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

FM

Poor

Over: CREEK

086E53004, Jackson, IA

Built 1977 Load: 36.6 t ADT: 120

WAUBEEK RD

Poor

Over: TRIB WAPSIPINICON R

085061403, Linn, IA

Built 1927 Load: 36.6 t ADT: 78

VINE

Poor

Over: DEER CREEK

100192702, Worth, IA

Built 1977 Load: 36.6 t ADT: 59

MALLARD AVE

Poor

Over: DRAINAGE DITCH

100203102, Worth, IA

Built 1973 Load: 36.6 t ADT: 216

FM

Poor

Over: WAPSIPINICON RIVER

082011408, Cedar, IA

Built 1969 Load: 36.7 t ADT: 520

LOCAL

Poor

Over: SMALL STREAM

087433503, Woodbury, IA

Built 1985 Load: 36.8 t ADT: 11

FM

Poor

Over: PRATT CREEK

086112502, Benton, IA

Built 1989 Load: 36.9 t ADT: 540

170TH AVE

Poor

Over: SAND CREEK

088050802, Delaware, IA

Built 1953 Load: 36.9 t ADT: 39

FM

Poor

Over: BLOOD RUN CREEK

100481902, Lyon, IA

Built 1971 Load: 36.9 t ADT: 180

KILLDEER

Poor

Over: ELK CREEK

099212302, Worth, IA

Built 2001 Load: 36.9 t ADT: 137

FM

Poor

Over: BEAVER CREEK ,BRANCH

088181705, Grundy, IA

Built 1932 Load: 37.1 t ADT: 265

FM

Poor

Over: COMPETINE CREEK

076193306, Marion, IA

Built 1967 Load: 37.1 t ADT: 710

LOCAL

Poor

Over: STREAM

077191002, Marion, IA

Built 1967 Load: 37.1 t ADT: 41

FM-210TH STREET

Poor

Over: KEMP CREEK

072343103, Adams, IA

Built 1988 Load: 37.2 t ADT: 180

FM

Poor

Over: PATTERSON CREEK

099062905, Allamakee, IA

Built 1938 Load: 37.2 t ADT: 69

LOCAL

Poor

Over: CLEAR CREEK

100051404, Allamakee, IA

Built 1915 Load: 37.2 t ADT: 5

LOCAL ROAD

Poor

Over: CREEK

098082406, Winneshiek, IA

Built 1971 Load: 37.2 t ADT: 11

190TH ST

Poor

Over: QUARTER SECTION RUN

092132301, Bremer, IA

Built 1948 Load: 37.4 t ADT: 1,188

LOCAL

Poor

Over: SMALL STREAM

094112401, Chickasaw, IA

Built 1985 Load: 37.4 t ADT: 29

FM

Poor

Over: LINN CREEK

083200304, Marshall, IA

Built 1988 Load: 37.4 t ADT: 737

LOCAL

Poor

Over: BR N LIZARD CR DD#169

091310602, Pocahontas, IA

Built 1989 Load: 37.5 t ADT: 5

FM

Poor

Over: DOWD CREEK

086183004, Grundy, IA

Built 1972 Load: 37.6 t ADT: 491

LOCAL

Poor

Over: INDIAN CREEK

075041301, Louisa, IA

Built 1969 Load: 37.7 t ADT: 62

AVE L

Poor

Over: DRY CREEK

076040507, Lee, IA

Built 1915 Load: 37.9 t ADT: 10,953

FM

Poor

Over: SHANCTON CREEK

067220501, Wayne, IA

Built 1970 Load: 38.0 t ADT: 310

E66

Poor

Over: PLAGUE MINE CREEK

082131603, Tama, IA

Built 1976 Load: 38.3 t ADT: 638

D-25

Poor

Over: SMALL NATURAL STREAM

088472408, Woodbury, IA

Built 1959 Load: 38.5 t ADT: 1,207

IA 175

Poor

Over: DRAINAGE DITCH #52

0.8 mi. E of jct SR P29, Webster, IA

Built 1953 Load: 38.6 t ADT: 960

MAIN ST

Poor

Over: AURELIA CREEK

091391001, Cherokee, IA

Built 1939 Load: 39.0 t ADT: 841

X AVE

Poor

Over: LITTLE BEAVER CREEK

084292502, Greene, IA

Built 1924 Load: 39.0 t ADT: 30

FM

Poor

Over: CHARITON RIVER

071203302, Lucas, IA

Built 1970 Load: 39.0 t ADT: 310

FM

Poor

Over: NORTH WALNUT CREEK

081140104, Poweshiek, IA

Built 1990 Load: 39.0 t ADT: 650

FM

Poor

Over: MINOR CREEK

099100604, Winneshiek, IA

Built 1970 Load: 39.0 t ADT: 88

IRR-FM

Poor

Over: BENNETT CREEK

083153104, Tama, IA

Built 1944 Load: 39.2 t ADT: 59

IA 2

Poor

Over: PLATTE RIVER

0.5 mi. E of W Jct SR N64, Taylor, IA

Built 1976 Load: 39.5 t ADT: 800

FM

Poor

Over: VILLAGE CREEK

071140504, Wapello, IA

Built 1989 Load: 39.5 t ADT: 90

216TH AVE

Poor

Over: SMALL CREEK

086E31702, Jackson, IA

Built 2000 Load: 39.6 t ADT: 60

LOCAL/730TH LN

Poor

Over: WATERWAY

077340504, Cass, IA

Built 1995 Load: 39.7 t ADT: 5

LOCAL

Poor

Over: CREEK

088022005, Dubuque, IA

Built 1997 Load: 39.8 t ADT: 130

FM

Poor

Over: CARTER CK

067131704, Davis, IA

Built 1973 Load: 40.2 t ADT: 290

1290 190TH ST

Poor

Over: WEST IOWA RIVER

095252401, Hancock, IA

Built 1957 Load: 40.2 t ADT: 26

FM

Poor

Over: MUD CREEK

078010506, Muscatine, IA

Built 1971 Load: 40.2 t ADT: 1,580

US 169

Poor

Over: BASS CREEK

0.6 mi. S of jct. SR C56, Webster, IA

Built 1958 Load: 40.5 t ADT: 4,680

150TH

Poor

Over: BEAVER DAM CREEK

094211201, Cerro Gordo, IA

Built 1961 Load: 41.0 t ADT: 687

LOCAL

Poor

Over: CREEK

085E32903, Jackson, IA

Built 1911 Load: 41.5 t ADT: 45

287TH ST

Poor

Over: LYTLE CREEK

086E20603, Jackson, IA

Built 1986 Load: 41.5 t ADT: 40

D-25

Poor

Over: CAMP CREEK

087460305, Woodbury, IA

Built 1978 Load: 41.7 t ADT: 977

LOCAL

Poor

Over: SMALL

099083205, Winneshiek, IA

Built 1978 Load: 41.9 t ADT: 11

50TH ST

Poor

Over: SMALL STREAM

084E71903, Jackson, IA

Built 1986 Load: 42.1 t ADT: 40

FIR

Poor

Over: BEAVER DAM CREEK

095221204, Cerro Gordo, IA

Built 1927 Load: 42.2 t ADT: 21

Showing 19,251-19,300 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.