State profile · Above national median SD

Iowa bridge safety

Condition ratings, load ratings, and structural-deficiency data for every public highway bridge in Iowa — drawn straight from the FHWA National Bridge Inventory.

20,753
Public bridges
36.5%
Good condition
20.0%
Poor condition
20.0%
Structurally deficient

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 rated 0-4

Structurally Deficient

20.0%

4,153 bridges flagged for repair priority

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 — Structurally deficient share 66.7%
National avg

Lower is better. Bar maxes at 30% (worst-state ceiling). National average sits at 7.0%.

Condition Distribution

Bridge inventory deck-condition mix — Iowa (FHWA NBI)

Iowa36.534476943092564%38.39444899532597%20.011564593070883%20.011564593070883%GoodFairPoorStructurally Deficient
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 on the structurally deficient leaderboard (lower share = better)

States are ranked by share of bridges flagged structurally deficient — the FHWA classification for any span where deck, superstructure, or substructure carries a condition rating of 4 or below. Lower percentages indicate stronger maintenance funding and inspection follow-through. States here sit immediately above and below Iowa on the same metric.

54

West Virginia

16.02% top marginal rate
Structure
Progressive
Burden @ $100K
$7,679

46

South Dakota

16.24% top marginal rate
Structure
Progressive
Burden @ $100K
$5,905
Selected

19

Iowa

20.01% top marginal rate
Structure
Progressive
Burden @ $100K
$20,753

78

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 composite NBI rating. Each is inspected at least every 24 months.

270TH STREET

Structurally Deficient

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

Structurally Deficient

Over: MUD CREEK

87-12-15-02-10, Black Hawk, IA

Built 1948 Load: 2.7 t ADT: 11

LOCAL - 700TH

Structurally Deficient

Over: TRIB TROUBLESOME CREEK

077351402, Cass, IA

Built 1983 Load: 2.7 t ADT: 11

LOCAL - DAYTONA

Structurally Deficient

Over: BUCK CREEK

077361903, Cass, IA

Built 1980 Load: 2.7 t ADT: 35

100TH ST.

