State profile · Above median Poor share

Iowa bridge safety

According to the Federal Highway Administration's 2024 National Bridge Inventory, condition ratings, load ratings, and Poor-condition shares for every public highway bridge in Iowa.

23,719
Public bridges
38.8%
Good condition
19.2%
Poor condition

Iowa holds 23,719 public highway bridges (#7 of 52 by inventory) with a 19.16% Poor share (#1 of 52 by Poor share).

That is 19.2% of the state's inventory, against an average of 7.5% across the 54 states and territories with Poor-rated bridges on file, which places it 53 of 54 ordered from the lowest Poor share upward. A bridge is rated Poor when its weakest applicable component scores 4 or below on the inspecting agency's 0-9 scale, so the category is a maintenance and funding signal rather than a closure order or a live crossing-safety verdict.

Inventory: FHWA NBI 2024 · last ETL August 2026

Total Bridges

23,719

Public highway bridges in Iowa

Good Condition

38.8%

9,213 bridges rated 7-9

-11.2pp vs 50% benchmark

Poor Condition

19.2%

4,544 bridges whose lowest applicable component is rated 0-4

11.6pp vs national avg 7.5%

Iowa vs national bridge condition

Iowa - Good condition share 38.8%
National avg

Share of bridges rated 7-9 on the FHWA 0-9 scale (deck, superstructure, substructure all good).

Iowa - Poor-condition share 63.9%
National avg

Lower is better. Bar maxes at 30% (worst-state ceiling). National average sits at 7.5%.

Iowa in the national condition pattern

Each point is a state or territory in the FHWA NBI; the highlighted point is this profile.

