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

50TH AVE

Fair

Over: CREEK

080E11406, Scott, IA

Built 1974 Load: 27.9 t ADT: 20

ALBANY AVE.N

Fair

Over: ORANGE CITY SLOUGH

095442804, Sioux, IA

Built 1973 Load: 27.9 t ADT: 3,610

IA 21

Fair

Over: WOLF CREEK

0.4 MILES SOUTH OF D65, Tama, IA

Built 1960 Load: 27.9 t ADT: 2,600

US 34

Fair

Over: TWELVE MILE CREEK

2.4 MI. W OF JCT. U.S.169, Union, IA

Built 1971 Load: 27.9 t ADT: 4,890

LOCAL

Fair

Over: INDIAN CREEK

068100804, Van Buren, IA

Built 1951 Load: 27.9 t ADT: 73

FM

Fair

Over: FOX RIVER

068111704, Van Buren, IA

Built 1984 Load: 27.9 t ADT: 370

LOCAL

Fair

Over: W FORK LITTLE SIOUX R.

087451001, Woodbury, IA

Built 1986 Load: 27.9 t ADT: 45

FM

Fair

Over: DD NO. 83

088311901, Calhoun, IA

Built 1972 Load: 28.0 t ADT: 15

LOCAL

Fair

Over: DD NO 12

089312102, Calhoun, IA

Built 1976 Load: 28.0 t ADT: 60

IA 3

Fair

Over: LITTLE WAPSIPINICON RVR

0.2 mi. W of Jct. SR V68, Fayette, IA

Built 1959 Load: 28.0 t ADT: 1,730

FM 130TH ST

Fair

Over: ALLEN CREEK

081432303, Harrison, IA

Built 1950 Load: 28.0 t ADT: 15

W 130TH ST N

Fair

Over: SMALL STREAM

080210404, Jasper, IA

Built 1996 Load: 28.0 t ADT: 21

US 18

Fair

Over: BIG SIOUX RIVER

at S.DAKOTA BORDER, Lyon, IA

Built 1978 Load: 28.0 t ADT: 2,130

LOCAL RD

Fair

Over: JIM CREEK

077292102, Madison, IA

Built 1991 Load: 28.0 t ADT: 34

IA 330 NB

Fair

Over: NORTH SKUNK RIVER

0.8 mi. N of Jct. SR S-52, Marshall, IA

Built 1969 Load: 28.0 t ADT: 8,300

410TH STREET

Fair

Over: IAIS RR

076401407, Pottawattamie, IA

Built 1950 Load: 28.0 t ADT: 15

EASTERN HILLS D

Fair

Over: STREAM

000000000, Pottawattamie, IA

Built 2005 Load: 28.0 t ADT: 151

FM

Fair

Over: SMALL STREAM

069350704, Taylor, IA

Built 1956 Load: 28.0 t ADT: 79

HAMILTON BLVD

Fair

Over: PERRY CREEK

000000000, Woodbury, IA

Built 1959 Load: 28.0 t ADT: 10,721

LOCAL ROAD

Fair

Over: HONEY CREEK

070180603, Appanoose, IA

Built 1968 Load: 28.1 t ADT: 960

580TH ST

Fair

Over: POWELL CREEK

091373001, Buena Vista, IA

Built 1972 Load: 28.1 t ADT: 429

FM

Fair

Over: SMALL

094133001, Chickasaw, IA

Built 1978 Load: 28.1 t ADT: 20

425TH AVENUE

Fair

Over: ELK RIVER

083E62104, Clinton, IA

Built 1991 Load: 28.1 t ADT: 26

N14 (310TH AVE)

