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

HOWARD AVE

Poor

Over: CRANE CREEK

098130504, Howard, IA

Built 1920 Load: 12.5 t ADT: 63

LOCAL

Poor

Over: DD

093293101, Humboldt, IA

Built 1900 Load: 12.5 t ADT: 11

FM

Poor

Over: OLIVE BRANCH CREEK

074140103, Mahaska, IA

Built 1950 Load: 12.5 t ADT: 30

LOCAL

Poor

Over: N LIZARD CREEK

093330701, Pocahontas, IA

Built 1916 Load: 12.5 t ADT: 5

FM

Poor

Over: WEST BRANCH 102 RIVER

070342201, Taylor, IA

Built 1936 Load: 12.5 t ADT: 309

LOCAL

Poor

Over: LITTLE SOAP CREEK

071133304, Wapello, IA

Built 1914 Load: 12.5 t ADT: 11

240TH STREET

Poor

Over: WEST FORK 102 RIVER

071341301, Adams, IA

Built 1974 Load: 12.6 t ADT: 34

4TH STREET

Poor

Over: STREAM

071340307, Adams, IA

Built 1925 Load: 12.6 t ADT: 120

FM

Poor

Over: BLUFF CREEK

085273101, Boone, IA

Built 1915 Load: 12.6 t ADT: 50

150TH ST

Poor

Over: BR ROCK CR

082033503, Cedar, IA

Built 1920 Load: 12.6 t ADT: 15

QUAIL

Poor

Over: BEAVER DAM CREEK

094203504, Cerro Gordo, IA

Built 1913 Load: 12.6 t ADT: 15

LOCAL

Poor

Over: ROCKY RUN

084383303, Crawford, IA

Built 1946 Load: 12.6 t ADT: 72

KENDALL TRAIL

Poor

Over: STEER CREEK

080441207, Harrison, IA

Built 1969 Load: 12.6 t ADT: 5

LOCAL

Poor

Over: BITTER CREEK

089411406, Ida, IA

Built 1960 Load: 12.6 t ADT: 30

LCL-380TH ST

Poor

Over: DEER CREEK

071400904, Mills, IA

Built 1977 Load: 12.6 t ADT: 5

FM

Poor

Over: STREAM

071181303, Monroe, IA

Built 1942 Load: 12.6 t ADT: 80

FM

Poor

Over: LITTLE TARKIO TRIB

071370701, Montgomery, IA

Built 1964 Load: 12.6 t ADT: 89

NOBLE AVE

Poor

Over: DEEP CREEK

093443104, Plymouth, IA

Built 1953 Load: 12.6 t ADT: 30

LOCAL ROAD

Poor

Over: MUD CREEK

078222706, Polk, IA

Built 1913 Load: 12.6 t ADT: 79

LOCAL

Poor

Over: SMALL STREAM

079382701, Shelby, IA

Built 1950 Load: 12.6 t ADT: 11

MISSOURI TAYLOR ST

Poor

Over: CREEK

067343403, Taylor, IA

Built 1900 Load: 12.6 t ADT: 5

FM

Poor

Over: WEST 102 RIVER

069353601, Taylor, IA

Built 1962 Load: 12.6 t ADT: 329

FM

Poor

Over: WEST FORK LITTLE SIOUX

087450302, Woodbury, IA

Built 1955 Load: 12.6 t ADT: 549

LOCAL-630TH ST

Poor

Over: N PIERSON CREEK

090422201, Cherokee, IA

Built 1920 Load: 12.7 t ADT: 20

LOCAL

Poor

Over: LITTLE TURKEY RIVER

096111402, Chickasaw, IA

Built 1966 Load: 12.7 t ADT: 62

LOCAL

Poor

Over: OTTER CREEK

073252503, Clarke, IA

Built 1980 Load: 12.7 t ADT: 11

250TH AVE

Poor

Over: STREAM

67251002, Decatur, IA

Built 1972 Load: 12.7 t ADT: 5

LOCAL

Poor

Over: LITTLE FLINT CREEK

071043502, Des Moines, IA

Built 1920 Load: 12.7 t ADT: 113

LOCAL

Poor

Over: CLEAR WATER CREEK

094183104, Floyd, IA

Built 1927 Load: 12.7 t ADT: 33

ROSEBUD AVE

Poor

Over: BUCK CREEK

078192902, Jasper, IA

Built 1919 Load: 12.7 t ADT: 104

LOCAL

Poor

Over: W. NISHNABOTNA

080381001, Shelby, IA

Built 1926 Load: 12.7 t ADT: 21

CHESTNUT AVENUE

Poor

Over: EAST NODAWAY RIVER

071351502, Adams, IA

Built 1930 Load: 12.8 t ADT: 26

LOCAL (LWC)

Poor

Over: BR PRAIRIE CK

082102004, Benton, IA

Built 1978 Load: 12.8 t ADT: 60

LOCAL

Poor

Over: BIG CEDAR RIVER

071092810, Jefferson, IA

Built 1991 Load: 12.8 t ADT: 34

LOCAL

Poor

Over: SNIPE CREEK

082193402, Marshall, IA

Built 1920 Load: 12.8 t ADT: 20

LOCAL

Poor

Over: BIG CEDAR CK DD #41

092343503, Pocahontas, IA

Built 1964 Load: 12.8 t ADT: 26

LOCAL

Poor

Over: STREAM

067291304, Ringgold, IA

Built 1953 Load: 12.8 t ADT: 5

LOCAL

Poor

Over: STREAM

071280205, Union, IA

Built 1991 Load: 12.8 t ADT: 35

LOCAL

Poor

Over: WHITE FOX CREEK

090252601, Wright, IA

Built 1975 Load: 12.8 t ADT: 21

LOCAL

Poor

Over: NODAWAY RIVER, BRANCH

074331202, Adair, IA

Built 1960 Load: 12.9 t ADT: 35

NOTCHWOOD AVE

Poor

Over: KEMP CREEK

073332804, Adams, IA

Built 1960 Load: 12.9 t ADT: 20

210TH ST

Poor

Over: BUCK CREEK

092113303, Bremer, IA

Built 1921 Load: 12.9 t ADT: 29

LOCAL

Poor

Over: PRAIRIE CREEK

086340201, Calhoun, IA

Built 1980 Load: 12.9 t ADT: 30

LOCAL

Poor

Over: MIDDLE RACOON RIVER

083342703, Carroll, IA

Built 1900 Load: 12.9 t ADT: 34

HENNEPIN RD

Poor

Over: ELK CREEK

091040208, Clayton, IA

Built 1920 Load: 12.9 t ADT: 25

280TH ST

Poor

Over: MOSQUITO CREEK

078410301, Harrison, IA

Built 1940 Load: 12.9 t ADT: 20

LOCAL RD

Poor

Over: TOM CREEK

077292502, Madison, IA

Built 1930 Load: 12.9 t ADT: 26

LOCAL

Poor

Over: STREAM

089370201, Sac, IA

Built 1924 Load: 12.9 t ADT: 30

FM 260TH ST

Poor

Over: QUARTER SEC RUN

091132005, Bremer, IA

Built 1939 Load: 13.0 t ADT: 275

FM

Poor

Over: CARTERS CREEK

068143506, Davis, IA

Built 1967 Load: 13.0 t ADT: 260

Showing 17,951-18,000 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.