Inventory size and Poor-condition share are different measures: Iowa has 23,719 bridges and a 19.2% Poor-condition share in the 2024 NBI, rank #53 of 54 jurisdictions ordered from the lowest share upward. The dashed comparisons mark the national average state rate and the midpoint of the plotted inventory range; neither is a live safety or closure threshold. Scatter plot of 54 data points. 0%10%20%30%40% 0k20k40k60k Public bridges in inventory (thousands) Poor-condition share (%) IA, Public bridges in inventory (thousands): 23.7k · Poor-condition share (%): 19.16%AL, Public bridges in inventory (thousands): 16.2k · Poor-condition share (%): 3.35%AK, Public bridges in inventory (thousands): 1.7k · Poor-condition share (%): 7.89%AZ, Public bridges in inventory (thousands): 8.6k · Poor-condition share (%): 1.15%AR, Public bridges in inventory (thousands): 13k · Poor-condition share (%): 5.43%CA, Public bridges in inventory (thousands): 25.8k · Poor-condition share (%): 5.91%CO, Public bridges in inventory (thousands): 9k · Poor-condition share (%): 4.82%CT, Public bridges in inventory (thousands): 4.4k · Poor-condition share (%): 4.72%DE, Public bridges in inventory (thousands): 0.9k · Poor-condition share (%): 1.26%DC, Public bridges in inventory (thousands): 0.3k · Poor-condition share (%): 1.95%FL, Public bridges in inventory (thousands): 13k · Poor-condition share (%): 2.79%GA, Public bridges in inventory (thousands): 15.1k · Poor-condition share (%): 1.59%GU, Public bridges in inventory (thousands): 0k · Poor-condition share (%): 12.77%HI, Public bridges in inventory (thousands): 1.2k · Poor-condition share (%): 6.53%ID, Public bridges in inventory (thousands): 4.6k · Poor-condition share (%): 4.9%IL, Public bridges in inventory (thousands): 26.9k · Poor-condition share (%): 9.35%IN, Public bridges in inventory (thousands): 19.5k · Poor-condition share (%): 5.22%KS, Public bridges in inventory (thousands): 24.9k · Poor-condition share (%): 5.26%KY, Public bridges in inventory (thousands): 14.5k · Poor-condition share (%): 7.37%LA, Public bridges in inventory (thousands): 12.7k · Poor-condition share (%): 11.48%ME, Public bridges in inventory (thousands): 2.5k · Poor-condition share (%): 15.41%MD, Public bridges in inventory (thousands): 5.5k · Poor-condition share (%): 4.56%MA, Public bridges in inventory (thousands): 5.3k · Poor-condition share (%): 8.88%MI, Public bridges in inventory (thousands): 11.4k · Poor-condition share (%): 11.27%MN, Public bridges in inventory (thousands): 13.5k · Poor-condition share (%): 4.44%MS, Public bridges in inventory (thousands): 16.7k · Poor-condition share (%): 6.03%MO, Public bridges in inventory (thousands): 24.6k · Poor-condition share (%): 8.95%MT, Public bridges in inventory (thousands): 5.2k · Poor-condition share (%): 6.81%NE, Public bridges in inventory (thousands): 15.4k · Poor-condition share (%): 7.9%NV, Public bridges in inventory (thousands): 2.1k · Poor-condition share (%): 1.14%NH, Public bridges in inventory (thousands): 2.5k · Poor-condition share (%): 7.51%NJ, Public bridges in inventory (thousands): 6.8k · Poor-condition share (%): 6.01%NM, Public bridges in inventory (thousands): 4k · Poor-condition share (%): 4.51%NY, Public bridges in inventory (thousands): 17.6k · Poor-condition share (%): 9.43%NC, Public bridges in inventory (thousands): 19.2k · Poor-condition share (%): 6.76%ND, Public bridges in inventory (thousands): 4.3k · Poor-condition share (%): 10.98%OH, Public bridges in inventory (thousands): 26.7k · Poor-condition share (%): 4.74%OK, Public bridges in inventory (thousands): 22.9k · Poor-condition share (%): 7.7%OR, Public bridges in inventory (thousands): 8.3k · Poor-condition share (%): 4.61%PA, Public bridges in inventory (thousands): 23.3k · Poor-condition share (%): 12.58%PR, Public bridges in inventory (thousands): 2.4k · Poor-condition share (%): 13.92%RI, Public bridges in inventory (thousands): 0.8k · Poor-condition share (%): 15.2%SC, Public bridges in inventory (thousands): 9.5k · Poor-condition share (%): 6.17%SD, Public bridges in inventory (thousands): 5.9k · Poor-condition share (%): 16.36%TN, Public bridges in inventory (thousands): 20.4k · Poor-condition share (%): 4.41%TX, Public bridges in inventory (thousands): 56.7k · Poor-condition share (%): 1.23%UT, Public bridges in inventory (thousands): 3.1k · Poor-condition share (%): 2.91%VT, Public bridges in inventory (thousands): 2.9k · Poor-condition share (%): 2.9%VI, Public bridges in inventory (thousands): 0k · Poor-condition share (%): 29.17%VA, Public bridges in inventory (thousands): 14.1k · Poor-condition share (%): 3.39%WA, Public bridges in inventory (thousands): 8.5k · Poor-condition share (%): 5.45%WV, Public bridges in inventory (thousands): 7.3k · Poor-condition share (%): 18.64%WI, Public bridges in inventory (thousands): 14.4k · Poor-condition share (%): 6.52%WY, Public bridges in inventory (thousands): 3.1k · Poor-condition share (%): 6.51%
Inventory size and Poor-condition share are different measures: Iowa has 23,719 bridges and a 19.2% Poor-condition share in the 2024 NBI, rank #53 of 54 jurisdictions ordered from the lowest share upward. The dashed comparisons mark the national average state rate and the midpoint of the plotted inventory range; neither is a live safety or closure threshold.

Iowa vs all states by public bridge inventory

Where this state's FHWA NBI public-highway bridge count sits among every state and territory on PlainBridges

23,719 7th of 54 higher than 47 of 54 states

States and territories, banded by public bridge inventory size

Each bar is a band; taller bars hold more states. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source FHWA National Bridge Inventory · 2024

Read the rank neighborhood for Iowa

The highlighted point is Iowa: 23,719 bridges and 19.16% in Poor condition, rank #53 of 54 jurisdictions ordered from the lowest share upward. The five jurisdictions immediately above and below Iowa on that same Poor-share ordering:

  • South Dakota: 5,887 bridges · 16.36% Poor
  • West Virginia: 7,348 bridges · 18.64% Poor
  • Iowa: 23,719 bridges · 19.16% Poor
  • Virgin Islands: 24 bridges · 29.17% Poor

The full national sortable table lives on the rankings page.

