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

ROBIN AVE

Good

Over: DRAINAGE DITCH

099121202, Howard, IA

Built 2018 Load: 54.1 t ADT: 73

LCL-370TH ST

Good

Over: DEER CREEK

071402002, Mills, IA

Built 2005 Load: 54.2 t ADT: 15

LOCAL

Good

Over: DRAINAGE

072180216, Monroe, IA

Built 2002 Load: 54.2 t ADT: 11

US 61 SB

Good

Over: TARE COD CREEK

1.4 MI. N OF JCT. SR E17, Jackson, IA

Built 1996 Load: 54.3 t ADT: 4,050

N46 150TH ST

Good

Over: SOUTH RACCOON RIVER

081333203, Guthrie, IA

Built 2020 Load: 54.4 t ADT: 399

FM 3150 TAYLOR

Good

Over: WINNEBAGO RIVER

097231704, Hancock, IA

Built 1992 Load: 54.4 t ADT: 90

70TH ST

Good

Over: DRAINAGE DITCH

099121103, Howard, IA

Built 2018 Load: 54.4 t ADT: 35

US 52

Good

Over: BEAVER CREEK

3.1 MI. N OF JCT. IA 64, Jackson, IA

Built 1984 Load: 54.4 t ADT: 930

I 35

Good

Over: TRIB TO FOUR MILE CREEK

0.8 MI. N OF E 1ST ST, Polk, IA

Built 2018 Load: 54.4 t ADT: 56,800

IA 81

Good

Over: BIG INDIAN CREEK

0.1 Mi. S of Jct. IA 2, Van Buren, IA

Built 1989 Load: 54.4 t ADT: 650

FM-450TH STREET

Good

Over: GREYBILL CREEK

075390302, Pottawattamie, IA

Built 1974 Load: 54.5 t ADT: 60

FM-MAHOGANY RD

Good

Over: SIMON RUN

076431803, Pottawattamie, IA

Built 1976 Load: 54.5 t ADT: 199

LOCAL

Good

Over: SMALL STREAM

095152601, Floyd, IA

Built 1987 Load: 54.6 t ADT: 29

IOWA AVE

Good

Over: ELK CREEK

T91,R4,S11, Clayton, IA

Built 2014 Load: 54.8 t ADT: 79

320TH AVE

Good

Over: CREEK

082E43502, Clinton, IA

Built 2021 Load: 54.8 t ADT: 26

LOCAL

Good

Over: PIERSON CREEK

0894233, Woodbury, IA

Built 2006 Load: 54.8 t ADT: 30

FM

Good

Over: LAKE CHANNEL

099362901, Dickinson, IA

Built 2006 Load: 55.1 t ADT: 4,040

SB US 61

Good

Over: PRAIRIE CREEK

2.0 mi. S of Jct Ia. 64, Jackson, IA

Built 1996 Load: 55.1 t ADT: 4,600

280TH ST

Good

Over: STREAM

080052103, Johnson, IA

Built 1993 Load: 55.1 t ADT: 50

US 61

Good

Over: CROW CREEK

2.2 MI. N OF JCT. I-80, Scott, IA

Built 1981 Load: 55.1 t ADT: 29,300

POPCORN RD

Good

Over: LITTLE RIVER

070251901, Decatur, IA

Built 2016 Load: 55.2 t ADT: 41

LOCAL

Good

Over: SALT CREEK

085143502, Tama, IA

Built 2003 Load: 55.2 t ADT: 5

FM

Good

Over: ELK HORN CREEK

078360405, Audubon, IA

Built 2002 Load: 55.3 t ADT: 20

IA 93

Good

Over: N.BR.VOLGA RIVER

1.3 MI. E OF S.R. W14, Fayette, IA

Built 1989 Load: 55.3 t ADT: 790

165 STREET

Good

Over: HUNTER BRANCH

069400503, Fremont, IA

Built 1991 Load: 55.3 t ADT: 11

SECRIST RD

Good

