State profile · Above national median SD

South Dakota bridge safety

Condition ratings, load ratings, and structural-deficiency data for every public highway bridge in South Dakota — drawn straight from the FHWA National Bridge Inventory.

5,905
Public bridges
31.9%
Good condition
16.2%
Poor condition
16.2%
Structurally deficient

Total Bridges

5,905

Public highway bridges in South Dakota

Good Condition

31.9%

1,885 bridges rated 7-9

-18.1pp vs 50% benchmark

Poor Condition

16.2%

959 bridges rated 0-4

Structurally Deficient

16.2%

959 bridges flagged for repair priority

9.2pp vs national avg 7.0%

South Dakota vs national bridge condition

South Dakota — Good condition share 31.9%
National avg

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

South Dakota — Structurally deficient share 54.1%
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 — South Dakota (FHWA NBI)

South Dakota31.922099915325997%44.06435224386113%16.240474174428453%16.240474174428453%GoodFairPoorStructurally Deficient
Bridge inventory deck-condition mix — South Dakota (FHWA NBI)

Counties (66)

Aurora 61 Beadle 153 Bennett 15 Bon Homme 126 Brookings 234 Brown 170 Brule 38 Buffalo 25 Butte 143 Campbell 15 Charles Mix 103 Clark 21 Clay 94 Codington 74 Corson 49 Custer 95 Davison 125 Day 37 Deuel 72 Dewey 28 Douglas 44 Edmunds 20 Fall River 80 Faulk 46 Grant 205 Gregory 51 Haakon 69 Hamlin 62 Hand 126 Hanson 62 Harding 49 Hughes 41 Hutchinson 161 Hyde 23 Jackson 89 Jerauld 35 Jones 37 Kingsbury 35 Lake 79 Lawrence 136 Lincoln 207 Lyman 114 Marshall 39 McCook 98 McPherson 14 Meade 217 Mellette 28 Miner 64 Minnehaha 395 Moody 87 Oglala Lakota 34 Pennington 350 Perkins 60 Potter 24 Roberts 157 Sanborn 53 Spink 176 Stanley 37 Sully 31 Todd 24 Tripp 90 Turner 143 Union 172 Walworth 34 Yankton 99 Ziebach 30

South Dakota 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 South Dakota on the same metric.

66

Guam

15.25% top marginal rate
Structure
Progressive
Burden @ $100K
$59

54

West Virginia

16.02% top marginal rate
Structure
Progressive
Burden @ $100K
$7,679
Selected

46

South Dakota

16.24% top marginal rate
Structure
Progressive
Burden @ $100K
$5,905

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 South Dakota

Six lowest-condition bridges in South Dakota, ranked by composite NBI rating. Each is inspected at least every 24 months.

483 AVENUE

Structurally Deficient

Over: WHETSTONE RV

4.8E & 3.2N MILBANK, Grant, SD

Built 1962 Load: 0.9 t ADT: 25

202ND ST.

Structurally Deficient

Over: BEAR BUTTE CK

5.3E BEAR BUTTE, Meade, SD

Built 2000 Load: 0.9 t ADT: 50

45980 303 ST.

Structurally Deficient

Over: VERMILLION RV

6S & 7.8E IRENE, Clay, SD

Built 1909 Load: 1.8 t ADT: 15

460th Avenue

Structurally Deficient

Over: Big Coulee Creek

4S & 2W of Peever, Roberts, SD

Built 1950 Load: 2.2 t ADT: 22

197TH ST

Structurally Deficient

Over: TURTLE CK

1N & 1E ST LAWRENCE, Hand, SD

Built 1925 Load: 2.5 t ADT: 25

242 ST

Structurally Deficient

Over: CK

1.8E 11.0N PLANKINTON, Aurora, SD

Built 1917 Load: 2.7 t ADT: 101

All Bridges in South Dakota

29970 457 AVE.