Material families in Iowa

Exclusive FHWA material families across all 23,719 bridges in this state; continuous variants fold into the parent family. Orthogonal to the Poor-share scatter above.

Who maintains Iowa’s inventory

State agency holds 17.7% of the 23,719 public highway bridges filed under Iowa in the 2024 NBI, the agency-of-record split for this state, not a condition verdict.

When Iowa’s bridges were built

Pre-1950 construction accounts for 12.4% of the 23,719 bridges with a recorded original year in Iowa. Era bands are orthogonal to the Poor-share ranking above.

Condition Distribution

Iowa38.8%42%19.2%GoodFairPoor
Bridge inventory deck-condition mix - Iowa (FHWA NBI)

Counties (99)

Adair 306 Adams 186 Allamakee 197 Appanoose 183 Audubon 206 Benton 374 Black Hawk 489 Boone 135 Bremer 266 Buchanan 316 Buena Vista 156 Butler 289 Calhoun 197 Carroll 249 Cass 295 Cedar 301 Cerro Gordo 266 Cherokee 248 Chickasaw 302 Clarke 168 Clay 151 Clayton 256 Clinton 372 Crawford 301 Dallas 199 Davis 165 Decatur 197 Delaware 293 Des Moines 176 Dickinson 84 Dubuque 346 Emmet 78 Fayette 362 Floyd 213 Franklin 228 Fremont 179 Greene 168 Grundy 289 Guthrie 263 Hamilton 165 Hancock 138 Hardin 241 Harrison 217 Henry 173 Howard 210 Humboldt 87 Ida 182 Iowa 241 Jackson 246 Jasper 382 Jefferson 157 Johnson 372 Jones 231 Keokuk 183 Kossuth 267 Lee 214 Linn 506 Louisa 151 Lucas 195 Lyon 276 Madison 225 Mahaska 225 Marion 217 Marshall 304 Mills 184 Mitchell 167 Monona 162 Monroe 130 Montgomery 210 Muscatine 144 O'Brien 264 Osceola 185 Page 196 Palo Alto 135 Plymouth 432 Pocahontas 201 Polk 545 Pottawattamie 557 Poweshiek 248 Ringgold 217 Sac 224 Scott 291 Shelby 207 Sioux 449 Story 296 Tama 337 Taylor 220 Union 169 Van Buren 156 Wapello 190 Warren 239 Washington 207 Wayne 163 Webster 190 Winnebago 55 Winneshiek 342 Woodbury 455 Worth 116 Wright 182

Iowa vs nearby ranks

Adjacent states by Poor-condition share (lower share = better)

States are ranked by the share of bridges whose lowest applicable component rating is 4 or below. This describes recorded condition; it does not measure funding effectiveness or live crossing safety. States here sit immediately above and below Iowa on the same metric.

SD

South Dakota

16.36% top marginal rate
Structure
Progressive
Burden @ $100K
$5,887

WV

West Virginia

18.64% top marginal rate
Structure
Progressive
Burden @ $100K
$7,348
Selected

IA

Iowa

19.16% top marginal rate
Structure
Progressive
Burden @ $100K
$23,719

VI

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 the portal's composite display score. Inspection intervals are risk-based under current NBIS rules.

MAIN ST

Poor

Over: IOWA RIVER

089211800, Hardin, IA

Built 1936 Load: 0.0 t ADT: 1,858

SO MAIN ST

Poor

Over: CASCADE LANDING

000000000, Des Moines, IA

Built 1896 Load: 0.0 t ADT: 743

E 13TH ST

Poor

Over: OVER I.C.E. RR

000000000, Scott, IA

Built 1900 Load: 0.0 t ADT: 358

EMERSON ST

Poor

Over: DRAINAGE

000000000, Madison, IA

Built 1965 Load: 0.0 t ADT: 396

1ST AVE S

Poor

Over: 21ST ST & RR

089282000, Webster, IA

Built 1968 Load: 0.0 t ADT: 9,860

1ST ST

Poor

Over: DRAINAGE

D60500515, Audubon, IA

Built 1930 Load: 0.0 t ADT: 9

All Bridges in Iowa

ODESSA AVE

Good

Over: EAST WAPSIPINICON RIVER

095121604, Chickasaw, IA

Built 2023 Load: 32.4 t ADT: 39

B54 240TH ST

Good

Over: E FORK WAPSIPINICON

095123603, Chickasaw, IA

Built 2017 Load: 32.4 t ADT: 511

B57 (220TH ST)