Over: SIMMONS CREEK

083050703, Linn, IA

Built 1989 Load: 55.3 t ADT: 1,660

250TH AVE

Good

Over: CLEAR CREEK

081E31504, Clinton, IA

Built 2022 Load: 55.4 t ADT: 35

350TH AVE

Good

Over: CHERRY CREEK

081E51702, Clinton, IA

Built 2006 Load: 55.5 t ADT: 80

S 60TH AVE W

Good

Over: SMALL STREAM

079202601, Jasper, IA

Built 2016 Load: 55.5 t ADT: 26

FM SW ANGLE AVE

Good

Over: DEER CREEK

078083209, Johnson, IA

Built 1995 Load: 55.5 t ADT: 140

108TH PLACE

Good

Over: ENGLISH CREEK

075202602, Marion, IA

Built 2016 Load: 55.5 t ADT: 51

E22 61ST ST

Good

Over: PRATT CREEK

085123501, Benton, IA

Built 2015 Load: 55.7 t ADT: 334

OSAGE RD

Good

Over: TRIB TO INDIAN CREEK

89-11-32-01-10, Black Hawk, IA

Built 2005 Load: 55.7 t ADT: 88

110TH ST

Good

Over: TRIB OF SQUAW CREEK

085251001, Boone, IA

Built 2018 Load: 55.7 t ADT: 30

IOWA SPEEDWAY DR

Good

Over: CARSON CREEK

000000000, Jasper, IA

Built 2005 Load: 55.7 t ADT: 304

FM

Good

Over: WINNEBAGO RIVER

099242503, Winnebago, IA

Built 1989 Load: 55.9 t ADT: 90

LOCAL

Good

Over: WINNEBAGO RIVER

099243601, Winnebago, IA

Built 1993 Load: 55.9 t ADT: 30

US 18 EB

Good

Over: LITTLE LIME CREEK

1.6 mi. E of S.R. S56, Cerro Gordo, IA

Built 1997 Load: 56.0 t ADT: 5,500

IA 136

Good

Over: FARM CREEK

5.4 MI. S OF JCT. US #151, Jones, IA

Built 1986 Load: 56.0 t ADT: 770

IA 10

Good

Over: BIG CEDAR CREEK

0.2 W of E jct SR N28, Pocahontas, IA

Built 1987 Load: 56.0 t ADT: 1,200

SB US 61

Good

Over: SILVER CREEK

6.4 mi. S of Jct. IA #136, Clinton, IA

Built 1996 Load: 56.1 t ADT: 4,600

LOCAL

Good

Over: TRIB S FORK ENGLISH RVR

077100404, Keokuk, IA

Built 1987 Load: 56.2 t ADT: 45

FM

Good

Over: BEAVER CREEK

090162702, Butler, IA

Built 2003 Load: 56.3 t ADT: 960

FM 290 ST.

Good

Over: BEAR CREEK

087090901, Buchanan, IA

Built 2004 Load: 56.4 t ADT: 344

195TH ST

Good

Over: MILL CREEK

082E62203, Clinton, IA

Built 2017 Load: 56.4 t ADT: 51

125TH AVE

Good

Over: STREAM

077200104, Marion, IA

Built 2017 Load: 56.4 t ADT: 47

1770 190TH ST

Good

Over: EAST BRANCH IA RIVER

095242301, Hancock, IA

Built 1993 Load: 56.5 t ADT: 50

165TH STREET

Good

Over: SILVER CREEK (WEST)

082E30505, Clinton, IA

Built 2006 Load: 56.6 t ADT: 62

S 12TH AVE E

Good

Over: N SKUNK RIVER

079170501, Jasper, IA

Built 2005 Load: 56.6 t ADT: 35

FARM

Good

Over: SMALL STREAM

068232504, Wayne, IA

Built 2002 Load: 56.6 t ADT: 40

Showing 16,151-16,200 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.