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

Good

Over: LITTLE SOAP CREEK

071142204, Wapello, IA

Built 2002 Load: 52.6 t ADT: 120

IA 1 & IA 78

Good

Over: HONEY CREEK

0.7 mi. W of SR W-21, Washington, IA

Built 1991 Load: 52.6 t ADT: 1,520

LOCAL

Good

Over: OTTER CREEK

093252202, Wright, IA

Built 1995 Load: 52.6 t ADT: 31

FM

Good

Over: NINE MILE RUN

075303408, Adair, IA

Built 2003 Load: 52.7 t ADT: 29

FM

Good

Over: GRAND RIVER

075303503, Adair, IA

Built 1995 Load: 52.7 t ADT: 26

LOCAL

Good

Over: MIDDLE NODAWAY RIVER

075322105, Adair, IA

Built 1995 Load: 52.7 t ADT: 51

SWEBAKKEN RD

Good

Over: PAINT CREEK

097041605, Allamakee, IA

Built 2004 Load: 52.7 t ADT: 80

LOCAL

Good

Over: WATERLOO CREEK

100060902, Allamakee, IA

Built 2006 Load: 52.7 t ADT: 25

FM

Good

Over: COOPER CREEK

068180301, Appanoose, IA

Built 2001 Load: 52.7 t ADT: 90

FM

Good

Over: N SHOAL CREEK

068192504, Appanoose, IA

Built 2002 Load: 52.7 t ADT: 70

FM 265TH ST

Good

Over: SHELL ROCK RVR OVERFLOW

091142805, Bremer, IA

Built 2001 Load: 52.7 t ADT: 88

120TH ST

Good

Over: LITTLE WAPSIPINICON RVR

093111303, Bremer, IA

Built 2003 Load: 52.7 t ADT: 69

340TH

Good

Over: ROSE CREEK

097200101, Cerro Gordo, IA

Built 2002 Load: 52.7 t ADT: 41

LOCAL- 600TH ST

Good

Over: SILVER CREEK

090400503, Cherokee, IA

Built 1992 Load: 52.7 t ADT: 30

P AVE

Good

Over: SILVER CREEK

090401002, Cherokee, IA

Built 2006 Load: 52.7 t ADT: 34

LOCAL Y AVE

Good

Over: MAPLE RIVER

091390102, Cherokee, IA

Built 2001 Load: 52.7 t ADT: 26

LOCAL

Good

Over: BUCK CREEK

082390701, Crawford, IA

Built 2007 Load: 52.7 t ADT: 26

LOCAL

Good

Over: EAST BOYER RIVER

084372402, Crawford, IA

Built 2006 Load: 52.7 t ADT: 91

FM

Good

Over: BEAVER CREEK

085401002, Crawford, IA

Built 2006 Load: 52.7 t ADT: 26

LOCAL

Good

Over: BEE CREEK

070260301, Decatur, IA

Built 1993 Load: 52.7 t ADT: 20

LOCAL 190 ST

Good

Over: PLUM CREEK

089042408, Delaware, IA

Built 1996 Load: 52.7 t ADT: 70

330 AVENUE

Good

Over: DEER CREEK

070411004, Fremont, IA

Built 2002 Load: 52.7 t ADT: 264

210 TH

Good

Over: STREAM

084303201, Greene, IA

Built 2002 Load: 52.7 t ADT: 72

150 TH

Good

Over: HARDIN CREEK

085313401, Greene, IA

Built 1994 Load: 52.7 t ADT: 15

LOCAL

Good

Over: MOSQUITO CREEK

081303601, Guthrie, IA

Built 1993 Load: 52.7 t ADT: 15

1060 PALM AVE

Good

Over: WEST BRANCH IA RIVER

094243402, Hancock, IA

Built 2007 Load: 52.7 t ADT: 35

LOCAL

Good

Over: PRAIRIE CREEK

093271101, Humboldt, IA

Built 2003 Load: 52.7 t ADT: 11

JUNIPER AVE

Good

Over: LOTTS CREEK

093290304, Humboldt, IA

Built 1996 Load: 52.7 t ADT: 20

LOCAL

Good

Over: BATTLE CREEK

087412301, Ida, IA

Built 1994 Load: 52.7 t ADT: 30

20TH AVE

Good

Over: BEAR CREEK

084013602, Jones, IA

Built 1991 Load: 52.7 t ADT: 25

ROCK RD

Good

Over: CLINE CREEK

086030903, Jones, IA

Built 2002 Load: 52.7 t ADT: 108

LOCAL

Good

Over: STREAM

074102304, Keokuk, IA

Built 2005 Load: 52.7 t ADT: 15

FM

Good

Over: STREAM

075120902, Keokuk, IA

Built 2001 Load: 52.7 t ADT: 70

LOC 167TH AVE

Good

Over: BUFFALO CREEK

097281006, Kossuth, IA

Built 2001 Load: 52.7 t ADT: 30

LOCAL

Good

Over: SUGAR CREEK

067061803, Lee, IA

Built 1999 Load: 52.7 t ADT: 40

LOCAL

Good

Over: SUGAR CREEK

069062607, Lee, IA

Built 1996 Load: 52.7 t ADT: 60

LOCAL

Good

Over: SOUTH RIVER

074263404, Madison, IA

Built 1999 Load: 52.7 t ADT: 34

LOCAL RD

Good

Over: TOM CREEK

077282204, Madison, IA

Built 1994 Load: 52.7 t ADT: 50

FM

Good

Over: HICORY CREEK

074191907, Marion, IA

Built 2004 Load: 52.7 t ADT: 45

JESSUP AVE

Good

Over: LINN CR

083190302, Marshall, IA

Built 2000 Load: 52.7 t ADT: 62

FM.RD T-41

Good

Over: MID.AVERY CREEK

072162104, Monroe, IA

Built 1994 Load: 52.7 t ADT: 90

LOCAL

Good

Over: MILLER CREEK

072170203, Monroe, IA

Built 1997 Load: 52.7 t ADT: 11

LOCAL

Good

Over: INDIAN CREEK

072390801, Montgomery, IA

Built 1994 Load: 52.7 t ADT: 26

LOCAL

Good

Over: WAPSINONOC CREEK

077041103, Muscatine, IA

Built 2006 Load: 52.7 t ADT: 30

LOCAL

Good

Over: MUD CREEK

078021204, Muscatine, IA

Built 1996 Load: 52.7 t ADT: 166

105TH STREET

Good

Over: STREAM

070380203, Page, IA

Built 2005 Load: 52.7 t ADT: 26

280TH ST

Good

Over: JOHN'S CREEK

090440101, Plymouth, IA

Built 1992 Load: 52.7 t ADT: 5

300TH ST

Good

Over: PERRY CREEK

090471503, Plymouth, IA

Built 1991 Load: 52.7 t ADT: 71

308TH ST

Good

Over: W BR PERRY CREEK

090471603, Plymouth, IA

Built 1998 Load: 52.7 t ADT: 20

270TH ST

Good

Over: CLEAR CREEK

091443501, Plymouth, IA

Built 1991 Load: 52.7 t ADT: 26

Showing 15,951-16,000 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.