Fair

Over: MUDDY CREEK

099353402, Dickinson, IA

Built 1951 Load: 28.1 t ADT: 1,514

IA 144

Fair

Over: EAST BUTTRICK CREEK

6.7 MI. S OF JCT. IA 175, Greene, IA

Built 1948 Load: 28.1 t ADT: 590

A AVE

Fair

Over: SMALL STREAM

085320602, Greene, IA

Built 1979 Load: 28.1 t ADT: 26

S 52ND AVE E

Fair

Over: SMALL STREAM

079182201, Jasper, IA

Built 1936 Load: 28.1 t ADT: 16

IA 1

Fair

Over: BIG CEDAR CREEK

2.9 MI. S of Jct. US 34, Jefferson, IA

Built 1967 Load: 28.1 t ADT: 2,730

IA 16

Fair

Over: SUGAR CREEK

0.3 MI. W OF JCT. US 218, Lee, IA

Built 1966 Load: 28.1 t ADT: 1,490

ORCHARD AVE

Fair

Over: SILVER CREEK

071411604, Mills, IA

Built 1968 Load: 28.1 t ADT: 11

LCL-DOBNEY AVE

Fair

Over: SILVER CREEK

073421305, Mills, IA

Built 1977 Load: 28.1 t ADT: 100

US 34

Fair

Over: MIDDLE NODAWAY RIVER

3.0 MI. E JCT. US 71, Montgomery, IA

Built 1964 Load: 28.1 t ADT: 2,240

FM

Fair

Over: NISHNABOTNA RIVER

071393603, Montgomery, IA

Built 1972 Load: 28.1 t ADT: 133

LOCAL

Fair

Over: NODAWAY RIVER

073361302, Montgomery, IA

Built 1982 Load: 28.1 t ADT: 50

EASTER LK DR

Fair

Over: BR EASTER LAKE

078233000, Polk, IA

Built 1967 Load: 28.1 t ADT: 4,097

FM-HONEYSUCKLE

Fair

Over: WEST NISHNABOTNA RIVER

075401109, Pottawattamie, IA

Built 1967 Load: 28.1 t ADT: 550

650TH AVE

Fair

Over: RUPPLE CREEK

082221014, Story, IA

Built 1971 Load: 28.1 t ADT: 1,228

170TH ST

Fair

Over: SKUNK RIVER

084230703, Story, IA

Built 1939 Load: 28.1 t ADT: 139

R38/500TH AVE

Fair

Over: ONION CREEK

084243002, Story, IA

Built 1970 Load: 28.1 t ADT: 2,404

LOCAL

Fair

Over: PRAIRIE CREEK

086090703, Benton, IA

Built 1996 Load: 28.2 t ADT: 20

S ORDWAY RD

Fair

Over: POYNER CREEK

89-11-31-02-10, Black Hawk, IA

Built 1977 Load: 28.2 t ADT: 69

NEWELL ST

Fair

Over: BLOWERS CREEK

CITY BRIDGE NO. 30, Black Hawk, IA

Built 1978 Load: 28.2 t ADT: 1,429

FM

Fair

Over: SMALL STREAM

089101007, Buchanan, IA

Built 1965 Load: 28.2 t ADT: 422

FOREST AVE

Fair

Over: SMALL STREAM

092181202, Butler, IA

Built 2011 Load: 28.2 t ADT: 21

OLD US 20

Fair

Over: CAMP CREEK

088342101, Calhoun, IA

Built 1992 Load: 28.2 t ADT: 609

160TH ST

Fair

Over: SMALL

081010403, Cedar, IA

Built 1904 Load: 28.2 t ADT: 5

PARK RD

Fair

Over: ROCK CREEK

081031105, Cedar, IA

Built 1985 Load: 28.2 t ADT: 45

100TH ST

Fair

Over: ELK RIVER

083E60501, Clinton, IA

Built 1950 Load: 28.2 t ADT: 78

FM

Fair

Over: MOSQUITO CREEK

079291503, Dallas, IA

Built 1951 Load: 28.2 t ADT: 278

FM

Fair

Over: BEAVER CREEK

081262904, Dallas, IA

Built 1971 Load: 28.2 t ADT: 490

Showing 5,001-5,050 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.