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

320TH ST

Good

Over: STRAM

078331901, Guthrie, IA

Built 2015 Load: 32.7 t ADT: 11

ZIEGLER AVE

Good

Over: BEAR CR

086232402, Hamilton, IA

Built 2012 Load: 32.7 t ADT: 60

380TH ST

Good

Over: LONG DICK CREEK

086232701, Hamilton, IA

Built 2000 Load: 32.7 t ADT: 797

FM

Good

Over: LONG DICK CREEK

086233504, Hamilton, IA

Built 1997 Load: 32.7 t ADT: 559

LOCAL

Good

Over: KEIGLEY CREEK

086252201, Hamilton, IA

Built 1994 Load: 32.7 t ADT: 50

FM

Good

Over: KEIGLEY CREEK

086252501, Hamilton, IA

Built 1999 Load: 32.7 t ADT: 589

LOCAL

Good

Over: PRAIRIE CR

087262003, Hamilton, IA

Built 2006 Load: 32.7 t ADT: 26

FM

Good

Over: DRAINAGE DITCH

088233601, Hamilton, IA

Built 2005 Load: 32.7 t ADT: 265

LOCAL

Good

Over: DRAINAGE DITCH

088241402, Hamilton, IA

Built 2011 Load: 32.7 t ADT: 11

240TH ST

Good

Over: DRAINAGE DITCH

088241501, Hamilton, IA

Built 2011 Load: 32.7 t ADT: 50

TOLLMAN AVE

Good

Over: DRAINAGE DITCH

088242402, Hamilton, IA

Built 2012 Load: 32.7 t ADT: 45

FM

Good

Over: BREWERS CREEK

088261003, Hamilton, IA

Built 1978 Load: 32.7 t ADT: 131

160TH ST

Good

Over: DRAINAGE DITCH

089230201, Hamilton, IA

Built 2010 Load: 32.7 t ADT: 30

170TH ST

Good

Over: DRAINAGE DITCH

089230801, Hamilton, IA

Built 2012 Load: 32.7 t ADT: 11

LOCAL

Good

Over: DRAINAGE DITCH

089231003, Hamilton, IA

Built 2005 Load: 32.7 t ADT: 11

LOCAL

Good

Over: BUCK CR

089250103, Hamilton, IA

Built 2008 Load: 32.7 t ADT: 26

175TH ST

Good

Over: BUCK CREEK

089251203, Hamilton, IA

Built 2000 Load: 32.7 t ADT: 30

FM 2160 SIOUX

Good

Over: D.D.#5

095230604, Hancock, IA

Built 1987 Load: 32.7 t ADT: 230

FM 2080 SIOUX

Good

Over: GOLLS CREEK

095230704, Hancock, IA

Built 1991 Load: 32.7 t ADT: 230

FM 1930 YALE

Good

Over: GOLLS CREEK

095231302, Hancock, IA

Built 2010 Load: 32.7 t ADT: 20

LOC 2340 200TH

Good

Over: GOLLS CREEK

095231401, Hancock, IA

Built 2011 Load: 32.7 t ADT: 21

LOC 2240 200TH

Good

Over: GOLLS CREEK

095231501, Hancock, IA

Built 2007 Load: 32.7 t ADT: 21

LOC 2280 200TH

Good

Over: GOLLS CREEK

095231501, Hancock, IA

Built 2007 Load: 32.7 t ADT: 21

190TH ST

Good

Over: GOLLS CREEK DD177

095232401, Hancock, IA

Built 2021 Load: 32.7 t ADT: 11

LOC 1620 TAFT

Good

Over: DRAINAGE DITCH 9

095233212, Hancock, IA

Built 2010 Load: 32.7 t ADT: 235

B36 (225TH ST)

Good

Over: DRAINAGE DITCH 5

096233203, Hancock, IA

Built 2013 Load: 32.7 t ADT: 851

205TH ST

Good

Over: BEAVER CREEK

088202703, Hardin, IA

Built 2012 Load: 32.7 t ADT: 11

LOC TAMA TRAIL

Good

Over: S PICAYUNE CREEK

080412106, Harrison, IA

Built 1998 Load: 32.7 t ADT: 5

RACINE TRAIL

Good

Over: SMALL STREAM

000000000, Harrison, IA

Built 2009 Load: 32.7 t ADT: 139

296TH ST

Good

Over: POTATO CREEK

078420903, Harrison, IA

Built 2007 Load: 32.7 t ADT: 270

EASTON TRAIL

Good

Over: ELK CREEK

080430205, Harrison, IA

Built 2008 Load: 32.7 t ADT: 335

US 30

Good

Over: UPRR

0.8 mi. E of Jct I-29, Harrison, IA

Built 1998 Load: 32.7 t ADT: 10,300

LOCAL

Good

Over: FISH CREEK

070060706, Henry, IA

Built 1993 Load: 32.7 t ADT: 41

LEXINGTON AVE

Good

Over: DRAINAGE DITCH

070061306, Henry, IA

Built 2011 Load: 32.7 t ADT: 140

FREEMONT AVE

Good

Over: FISH CREEK

700618, Henry, IA

Built 2011 Load: 32.7 t ADT: 47

OLD HIGHWAY 34

Good

Over: SKUNK RIVER

071070301, Henry, IA

Built 2000 Load: 32.7 t ADT: 450

HENRYJEFFERSON AVE

Good

Over: STREAM

071070702, Henry, IA

Built 2022 Load: 32.7 t ADT: 26

HENRY JEFF AVE

Good

Over: BERRY BRANCH

071071902, Henry, IA

Built 2017 Load: 32.7 t ADT: 20

LOCAL

Good

Over: NORTH BRANCH BIG CREEK

072052904, Henry, IA

Built 1979 Load: 32.7 t ADT: 51

270TH ST

Good

Over: BRANCH OF BRUSH CREEK

071053201, Henry, IA

Built 2022 Load: 32.7 t ADT: 26

US 34 EB US 218 SB

Good

Over: BNSF RR

0.3 mi. W of E Jct.US 218, Henry, IA

Built 2001 Load: 32.7 t ADT: 4,400

180TH ST

Good

Over: TURKEY RIVER

097120101, Howard, IA

Built 2002 Load: 32.7 t ADT: 35

200TH ST

Good

Over: BR CRANE CREEK

097121701, Howard, IA

Built 1995 Load: 32.7 t ADT: 79

180TH ST

Good

Over: BR LITTLE WAPSIPINICON

097140101, Howard, IA

Built 2003 Load: 32.7 t ADT: 51

FM

Good

Over: SMALL STREAM

098110403, Howard, IA

Built 1995 Load: 32.7 t ADT: 79

FM 150TH ST

Good

Over: TURKEY RIVER

098112401, Howard, IA

Built 2009 Load: 32.7 t ADT: 766

PINE AVE

Good

Over: TURKEY RIVER

098120302, Howard, IA

Built 2002 Load: 32.7 t ADT: 51

ROBIN AVE

Good

Over: TURKEY RIVER

098123604, Howard, IA

Built 2000 Load: 32.7 t ADT: 108

LOCAL FIR AVE

Good

Over: DRAINAGE DITCH

098142402, Howard, IA

Built 2001 Load: 32.7 t ADT: 35

FM WILLOW AVE

Good

Over: SILVVER CREEK

099111404, Howard, IA

Built 2002 Load: 32.7 t ADT: 1,218

Showing 11,601-11,650 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.