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: DRAINAGE DITCH

091272301, Humboldt, IA

Built 2007 Load: 45.4 t ADT: 20

SE 680TH ST

Good

Over: RICHEY CR

077053501, Johnson, IA

Built 1996 Load: 45.4 t ADT: 60

95TH AVE.

Good

Over: MINERAL CREEK

085023404, Jones, IA

Built 2006 Load: 45.4 t ADT: 10

LOC 120TH ST

Good

Over: HINE CREEK

094293001, Kossuth, IA

Built 1989 Load: 45.4 t ADT: 26

LOC 40TH AVE

Good

Over: LOTTS CREEK

096303402, Kossuth, IA

Built 2007 Load: 45.4 t ADT: 30

LOC 100TH AVE

Good

Over: D.D.#69

097290302, Kossuth, IA

Built 1993 Load: 45.4 t ADT: 21

LOC 300TH ST

Good

Over: BLACK CAT CREEK

097302501, Kossuth, IA

Built 1989 Load: 45.4 t ADT: 11

FM 390TH ST

Good

Over: MUD CREEK

098291001, Kossuth, IA

Built 2003 Load: 45.4 t ADT: 100

LOC 410TH ST

Good

Over: D.D. #80

099283401, Kossuth, IA

Built 1996 Load: 45.4 t ADT: 26

LOC 170TH ST

Good

Over: D.D. #80

099283502, Kossuth, IA

Built 1996 Load: 45.4 t ADT: 35

LOC 410TH ST

Good

Over: UNION SLOUGH DITCH

099283601, Kossuth, IA

Built 1991 Load: 45.4 t ADT: 50

US 65

Good

Over: HAMILTON CREEK

1.6 MI. N OF SR H50, Lucas, IA

Built 1991 Load: 45.4 t ADT: 1,260

FM

Good

Over: JOHNSON CREEK

098440501, Lyon, IA

Built 2006 Load: 45.4 t ADT: 1,168

P71 CLARK TOWER RD

Good

Over: N FORK CLANTON CREEK

074111200, Madison, IA

Built 2022 Load: 45.4 t ADT: 278

VIRGINIA ST

Good

Over: UP RR

074213501, Marion, IA

Built 2011 Load: 45.4 t ADT: 35

LOCAL

Good

Over: CLEAR CREEK

083203002, Marshall, IA

Built 1993 Load: 45.4 t ADT: 45

FM

Good

Over: LOCAL CREEK

071161203, Monroe, IA

Built 2006 Load: 45.4 t ADT: 80

FM

Good

Over: CREEK

078030501, Muscatine, IA

Built 2005 Load: 45.4 t ADT: 70

NEST AVE

Good

Over: LITTLE FLOYD RIVER

096420902, O'Brien, IA

Built 2012 Load: 45.4 t ADT: 46

FM

Good

Over: CREEK

098423102, Osceola, IA

Built 1994 Load: 45.4 t ADT: 110

J53 280TH STREET

Good

Over: BUCHANAN CREEK

067361101, Page, IA

Built 2023 Load: 45.4 t ADT: 71

LOCAL

Good

Over: PRAIRIE CREEK

094312403, Palo Alto, IA

Built 1990 Load: 45.4 t ADT: 73

FM

Good

Over: DD 84

094342302, Palo Alto, IA

Built 2002 Load: 45.4 t ADT: 1,008

310TH ST

Good

Over: MUDDY CREEK

090452101, Plymouth, IA

Built 1999 Load: 45.4 t ADT: 34

250TH ST

Good

Over: MUD CREEK

091442001, Plymouth, IA

Built 2000 Load: 45.4 t ADT: 190

IDEAL ROAD

Good

Over: DRAINAGE

091461701, Plymouth, IA

Built 2003 Load: 45.4 t ADT: 20

FM

Good

Over: PERRY CREEK

091471201, Plymouth, IA

Built 1995 Load: 45.4 t ADT: 259

NOBLE AVE

Good

Over: PLYMOUTH CREEK

092441902, Plymouth, IA

Built 2000 Load: 45.4 t ADT: 80

LAKE AVE

Good

Over: WEST FORK FLOYD RIVER

093450704, Plymouth, IA

Built 1999 Load: 45.4 t ADT: 26

130TH ST

Good

Over: MINK CREEK

093462101, Plymouth, IA

Built 2002 Load: 45.4 t ADT: 60

FM

Good

Over: NO LIZARD CK DD #77

092321502, Pocahontas, IA

Built 2005 Load: 45.4 t ADT: 309

FM

Good

Over: PILOT CK DD #63

093322202, Pocahontas, IA

Built 2006 Load: 45.4 t ADT: 270

NW 72ND PLACE

Good

Over: CREEK

080243409, Polk, IA

Built 2015 Load: 45.4 t ADT: 338

LOCAL

Good

Over: STREAM

068283602, Ringgold, IA

Built 1999 Load: 45.4 t ADT: 20

FM

Good

Over: CROOKED CREEK

069301301, Ringgold, IA

Built 2001 Load: 45.4 t ADT: 120

241ST ST

Good

Over: HICKORY CREEK

079E21005, Scott, IA

Built 1993 Load: 45.4 t ADT: 140

ST ANNES RD

Good

Over: CREEK

080E42101, Scott, IA

Built 2003 Load: 45.4 t ADT: 660

K30 EAGLE AVE

Good

Over: INDIAN CREEK

094460802, Sioux, IA

Built 2006 Load: 45.4 t ADT: 1,555

FM

Good

Over: BARNES CREEK

094432402, Sioux, IA

Built 1993 Load: 45.4 t ADT: 345

FM

Good

Over: STREAM

094440902, Sioux, IA

Built 1998 Load: 45.4 t ADT: 2,930

LOCAL

Good

Over: ORANGE CITY SLOUGH

094452201, Sioux, IA

Built 1996 Load: 45.4 t ADT: 40

FM

Good

Over: CREEK

094453401, Sioux, IA

Built 2007 Load: 45.4 t ADT: 50

LOCAL

Good

Over: SMALL STREAM

095450201, Sioux, IA

Built 1994 Load: 45.4 t ADT: 40

FM

Good

Over: CREEK

095452001, Sioux, IA

Built 1999 Load: 45.4 t ADT: 1,236

FM

Good

Over: CREEK

095462902, Sioux, IA

Built 2003 Load: 45.4 t ADT: 957

MARSH AVE

Good

Over: NO NAME CREEK

096430102, Sioux, IA

Built 2000 Load: 45.4 t ADT: 30

LOCAL

Good

Over: SMALL STREAM

096441002, Sioux, IA

Built 2007 Load: 45.4 t ADT: 30

FM

Good

Over: STREAM

097430801, Sioux, IA

Built 1995 Load: 45.4 t ADT: 619

B AVE

Good

Over: SUGAR CREEK

084162002, Tama, IA

Built 2006 Load: 45.4 t ADT: 20

LOCAL

Good

Over: BRANCH WOLF CREEK

085141401, Tama, IA

Built 2003 Load: 45.4 t ADT: 128

Showing 15,201-15,250 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.