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

LOC B LEVEL RD

Poor

Over: STREAM

073311401, Union, IA

Built 1940 Load: 11.2 t ADT: 21

FM

Poor

Over: BR W PLATTE RIVER

073312502, Union, IA

Built 1957 Load: 11.2 t ADT: 788

LOCAL

Poor

Over: DAVIS CREEK

076071502, Washington, IA

Built 1980 Load: 11.2 t ADT: 11

FM

Poor

Over: MID FK MEDICINE RIVER

067221405, Wayne, IA

Built 1980 Load: 11.2 t ADT: 15

LOCAL

Poor

Over: BEAVER CREEK

083280901, Boone, IA

Built 1900 Load: 11.3 t ADT: 26

LOCAL - 700TH

Poor

Over: WATERWAY

075352302, Cass, IA

Built 1967 Load: 11.3 t ADT: 46

LOCAL

Poor

Over: W FK W NISHNABOTNA RIVER

082383302, Crawford, IA

Built 1944 Load: 11.3 t ADT: 46

FM

Poor

Over: SHANE CREEK

067272003, Decatur, IA

Built 1950 Load: 11.3 t ADT: 50

OTTER RD.

Poor

Over: CREEK

095093404, Fayette, IA

Built 1966 Load: 11.3 t ADT: 29

LOCAL

Poor

Over: BRUSH CREEK

085E30205, Jackson, IA

Built 1981 Load: 11.3 t ADT: 34

FM

Poor

Over: IOWA RIVER

085192707, Marshall, IA

Built 1952 Load: 11.3 t ADT: 49

LOCAL

Poor

Over: MINOR DRAINAGE

073391802, Montgomery, IA

Built 1966 Load: 11.3 t ADT: 5

EVERGREEN AVE

Poor

Over: DRAINAGE

091471902, Plymouth, IA

Built 1900 Load: 11.3 t ADT: 11

BUS US 30

Poor

Over: DEER CREEK

083152103, Tama, IA

Built 1953 Load: 11.3 t ADT: 2,887

FM

Poor

Over: TROUBLESOME CREEK

083131403, Tama, IA

Built 1964 Load: 11.3 t ADT: 226

LOCAL

Poor

Over: DUCK VALLEY

070212306, Wayne, IA

Built 1978 Load: 11.3 t ADT: 5

LOCAL

Poor

Over: OTTER CREEK

092262105, Wright, IA

Built 1967 Load: 11.3 t ADT: 31

FM

Poor

Over: CHARITON RIVER

068172607, Appanoose, IA

Built 1957 Load: 11.4 t ADT: 40

LOCAL

Poor

Over: STREAM

071272103, Clarke, IA

Built 1977 Load: 11.4 t ADT: 11

LOCAL

Poor

Over: BEAVER CREEK

078310204, Guthrie, IA

Built 1920 Load: 11.4 t ADT: 11

LOCAL

Poor

Over: HONEY BRANCH CREEK

072111904, Jefferson, IA

Built 1918 Load: 11.4 t ADT: 20

LOCAL

Poor

Over: S FORK ENGLISH RIVER

077122402, Keokuk, IA

Built 1953 Load: 11.4 t ADT: 34

LOCAL

Poor

Over: OTTER CR

073040103, Louisa, IA

Built 1921 Load: 11.4 t ADT: 16

FM

Poor

Over: GRAND RIVER

074292704, Madison, IA

Built 1957 Load: 11.4 t ADT: 131

LONE TREE RD

Poor

Over: PERRY CREEK

090472205, Plymouth, IA

Built 1953 Load: 11.4 t ADT: 71

120TH ST

Poor

Over: INDIAN CREEK

093471801, Plymouth, IA

Built 1900 Load: 11.4 t ADT: 15

LOCAL

Poor

Over: WILLOW CREEK

083411602, Crawford, IA

Built 1961 Load: 11.5 t ADT: 35

252 STREET

Poor

Over: DRAINAGE #10

068423003, Fremont, IA

Built 1920 Load: 11.5 t ADT: 5

FM

Poor

Over: SMALL STREAM

081110805, Iowa, IA

Built 1959 Load: 11.5 t ADT: 60

FM

Poor

Over: BIG BEAR CREEK

081162702, Poweshiek, IA

Built 1955 Load: 11.5 t ADT: 60

LOCAL B AVE.

Poor

Over: WEST FORK LITTLE SIOUX

091422902, Cherokee, IA

Built 1916 Load: 11.6 t ADT: 11

FM

Poor

Over: STREAM

069260704, Decatur, IA

Built 1952 Load: 11.6 t ADT: 29

LOCAL

Poor

Over: CREEK

097172602, Floyd, IA

Built 1956 Load: 11.6 t ADT: 26

LOCAL ROAD

Poor

Over: BRANCH BLACK HAWK CREEK

088152302, Grundy, IA

Built 1977 Load: 11.6 t ADT: 30

FM

Poor

Over: S RACCOON RIVER

079312302, Guthrie, IA

Built 1959 Load: 11.6 t ADT: 20

PINE AVE

Poor

Over: S BR TURKEY RIVER

098121502, Howard, IA

Built 1957 Load: 11.6 t ADT: 40

LOCAL ROAD

Poor

Over: LITTLE OTTER CREEK

098433502, Lyon, IA

Built 1900 Load: 11.6 t ADT: 26

LOCAL

Poor

Over: CEDAR CREEK

076141203, Mahaska, IA

Built 1973 Load: 11.6 t ADT: 26

LOCAL

Poor

Over: DRAINAGE

073161506, Monroe, IA

Built 1956 Load: 11.6 t ADT: 20

FM

Poor

Over: BUSHY CREEK

068352507, Taylor, IA

Built 1955 Load: 11.6 t ADT: 40

LOCAL

Poor

Over: LITTLE SOAP CREEK

071142002, Wapello, IA

Built 1930 Load: 11.6 t ADT: 30

LOCAL

Poor

Over: MIDDLE AVERY CREEK

072150603, Wapello, IA

Built 1972 Load: 11.6 t ADT: 73

FM

Poor

Over: COMSTOCK CREEK

073143001, Wapello, IA

Built 1991 Load: 11.6 t ADT: 40

LOCAL

Poor

Over: MIDDLE RIVER

076251410, Warren, IA

Built 1950 Load: 11.6 t ADT: 72

LOCAL

Poor

Over: STREAM

087420502, Woodbury, IA

Built 1940 Load: 11.6 t ADT: 15

270TH ST

Poor

Over: CREEK

079353101, Audubon, IA

Built 1959 Load: 11.7 t ADT: 20

LOCAL

Poor

Over: FIELD STREAM

084340404, Carroll, IA

Built 1913 Load: 11.7 t ADT: 26

LOCAL 580TH ST.

Poor

Over: ROCK CREEK

091412801, Cherokee, IA

Built 1917 Load: 11.7 t ADT: 5

LOCAL B AVE.

Poor

Over: FIDDLE CREEK

091421702, Cherokee, IA

Built 1915 Load: 11.7 t ADT: 20

LOCAL580TH ST

Poor

Over: FIDDLE CREEK

091423001, Cherokee, IA

Built 1917 Load: 11.7 t ADT: 5

Showing 17,801-17,850 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.