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

SCENIC RIVER RD

Good

Over: CREEK

.75 Mi W Bluffton Rd, Winneshiek, IA

Built 2015 Load: 34.3 t ADT: 26

LOCAL

Good

Over: STREAM

0894301, Woodbury, IA

Built 2001 Load: 34.3 t ADT: 20

LOCAL

Good

Over: SMALL STREAM

0894301, Woodbury, IA

Built 2002 Load: 34.3 t ADT: 20

RAMPS D & J

Good

Over: CEDAR RIVER OVERFLOW

AT JCT. OF IA. 58, Black Hawk, IA

Built 1995 Load: 34.4 t ADT: 8,400

260TH AVE.

Good

Over: DEEP CREEK

083E33502, Clinton, IA

Built 1984 Load: 34.4 t ADT: 47

LOCAL ROAD

Good

Over: TOM CREEK

1002431902, Lyon, IA

Built 2011 Load: 34.4 t ADT: 26

FM

Good

Over: WATERMAN CREEK

096391702, O'Brien, IA

Built 1937 Load: 34.4 t ADT: 1,057

LOCAL

Good

Over: BR OF CAMP CREEK

079221003, Polk, IA

Built 1993 Load: 34.4 t ADT: 468

FM-LOMBARDY RD

Good

Over: STREAM

00000, Pottawattamie, IA

Built 2011 Load: 34.4 t ADT: 71

SHORTSTOP AVE

Good

Over: MINOR DRAINAGE

077422503, Pottawattamie, IA

Built 2012 Load: 34.4 t ADT: 45

295TH AVE

Good

Over: SMALL CREEK

0.15 MI N of 120th St., Winneshiek, IA

Built 2011 Load: 34.4 t ADT: 79

FM

Good

Over: UPPER IOWA RIVER BRANCH

099092506, Winneshiek, IA

Built 1987 Load: 34.4 t ADT: 324

W 7TH

Good

Over: PERRY CREEK

000000000, Woodbury, IA

Built 1900 Load: 34.4 t ADT: 5,086

MARQUIS RD W

Good

Over: STREAM

90-13-04-01, Black Hawk, IA

Built 2012 Load: 34.5 t ADT: 20

200TH ST

Good

Over: CREEK

092132703, Bremer, IA

Built 2014 Load: 34.5 t ADT: 44

LOCAL 180 AVE

Good

Over: HONEY CREEK

089051602, Delaware, IA

Built 1984 Load: 34.5 t ADT: 1,030

IA 175

Good

Over: UP RR

0.5 MILE E OF E JCT US 69, Hamilton, IA

Built 1979 Load: 34.5 t ADT: 1,690

US 34 EB

Good

Over: BIG CREEK

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

Built 2002 Load: 34.5 t ADT: 2,900

E 132ND ST S

Good

Over: SMALL STREAM

079173404, Jasper, IA

Built 2018 Load: 34.5 t ADT: 41

INLET AVE

Good

Over: COON CREEK

080182303, Jasper, IA

Built 2018 Load: 34.5 t ADT: 21

US 151 & IA 13

Good

Over: OVER UP RR

1.2 MI. N of E Jct. US 30, Linn, IA

Built 1998 Load: 34.5 t ADT: 9,650

LOCAL

Good

Over: BALLINGER CREEK

076170204, Mahaska, IA

Built 1993 Load: 34.5 t ADT: 34

100TH ST

Good

Over: S.ENGLISH RIVER

077140201, Mahaska, IA

Built 1997 Load: 34.5 t ADT: 110

IRR LCL-SDB

Good

Over: IOWA RIVER OVERFLOW

083153007, Tama, IA

Built 1998 Load: 34.5 t

FINCH

Good

Over: WINNEBAGO RIVER

098223604, Worth, IA

Built 1995 Load: 34.5 t ADT: 47

FM-BIRCH AVENUE

Good

Over: MIDDLE NODAWAY RIVER

072352102, Adams, IA

Built 1985 Load: 34.6 t ADT: 26

LOCAL

Good

Over: ELKHORN CREEK

079363601, Audubon, IA

Built 1996 Load: 34.6 t ADT: 26

LOCAL

Good

Over: CREEK

081363504, Audubon, IA

Built 1998 Load: 34.6 t ADT: 30

E MARQUIS RD

Good

Over: PRINCIPAL

90-13-01-01, Black Hawk, IA

Built 2011 Load: 34.6 t ADT: 70

MIDWAY AVE

Good

Over: STREAM

091121902, Bremer, IA

Built 2001 Load: 34.6 t ADT: 59

170TH ST

Good

Over: STREAM

092141201, Bremer, IA

Built 1998 Load: 34.6 t ADT: 29

LOCAL

Good

Over: WEST FORK CEDAR RIVER

091171508, Butler, IA

Built 1995 Load: 34.6 t ADT: 11

100TH AVE

Good

Over: WILLOW CREEK

096383102, Clay, IA

Built 1996 Load: 34.6 t ADT: 35

IA 13

Good

Over: TURKEY RIVER

0.1 MI. N OF JCT. IA 56, Clayton, IA

Built 1982 Load: 34.6 t ADT: 2,800

280TH ST

Good

Over: SMALL STREAM

081E13109, Clinton, IA

Built 1993 Load: 34.6 t ADT: 30

270TH ST

Good

Over: BROPHY CREEK

081E53101, Clinton, IA

Built 1993 Load: 34.6 t ADT: 30

340TH AVENUE

Good

Over: BROPHY CREEK

081E53103, Clinton, IA

Built 1984 Load: 34.6 t ADT: 82

330TH AVE.

Good

Over: SMALL

082E43602, Clinton, IA

Built 1979 Load: 34.6 t ADT: 450

190TH ST.

Good

Over: BROPHYS CREEK

082E52203, Clinton, IA

Built 1983 Load: 34.6 t ADT: 113

200TH ST.

Good

Over: BROPHYS CREEK

082E52205, Clinton, IA

Built 1983 Load: 34.6 t ADT: 30

210TH ST.

Good

Over: BROPHY CREEK

082E53305, Clinton, IA

Built 1977 Load: 34.6 t ADT: 25

190TH ST.

Good

Over: MILL CREEK

082E62201, Clinton, IA

Built 1990 Load: 34.6 t ADT: 30

110TH ST.

Good

Over: ELWOOD CREEK

083E21001, Clinton, IA

Built 1971 Load: 34.6 t ADT: 82

185TH AVENUE

Good

Over: ELWOOD CREEK

083E21624, Clinton, IA

Built 1981 Load: 34.6 t ADT: 260

E-50 (140TH ST)

Good

Over: SO BRANCH ELK RIVER

083E62901, Clinton, IA

Built 1979 Load: 34.6 t ADT: 860

LOCAL

Good

Over: LITTLE FLOOD CREEK

095161803, Floyd, IA

Built 1995 Load: 34.6 t ADT: 20

VINE AVENUE

Good

Over: HARTGRAVES CREEK

092193402, Franklin, IA

Built 1993 Load: 34.6 t ADT: 47

220TH ST

Good

Over: LONE GROVE CREEK

079330101, Guthrie, IA

Built 2010 Load: 34.6 t ADT: 20

LOCAL

Good

Over: SMALL STREAM

087191202, Hardin, IA

Built 1999 Load: 34.6 t ADT: 35

LOCAL

Good

Over: BEAR CREEK

087192201, Hardin, IA

Built 1991 Load: 34.6 t ADT: 30

Showing 12,701-12,750 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.