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: NORTH SKUNK RIVER

082200203, Marshall, IA

Built 1938 Load: 22.0 t ADT: 29

LOCAL

Poor

Over: CREEK

084180609, Marshall, IA

Built 1955 Load: 22.0 t ADT: 148

SUNSET AVE

Poor

Over: DD

091431402, Plymouth, IA

Built 1956 Load: 22.0 t ADT: 20

FM

Poor

Over: BOYER RIVER

089370402, Sac, IA

Built 1956 Load: 22.0 t ADT: 848

FM

Poor

Over: SALT CREEK

084141103, Tama, IA

Built 1965 Load: 22.0 t ADT: 344

LOCAL

Poor

Over: STREAM

070101101, Van Buren, IA

Built 1930 Load: 22.0 t ADT: 21

FM

Poor

Over: SPRING CREEK

086112001, Benton, IA

Built 1959 Load: 22.1 t ADT: 430

FRANKLIN AVE

Poor

Over: BOYLAN CREEK

093192404, Franklin, IA

Built 1964 Load: 22.1 t ADT: 11

220TH STREET

Poor

Over: OTTER CREEK

093203001, Franklin, IA

Built 1972 Load: 22.1 t ADT: 21

FM

Poor

Over: CREEK

086243604, Hamilton, IA

Built 1957 Load: 22.1 t ADT: 240

1200 210TH ST

Poor

Over: WEST IOWA RIVER

095251201, Hancock, IA

Built 1961 Load: 22.1 t ADT: 170

FM 2380 DEER AV

Poor

Over: DRAINAGE DITCH 97

096262702, Hancock, IA

Built 1968 Load: 22.1 t ADT: 447

LOCAL

Poor

Over: CREEK

087200306, Hardin, IA

Built 1972 Load: 22.1 t ADT: 275

FM

Poor

Over: UNNAMED STREAM

089390102, Ida, IA

Built 1961 Load: 22.1 t ADT: 379

FM

Poor

Over: UNNAMED CREEK

089392310, Ida, IA

Built 1961 Load: 22.1 t ADT: 379

FM

Poor

Over: UNNAMED CREEK

0893925, Ida, IA

Built 1961 Load: 22.1 t ADT: 598

LOC 200TH ST

Poor

Over: PRAIRIE CREEK

095271501, Kossuth, IA

Built 1971 Load: 22.1 t ADT: 15

LOCAL

Poor

Over: WILLOW CREEK

082420103, Monona, IA

Built 1978 Load: 22.1 t ADT: 11

LOCAL

Poor

Over: STREAM

085432701, Monona, IA

Built 1900 Load: 22.1 t ADT: 60

L AVENUE

Poor

Over: SNAKE CREEK

069373106, Page, IA

Built 1979 Load: 22.1 t ADT: 60

240TH ST

Poor

Over: PERRY CREEK

091471401, Plymouth, IA

Built 1900 Load: 22.1 t ADT: 5

LOCAL

Poor

Over: SMALL STREAM

085160801, Tama, IA

Built 1986 Load: 22.1 t ADT: 39

LOCAL

Poor

Over: STREAM

086161803, Tama, IA

Built 1975 Load: 22.1 t ADT: 49

LOCAL (LWC)

Poor

Over: BRANCH ROCK CREEK

086123302, Benton, IA

Built 1984 Load: 22.2 t ADT: 5

LOCAL

Poor

Over: TRIB. OF FOX RIVER

069133504, Davis, IA

Built 1985 Load: 22.2 t ADT: 110

LOC 200TH ST

Poor

Over: LOTTS CREEK

095301701, Kossuth, IA

Built 1969 Load: 22.2 t ADT: 177

FM

Poor

Over: FIELD DRAINAGE DITCH

074261601, Madison, IA

Built 1951 Load: 22.2 t ADT: 417

FM

Poor

Over: BUSHY CREEK

067352603, Taylor, IA

Built 1952 Load: 22.2 t ADT: 40

FM

Poor

Over: NORTH BEAR CREEK

100072202, Winneshiek, IA

Built 1900 Load: 22.2 t ADT: 49

FM-110TH STREET

Poor

Over: WILLIAMS CREEK

073351001, Adams, IA

Built 1964 Load: 22.3 t ADT: 20

FM

Poor

Over: STREAM

080261101, Dallas, IA

Built 1970 Load: 22.3 t ADT: 1,544

FM

Poor

Over: SOUTH CHEQUEST LAKE CRK

069121302, Davis, IA

Built 1965 Load: 22.3 t ADT: 70

FM

Poor

Over: WHITE FOX CREEK

089252103, Hamilton, IA

Built 1960 Load: 22.3 t ADT: 330

FM

Poor

Over: CREEK

087203004, Hardin, IA

Built 1960 Load: 22.3 t ADT: 34

W 108TH ST S

Poor

Over: SMALL STREAM

079212502, Jasper, IA

Built 1947 Load: 22.3 t ADT: 41

LOCAL

Poor

Over: BYERS BRANCH CREEK

081213404, Jasper, IA

Built 1924 Load: 22.3 t ADT: 47

LOC 210TH AVE

Poor

Over: PRAIRIE CREEK

094273302, Kossuth, IA

Built 1979 Load: 22.3 t ADT: 81

LOC 110TH AVE

Poor

Over: E FORK DES MOINES RIVER

098292602, Kossuth, IA

Built 1980 Load: 22.3 t ADT: 30

LOCAL

Poor

Over: MIDDLE CREEK

076142910, Mahaska, IA

Built 1965 Load: 22.3 t ADT: 40

510TH STREET

Poor

Over: STREAM

077380304, Pottawattamie, IA

Built 1992 Load: 22.3 t ADT: 5

FM

Poor

Over: W FORK GRAND

070300303, Ringgold, IA

Built 1967 Load: 22.3 t ADT: 120

FM

Poor

Over: COTTON CREEK

074223202, Warren, IA

Built 1974 Load: 22.3 t ADT: 50

DOGWOOD

Poor

Over: DRAINAGE DITCH

099223402, Worth, IA

Built 1972 Load: 22.3 t ADT: 236

LOCAL

Poor

Over: STREAM

068182801, Appanoose, IA

Built 1948 Load: 22.4 t ADT: 30

LOCAL 260TH ST

Poor

Over: LIME CR

088102601, Buchanan, IA

Built 1986 Load: 22.4 t ADT: 41

LOCAL

Poor

Over: HONEY CREEK

087222202, Hardin, IA

Built 1980 Load: 22.4 t ADT: 21

LOCAL RD

Poor

Over: SMALL

075291205, Madison, IA

Built 1976 Load: 22.4 t ADT: 60

LOCAL

Poor

Over: DD 41

095332402, Palo Alto, IA

Built 1948 Load: 22.4 t ADT: 46

FM

Poor

Over: SILVER CREEK

078401103, Shelby, IA

Built 1960 Load: 22.4 t ADT: 131

E15/115TH ST

Poor

Over: LONG DICK CREEK

085230903, Story, IA

Built 1964 Load: 22.4 t ADT: 1,028

Showing 19,551-19,600 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.