over: MINERVA CREEK

084200202, Marshall, IA

Built 1995 Load: 42.3 t ADT: 363

FM

Fair

Over: MIDDLE MINERVA CREEK

084200403, Marshall, IA

Built 2005 Load: 42.3 t ADT: 147

FM

Fair

Over: BIG MINERVA CREEK

085202606, Marshall, IA

Built 1999 Load: 42.3 t ADT: 187

HACKBERRY AVE

Fair

Over: TARKIO RIVER

067380806, Page, IA

Built 1975 Load: 42.3 t ADT: 199

270TH STREET

Fair

Over: WEST TARKIO CREEK

067390401, Page, IA

Built 1979 Load: 42.3 t ADT: 300

LOCAL

Fair

Over: OVER BNSF RR

072310902, Union, IA

Built 1997 Load: 42.3 t ADT: 91

I 35

Fair

Over: DRAINAGE DITCH

0.5 mi. S of Jct. SR B65, Cerro Gordo, IA

Built 1972 Load: 42.4 t ADT: 17,300

215 AVE

Fair

Over: DEEP CREEK

083E23604, Clinton, IA

Built 2000 Load: 42.4 t ADT: 26

FM

Fair

Over: SMALL STREAM

089410102, Ida, IA

Built 1974 Load: 42.4 t ADT: 290

FM

Fair

Over: SMALL STREAM

089411304, Ida, IA

Built 1974 Load: 42.4 t ADT: 290

FM

Fair

Over: S FORK MAQUOKETA RIVER

084E10304, Jackson, IA

Built 1987 Load: 42.4 t ADT: 230

FM

Fair

Over: MIDDLE RIVER

075270405, Madison, IA

Built 1987 Load: 42.4 t ADT: 139

US 218 & IA 9

Fair

Over: SPRING CREEK

1.9 MI. N OF S JCT. IA 9, Mitchell, IA

Built 1967 Load: 42.4 t ADT: 2,460

SW 42ND ST

Fair

Over: FRINK CREEK

078243000, Polk, IA

Built 1976 Load: 42.4 t ADT: 121

FM

Fair

Over: CRANE CREEK

097122101, Chickasaw, IA

Built 1998 Load: 42.5 t ADT: 246

ELKHORN ST

Fair

Over: STREAM

077182805, Marion, IA

Built 2005 Load: 42.5 t ADT: 135

FM

Fair

Over: JORDAN CREEK

082430905, Monona, IA

Built 2000 Load: 42.5 t ADT: 199

FM

Fair

Over: E FORK GRAND RIVER

070292401, Ringgold, IA

Built 2003 Load: 42.5 t ADT: 338

EB US 20

Fair

Over: N FORK MAQUOKETA RIVER

0.6 MI. W OF JCT IA 136, Dubuque, IA

Built 1986 Load: 42.6 t ADT: 5,400

WB I-80

Fair

Over: OVER IAIS RR

0.4 MILES WEST OF JCT 14, Jasper, IA

Built 1962 Load: 42.6 t ADT: 16,700

LOCAL

Fair

Over: SOUTH WALNUT CREEK

073093302, Jefferson, IA

Built 1986 Load: 42.6 t ADT: 15

IA 27 NB

Fair

Over: SUGAR CREEK

4.7 miles south of IA 2, Lee, IA

Built 1989 Load: 42.6 t ADT: 3,600

FM

Fair

Over: STREAM

073170802, Monroe, IA

Built 1978 Load: 42.6 t ADT: 30

FM

Fair

Over: BUTTRICK CREEK

086293201, Webster, IA

Built 1978 Load: 42.6 t ADT: 60

LOCAL

Fair

Over: SOLDIER CREEK

090282502, Webster, IA

Built 1979 Load: 42.6 t ADT: 30

LOCAL

Fair

Over: CREEK

096072404, Winneshiek, IA

Built 1965 Load: 42.6 t ADT: 78

LOCAL

Fair

Over: STREAM

074321302, Adair, IA

Built 1970 Load: 42.8 t ADT: 26

LOCAL

Fair

Over: CREEK

096182702, Floyd, IA

Built 1991 Load: 42.8 t ADT: 33

D AVE / N65

Fair

Over: CEDAR CREEK

085322202, Greene, IA

Built 1955 Load: 42.8 t ADT: 338

US 151

Fair

Over: BRANCH CLEAR CREEK

2.6 MI. S OF S JCT. US 6, Iowa, IA

Built 1984 Load: 42.8 t ADT: 1,510

168TH AVE

Fair

Over: CREEK

084E20206, Jackson, IA

Built 2018 Load: 42.8 t ADT: 26

LOCAL

Fair

Over: SMALL

000000000, Jackson, IA

Built 2009 Load: 42.8 t ADT: 39

IA 191

Fair

Over: DRAINAGE DITCH

2.7 MI. N OF JCT. IA 44, Shelby, IA

Built 1986 Load: 42.8 t ADT: 790

FM

Fair

Over: N TIMBER CR

083170808, Marshall, IA

Built 1989 Load: 42.9 t ADT: 157

Showing 8,301-8,350 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.