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: SOUTH LIZARD CREEK

089293105, Webster, IA

Built 1956 Load: 17.7 t ADT: 81

LOCAL

Poor

Over: DRAINAGE DITCH NO. 3

090303401, Webster, IA

Built 1913 Load: 17.7 t ADT: 30

LOCAL

Poor

Over: BRANCH MIDDLE RIVER

076311402, Adair, IA

Built 1900 Load: 17.8 t ADT: 21

LOCAL

Poor

Over: SHOAL CREEK

067171803, Appanoose, IA

Built 1900 Load: 17.8 t ADT: 11

LOCAL

Poor

Over: SQUAW CREEK

085252501, Boone, IA

Built 1900 Load: 17.8 t ADT: 15

PINE CREEK AVE

Poor

Over: SMALL STREAM

089081502, Buchanan, IA

Built 2012 Load: 17.8 t ADT: 30

LOCAL - 540TH

Poor

Over: LONE TREE BRANCH

074371902, Cass, IA

Built 1987 Load: 17.8 t ADT: 50

LOCAL - PELLA

Poor

Over: FOX CREEK

075362103, Cass, IA

Built 1987 Load: 17.8 t ADT: 21

LOCAL - 640TH

Poor

Over: LONE TREE BRANCH

076363504, Cass, IA

Built 1987 Load: 17.8 t ADT: 11

LOCAL

Poor

Over: EAST WAPSIPINICON RIVER

096132303, Chickasaw, IA

Built 1963 Load: 17.8 t ADT: 51

LOCAL

Poor

Over: BRUSH CREEK

071243602, Clarke, IA

Built 1981 Load: 17.8 t ADT: 20

LOCAL

Poor

Over: EAST LONG CREEK

071270103, Clarke, IA

Built 1900 Load: 17.8 t ADT: 5

LOCAL

Poor

Over: CARTERS CREEK

068151502, Davis, IA

Built 1958 Load: 17.8 t ADT: 5

IA 9

Poor

Over: W FORK LITTLE SIOUX RVR

4.9 mi. W of IA 86, Dickinson, IA

Built 1929 Load: 17.8 t ADT: 4,310

18TH ST.

Poor

Over: UNNAMED CREEK

091093405, Fayette, IA

Built 1962 Load: 17.8 t ADT: 69

LOCAL

Poor

Over: SEELEY CREEK

079320302, Guthrie, IA

Built 1968 Load: 17.8 t ADT: 199

FM

Poor

Over: BOONE RIVER

089251701, Hamilton, IA

Built 1955 Load: 17.8 t ADT: 60

FM

Poor

Over: SOUTH RIVER

074262604, Madison, IA

Built 1936 Load: 17.8 t ADT: 349

LOCAL

Poor

Over: SNIPE CREEK

082191502, Marshall, IA

Built 1950 Load: 17.8 t ADT: 16

LOCAL

Poor

Over: CREEK

083171003, Marshall, IA

Built 1953 Load: 17.8 t ADT: 104

LOCAL

Poor

Over: MINERVA CR

084201702, Marshall, IA

Built 1950 Load: 17.8 t ADT: 26

QUEST AVE

Poor

Over: RATHBURN CREEK

091431902, Plymouth, IA

Built 1950 Load: 17.8 t ADT: 26

FM

Poor

Over: NORTH SKUNK RIVER

078162704, Poweshiek, IA

Built 1958 Load: 17.8 t ADT: 70

LOCAL

Poor

Over: STREAM

069280101, Ringgold, IA

Built 1993 Load: 17.8 t ADT: 29

LOCAL RD

Poor

Over: STREAM

071293002, Union, IA

Built 1973 Load: 17.8 t ADT: 5

LOCAL

Poor

Over: STREAM

072291008, Union, IA

Built 1985 Load: 17.8 t ADT: 180

FM

Poor

Over: SKUNK RIVER

074091004, Washington, IA

Built 1957 Load: 17.8 t ADT: 120

FM

Poor

Over: COOPER CREEK

068180702, Appanoose, IA

Built 1948 Load: 17.9 t ADT: 120

LOCAL

Poor

Over: KIRKENDALL CREEK

068192704, Appanoose, IA

Built 1950 Load: 17.9 t ADT: 73

LOCAL - UPLAND

Poor

Over: WHISTLERS BRANCH

074351601, Cass, IA

Built 1983 Load: 17.9 t ADT: 5

LOCAL-U AVE

Poor

Over: OVERFLOW CHANNEL

090390902, Cherokee, IA

Built 1925 Load: 17.9 t ADT: 15

LOCAL 570TH ST.

Poor

Over: PERRY CREEK

091401901, Cherokee, IA

Built 1948 Load: 17.9 t ADT: 11

LOCAL

Poor

Over: SMALL STREAM

080301903, Guthrie, IA

Built 1982 Load: 17.9 t ADT: 29

LOCAL

Poor

Over: BREWERS CR

088260304, Hamilton, IA

Built 1926 Load: 17.9 t ADT: 15

LOCAL

Poor

Over: BUCKLEY CREEK

077170503, Mahaska, IA

Built 1929 Load: 17.9 t ADT: 131

LOCAL

Poor

Over: SOUTH TIMBER CREEK

083173201, Marshall, IA

Built 1949 Load: 17.9 t ADT: 34

LOCAL

Poor

Over: BEAVER CREEK

084283301, Boone, IA

Built 1920 Load: 18.0 t ADT: 20

LOCAL

Poor

Over: BROOKS CREEK

092381101, Buena Vista, IA

Built 1924 Load: 18.0 t ADT: 11

FM

Poor

Over: CROOKED CREEK

079020803, Cedar, IA

Built 1923 Load: 18.0 t ADT: 230

FM

Poor

Over: ROCK CREEK

080031603, Cedar, IA

Built 1967 Load: 18.0 t ADT: 1,660

FM 590TH ST.

Poor

Over: ROCK CREEK

091413301, Cherokee, IA

Built 1970 Load: 18.0 t ADT: 45

FM

Poor

Over: LITTLE CEDAR

095142103, Chickasaw, IA

Built 1964 Load: 18.0 t ADT: 579

LOCAL

Poor

Over: SMALL

097122702, Chickasaw, IA

Built 1979 Load: 18.0 t ADT: 91

FM

Poor

Over: TRIBUTARY TO FOX RIVER

069152403, Davis, IA

Built 1970 Load: 18.0 t ADT: 50

FM

Poor

Over: WELDON RIVER

070240903, Decatur, IA

Built 1973 Load: 18.0 t ADT: 26

LOCAL

Poor

Over: DD #40

100323302, Emmet, IA

Built 1968 Load: 18.0 t ADT: 11

2740 URBAN AVE

Poor

Over: DD #13

096230404, Hancock, IA

Built 1969 Load: 18.0 t ADT: 15

FM

Poor

Over: TIPTON CREEK

088223201, Hardin, IA

Built 1900 Load: 18.0 t ADT: 334

198TH ST

Poor

Over: SMALL CREEK

080422211, Harrison, IA

Built 1950 Load: 18.0 t ADT: 79

LOCAL

Poor

Over: STREAM

087410202, Ida, IA

Built 1900 Load: 18.0 t ADT: 21

Showing 18,901-18,950 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.