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

470TH ST

Poor

Over: LITTLE SIOUX RIVER

094360906, Clay, IA

Built 1907 Load: 5.6 t ADT: 26

180TH ST

Poor

Over: BOHEMIAN CREEK

097110301, Howard, IA

Built 1953 Load: 5.6 t ADT: 42

215TH ST

Poor

Over: DES MOINES RIVER

092293403, Humboldt, IA

Built 1899 Load: 5.6 t ADT: 50

LOCAL RD

Poor

Over: DRAINAGE

075292305, Madison, IA

Built 1900 Load: 5.6 t ADT: 15

LOCAL

Poor

Over: SMALL STREAM

089361003, Sac, IA

Built 1980 Load: 5.6 t ADT: 15

LOCAL

Poor

Over: STREAM

068201103, Wayne, IA

Built 1900 Load: 5.6 t ADT: 5

LOCAL

Poor

Over: BLUFF CREEK

084270904, Boone, IA

Built 1900 Load: 5.7 t ADT: 20

LOCAL

Poor

Over: SMALL STREAM

091172202, Butler, IA

Built 1952 Load: 5.7 t ADT: 30

FM

Poor

Over: EAST SUGAR CREEK

080013001, Cedar, IA

Built 1914 Load: 5.7 t ADT: 20

325TH ST

Poor

Over: KEG CREEK

078412601, Harrison, IA

Built 1900 Load: 5.7 t ADT: 11

LOCAL

Poor

Over: SMALL RUNNING CREEK

098101003, Winneshiek, IA

Built 1900 Load: 5.7 t ADT: 29

FM

Poor

Over: S COAL CREEK

074171004, Mahaska, IA

Built 1951 Load: 5.8 t ADT: 10

LOCAL 270TH ST

Poor

Over: WAPSIPICON RVR OVERFLOW

091113301, Bremer, IA

Built 1965 Load: 5.9 t ADT: 11

LOCAL

Poor

Over: DRAINAGE DITCH

093381006, Buena Vista, IA

Built 1973 Load: 5.9 t ADT: 30

FM

Poor

Over: LITTLE BEAR CREEK

080122702, Iowa, IA

Built 1970 Load: 5.9 t ADT: 80

S 54TH AVE E

Poor

Over: ELK CREEK

079182103, Jasper, IA

Built 1976 Load: 5.9 t ADT: 48

LOCAL ROAD

Poor

Over: OVERFLOW

098433502, Lyon, IA

Built 1900 Load: 5.9 t ADT: 26

SIDE DITCH ENT

Poor

Over: SIDE DITCH

098471002, Lyon, IA

Built 1900 Load: 5.9 t ADT: 10

LOCAL RD

Poor

Over: BR TO MIDDLE

075290704, Madison, IA

Built 1942 Load: 5.9 t ADT: 50

FM

Poor

Over: LITTLE TARKIO TRIB

072373004, Montgomery, IA

Built 1947 Load: 5.9 t ADT: 29

PIONEER AVE

Poor

Over: DEEP CREEK

092440302, Plymouth, IA

Built 1917 Load: 5.9 t ADT: 30

IDELWOOD ROAD

Poor

Over: WALNUT CREEK

075380301, Pottawattamie, IA

Built 1977 Load: 5.9 t ADT: 11

LOCAL

Poor

Over: STREAM

068282701, Ringgold, IA

Built 1946 Load: 5.9 t ADT: 5

LOCAL

Poor

Over: CREEK

096093404, Winneshiek, IA

Built 1944 Load: 5.9 t ADT: 44

FM

Poor

Over: BRANCH LONG CREEK

071270504, Clarke, IA

Built 1952 Load: 6.0 t ADT: 15

LOCAL

Poor

Over: SMALL STREAM

071261705, Clarke, IA

Built 1900 Load: 6.0 t ADT: 11

R AVE.

Poor

Over: UNAMED CR

091091704, Fayette, IA

Built 1917 Load: 6.0 t ADT: 20

40TH ST

Poor

Over: OTTER CR

091091903, Fayette, IA

Built 1917 Load: 6.0 t ADT: 88

LCL-JARRED AVE

Poor

Over: CREEK

072402405, Mills, IA

Built 1940 Load: 6.0 t ADT: 15

LOCAL

Poor

Over: S. FORK LONG CREEK

076083602, Washington, IA

Built 1953 Load: 6.0 t ADT: 71

LOCAL

Poor

Over: LITTLE CEDAR

096151608, Floyd, IA

Built 1912 Load: 6.1 t ADT: 44

LOCAL

Poor

Over: NORTH ENGLISH RIVER

079113204, Iowa, IA

Built 1929 Load: 6.1 t ADT: 20

FM

Poor

Over: SMALL

079123003, Iowa, IA

Built 1952 Load: 6.1 t ADT: 45

LOCAL ROAD

Poor

Over: SMALL STREAM

098482304, Lyon, IA

Built 1900 Load: 6.1 t ADT: 21

LOCAL ROAD

Poor

Over: PAINTER CREEK

075252002, Warren, IA

Built 1958 Load: 6.1 t ADT: 35

MALLARD AVE

Poor

Over: BUFFALO CREEK

093203104, Franklin, IA

Built 1971 Load: 6.2 t ADT: 30

OLD BR.RD.

Poor

Over: PRAIRIE CREEK

082081204, Linn, IA

Built 1906 Load: 6.2 t ADT: 110

120TH ST

Poor

Over: W BR FLOYD RIVER

093451803, Plymouth, IA

Built 1941 Load: 6.2 t ADT: 20

LOCAL

Poor

Over: SO ENGLISH RIVER

078143401, Poweshiek, IA

Built 1980 Load: 6.2 t ADT: 50

LOCAL

Poor

Over: MIDDLE RIVER

077311701, Adair, IA

Built 1958 Load: 6.3 t ADT: 41

LOCAL

Poor

Over: NISHNABOTNA RIVER

079352203, Audubon, IA

Built 1958 Load: 6.3 t ADT: 35

207TH AVE

Poor

Over: STREAM

067262308, Decatur, IA

Built 1977 Load: 6.3 t ADT: 21

LOCAL

Poor

Over: SHAIN CREEK

067270401, Decatur, IA

Built 1991 Load: 6.3 t ADT: 35

LOCAL

Poor

Over: STREAM

081312802, Guthrie, IA

Built 1957 Load: 6.3 t ADT: 34

LOCAL

Poor

Over: TIPTON CREEK

087212502, Hardin, IA

Built 1989 Load: 6.3 t ADT: 35

RENO AVE

Poor

Over: SIX MILE CREEK

079421204, Harrison, IA

Built 1930 Load: 6.3 t ADT: 11

S 36TH AVE E

Poor

Over: SUGAR CREEK

079171203, Jasper, IA

Built 1979 Load: 6.3 t ADT: 21

LOC 110TH ST

Poor

Over: DRAINAGE DITCH 182

094283101, Kossuth, IA

Built 1951 Load: 6.3 t ADT: 41

ROSEDALE RD

Poor

Over: INDIAN CR

083062002, Linn, IA

Built 1890 Load: 6.3 t ADT: 299

LOCAL

Poor

Over: ENGLISH CREEK

073210101, Lucas, IA

Built 1979 Load: 6.3 t ADT: 11

Showing 17,301-17,350 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.