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

E REINBECK RD

Good

Over: MUD CREEK

87-12-29-01-10, Black Hawk, IA

Built 1983 Load: 37.1 t ADT: 11

NB US 218

Good

Over: OVER CC & P RR

0.5 mi. N of Jct. IA 57, Black Hawk, IA

Built 1995 Load: 37.1 t ADT: 8,850

160TH ST

Good

Over: CREEK

0921105, Bremer, IA

Built 1997 Load: 37.1 t ADT: 20

310TH ST

Good

Over: WAPSINONOC CREEK

079041901, Cedar, IA

Built 1992 Load: 37.1 t ADT: 130

TAYLOR AVE

Good

Over: ROCK CREEK

081012902, Cedar, IA

Built 1991 Load: 37.1 t ADT: 34

LOCAL-510TH ST

Good

Over: SMALL CREEK

092392101, Cherokee, IA

Built 2010 Load: 37.1 t ADT: 20

LOCAL

Good

Over: WAPSIPINICON RIVER

095140102, Chickasaw, IA

Built 2001 Load: 37.1 t ADT: 104

LOCAL

Good

Over: EAST WAPSIPINICON RIVER

096123102, Chickasaw, IA

Built 1989 Load: 37.1 t ADT: 157

LOCAL

Good

Over: PARADISE CREEK

082400305, Crawford, IA

Built 1988 Load: 37.1 t ADT: 113

COUNTY ROAD

Good

Over: WALNUT CREEK

079261502, Dallas, IA

Built 1988 Load: 37.1 t ADT: 51

350 AVENUE

Good

Over: MILL CREEK

067411402, Fremont, IA

Built 1987 Load: 37.1 t ADT: 15

LOC 200TH AVE

Good

Over: DD #2 & 36

097272902, Kossuth, IA

Built 1991 Load: 37.1 t ADT: 62

LOCAL

Good

Over: SMALL STREAM

075050104, Louisa, IA

Built 1997 Load: 37.1 t ADT: 82

LOCAL

Good

Over: SMALL STREAM

076053603, Louisa, IA

Built 1991 Load: 37.1 t ADT: 35

LOCAL

Good

Over: STREAM

094313302, Palo Alto, IA

Built 1989 Load: 37.1 t ADT: 11

LOCAL

Good

Over: CYLINDER CREEK

096311901, Palo Alto, IA

Built 1992 Load: 37.1 t ADT: 31

LOCAL

Good

Over: JACK CREEK

097320604, Palo Alto, IA

Built 1990 Load: 37.1 t ADT: 26

LOCAL

Good

Over: RACOON RIVER

087362401, Sac, IA

Built 1992 Load: 37.1 t ADT: 26

ST ANNES RD

Good

Over: GLYNNS CREEK

080E42001, Scott, IA

Built 1992 Load: 37.1 t ADT: 660

LOCAL

Good

Over: MIDDLE 102 RIVER

069343401, Taylor, IA

Built 1992 Load: 37.1 t ADT: 50

FM

Good

Over: NODAWAY CREEK

076322201, Adair, IA

Built 2006 Load: 37.2 t ADT: 60

FM

Good

Over: INDIAN CREEK

079362202, Audubon, IA

Built 1996 Load: 37.2 t ADT: 45

HAMMOND AVE

Good

Over: SMALL STREAM

CITY CULVERT NO. 50C, Black Hawk, IA

Built 1991 Load: 37.2 t ADT: 6,813

BISHOP RD

Good

Over: CREEK

091141704, Bremer, IA

Built 2018 Load: 37.2 t ADT: 11

210TH ST

Good

Over: QUARTER SECTION RUN

092133403, Bremer, IA

Built 1991 Load: 37.2 t ADT: 44

C13

Good

Over: FLOOD CREEK

093161101, Butler, IA

Built 2002 Load: 37.2 t ADT: 727

VAIL AVE

Good

Over: SMALL STREAM

093151004, Butler, IA

Built 2000 Load: 37.2 t ADT: 10

LOCAL

Good

Over: BRUSHY FORK CREEK

082350201, Carroll, IA

Built 1991 Load: 37.2 t ADT: 71

LOCAL

Good

Over: FIELD STREAM

083342803, Carroll, IA

Built 1998 Load: 37.2 t ADT: 89

LOCAL - MEMPHIS

Good

Over: WATERWAY

075340601, Cass, IA

Built 1991 Load: 37.2 t ADT: 21

LOCAL/GRT RIVER

Good

Over: NISHNABOTNA RIVER

077362704, Cass, IA

Built 1991 Load: 37.2 t ADT: 30

WARBLER

Good

Over: LITTLE LIME CREEK

096192602, Cerro Gordo, IA

Built 2001 Load: 37.2 t ADT: 47

LOCAL-510TH ST

Good

Over: MAPLE CREEK

092392201, Cherokee, IA

Built 2010 Load: 37.2 t ADT: 26

LOCAL

Good

Over: BR E WAPSIPINICON RIVER

094122101, Chickasaw, IA

Built 1990 Load: 37.2 t ADT: 30

FM

Good

Over: LITTLE TURKEY CREEK

097111901, Chickasaw, IA

Built 2004 Load: 37.2 t ADT: 157

FM

Good

Over: BRANCH ELK CREEK

097132202, Chickasaw, IA

Built 1998 Load: 37.2 t ADT: 29

300TH ST

Good

Over: LITTLE SIOUX RIVER

097372001, Clay, IA

Built 1996 Load: 37.2 t ADT: 11

LOCAL

Good

Over: HANNAH CREEK

084371001, Crawford, IA

Built 1991 Load: 37.2 t ADT: 62

FM

Good

Over: BEAMAN CREEK

085370402, Crawford, IA

Built 1988 Load: 37.2 t ADT: 45

LOCAL

Good

Over: BEAVER CREEK

081270702, Dallas, IA

Built 2004 Load: 37.2 t ADT: 103

ECHO AVE

Good

Over: TRIB FOX RIVER

069152608, Davis, IA

Built 2002 Load: 37.2 t ADT: 50

LOCAL

Good

Over: DRY RUN CREEK

094152102, Floyd, IA

Built 1991 Load: 37.2 t ADT: 49

FM

Good

Over: BLACKHAWK CREEK ,BRANCH

087171002, Grundy, IA

Built 1988 Load: 37.2 t ADT: 128

FM-335TH ST

Good

Over: PIGEON CREEK

078423401, Harrison, IA

Built 1991 Load: 37.2 t ADT: 79

LOC VIENNA AVE

Good

Over: PICAYUNE CREEK

080411204, Harrison, IA

Built 2006 Load: 37.2 t ADT: 26

FM-ROBIN AVE

Good

Over: TURKEY RIVER

098120102, Howard, IA

Built 1994 Load: 37.2 t ADT: 422

LOCAL

Good

Over: ELK CREEK

087390602, Ida, IA

Built 1992 Load: 37.2 t ADT: 41

LOCAL RD

Good

Over: BATTLE CREEK

088412401, Ida, IA

Built 1992 Load: 37.2 t ADT: 35

LOCAL

Good

Over: BRIDGE CREEK

076123601, Keokuk, IA

Built 1992 Load: 37.2 t ADT: 45

LOCAL

Good

Over: LOST CREEK

068040305, Lee, IA

Built 1995 Load: 37.2 t ADT: 150

Showing 13,351-13,400 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.