Good

Over: SPRING CK

2.7S & 5E IRENE, Clay, SD

Built 1988 Load: 35.4 t ADT: 25

472A AVENUE

Good

Over: CK

5.5W & 8.4N TORONTO, Deuel, SD

Built 2020 Load: 35.4 t ADT: 19

369TH AVE

Good

Over: SOUTH FORK SNAKE CK

3W & 9.8N ZELL, Faulk, SD

Built 1997 Load: 35.4 t ADT: 36

41880 262 AVENUE

Good

Over: JAMES RV

5S & 2.3W ALEXANDRIA, Hanson, SD

Built 1971 Load: 35.4 t ADT: 60

I090 W

Good

Over: R&W RR

2.6 E OKATON INTERCH, Jones, SD

Built 1969 Load: 35.4 t ADT: 3,360

SD019

Good

Over: TRIB TO LONG LAKE

5.5 SE JCT SD 34, Lake, SD

Built 2014 Load: 35.4 t ADT: 1,586

NORTH HAINES AVE.

Good

Over: ELK CK

14E&12.4S STURGIS, Meade, SD

Built 2020 Load: 35.4 t ADT: 33

US012

Good

Over: BURLINGTON NORTHERN RR

0.9 W JCT SD 15, Grant, SD

Built 2013 Load: 35.5 t ADT: 2,317

SD034

Good

Over: NORTH PLUM CK

9.1 W STANLEY CO LINE, Haakon, SD

Built 1959 Load: 35.5 t ADT: 364

SD100

Good

Over: BIG SIOUX & BNSF RR

0.6 S I90 INTERCHANGE SF, Minnehaha, SD

Built 2020 Load: 35.5 t

SD100

Good

Over: BIG SIOUX & BNSF RR

0.6 S I90 INTERCHANGE SF, Minnehaha, SD

Built 2020 Load: 35.5 t

247th Street

Good

Over: W. Fork of Vermillion Rv

0.3E of Unityville, McCook, SD

Built 2010 Load: 35.6 t ADT: 243

363rd Avenue

Good

Over: Foot Creek

0.2N of Leola, McPherson, SD

Built 2021 Load: 35.6 t ADT: 218

478th Avenue

Good

Over: Big Sioux River

1S of Egan, Moody, SD

Built 1994 Load: 35.6 t ADT: 430

404TH AVE

Good

Over: FOSTER CREEK

2W & 2.6N BLOOMFIELD, Spink, SD

Built 2020 Load: 35.6 t ADT: 31

393 AVE

Good

Over: CK

1.5N & 4.2W Mt Vernon, Aurora, SD

Built 2023 Load: 35.7 t ADT: 40

111th Street

Good

Over: Elm River

3N & 6.8W of Barnard, Brown, SD

Built 2000 Load: 35.7 t ADT: 98

167th Street

Good

Over: Big Sioux River

4S & 1.4E of Castlewood, Hamlin, SD

Built 1982 Load: 35.7 t ADT: 66

462nd Avenue

Good

Over: Big Sioux River

1W & 0.8S of Dempster, Hamlin, SD

Built 1992 Load: 35.7 t ADT: 66

195th Street

Good

Over: Big Sioux River

1.0S & 0.6W of Estelline, Hamlin, SD

Built 1993 Load: 35.7 t ADT: 66

SD038

Good

Over: WEST FORK VERMILLION RV

1.5 W JCT US 81, McCook, SD

Built 2021 Load: 35.7 t ADT: 993

West 12th Street

Good

Over: Big Sioux River

0.2E of Lyons Avenue - SF, Minnehaha, SD

Built 1997 Load: 35.7 t ADT: 40,100

SD073

Good

Over: MOREAU RV

11.5 N MEADE CO LINE, Perkins, SD

Built 2016 Load: 35.7 t ADT: 452

30620 475TH AVE

Good

Over: CK

4W & 5.2S ALCESTER, Union, SD

Built 2022 Load: 35.7 t ADT: 125

146th Street

Good

Over: Mud Creek

3S & 1.1E of Stratford, Brown, SD

Built 1989 Load: 35.8 t ADT: 98

30440 452 AVE

Good

Over: CK

3W & 2.4S WAKONDA, Clay, SD

Built 2016 Load: 35.8 t ADT: 115

I029

