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

FM

Poor

Over: DOWD CREEK, BRANCH

086182101, Grundy, IA

Built 1966 Load: 16.4 t ADT: 187

LOCAL

Poor

Over: SNIPE CREEK

081190401, Jasper, IA

Built 1921 Load: 16.4 t ADT: 51

LOCAL

Poor

Over: COAL CREEK

076133601, Keokuk, IA

Built 1948 Load: 16.4 t ADT: 15

FM

Poor

Over: SO SKUNK RIVER

075151108, Mahaska, IA

Built 1956 Load: 16.4 t ADT: 290

LOCAL

Poor

Over: LUTES CREEK

082170702, Marshall, IA

Built 1937 Load: 16.4 t ADT: 82

FM

Poor

Over: NAGEL DD

084440804, Monona, IA

Built 1960 Load: 16.4 t ADT: 79

LOCAL

Poor

Over: WALNUT CREEK

081141702, Poweshiek, IA

Built 1915 Load: 16.4 t ADT: 26

LOCAL

Poor

Over: SMALL STREAM

086362601, Sac, IA

Built 1974 Load: 16.4 t ADT: 15

107TH AVE

Poor

Over: CREEK

096071306, Winneshiek, IA

Built 1965 Load: 16.4 t ADT: 78

LOCAL

Poor

Over: CREEK

080361902, Audubon, IA

Built 1926 Load: 16.5 t ADT: 11

LOCAL

Poor

Over: MORGAN CREEK

083093602, Benton, IA

Built 1964 Load: 16.5 t ADT: 90

FM

Poor

Over: SMALL STREAM

085100602, Benton, IA

Built 1925 Load: 16.5 t ADT: 940

FM

Poor

Over: BRUSH CREEK

069252401, Decatur, IA

Built 1980 Load: 16.5 t ADT: 60

LOCAL

Poor

Over: ALLOWAY CREEK

081181601, Jasper, IA

Built 1974 Load: 16.5 t ADT: 11

MATSELL PK RD

Poor

Over: WAPSIPINICON RIVER

085053606, Linn, IA

Built 1939 Load: 16.5 t ADT: 147

WALNUT AVE

Poor

Over: WAPSIPINICON RIVER

099151402, Mitchell, IA

Built 1940 Load: 16.5 t ADT: 462

LOCAL

Poor

Over: OTTER CREEK

099421102, Osceola, IA

Built 1949 Load: 16.5 t ADT: 5

LOCAL ROAD

Poor

Over: SMALL STREAM

086382201, Sac, IA

Built 1932 Load: 16.5 t ADT: 30

FIELD ENTRANCE

Poor

Over: SIDE DITCH

067320102, Taylor, IA

Built 1980 Load: 16.5 t ADT: 10

LOCAL

Poor

Over: PLATTE RIVER

071312602, Union, IA

Built 1989 Load: 16.5 t ADT: 11

EMMETT AVE

Poor

Over: DEER CREEK

088462304, Woodbury, IA

Built 1977 Load: 16.5 t ADT: 45

LOCAL

Poor

Over: DRAINAGE DITCH 36

091250302, Wright, IA

Built 1980 Load: 16.5 t ADT: 30

LOCAL

Poor

Over: CREEK

079362501, Audubon, IA

Built 1940 Load: 16.6 t ADT: 5

LOCAL

Poor

Over: BR OPOSSUM CK

084090601, Benton, IA

Built 1958 Load: 16.6 t ADT: 20

160TH ST

Poor

Over: QUARTER SECTION RUN CR

092130401, Bremer, IA

Built 1992 Load: 16.6 t ADT: 49

242TH ST.

Poor

Over: UNAMED CREEK

094090607, Fayette, IA

Built 1973 Load: 16.6 t ADT: 148

LOCAL

Poor

Over: CREEK

097172601, Floyd, IA

Built 1956 Load: 16.6 t ADT: 78

210TH STREET

Poor

Over: DRAINAGE

069433403, Fremont, IA

Built 1966 Load: 16.6 t ADT: 15

FM

Poor

Over: BLACKHAWK CREEK ,BRANCH

088162001, Grundy, IA

Built 1956 Load: 16.6 t ADT: 177

LOCAL

Poor

Over: DRAINAGE

077263103, Madison, IA

Built 1972 Load: 16.6 t ADT: 50

LOCAL

Poor

Over: BR MINERVA CREEK

085201802, Marshall, IA

Built 1941 Load: 16.6 t ADT: 40

FM

Poor

Over: GREYS CREEK

073172208, Monroe, IA

Built 1965 Load: 16.6 t ADT: 60

LOCAL

Poor

Over: BRANCH IOWA RIVER

081140201, Poweshiek, IA

Built 1988 Load: 16.6 t ADT: 60

LOCAL

Poor

Over: FORK NORTH CHARITON

070230402, Wayne, IA

Built 1988 Load: 16.6 t ADT: 20

LOCAL

Poor

Over: MIDDLE RIVER

077320101, Adair, IA

Built 1915 Load: 16.7 t ADT: 29

180TH ST

Poor

Over: SUGAR CREEK

081021603, Cedar, IA

Built 1976 Load: 16.7 t ADT: 45

U AVE

Poor

Over: MAPLE CREEK

091390401, Cherokee, IA

Built 1976 Load: 16.7 t ADT: 5

LOCAL G AVE

Poor

Over: FOUR MILE CREEK

093411802, Cherokee, IA

Built 1976 Load: 16.7 t ADT: 20

LOCAL

Poor

Over: SOUTH RIVER

073271404, Clarke, IA

Built 1900 Load: 16.7 t ADT: 40

FM

Poor

Over: FOX RIVER

069152702, Davis, IA

Built 1955 Load: 16.7 t ADT: 50

LOCAL

Poor

Over: W. FORK BIG CREEK

068273101, Decatur, IA

Built 1970 Load: 16.7 t ADT: 15

LOCAL ROAD

Poor

Over: WOLF CREEK

086180202, Grundy, IA

Built 1970 Load: 16.7 t ADT: 11

LOCAL

Poor

Over: BR BEAVER CREEK

089172802, Grundy, IA

Built 1979 Load: 16.7 t ADT: 15

E 28TH ST S

Poor

Over: SMALL STREAM

079192402, Jasper, IA

Built 1967 Load: 16.7 t ADT: 51

LOC 490TH ST

Poor

Over: W BR BLUE EARTH RIVER

100282101, Kossuth, IA

Built 1980 Load: 16.7 t ADT: 5

LOCAL

Poor

Over: BRANCH SKUNK RIVER

077180403, Marion, IA

Built 1970 Load: 16.7 t ADT: 62

LANCER AVE

Poor

Over: SMALL NATURAL STREAM

099172406, Mitchell, IA

Built 1925 Load: 16.7 t ADT: 1,011

LOCAL

Poor

Over: DRAINAGE

073371904, Montgomery, IA

Built 1987 Load: 16.7 t ADT: 5

FM

Poor

Over: MUD CREEK

078010302, Muscatine, IA

Built 1939 Load: 16.7 t ADT: 50

240TH ST

Poor

Over: BIG WHISKEY SLOUGH

091431401, Plymouth, IA

Built 1953 Load: 16.7 t ADT: 11

Showing 18,601-18,650 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.