Good

Over: WAPSIPINICON

095131903, Chickasaw, IA

Built 2014 Load: 32.4 t ADT: 786

B33 170TH ST

Good

Over: CREEK

96132501, Chickasaw, IA

Built 2015 Load: 32.4 t ADT: 59

170TH ST

Good

Over: SMALL STREAM

096132801, Chickasaw, IA

Built 2021 Load: 32.4 t ADT: 88

T 76 CHEYENNE

Good

Over: WAPSIPINICON RIVER

096142202, Chickasaw, IA

Built 2019 Load: 32.4 t ADT: 98

EXETER

Good

Over: CREEK

096143602, Chickasaw, IA

Built 2018 Load: 32.4 t ADT: 73

NOLAN

Good

Over: CREEK

097122804, Chickasaw, IA

Built 2020 Load: 32.4 t ADT: 41

V 28 JASPER

Good

Over: BR E FK WAPSIPINICON

097132602, Chickasaw, IA

Built 2018 Load: 32.4 t ADT: 35

BEAUMONT AVE

Good

Over: BRANCH WAPSIPINICON RVR

97142802, Chickasaw, IA

Built 2016 Load: 32.4 t ADT: 47

115TH ST

Good

Over: BRANCH WAPSIPINICON RVR

097142903, Chickasaw, IA

Built 2017 Load: 32.4 t ADT: 29

ADDISON AVE

Good

Over: CREEK

097143102, Chickasaw, IA

Built 2019 Load: 32.4 t ADT: 29

H45 ELK ST

Good

Over: NORTH HOOSIER CREEK

071251005, Clarke, IA

Built 2021 Load: 32.4 t ADT: 79

160TH AVE

Good

Over: BEE CREEK

071260602, Clarke, IA

Built 2018 Load: 32.4 t ADT: 26

H45 ELK ST

Good

Over: BRANCH LONG CREEK

071271703, Clarke, IA

Built 2015 Load: 32.4 t ADT: 40

R15 130TH AVE

Good

Over: WEST LONG CREEK

071272202, Clarke, IA

Built 2021 Load: 32.4 t ADT: 219

R69 330TH AVE

Good

Over: OTTER CREEK

072240204, Clarke, IA

Built 2014 Load: 32.4 t ADT: 120

H20 PACIFIC ST

Good

Over: BRANCH OTTER CREEK

073242203, Clarke, IA

Built 2015 Load: 32.4 t ADT: 71

H28 MEADOW ST

Good

Over: NORTH OTTER CREEK

073253405, Clarke, IA

Built 2021 Load: 32.4 t ADT: 60

420TH ST

Good

Over: STREAM

095362201, Clay, IA

Built 2005 Load: 32.4 t ADT: 46

SEVEN DAY RD

Good

Over: SILVER CREEK(WEST)