Good

Over: NINE MILE CK

4.5 S MINNEHAHA CO LINE, Lincoln, SD

Built 1958 Load: 35.9 t ADT: 33,530

47560 312TH ST

Good

Over: CK

14S & 3.6E BERESFORD, Union, SD

Built 2007 Load: 35.9 t ADT: 30

45080 303 ST

Good

Over: Turkey Creek

3.5 N Volin, Yankton, SD

Built 2022 Load: 35.9 t ADT: 45

SD037

Good

Over: EMANUEL CK

2.8W & .2N OF SPRINGFIELD, Bon Homme, SD

Built 1970 Load: 36.0 t ADT: 726

IRR BIA RTE 1

Good

Over: EAGLES NEST CREEK

14.5 KM SE OF INTERIOR, Jackson, SD

Built 1987 Load: 36.0 t ADT: 146

OLD BELLE HWY

Good

Over: TRIB TO SPEARFISH CK

1.5 W 4.2 N SPEARFISH, Lawrence, SD

Built 2003 Load: 36.0 t ADT: 740

248th Street

Good

Over: Little Vermillion River

4.5N & 2.7E of Salem, McCook, SD

Built 2005 Load: 36.0 t ADT: 200

SD037

Good

Over: CK

2 N PARKSTON, Hutchinson, SD

Built 2000 Load: 36.1 t ADT: 3,337

474TH AVENUE

Good

Over: BIG SIOUX RIVER

1.8S & 0.4W DELL RAPIDS, Minnehaha, SD

Built 1997 Load: 36.1 t ADT: 27

FIFTH STREET

Good

Over: RAPID CK

0.1N 5TH ST & OMAHA - RC, Pennington, SD

Built 1974 Load: 36.1 t ADT: 11,270

280th Ave.

Good

Over: ANTELOPE CK

1.9S & 6E MISSION, Todd, SD

Built 1994 Load: 36.1 t ADT: 27

217th Street

Good

Over: S. Fork of Pearl Creek

9.0S & 1.3W of Cavour, Beadle, SD

Built 2022 Load: 36.2 t ADT: 56

359 AVE

Good

Over: SOUTH FORK SNAKE CK

6E & 1N FAULKTON, Faulk, SD

Built 2004 Load: 36.2 t ADT: 33

48510 299TH STR.

Good

Over: FINNIE CK

6.1E & 2N ALCESTER, Union, SD

Built 2020 Load: 36.2 t ADT: 185

DOUGLAS AVENUE

Good

Over: MARNE CREEK

DOUGLAS AVENUE - YANKTON, Yankton, SD

Built 1999 Load: 36.2 t ADT: 50

TWNSHP RD 474TH AV

Good

Over: Deer Creek

4 W & 0.7 S TORONTO, Deuel, SD

Built 2021 Load: 36.3 t ADT: 30

TWNSHP RD 170TH ST

Good

Over: CK

2.0N 3.9E TUNERVILLE, Deuel, SD

Built 2020 Load: 36.3 t ADT: 25

472 AVENUE

Good

Over: Trib to S Fork Whetstone

1E & 3.2N TWIN BROOKS, Grant, SD

Built 2021 Load: 36.3 t ADT: 332

WAGNER RD

Good

Over: BIG NASTY CK

0.4 S OF RALPH, Harding, SD

Built 2017 Load: 36.3 t ADT: 23

SD115

Good

Over: TRIB NINE MILE CK

1.5W & 1.2N HARRISBURG, Lincoln, SD

Built 2019 Load: 36.3 t ADT: 6,280

296th Street

Good

Over: Trib. to E Brule Creek

1N & 5.9E of Beresford, Lincoln, SD

Built 1990 Load: 36.3 t ADT: 45

I090 W

Good

Over: SPLIT ROCK CK

0.4 E SD 11 INTERCH, Minnehaha, SD

Built 2018 Load: 36.3 t ADT: 11,910

122nd Street

Good

Over: Little Minnesota River

8E & 3S of Sisseton, Roberts, SD

Built 2020 Load: 36.3 t ADT: 198

IRR BIA RTE 30

Good

Over: LITTLE WHITE RIVER

1.5MI W SPRING CRK SCHOOL, Todd, SD

Built 1994 Load: 36.3 t ADT: 158

Showing 4,001-4,050 of 5,905 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.