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

HORNET RD

Poor

Over: BEAR CREEK

092043303, Clayton, IA

Built 1923 Load: 11.7 t ADT: 73

LOCAL 40TH ST

Poor

Over: BEAVER CREEK

090202601, Franklin, IA

Built 1954 Load: 11.7 t ADT: 35

LOCAL

Poor

Over: TIPTON CREEK

087220302, Hardin, IA

Built 1987 Load: 11.7 t ADT: 16

BURLINGHAM RD

Poor

Over: BUFFALO CR

085051401, Linn, IA

Built 1900 Load: 11.7 t ADT: 50

LCL-RAINS AV

Poor

Over: HUNTER BRANCH

071403401, Mills, IA

Built 1950 Load: 11.7 t ADT: 15

LOCAL

Poor

Over: CREEK

070080804, Van Buren, IA

Built 1971 Load: 11.7 t ADT: 16

LOCAL

Poor

Over: CANOE CREEK

099080906, Winneshiek, IA

Built 1924 Load: 11.7 t ADT: 20

LOCAL ROAD

Poor

Over: IOWA RIVER

092242303, Wright, IA

Built 1930 Load: 11.7 t ADT: 21

LOCAL

Poor

Over: PRAIRIE CREEK

082110701, Benton, IA

Built 1974 Load: 11.8 t ADT: 15

LOCAL

Poor

Over: MIDDLE RACCOON RIVER

082340106, Carroll, IA

Built 1951 Load: 11.8 t ADT: 11

FM - 730TH

Poor

Over: ELM CREEK

074340802, Cass, IA

Built 1956 Load: 11.8 t ADT: 45

LOCAL

Poor

Over: CREEK

095132404, Chickasaw, IA

Built 1960 Load: 11.8 t ADT: 73

LOCAL

Poor

Over: DAVISONS CREEK

083172504, Marshall, IA

Built 1951 Load: 11.8 t ADT: 21

LOCAL

Poor

Over: MOSQUITO CREEK

079402903, Shelby, IA

Built 1917 Load: 11.8 t ADT: 35

LOCAL

Poor

Over: PLATTE BRANCH

067321901, Taylor, IA

Built 1900 Load: 11.8 t ADT: 15

240TH STREET

Poor

Over: SAYLINGS CREEK

071321401, Adams, IA

Built 1958 Load: 11.9 t ADT: 26

240TH STREET

Poor

Over: PLATTE RIVER

071321403, Adams, IA

Built 1958 Load: 11.9 t ADT: 34

POPLAR AVENUE

Poor

Over: LONZO CREEK

071333502, Adams, IA

Built 1957 Load: 11.9 t ADT: 50

HOLLY AVENUE

Poor

Over: WEST FORK 102 RIVER

071342104, Adams, IA

Built 1958 Load: 11.9 t ADT: 5

NOTCHWOOD AVE

Poor

Over: STREAM

072331602, Adams, IA

Built 1956 Load: 11.9 t ADT: 40

MULBERRY AVE

Poor

Over: STREAM

072331912, Adams, IA

Built 1962 Load: 11.9 t ADT: 5

DOGWOOD AVENUE

Poor

Over: WILLIAMS CREEK

073351102, Adams, IA

Built 1964 Load: 11.9 t ADT: 5

LOCAL

Poor

Over: DD 65

088322902, Calhoun, IA

Built 1929 Load: 11.9 t ADT: 20

LOCAL - 710TH

Poor

Over: WATERWAY

075352502, Cass, IA

Built 1955 Load: 11.9 t ADT: 11

LOCAL 460TH ST

Poor

Over: GREY CREEK

093402703, Cherokee, IA

Built 1927 Load: 11.9 t ADT: 15

LOCAL 470TH ST

Poor

Over: GREY CREEK

093403403, Cherokee, IA

Built 1920 Load: 11.9 t ADT: 45

120 TH

Poor

Over: STREAM

085321501, Greene, IA

Built 1957 Load: 11.9 t ADT: 26

LOCAL

Poor

Over: SMALL STREAM

080112002, Iowa, IA

Built 1982 Load: 11.9 t ADT: 80

LOCAL

Poor

Over: JONES CREEK

075272906, Madison, IA

Built 1974 Load: 11.9 t ADT: 29

FM

Poor

Over: NORWAY CREEK

083423401, Monona, IA

Built 1953 Load: 11.9 t ADT: 40

FM

Poor

Over: CROOKED CK DD #60

092311602, Pocahontas, IA

Built 1973 Load: 11.9 t ADT: 40

LOCAL

Poor

Over: STREAM

088370602, Sac, IA

Built 1981 Load: 11.9 t ADT: 30

LOCAL

Poor

Over: W CEDAR CR.

088313001, Calhoun, IA

Built 1900 Load: 12.0 t ADT: 5

LOCAL

Poor

Over: EAST FORK BIG CREEK

067270103, Decatur, IA

Built 1967 Load: 12.0 t ADT: 113

F AVE.

Poor

Over: GUNDLACH CR

091073202, Fayette, IA

Built 1921 Load: 12.0 t ADT: 29

170TH ST

Poor

Over: COULEE

093091301, Fayette, IA

Built 1915 Load: 12.0 t ADT: 44

250TH ST

Poor

Over: UNNAMED CREEK

095103607, Fayette, IA

Built 1916 Load: 12.0 t ADT: 49

LOCAL

Poor

Over: CREEK

096163004, Floyd, IA

Built 1980 Load: 12.0 t ADT: 29

FM

Poor

Over: SMALL STREAM

078312704, Guthrie, IA

Built 1954 Load: 12.0 t ADT: 89

LOCAL

Poor

Over: STREAM

080320601, Guthrie, IA

Built 1951 Load: 12.0 t ADT: 11

S 88TH AVE W

Poor

Over: WALNUT CREEK

078210901, Jasper, IA

Built 1926 Load: 12.0 t ADT: 26

FM

Poor

Over: OTTER CREEK

073040302, Louisa, IA

Built 1955 Load: 12.0 t ADT: 35

150TH STREET

Poor

Over: WEST TARKIO RIVER

070383401, Page, IA

Built 1964 Load: 12.0 t ADT: 15

LOCAL

Poor

Over: W FK GRAND RIVER

068300303, Ringgold, IA

Built 1930 Load: 12.0 t ADT: 60

FM

Poor

Over: CREEK

096440701, Sioux, IA

Built 1949 Load: 12.0 t ADT: 20

LOCAL

Poor

Over: SMALL STREAM

072280806, Union, IA

Built 1940 Load: 12.0 t ADT: 26

LOCAL

Poor

Over: CAVITT CREEK

076240203, Warren, IA

Built 1967 Load: 12.0 t ADT: 176

LOCAL

Poor

Over: STREAM

090373102, Buena Vista, IA

Built 1975 Load: 12.1 t ADT: 20

LOCAL- 600TH ST

Poor

Over: MAPLE RIVER

090390501, Cherokee, IA

Built 1921 Load: 12.1 t ADT: 11

LOCAL

Poor

Over: WEST CREEK

073262104, Clarke, IA

Built 1949 Load: 12.1 t ADT: 26

Showing 17,851-17,900 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.