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

LINN-BENTON RD.

Fair

Over: MORGAN CREEK

082080602, Linn, IA

Built 1993 Load: 57.3 t ADT: 147

AUSTIN RD

Fair

Over: BIG CR

084050601, Linn, IA

Built 1977 Load: 57.3 t ADT: 49

LOCAL ROAD

Fair

Over: CREEK

097080903, Winneshiek, IA

Built 1995 Load: 57.3 t ADT: 70

220TH STREET

Fair

Over: CREEK

081E40101, Clinton, IA

Built 1960 Load: 57.4 t ADT: 1,010

J 46

Fair

Over: STREAM

068230905, Wayne, IA

Built 1962 Load: 57.5 t ADT: 50

FM

Fair

Over: CREEK

085E32105, Jackson, IA

Built 1985 Load: 57.7 t ADT: 630

FM

Fair

Over: PAINT CREEK

T97NR5WSEC12SE, Allamakee, IA

Built 1990 Load: 57.8 t ADT: 147

NAPOLEON ST

Fair

Over: SNYDER CREEK

078060101, Johnson, IA

Built 1987 Load: 57.8 t ADT: 381

HENIK RD

Fair

Over: TRIB TO CEDAR RIVER

082051705, Linn, IA

Built 1998 Load: 57.9 t ADT: 78

MC CLELLAND RD

Fair

Over: SPRING CR

082052304, Linn, IA

Built 2002 Load: 57.9 t ADT: 29

MARION AIRPT RD

Fair

Over: CRABAPPLE CREEK

083060107, Linn, IA

Built 1992 Load: 57.9 t ADT: 70

O CONNER RD

Fair

Over: ALLEN CREEK

083062604, Linn, IA

Built 1990 Load: 57.9 t ADT: 59

SISLEY GROVE RD

Fair

Over: MORGAN CREEK

083083204, Linn, IA

Built 1994 Load: 57.9 t ADT: 33

WHITE RD

Fair

Over: DRY CR

084070203, Linn, IA

Built 1989 Load: 57.9 t ADT: 20

HORSESHOE LK RD

Fair

Over: TRIB TO CEDAR RIVER

084081404, Linn, IA

Built 1975 Load: 57.9 t ADT: 20

LINN-BENTON RD

Fair

Over: LITTLE GANNON CK

084083004, Linn, IA

Built 1992 Load: 57.9 t ADT: 88

MAXWELL RD

Fair

Over: TRIB WAPSIPINICON R

085050803, Linn, IA

Built 1998 Load: 57.9 t ADT: 78

GAME CLUB RD

Fair

Over: HEATONS CREEK

085061201, Linn, IA

Built 1999 Load: 57.9 t ADT: 78

SUTTON RD

Fair

Over: INDIAN CREEK

085061904, Linn, IA

Built 2002 Load: 57.9 t ADT: 78

LILLIE RD.

Fair

Over: INDIAN CREEK

085063204, Linn, IA

Built 1996 Load: 57.9 t ADT: 20

IOWA RD

Fair

Over: W OTTER CR,TRIB. TO

085070703, Linn, IA

Built 1977 Load: 57.9 t ADT: 20

IOWA RD

Fair

Over: W OTTER CREEK

085070703, Linn, IA

Built 1996 Load: 57.9 t ADT: 20

FISHEL RD

Fair

Over: E OTTER CREEK

085073307, Linn, IA

Built 2004 Load: 57.9 t ADT: 33

INDIAN BOUND.RD

Fair

Over: TRIB CEDAR R

085081704, Linn, IA

Built 1997 Load: 57.9 t ADT: 137

RED BRIDGE RD

Fair

Over: BOULDER CREEK

086052003, Linn, IA

Built 2003 Load: 57.9 t ADT: 20

LINN-DELA RD

Fair

Over: BUFFALO CREEK

086060401, Linn, IA

Built 2000 Load: 57.9 t ADT: 97

NUGENTS RD

Fair

Over: BUFFALO CREEK

42.26679783, -91.50518462, Linn, IA

Built 2015 Load: 57.9 t ADT: 49

SEVEN HILLS RD

Fair

Over: WASTON CREEK

086061901, Linn, IA

Built 2004 Load: 57.9 t ADT: 49

RED SCHOOL RD

Fair

Over: HEATONS CREEK

086062604, Linn, IA

Built 1996 Load: 57.9 t ADT: 29

SUTTONRD.

Fair

Over: JUSTINS CREEK

086062902, Linn, IA

Built 1998 Load: 57.9 t ADT: 59

BLODGETT RD

Fair

Over: TRIB TO JUSTINS CREEK

086063007, Linn, IA

Built 2005 Load: 57.9 t ADT: 29

LINN BUCHAN RD

Fair

Over: WALTONS CREEK

086070101, Linn, IA

Built 1990 Load: 57.9 t ADT: 29

BETTYS GROVE RD

Fair

Over: EAST BLUE CREEK

086081006, Linn, IA

Built 1988 Load: 57.9 t ADT: 128

WILEY RD

Fair

Over: E. BLUE CREEK

086082103, Linn, IA

Built 1990 Load: 57.9 t ADT: 128

LOCAL

Fair

Over: CATTLE RUN CREEK

082053503, Linn, IA

Built 1993 Load: 57.9 t ADT: 71

E. OTTER RE.

Fair

Over: WEASEL CREEK

084070504, Linn, IA

Built 1997 Load: 57.9 t ADT: 69

BARRET RD

Fair

Over: EAST INDIAN CREEK

085063404, Linn, IA

Built 2000 Load: 57.9 t ADT: 10

HUTCHINSON RD

Fair

Over: HEATON CREEK

086061601, Linn, IA

Built 2012 Load: 57.9 t ADT: 108

VALLEY FARM RD

Fair

Over: HEATONS CREEK

086061604, Linn, IA

Built 2012 Load: 57.9 t ADT: 98

ROGERS CR RD

Fair

Over: ROGERS CR

000000000, Linn, IA

Built 1989 Load: 58.0 t ADT: 94

US 63 SB

Fair

Over: FUDGE CREEK

4.3 mi. S of Jct. IA 137, Wapello, IA

Built 1997 Load: 58.0 t ADT: 4,950

BASSWOOD AVE

Fair

Over: ROBERTS CREEK

095061502, Clayton, IA

Built 2002 Load: 58.1 t ADT: 668

IA 149

Fair

Over: ENGLISH CREEK

0.2 mi. S of Jct. SR F67, Iowa, IA

Built 1987 Load: 58.3 t ADT: 1,840

JORDANS GROV RD

Fair

Over: HEATONS CREEK

085060104, Linn, IA

Built 2002 Load: 58.3 t ADT: 442

AIRPORT RD.

Fair

Over: SMALL STREAM

085141102, Tama, IA

Built 2005 Load: 58.3 t ADT: 11

FM

Fair

Over: UNNAMED CREEK

084360702, Carroll, IA

Built 1971 Load: 58.6 t ADT: 728

FM U AVE

Fair

Over: BRANCH LITTLE SIOUX

093390804, Cherokee, IA

Built 1966 Load: 59.0 t ADT: 131

R38 500TH AVE

Fair

Over: CLEAR CREEK

084243106, Story, IA

Built 1969 Load: 59.2 t ADT: 2,712

FM

Fair

Over: DRAINAGE

075282205, Madison, IA

Built 1980 Load: 59.4 t ADT: 100

LOCAL

Fair

Over: SMALL STREAM

078160405, Poweshiek, IA

Built 1987 Load: 59.4 t ADT: 15

Showing 8,801-8,850 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.