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

LOCAL

Good

Over: WEST CREEK

075242201, Warren, IA

Built 1987 Load: 33.2 t ADT: 72

W 42

Good

Over: CREEK

.4 mi south of Valdres Rd, Winneshiek, IA

Built 2013 Load: 33.2 t ADT: 933

400TH ST

Good

Over: STREAM

070190403, Appanoose, IA

Built 2021 Load: 33.3 t ADT: 21

KLINE RD

Good

Over: TRIB TO WOLF CREEK

87-12-34-02-10, Black Hawk, IA

Built 2002 Load: 33.3 t ADT: 34

W QUARRY RD

Good

Over: TRIB TO MILLER CREEK

87-13-16-01-10, Black Hawk, IA

Built 2002 Load: 33.3 t ADT: 15

W REINBECK RD

Good

Over: MILLER CREEK

87-13-28-01-20, Black Hawk, IA

Built 2002 Load: 33.3 t ADT: 11

KIMBALL AVE

Good

Over: TRIB TO MILLER CREEK

87-13-34-02-10, Black Hawk, IA

Built 2002 Load: 33.3 t ADT: 29

BAKER RD

Good

Over: CAMP CREEK

89-11-13-04-10, Black Hawk, IA

Built 2002 Load: 33.3 t ADT: 10

LOCAL - TROY

Good

Over: SMALL STREAM

074370703, Cass, IA

Built 1986 Load: 33.3 t ADT: 51

LOCAL - 770TH

Good

Over: WATERWAY

077341306, Cass, IA

Built 1985 Load: 33.3 t ADT: 26

NB I-35

Good

Over: BEAVER DAM CREEK

0.6 MI. S OF JCT. SR B43, Cerro Gordo, IA

Built 1972 Load: 33.3 t ADT: 8,900

130TH AVE

Good

Over: SMALL STREAM

082E12806, Clinton, IA

Built 1987 Load: 33.3 t ADT: 460

120TH ST.

Good

Over: SIMMONS CREEK

083E51503, Clinton, IA

Built 1997 Load: 33.3 t ADT: 21

LOCAL

Good

Over: OTTER CREEK

084391201, Crawford, IA

Built 2009 Load: 33.3 t ADT: 30

FM

Good

Over: KILGORE CREEK

068253503, Decatur, IA

Built 1986 Load: 33.3 t ADT: 29

215TH ST

Good

Over: MCGRUDER CREEK

069253303, Decatur, IA

Built 2016 Load: 33.3 t ADT: 110

LOCAL

Good

Over: CURREN BRANCH

088012704, Dubuque, IA

Built 1986 Load: 33.3 t ADT: 26

180TH ST

Good

Over: PICAYUNE CREEK

080421305, Harrison, IA

Built 1981 Load: 33.3 t ADT: 79

FM

Good

Over: PAINTER CREEK

067051608, Lee, IA

Built 1987 Load: 33.3 t ADT: 60

FM

Good

Over: SIMMONS CREEK

085431406, Monona, IA

Built 1987 Load: 33.3 t ADT: 71

FM-210TH STREET

Good

Over: MIDDLE NODAWAY RIVER

072363603, Montgomery, IA

Built 2004 Load: 33.3 t ADT: 100

60TH ST

Good

Over: JORDON CREEK

P60800590, Polk, IA

Built 1992 Load: 33.3 t ADT: 13,750

LOCAL

Good

Over: INDIAN CREEK

074381901, Pottawattamie, IA

Built 1987 Load: 33.3 t ADT: 20

LOCAL

Good

Over: BIGALK CREEK

100101804, Winneshiek, IA

Built 1987 Load: 33.3 t ADT: 25

130TH ST

Good

Over: CREEK

081342001, Audubon, IA

Built 2023 Load: 33.4 t ADT: 21

BURTON RD

Good

Over: TRIB TO CEDAR RIVER

90-13-26-02-10, Black Hawk, IA

Built 2016 Load: 33.4 t ADT: 49

135TH ST

Good

Over: SMALL

082042003, Cedar, IA

Built 2015 Load: 33.4 t ADT: 5

BENSON ST

Good

Over: BRANCH EAST LONG CREEK

071263101, Clarke, IA

Built 2015 Load: 33.4 t ADT: 100

185TH AVE

Good

Over: SMALL STREAM

082E22104, Clinton, IA

Built 1994 Load: 33.4 t ADT: 26

130TH STREET

Good

Over: STREAM

083E22103, Clinton, IA

Built 1962 Load: 33.4 t ADT: 73

JADE AVE

Good

Over: SMALL STREAM

068142702, Davis, IA

Built 2021 Load: 33.4 t ADT: 25

LARK AVE

Good

Over: BUFFALO CREEK

092211202, Franklin, IA

Built 2018 Load: 33.4 t ADT: 41

J18 PLUM CREEK RD

Good

Over: PLUM CREEK

070422004, Fremont, IA

Built 2017 Load: 33.4 t ADT: 289

LOCAL

Good

Over: STREAM

080322904, Guthrie, IA

Built 2011 Load: 33.4 t ADT: 29

FM

Good

Over: DRAINAGE DITCH

079101400, Iowa, IA

Built 2017 Load: 33.4 t ADT: 120

HOLLY AVE

Good

Over: GOSHEN DRAINAGE DITCH

078032002, Muscatine, IA

Built 2023 Load: 33.4 t ADT: 25

LOCAL

Good

Over: MILL CREEK

096413401, O'Brien, IA

Built 1998 Load: 33.4 t ADT: 11

KEY AVE

Good

Over: DRAINAGE

9345310210, Plymouth, IA

Built 2018 Load: 33.4 t ADT: 40

525TH ST

Good

Over: DRAINAGE

074383504, Pottawattamie, IA

Built 2013 Load: 33.4 t ADT: 40

I 74 EB

Good

Over: MISSISSIPPI RIVER

IN BETTENDORF, Scott, IA

Built 2021 Load: 33.4 t ADT: 28,250

FM

Good

Over: SIX MILE CREEK

096462502, Sioux, IA

Built 1982 Load: 33.4 t ADT: 1,337

28TH ST

Good

Over: CHIPPEWA CREEK

071122800, Wapello, IA

Built 2022 Load: 33.4 t ADT: 207

JUNIPER AVE

Good

Over: SMALL STREAM

074082706, Washington, IA

Built 2022 Load: 33.4 t ADT: 40

STATE LINE RD

Good

Over: CREEK

E of 310th Ave, Winneshiek, IA

Built 2015 Load: 33.4 t ADT: 70

LOCAL

Good

Over: STREAM

068162601, Appanoose, IA

Built 1999 Load: 33.5 t ADT: 16

110TH ST

Good

Over: FIELD STREAM

085351201, Carroll, IA

Built 2000 Load: 33.5 t ADT: 89

110TH ST

Good

Over: SMALL STREAM

085351201, Carroll, IA

Built 2000 Load: 33.5 t ADT: 89

LOCAL

Good

Over: CRANE RIVER

096121403, Chickasaw, IA

Built 1982 Load: 33.5 t ADT: 82

US 30 & US 67

Good

Over: OVER UPRR

0.3 mi. E of W Jct. US 67, Clinton, IA

Built 2000 Load: 33.5 t ADT: 17,200

100TH AVENUE

Good

Over: PLUM CREEK

082E11806, Clinton, IA

Built 2002 Load: 33.5 t ADT: 30

Showing 12,401-12,450 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.