State profile · Above median Poor share

Iowa bridge safety

Condition ratings, load ratings, and Poor-condition data for every public highway bridge in Iowa, based on the FHWA National Bridge Inventory.

20,753
Public bridges
36.5%
Good condition
20.0%
Poor condition

Data updated May 2026

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 whose lowest applicable component is rated 0-4

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 - Poor-condition share 66.7%
National avg

Lower is better. Bar maxes at 30% (worst-state ceiling). National average sits at 7.0%.

Condition Distribution

Iowa38.5%40.4%21.1%GoodFairPoor
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 by Poor-condition share (lower share = better)

States are ranked by the share of bridges whose lowest applicable component rating is 4 or below. This describes recorded condition; it does not measure funding effectiveness or live crossing safety. States here sit immediately above and below Iowa on the same metric.

WV

West Virginia

16.02% top marginal rate
Structure
Progressive
Burden @ $100K
$7,679

SD

South Dakota

16.24% top marginal rate
Structure
Progressive
Burden @ $100K
$5,905
Selected

IA

Iowa

20.01% top marginal rate
Structure
Progressive
Burden @ $100K
$20,753

VI

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 the portal's composite display score. Inspection intervals are risk-based under current NBIS rules.

270TH STREET

Poor

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

Poor

Over: MUD CREEK

87-12-15-02-10, Black Hawk, IA

Built 1948 Load: 2.7 t ADT: 11

LOCAL - 700TH

Poor

Over: TRIB TROUBLESOME CREEK

077351402, Cass, IA

Built 1983 Load: 2.7 t ADT: 11

LOCAL - DAYTONA

Poor

Over: BUCK CREEK

077361903, Cass, IA

Built 1980 Load: 2.7 t ADT: 35

100TH ST.

