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

LOCAL

Good

Over: ELLIOTT CREEK

089452901, Woodbury, IA

Built 1993 Load: 35.6 t ADT: 15

FLOYD LINE ST.

Good

Over: STREAM

093170401, Butler, IA

Built 2001 Load: 35.7 t ADT: 29

LOCAL

Good

Over: LITTLE WAPSIPINICON RVR

096140103, Chickasaw, IA

Built 1990 Load: 35.7 t ADT: 30

158TH AVE

Good

Over: CREEK

081E12404, Clinton, IA

Built 2003 Load: 35.7 t ADT: 130

125TH ST.

Good

Over: ELK RIVER

083E61705, Clinton, IA

Built 2001 Load: 35.7 t ADT: 11

US 34 WB

Good

Over: BIG CREEK

0.7 mi. E of Jct. SR W55, Henry, IA

Built 2002 Load: 35.7 t ADT: 2,900

LOCAL

Good

Over: PRARIE CREEK

080202303, Jasper, IA

Built 2001 Load: 35.7 t ADT: 5

LOCAL ROAD

Good

Over: JOHNSON CREEK

098440701, Lyon, IA

Built 2005 Load: 35.7 t ADT: 30

FM

Good

Over: DRAINAGE DITCH

079240421, Polk, IA

Built 2005 Load: 35.7 t ADT: 3,755

248TH ST

Good

Over: DYE CREEK

083221408, Story, IA

Built 1980 Load: 35.7 t ADT: 71

LOCAL

Good

Over: NODAWAY RIVER DITCH

070350807, Taylor, IA

Built 1989 Load: 35.7 t ADT: 34

LOCAL

Good

Over: BRANCH MIDDLE RIVER

076252303, Warren, IA

Built 1999 Load: 35.7 t ADT: 91

LOCAL

Good

Over: N FORK BUFFALO CREEK

098261801, Winnebago, IA

Built 2011 Load: 35.7 t ADT: 71

LOCAL

Good

Over: DD# 107

093253001, Wright, IA

Built 1987 Load: 35.7 t ADT: 36

LOCAL

Good

Over: BRUSHY FORK CREEK

083350701, Carroll, IA

Built 1996 Load: 35.8 t ADT: 40

140TH ST

Good

Over: CREEK

096131001, Chickasaw, IA

Built 2000 Load: 35.8 t ADT: 30

200TH ST

Good

Over: SMALL STREAM

082E42701, Clinton, IA

Built 1976 Load: 35.8 t ADT: 51

IA 15

Good

Over: BLACK CAT CREEK

6.4 mi. S of IA 9, Emmet, IA

Built 1991 Load: 35.8 t ADT: 970

SB I-380

Good

Over: WEST BLUE CREEK

2.7 MI. N OF JCT SR W35, Linn, IA

Built 1982 Load: 35.8 t ADT: 10,750

FM

Good

Over: ENGLISH CREEK

074201605, Marion, IA

Built 1999 Load: 35.8 t ADT: 1,100

FA-360TH ST

Good

Over: INDIAN CREEK

072401904, Mills, IA

Built 1998 Load: 35.8 t ADT: 399

N54 DELTA AVE

Good

Over: BRANCH OF NODAWAY RVR

2.5 mi N of G27 on N54, Adair, IA

Built 2013 Load: 35.9 t ADT: 349

BARCLAY RD

Good

Over: POYNER CREEK

89-11-17-03-10, Black Hawk, IA

Built 1987 Load: 35.9 t ADT: 59

NEWELL ST

Good

Over: CAMP CREEK

89-11-23-01-10, Black Hawk, IA

Built 1988 Load: 35.9 t ADT: 44

LOCAL

Good

Over: SMALL STREAM

093180101, Butler, IA

Built 1992 Load: 35.9 t ADT: 25

160TH ST.

Good

Over: BROPHY CREEK

082E50505, Clinton, IA

Built 1990 Load: 35.9 t ADT: 41

130 STREET

Good

Over: WALNUT CREEK

070402303, Fremont, IA

Built 1988 Load: 35.9 t ADT: 35

FM

Good

Over: DOWD CREEK

087183402, Grundy, IA

Built 1998 Load: 35.9 t ADT: 29

COUNTY ROAD

Good

Over: BRANCH BEAVER CREEK

089180702, Grundy, IA

Built 1998 Load: 35.9 t ADT: 20

LOCAL

Good

Over: CREEK

086202702, Hardin, IA

Built 1996 Load: 35.9 t ADT: 25

LOCAL

Good

Over: CREEK

087193602, Hardin, IA

Built 1995 Load: 35.9 t ADT: 21

LOCAL

Good

Over: CREEK

089202103, Hardin, IA

Built 1995 Load: 35.9 t ADT: 285

FM 125TH ST

Good

Over: DRAINAGE DITCH

098110303, Howard, IA

Built 1973 Load: 35.9 t ADT: 128

EB IA 100

Good

Over: INDIAN CREEK

3.2 MI. W JCT. IA 13 &151, Linn, IA

Built 1995 Load: 35.9 t ADT: 11,050

FM

Good

Over: CREEK

079241501, Polk, IA

Built 2003 Load: 35.9 t ADT: 956

NE 47TH STREET

Good

Over: FOUR MILE CREEK

080240100, Polk, IA

Built 2006 Load: 35.9 t ADT: 89

CLAY ST

Good

Over: OVER IAIS RR

080142303, Poweshiek, IA

Built 2002 Load: 35.9 t ADT: 2,648

IRR BIA ROUTE 12

Good

Over: IOWA DRAINAGE DITCH

SETTLEMENT ROAD, Tama, IA

Built 2001 Load: 35.9 t ADT: 300

LOCAL ROAD

Good

Over: BRANCH MOSQUITO CREEK

086160101, Tama, IA

Built 2000 Load: 35.9 t ADT: 33

FM

Good

Over: RUNNING CREEK

097102706, Winneshiek, IA

Built 1977 Load: 35.9 t ADT: 34

LOCAL

Good

Over: SMALL CREEK

100083001, Winneshiek, IA

Built 1981 Load: 35.9 t ADT: 97

GIBBON AVE

Good

Over: MIDDLE RIVER

0.2 mi S of Co Line, Adair, IA

Built 2016 Load: 36.0 t ADT: 15

MAKEE DRIVE

Good

Over: VILLAGE CREEK

098052801, Allamakee, IA

Built 2022 Load: 36.0 t ADT: 157

FERRIS MILL RD

Good

Over: BR UPPER IOWA RIVER

099061904, Allamakee, IA

Built 2017 Load: 36.0 t ADT: 70

OAKLAND AVE

Good

Over: TRIB TO CRANE CREEK

092122802, Bremer, IA

Built 2022 Load: 36.0 t ADT: 20

YALE AVE

Good

Over: STREAM

092151302, Butler, IA

Built 2015 Load: 36.0 t ADT: 44

T47 PACKARD AVE

Good

Over: SMALL STREAM

Packard Ave. S. of 165th, Butler, IA

Built 2015 Load: 36.0 t ADT: 304

IA 24

Good

Over: EAST WAPSIPINICON RIVER

2.2 mi. E of Jct. SR B57, Chickasaw, IA

Built 2000 Load: 36.0 t ADT: 3,150

102ND AVE

Good

Over: CREEK

081E13106, Clinton, IA

Built 1991 Load: 36.0 t ADT: 26

STATE ST

Good

Over: OXLEY CREEK

0802612, Dallas, IA

Built 2016 Load: 36.0 t ADT: 1,379

Showing 13,001-13,050 of 20,753 bridges

Related

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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.