Structurally Deficient

Over: UNION CREEK

083E20101, Clinton, IA

Built 1900 Load: 2.7 t ADT: 78

All Bridges in Iowa

OLD IA HWY 25

Structurally Deficient

Over: SMALL STREAM

068313004, Ringgold, IA

Built 1934 Load: 17.1 t ADT: 289

FM

Structurally Deficient

Over: TRAIL

070303203, Ringgold, IA

Built 1940 Load: 17.1 t ADT: 190

275TH STREET

Structurally Deficient

Over: LONG BRANCH

071353404, Adams, IA

Built 1958 Load: 17.2 t ADT: 11

120TH STREET

Structurally Deficient

Over: STREAM

073321701, Adams, IA

Built 1973 Load: 17.2 t ADT: 11

140TH STREET

Structurally Deficient

Over: EAST NODAWAY RIVER

073322801, Adams, IA

Built 1900 Load: 17.2 t ADT: 11

GROVE AVENUE

Structurally Deficient

Over: WILLIAMS CREEK

073340502, Adams, IA

Built 1970 Load: 17.2 t ADT: 5

LOCAL

Structurally Deficient

Over: CREEK

072113302, Jefferson, IA

Built 1900 Load: 17.2 t ADT: 110

LOCAL

Structurally Deficient

Over: SPRING CREEK

075151703, Mahaska, IA

Built 1964 Load: 17.2 t ADT: 90

LOCAL

Structurally Deficient

Over: BRUSH CREEK

082171603, Marshall, IA

Built 1917 Load: 17.2 t ADT: 16

FM

Structurally Deficient

Over: LINN CR

083180902, Marshall, IA

Built 1956 Load: 17.2 t ADT: 369

FM

Structurally Deficient

Over: W FORK GRAND RIVER

067311501, Ringgold, IA

Built 1956 Load: 17.2 t ADT: 219

FM

Structurally Deficient

Over: ROCK CREEK

088430603, Woodbury, IA

Built 1900 Load: 17.2 t ADT: 199

FM

Structurally Deficient

Over: DRAINAGE

074271004, Madison, IA

Built 1940 Load: 17.3 t ADT: 89

190TH STREET

Structurally Deficient

Over: MIDDLE TARKIO CREEK

069382303, Page, IA

Built 1956 Load: 17.3 t ADT: 139

FM

Structurally Deficient

Over: CAMP CREEK

079222604, Polk, IA

Built 1950 Load: 17.3 t ADT: 459

LOCAL 90TH ST

Structurally Deficient

Over: BR CRANE CREEK

099132101, Howard, IA

Built 1970 Load: 17.4 t ADT: 16

LOCAL

Structurally Deficient

Over: BRANCH N SKUNK RIVER

082191902, Marshall, IA

Built 1954 Load: 17.4 t ADT: 15

LOCAL

Structurally Deficient

Over: SMALL STREAM

090180702, Butler, IA

Built 1965 Load: 17.5 t ADT: 41

160TH ST

Structurally Deficient

Over: STREAM

092150301, Butler, IA

Built 1990 Load: 17.5 t ADT: 41

LOCAL ROAD

Structurally Deficient

Over: WEST BRANCH IOWA RIVER

093241106, Wright, IA

Built 1919 Load: 17.5 t ADT: 11

LOCAL - 700TH

Structurally Deficient

Over: TURKEY CREEK

076350204, Cass, IA

Built 1978 Load: 17.6 t ADT: 21

S12TH AVE E

Structurally Deficient

Over: SMALL STREAM

079180501, Jasper, IA

Built 1921 Load: 17.6 t ADT: 104

LOCAL

Structurally Deficient

Over: COLDWATER CREEK

093180505, Butler, IA

Built 1951 Load: 17.7 t ADT: 11

LOCAL

Structurally Deficient

Over: SMALL CREEK

072251103, Clarke, IA

Built 1900 Load: 17.7 t ADT: 40

LOCAL

Structurally Deficient

Over: SOUTH LIZARD CREEK

089293105, Webster, IA

Built 1956 Load: 17.7 t ADT: 81

LOCAL

Structurally Deficient

Over: BRANCH MIDDLE RIVER

076311402, Adair, IA

Built 1900 Load: 17.8 t ADT: 21

LOCAL

Structurally Deficient

Over: SHOAL CREEK

067171803, Appanoose, IA

Built 1900 Load: 17.8 t ADT: 11

LOCAL

Structurally Deficient

Over: BRUSH CREEK

071243602, Clarke, IA

Built 1981 Load: 17.8 t ADT: 20

FM

Structurally Deficient

Over: SOUTH RIVER

074262604, Madison, IA

Built 1936 Load: 17.8 t ADT: 349

FM

Structurally Deficient

Over: TIPTON CREEK

088223201, Hardin, IA

Built 1900 Load: 18.0 t ADT: 334

LOCAL

Structurally Deficient

Over: STREAM

087410202, Ida, IA

Built 1900 Load: 18.0 t ADT: 21

100TH AVE

Structurally Deficient

Over: MOUSE CREEK

073233002, Lucas, IA

Built 1975 Load: 18.0 t ADT: 11

FM

Structurally Deficient

Over: HOWERDON CREEK

076283002, Madison, IA

Built 1954 Load: 18.0 t ADT: 477

FM

Structurally Deficient

Over: W FORK GRAND RIVER

070302101, Ringgold, IA

Built 1950 Load: 18.0 t ADT: 60

FM

Structurally Deficient

Over: BOYER RIVER

086372806, Sac, IA

Built 1958 Load: 18.0 t ADT: 60

LOCAL

Structurally Deficient

Over: TRIB OF DES MOINES RIVER

068083508, Van Buren, IA

Built 1954 Load: 18.0 t ADT: 62

KILLDEER

Structurally Deficient

Over: BEAVER DAM CREEK

095212602, Cerro Gordo, IA

Built 1900 Load: 18.1 t ADT: 16

FM

Structurally Deficient

Over: SEVEN MILE CREEK

067272401, Decatur, IA

Built 1957 Load: 18.1 t ADT: 131

270 STREET

Structurally Deficient

Over: MILL CREEK

067400401, Fremont, IA

Built 1959 Load: 18.1 t ADT: 26

VAIL AVE

Structurally Deficient

Over: OVER CC RR

089232704, Hamilton, IA

Built 1932 Load: 18.1 t ADT: 578

LOCAL RD

Structurally Deficient

Over: DRAINAGE

077280103, Madison, IA

Built 1956 Load: 18.1 t ADT: 60

140TH ST

Structurally Deficient

Over: MINERVA CREEK

085202703, Marshall, IA

Built 1912 Load: 18.1 t ADT: 62

BIG ROCK RD

Structurally Deficient

Over: CREEK

080E10304, Scott, IA

Built 1923 Load: 18.1 t ADT: 1,060

LOCAL

Structurally Deficient

Over: DRAINAGE DITCH 7

090230203, Wright, IA

Built 1963 Load: 18.1 t ADT: 73

160TH ST

Structurally Deficient

Over: BASKINS CREEK

092130601, Bremer, IA

Built 1961 Load: 18.2 t ADT: 33

FM

Structurally Deficient

Over: WATERWAY

075281203, Madison, IA

Built 1930 Load: 18.2 t ADT: 100

FM

Structurally Deficient

Over: STREAM

080132305, Poweshiek, IA

Built 1924 Load: 18.2 t ADT: 750

ROYAL ST

Structurally Deficient

Over: BUCK CREEK

078192104, Jasper, IA

Built 1925 Load: 18.3 t ADT: 41

LOCAL

Structurally Deficient

Over: TRIB.DES MOINES RIVER

084272203, Boone, IA

Built 1900 Load: 18.4 t ADT: 71

FM

Structurally Deficient

Over: BATTLE CREEK

075310102, Adair, IA

Built 1959 Load: 18.5 t ADT: 50

Showing 20,501-20,550 of 20,753 bridges

Related

All states → | National rankings → | Understanding conditions → | SD bridges explained →
Data sourced from the FHWA National Bridge Inventory (NBI), latest released cycle. See our methodology for details. Retrieved and formatted by PlainBridges Editorial.

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). A "structurally deficient" rating is a repair-priority signal, not a closure or unsafe-to-cross designation. Consult a qualified civil engineer before making decisions based on this data.

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.