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

Fair

Over: NORTH ENGLISH RIVER

079132308, Poweshiek, IA

Built 1987 Load: 35.3 t ADT: 20

FM

Fair

Over: SUN VALLEY CREEK

070302503, Ringgold, IA

Built 1994 Load: 35.3 t ADT: 190

FM

Fair

Over: NO NAME CREEK

096433404, Sioux, IA

Built 1966 Load: 35.3 t ADT: 270

FM

Fair

Over: NO NAME CREEK

097481501, Sioux, IA

Built 1966 Load: 35.3 t ADT: 789

LOCAL

Fair

Over: NINE MILE RUN

075303202, Adair, IA

Built 1974 Load: 35.4 t ADT: 46

LOCAL

Fair

Over: STREAM

084120402, Benton, IA

Built 1999 Load: 35.4 t ADT: 11

LOCAL

Fair

Over: BIG CREEK

083261201, Boone, IA

Built 1915 Load: 35.4 t ADT: 50

LOCAL

Fair

Over: SMALL

080043402, Cedar, IA

Built 1979 Load: 35.4 t ADT: 35

200TH AVE

Fair

Over: DRAINAGE DITCH #10

082E22302, Clinton, IA

Built 1984 Load: 35.4 t ADT: 60

NOBLE AVE

Fair

Over: SPRING CREEK

097121704, Howard, IA

Built 1941 Load: 35.4 t ADT: 11

340TH

Fair

Over: SMALL STREAM

097160401, Mitchell, IA

Built 1974 Load: 35.4 t ADT: 33

MARCH AVE

Fair

Over: SPRING CREEK

097161802, Mitchell, IA

Built 1966 Load: 35.4 t ADT: 177

UNDERWOOD AVE

Fair

Over: CREEK

098151602, Mitchell, IA

Built 1975 Load: 35.4 t ADT: 59

ECHO AVE

Fair

Over: CREEK

100182304, Mitchell, IA

Built 1989 Load: 35.4 t ADT: 25

FM-150TH STREET

Fair

Over: MIDDLE NODAWAY RIVER

073343201, Adams, IA

Built 1984 Load: 35.5 t ADT: 45

ASHLEY RD

Fair

Over: TRIB TO CEDAR RIVER

87-11-07-03-20, Black Hawk, IA

Built 1946 Load: 35.5 t ADT: 44

FM

Fair

Over: SMALL STREAM

096132904, Chickasaw, IA

Built 1984 Load: 35.5 t ADT: 992

190TH ST.

Fair

Over: SMALL STREAM

082E51904, Clinton, IA

Built 1976 Load: 35.5 t ADT: 26

FM

Fair

Over: N TIMBER CREEK

083181904, Marshall, IA

Built 1973 Load: 35.5 t ADT: 108

FM

Fair

Over: CROW CREEK

082423004, Monona, IA

Built 1955 Load: 35.5 t ADT: 20

US 71

Fair

Over: FULTONS CREEK

3.4 mi. N of jct. US 34, Montgomery, IA

Built 1972 Load: 35.5 t ADT: 1,390

690TH AVE

Fair

Over: DYE CREEK

083210502, Story, IA

Built 1998 Load: 35.5 t ADT: 45

190TH ST

Fair

Over: CRANE CREEK

092122001, Bremer, IA

Built 1981 Load: 35.6 t ADT: 589

FM

Fair

Over: BUCK CREEK

090101801, Buchanan, IA

Built 1980 Load: 35.6 t ADT: 1,493

N 20TH ST(PROP)

Fair

Over: WILLOW CREEK

096210700, Cerro Gordo, IA

Built 1994 Load: 35.6 t ADT: 829

280TH ST

Fair

Over: STREAM

097351001, Clay, IA

Built 2000 Load: 35.6 t ADT: 60

290TH AVE

Fair

Over: SUGAR CREEK

083E40502, Clinton, IA

Built 1987 Load: 35.6 t ADT: 45

LOC FIREFLY RD

Fair

Over: SMALL STREAM

089060106, Delaware, IA

Built 1986 Load: 35.6 t ADT: 59

LOC 150TH AVE

Fair

Over: SMALL STREAM

090060102, Delaware, IA

Built 1981 Load: 35.6 t ADT: 39

LOCAL

Fair

Over: CROOKED CREEK

073050604, Henry, IA

Built 1988 Load: 35.6 t ADT: 80

US 151 NB

Fair

Over: WAPSIPINICON RIVER

1.4 mi. S of Jct. IA 64, Jones, IA

Built 2002 Load: 35.6 t ADT: 7,200

LOCAL

Fair

Over: STREAM

076131103, Keokuk, IA

Built 1969 Load: 35.6 t ADT: 60

LOCAL

Fair

Over: CREEK

067051208, Lee, IA

Built 1961 Load: 35.6 t ADT: 530

LEWIS ACCESS RD

Fair

Over: CEDAR RIVER

085082004, Linn, IA

Built 1961 Load: 35.6 t ADT: 1,866

EB US 30

Fair

Over: OVER CIC RR SPUR

0.8 mi. W of E Jct US 218, Linn, IA

Built 1980 Load: 35.6 t ADT: 15,750

IA 14

Fair

Over: WOLF CREEK

2.5 mi. S OF Jct. SR H50, Lucas, IA

Built 2006 Load: 35.6 t ADT: 1,490

LOCAL

Fair

Over: STREAM

076212501, Marion, IA

Built 2000 Load: 35.6 t ADT: 35

IA 10

Fair

Over: DRY RUN

0.2 mi. W of W jct. US 59, O'Brien, IA

Built 1969 Load: 35.6 t ADT: 1,610

O AVENUE

Fair

Over: EAST TARKIO RIVER

070371004, Page, IA

Built 1993 Load: 35.6 t ADT: 668

EB I-80

Fair

Over: KEG CREEK

0.8 MI. E OF JCT. SR L66, Pottawattamie, IA

Built 1966 Load: 35.6 t ADT: 13,200

BEECHNUT ROAD

Fair

Over: MIDDLE SILVER CREEK

074422401, Pottawattamie, IA

Built 1990 Load: 35.6 t ADT: 60

FM-295TH STREET

Fair

Over: KEG CREEK

076422504, Pottawattamie, IA

Built 1981 Load: 35.6 t ADT: 60

SB US 61

Fair

Over: WAPSIPINICON RIVER

2.4 mi. N of S.R. F33, Scott, IA

Built 1981 Load: 35.6 t ADT: 8,800

IA 44

Fair

Over: WEST NISHNABOTNA RIVER

1.3 MI. E OF Jct. U.S. 59, Shelby, IA

Built 1978 Load: 35.6 t ADT: 3,960

WB US 30

Fair

Over: OVER UP RR

0.1 MILE W OF JCT SR S14, Story, IA

Built 1963 Load: 35.6 t ADT: 7,900

LOCAL

Fair

Over: EAST 102 RIVER

068342611, Taylor, IA

Built 1993 Load: 35.6 t ADT: 488

LOCAL

Fair

Over: CREEK

069332402, Taylor, IA

Built 1961 Load: 35.6 t ADT: 5

LOCAL

Fair

Over: SAND CREEK

071283203, Union, IA

Built 1984 Load: 35.6 t ADT: 21

FM

Fair

Over: CROOKED CREEK

074071606, Washington, IA

Built 1940 Load: 35.6 t ADT: 1,720

RACCOON

Fair

Over: ELM RUN CR

070213101, Wayne, IA

Built 1951 Load: 35.6 t ADT: 50

Showing 7,601-7,650 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.