082031501, Clinton, IA

Built 2017 Load: 32.4 t ADT: 80

120TH AVENUE

Good

Over: DD #23

083E13204, Clinton, IA

Built 2002 Load: 32.4 t ADT: 51

E46 200TH ST

Good

Over: PARADISE CREEK

083401507, Crawford, IA

Built 2017 Load: 32.4 t ADT: 21

120TH ST

Good

Over: EAST SOLDIER RIVER

084412804, Crawford, IA

Built 2016 Load: 32.4 t ADT: 30

UTE AVENUE

Good

Over: JOHNSON CREEK

078261704, Dallas, IA

Built 2013 Load: 32.4 t ADT: 2,071

156TH ST SB

Good

Over: WALNUT CREEK

200 ft North of Brookview, Dallas, IA

Built 2015 Load: 32.4 t ADT: 222

SPORTSMAN CLUB RD

Good

Over: CREEK

079271804, Dallas, IA

Built 2014 Load: 32.4 t ADT: 51

R30 130TH ST

Good

Over: BEAVER CREEK

081271001, Dallas, IA

Built 2017 Load: 32.4 t ADT: 329

MULBERRY AVE

Good

Over: SMALL STREAM

067130802, Davis, IA

Built 2017 Load: 32.4 t ADT: 20

ROBIN BVLD

Good

Over: S WYACONDAH DITCH

067131205, Davis, IA

Built 2018 Load: 32.4 t ADT: 50

MAHOGANY AVE

Good

Over: TRIB S WYACONDAH DITCH

068131902, Davis, IA

Built 2021 Load: 32.4 t ADT: 26

KEY BLVD

Good

Over: S WYACONDAH DITCH

68140204, Davis, IA

Built 2016 Load: 32.4 t ADT: 70

JEWEL AVE

Good

Over: S WYACONDAH DITCH

068140304, Davis, IA

Built 2020 Load: 32.4 t ADT: 30

JADE AVE

Good

Over: CARTER CREEK

068142702, Davis, IA

Built 2021 Load: 32.4 t ADT: 25

EBONY AVE

Good

Over: FABIUS CREEK

68153506, Davis, IA

Built 2016 Load: 32.4 t ADT: 45

192ND ST

Good

Over: FOX RIVER

069141803, Davis, IA

Built 2019 Load: 32.4 t ADT: 25

DRIFTWOOD BLVD

Good

Over: CREEK

069151506, Davis, IA

Built 2014 Load: 32.4 t ADT: 70

208TH ST

Good

Over: FOX RIVER

069152009, Davis, IA

Built 2019 Load: 32.4 t ADT: 30

CEDAR AVE

Good

Over: CENTER BRANCH FOX RIVER

069152102, Davis, IA

Built 2022 Load: 32.4 t ADT: 11

ECHO AVE

Good

Over: FOX RIVER

069152306, Davis, IA

Built 2014 Load: 32.4 t ADT: 50

CEDAR AVE

Good

Over: TRIB FOX RIVER

069152804, Davis, IA

Built 2021 Load: 32.4 t ADT: 15

APPLE AVE

Good

Over: TRIB S WYACONDAH DITCH

069153004, Davis, IA

Built 2017 Load: 32.4 t ADT: 20

PLEASANTON RD

Good

Over: MCGRUDER CREEK

068250406, Decatur, IA

Built 2015 Load: 32.4 t ADT: 329

R15 125TH AVE

Good

Over: GRAND RIVER

070271604, Decatur, IA

Built 2018 Load: 32.4 t ADT: 219

R15 125TH AVE

Good

Over: SAND CREEK

070272110, Decatur, IA

Built 2019 Load: 32.4 t ADT: 219

LOC 225 ST

Good

Over: SMALL STREAM

088040306, Delaware, IA

Built 1984 Load: 32.4 t ADT: 39

240TH ST

Good

Over: MAQUOKETA RIVER

00000, Delaware, IA

Built 2011 Load: 32.4 t ADT: 1,080

FM 140TH AVE

Good

Over: SAND CREEK

1.1 Mi. North of CR D34, Delaware, IA

Built 2011 Load: 32.4 t ADT: 49

310TH AVE

Good

Over: STREAM

89 03 10 0065, Delaware, IA

Built 2013 Load: 32.4 t ADT: 49

265TH AVE

Good

Over: PLUM CREEK

1 mile North of 195th St., Delaware, IA

Built 2012 Load: 32.4 t ADT: 15

Showing 12,051-12,100 of 23,719 bridges

Related

All states → | National rankings → | Understanding conditions → | Retired SD term explained →
Data sourced from the FHWA National Bridge Inventory (NBI), latest released cycle. See our methodology for details. Retrieved and formatted by PlainBridges.

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). Poor condition is an inspection-record category, not a closure or unsafe-to-cross designation. Consult the bridge owner for current status.

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.

What to do with this

Use Iowa's inventory picture to drill to a county or a specific span.

NBI condition ratings are inventory snapshots, not live crossing-safety verdicts.

Every figure on PlainBridges is rendered directly from federal source data, no number is typed in by an editor. Iowa Good/Fair/Poor shares and county rollups on this page are computed from the same NBI extract as the national boards; no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2024 NBI release. NBI condition categories reflect the latest reported inventory record, not a live safety, closure, or travel decision.