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: BRANCH TO CLANTON CREEK

074270104, Madison, IA

Built 1940 Load: 3.0 t ADT: 71

35TH AVE

Poor

Over: CREEK

080E13406, Scott, IA

Built 1965 Load: 3.0 t ADT: 25

FM

Poor

Over: STREAM

068271302, Decatur, IA

Built 1957 Load: 3.1 t ADT: 60

LOCAL

Poor

Over: BR.BURR OAK CREEK

073080907, Jefferson, IA

Built 1962 Load: 3.1 t ADT: 40

110TH STREET

Poor

Over: STREAM

070381101, Page, IA

Built 1953 Load: 3.1 t ADT: 20

LOCAL

Poor

Over: CREEK

068332504, Taylor, IA

Built 1952 Load: 3.1 t ADT: 5

LOCAL

Poor

Over: EAST PLATTE RIVER

071300905, Union, IA

Built 1969 Load: 3.1 t ADT: 15

LOCAL - 570TH

Poor

Over: WATERWAY

074371002, Cass, IA

Built 1955 Load: 3.2 t ADT: 30

Ag and DNR Traffic

Poor

Over: Prairie Creek

Marion Co., S20,T77N,R20, Marion, IA

Built 1952 Load: 3.2 t ADT: 1

LOCAL RD

Poor

Over: WEST NODAWAY RIVER

072362803, Montgomery, IA

Built 1940 Load: 3.2 t ADT: 45

632ND AVE

Poor

Over: WEST BR INDIAN CREEK

082220806, Story, IA

Built 1938 Load: 3.2 t ADT: 60

FM

Poor

Over: LITTLE BEAVER CREEK

082273302, Boone, IA

Built 1973 Load: 3.3 t ADT: 45

LOCAL

Poor

Over: MAYNES CREEK

091171802, Butler, IA

Built 1900 Load: 3.3 t ADT: 26

FM

Poor

Over: WEST CREEK

073262704, Clarke, IA

Built 1965 Load: 3.3 t ADT: 29

LOCAL

Poor

Over: WELDON RIVER

070243301, Decatur, IA

Built 1962 Load: 3.3 t ADT: 30

LOCAL

Poor

Over: STREAM

080301005, Guthrie, IA

Built 1941 Load: 3.3 t ADT: 15

LOCAL

Poor

Over: BEAVER CREEK

087200203, Hardin, IA

Built 1985 Load: 3.3 t ADT: 29

LOCAL

Poor

Over: MIDDLE TIMBER CREEK

083182604, Marshall, IA

Built 1916 Load: 3.3 t ADT: 51

LOCAL

Poor

Over: WALNUT CR

069203404, Wayne, IA

Built 1973 Load: 3.3 t ADT: 50

LOCAL

Poor

Over: EAGLE CREEK

092252901, Wright, IA

Built 1975 Load: 3.3 t ADT: 11

FM - JACKSON

Poor

Over: WATERWAY

076361406, Cass, IA

Built 1985 Load: 3.4 t ADT: 139

LOCAL 90TH ST

Poor

Over: CRANE CREEK

099132003, Howard, IA

Built 1951 Load: 3.4 t ADT: 21

LOCAL

Poor

Over: TRIB S FK ENGLISH RIVER

077110304, Keokuk, IA

Built 1972 Load: 3.4 t ADT: 11

FM 90TH AVE

Poor

Over: FOUR MILE CREEK

095292802, Kossuth, IA

Built 1965 Load: 3.4 t ADT: 638

LOCAL ROAD

Poor

Over: BLOOD RUN CREEK

100482302, Lyon, IA

Built 1900 Load: 3.4 t ADT: 90

LOCAL

Poor

Over: DEEP RIVER

078130102, Poweshiek, IA

Built 1983 Load: 3.4 t ADT: 20

FM

Poor

Over: RICHLAND CREEK

082151902, Tama, IA

Built 1935 Load: 3.4 t ADT: 39

LOCAL

Poor

Over: CREEK

068082606, Van Buren, IA

Built 1960 Load: 3.4 t ADT: 21

LOCAL

Poor

Over: PIKE RUN

099241701, Winnebago, IA

Built 1976 Load: 3.4 t ADT: 11

LOCAL

Poor

Over: FARMERS DITCH

086461204, Woodbury, IA

Built 1980 Load: 3.4 t ADT: 11

LOCAL

Poor

Over: STREAM

089433101, Woodbury, IA

Built 1955 Load: 3.4 t ADT: 11

LOCAL

Poor

Over: BR CARRUTHERS CREEK

073200304, Lucas, IA

Built 1957 Load: 3.5 t ADT: 82

LOCAL

Poor

Over: DRAINAGE

076291906, Madison, IA

Built 1965 Load: 3.5 t ADT: 11

LOCAL

Poor

Over: BEAVER CREEK

082280304, Boone, IA

Built 1915 Load: 3.6 t ADT: 20

FM

Poor

Over: DM RIVER

092302305, Humboldt, IA

Built 1905 Load: 3.6 t ADT: 30

LOCAL

Poor

Over: BR OF CEDAR CREEK

071200207, Lucas, IA

Built 1940 Load: 3.6 t ADT: 11

100TH ST

Poor

Over: KEIGLEY BRANCH

085240501, Story, IA

Built 1900 Load: 3.6 t ADT: 15

LOCAL

Poor

Over: W 102 RIVER

069351605, Taylor, IA

Built 1963 Load: 3.6 t ADT: 5

FM

Poor

Over: S RIVER

075251304, Warren, IA

Built 1940 Load: 3.6 t ADT: 71

LOCAL - SEATTLE

Poor

Over: WATERWAY

074370605, Cass, IA

Built 1978 Load: 3.7 t ADT: 35

FM

Poor

Over: SOLDIER RIVER

085412002, Crawford, IA

Built 1957 Load: 3.7 t ADT: 40

FOX RD.

Poor

Over: VOLGA RIVER

093073003, Fayette, IA

Built 1905 Load: 3.7 t ADT: 15

FM

Poor

Over: BR IOWA RIVER

083151103, Tama, IA

Built 1995 Load: 3.7 t ADT: 717

FIELD ENTRANCE

Poor

Over: TRIB DES MOINES RIVER

084272305, Boone, IA

Built 1900 Load: 3.8 t ADT: 40

FM

Poor

Over: LITTLE WAPSIPINICON RVR

096130701, Chickasaw, IA

Built 1961 Load: 3.8 t ADT: 265

LOCAL RD

Poor

Over: BLACK HAWK CREEK

088161602, Grundy, IA

Built 1971 Load: 3.8 t ADT: 11

LOCAL

Poor

Over: BR OF BRUSH CREEK

072232003, Lucas, IA

Built 1953 Load: 3.8 t ADT: 41

FIELD ENTRANCE

Poor

Over: STREAM (SDB)

068363602, Page, IA

Built 1979 Load: 3.8 t ADT: 10

FIELD ENTRANCE

Poor

Over: SIDE DRAINAGE (SDB)

068083104, Van Buren, IA

Built 1976 Load: 3.8 t ADT: 10

MASON AVE

Poor

Over: STREAM

089420804, Woodbury, IA

Built 1970 Load: 3.8 t ADT: 5

Showing 17,151-17,200 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.