Poor

Over: UNION CREEK

083E20101, Clinton, IA

Built 1900 Load: 2.7 t ADT: 78

All Bridges in Iowa

LOCAL

Poor

Over: FULTON TWP

088300302, Webster, IA

Built 1956 Load: 10.8 t ADT: 35

LOCAL

Poor

Over: STREAM

089431302, Woodbury, IA

Built 1940 Load: 10.8 t ADT: 15

160TH

Poor

Over: BEAVER DAM CREEK

094210101, Cerro Gordo, IA

Built 1913 Load: 10.9 t ADT: 30

LOCAL

Poor

Over: CHARITON CREEK

071242906, Clarke, IA

Built 1971 Load: 10.9 t ADT: 20

LOCAL

Poor

Over: SOLDIER RIVER

085411102, Crawford, IA

Built 1951 Load: 10.9 t ADT: 41

FM

Poor

Over: CEDAR RIVER

097172405, Floyd, IA

Built 1936 Load: 10.9 t ADT: 79

LOCAL

Poor

Over: BOONE RIVER

087261604, Hamilton, IA

Built 1954 Load: 10.9 t ADT: 60

LOCAL

Poor

Over: DR TO HONEY CREEK

071222404, Lucas, IA

Built 1900 Load: 10.9 t ADT: 5

LOCAL

Poor

Over: CREEK

083190603, Marshall, IA

Built 1918 Load: 10.9 t ADT: 30

VALLEY AVE

Poor

Over: CREEK

098151502, Mitchell, IA

Built 1960 Load: 10.9 t ADT: 11

LOCAL

Poor

Over: STREAM

099413302, Osceola, IA

Built 1944 Load: 10.9 t ADT: 21

LOCAL

Poor

Over: SMALL STREAM

088363201, Sac, IA

Built 1900 Load: 10.9 t ADT: 26

E36

Poor

Over: SALT CREEK

084132203, Tama, IA

Built 1959 Load: 10.9 t ADT: 314

FM

Poor

Over: BUTCHER CREEK

077221904, Warren, IA

Built 1952 Load: 10.9 t ADT: 830

LOCAL 570TH ST

Poor

Over: MAPLE RIVER

091392001, Cherokee, IA

Built 1918 Load: 11.0 t ADT: 11

590TH ST

Poor

Over: MAPLE RIVER

091393201, Cherokee, IA

Built 1919 Load: 11.0 t ADT: 30

440TH ST

Poor

Over: CREEK

093391401, Cherokee, IA

Built 1931 Load: 11.0 t ADT: 11

JUNE AVE

Poor

Over: SMALL STREAM

091030710, Clayton, IA

Built 1910 Load: 11.0 t ADT: 21

295TH ST

Poor

Over: STREAM

092051203, Clayton, IA

Built 1910 Load: 11.0 t ADT: 51

LOCAL

Poor

Over: BROWN CREEK

099330603, Emmet, IA

Built 1972 Load: 11.0 t ADT: 34

LOCAL

Poor

Over: SMALL CREEK

096181912, Floyd, IA

Built 1916 Load: 11.0 t ADT: 78

250TH ST

Poor

Over: ALLEN CREEK

079442301, Harrison, IA

Built 1965 Load: 11.0 t ADT: 11

LOCAL

Poor

Over: STREAM

075212402, Marion, IA

Built 1925 Load: 11.0 t ADT: 16

FAWN AVE

Poor

Over: DRAINAGE

092470802, Plymouth, IA

Built 1900 Load: 11.0 t ADT: 30

LOCAL

Poor

Over: SMALL STREAM

089382802, Sac, IA

Built 1931 Load: 11.0 t ADT: 20

150TH ST

Poor

Over: SKUNK RIVER

085233103, Story, IA

Built 1920 Load: 11.0 t ADT: 100

LOCAL

Poor

Over: STREAM

070100504, Van Buren, IA

Built 1968 Load: 11.0 t ADT: 25

FM

Poor

Over: MUDDY CREEK

089450801, Woodbury, IA

Built 1967 Load: 11.0 t ADT: 628

LOCAL

Poor

Over: SMALL STREAM

092162504, Butler, IA

Built 1969 Load: 11.1 t ADT: 51

FM

Poor

Over: WELDON RIVER

069240401, Decatur, IA

Built 1957 Load: 11.1 t ADT: 421

LOCAL

Poor

Over: TRIB S FORK ENG RIVER

077111403, Keokuk, IA

Built 1951 Load: 11.1 t ADT: 26

LOCAL

Poor

Over: JIM CREEK

077291302, Madison, IA

Built 1939 Load: 11.1 t ADT: 11

FM

Poor

Over: NE NORWAY CREEK

083422602, Monona, IA

Built 1949 Load: 11.1 t ADT: 50

LOCAL

Poor

Over: NODAWAY RIVER

072362904, Montgomery, IA

Built 1968 Load: 11.1 t ADT: 20

LOCAL

Poor

Over: LITTLE OCHEYEDAN RIVER

099403302, Osceola, IA

Built 1934 Load: 11.1 t ADT: 21

200TH ST

Poor

Over: W.BRANCH FLOYD RIVER

092462603, Plymouth, IA

Built 1960 Load: 11.1 t ADT: 71

LOCAL

Poor

Over: TRIB TO SPRING CREEK

073130501, Wapello, IA

Built 1950 Load: 11.1 t ADT: 5

LOCAL

Poor

Over: MIDDLE NODAWAY RIVER BR

074330104, Adair, IA

Built 1949 Load: 11.2 t ADT: 15

FM

Poor

Over: WAPSIPINICON RIVER

096140901, Chickasaw, IA

Built 1957 Load: 11.2 t ADT: 501

E 132ND ST S

Poor

Over: SMALL STREAM

078170406, Jasper, IA

Built 1937 Load: 11.2 t ADT: 91

LOCAL

Poor

Over: BURR OAK CREEK

081183401, Jasper, IA

Built 1950 Load: 11.2 t ADT: 30

LOCAL

Poor

Over: N CEDAR CREEK

074192704, Marion, IA

Built 1994 Load: 11.2 t ADT: 11

FM

Poor

Over: SOUTH TIMBER CREEK

083173204, Marshall, IA

Built 1942 Load: 11.2 t ADT: 88

LOCAL

Poor

Over: TIMBER CREEK

083182405, Marshall, IA

Built 1942 Load: 11.2 t ADT: 91

LOCAL

Poor

Over: DRAINAGE

073171906, Monroe, IA

Built 1948 Load: 11.2 t ADT: 20

FIELD ENTRANCE

Poor

Over: DRAINAGE (SDB)

070391402, Page, IA

Built 1900 Load: 11.2 t ADT: 10

LOCAL

Poor

Over: DD6

095340901, Palo Alto, IA

Built 1917 Load: 11.2 t ADT: 11

632ND AVE

Poor

Over: STREAM

082220806, Story, IA

Built 1973 Load: 11.2 t ADT: 60

LOCAL

Poor

Over: SALT CREEK

082130105, Tama, IA

Built 1982 Load: 11.2 t ADT: 11

FM

Poor

Over: MIDDLE PLATTE RIVER

071311601, Union, IA

Built 1952 Load: 11.2 t ADT: 40

Showing 17,751-17,800 of 20,753 bridges

Related

All states → | National rankings → | Understanding conditions → | Retired SD term explained →
Data sourced from the FHWA National Bridge Inventory (NBI), latest released cycle. See our methodology for details. Retrieved and formatted by PlainBridges.

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). Poor condition is an inspection-record category, not a closure or unsafe-to-cross designation. Consult the bridge owner for current status.

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.

Every figure on PlainBridge is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.