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

IRR BIA RTE N

Good

Over: TRIB OF MEDICINE ROOT CK

9.0 KM N OF SH 2, Oglala Lakota, SD

Built 2013 Load: 32.6 t ADT: 100

IRR BIA RTE N

Good

Over: TRIB OF MEDICINE ROOT CK

0.5 KM N OF SH 2, Oglala Lakota, SD

Built 2013 Load: 32.6 t ADT: 200

IRR BIA RTE 2

Good

Over: TRIB OF WHITE RIVER

5.2 KM E OF COUNTY LINE, Oglala Lakota, SD

Built 2016 Load: 32.6 t ADT: 100

BAD RIVER RD

Good

Over: BAD RV

7.9W & 5.8S OF FT. PIERRE, Stanley, SD

Built 1990 Load: 32.6 t ADT: 85

47440 298TH ST

Good

Over: WEST BRULE CK

2.6E BERESFORD, Union, SD

Built 2008 Load: 32.6 t ADT: 110

SD011

Good

Over: CK

4.6 S JCT SD 46, Union, SD

Built 1965 Load: 32.6 t ADT: 1,423

194th Street

Good

Over: Foster Creek

14.0N & 3.1E of Huron, Beadle, SD

Built 2011 Load: 32.7 t ADT: 56

30270 425th Avenue

Good

Over: Beaver Creek

8E of Tyndall, Bon Homme, SD

Built 2021 Load: 32.7 t ADT: 60

142nd Street

Good

Over: Mud Creek

3.5W of Ferney, Brown, SD

Built 2017 Load: 32.7 t ADT: 411

130th Street

Good

Over: Creek

3N & 5.8E of Groton, Brown, SD

Built 2006 Load: 32.7 t ADT: 402

REHORST ROAD

Good

Over: BELLE FOURCHE RV

2N 3W BELLE FOURCHE, Butte, SD

Built 2000 Load: 32.7 t ADT: 47

40410 307 ST

Good

Over: DRY CHOTEAU CK

7.0S,4.1E OF DANTE, Charles Mix, SD

Built 2019 Load: 32.7 t ADT: 34

South Dike Rd. / 2

Good

Over: LAKE ANDES

0.4 mi W of HQ, Charles Mix, SD

Built 2007 Load: 32.7 t ADT: 100

North Dike Rd / 28

Good

Over: Lake Andes

0.5 mi W of 389th Ave on, Charles Mix, SD

Built 2007 Load: 32.7 t ADT: 100

CITY STREET

Good

Over: BIG SIOUX RV

10TH AVE - WATERTOWN, Codington, SD

Built 1990 Load: 32.7 t ADT: 3,089

454 AVENUE

Good

Over: SOO CK

10W 0.8N SOUTHSHORE, Codington, SD

Built 1991 Load: 32.7 t ADT: 73

455 AVENUE

Good

Over: CK

4.4 N JCT US 212, Codington, SD

Built 1985 Load: 32.7 t ADT: 1,758

456 AVENUE

Good

Over: GRAVEL CK

5.3S,8W SOUTH SHORE, Codington, SD

Built 1997 Load: 32.7 t ADT: 73

461 AVENUE

Good

Over: GRAVEL CK

3W 3.1S SOUTH SHORE, Codington, SD

Built 1998 Load: 32.7 t ADT: 10

8TH ST IN CUSTER

Good

Over: FRENCH CK

EIGHTH ST. CUSTER, Custer, SD

Built 2014 Load: 32.7 t ADT: 330

CO RD 310 488TH AV

Good

Over: WEST BRANCH LA QUA PARLE

0.9 N GARY, Deuel, SD

Built 1992 Load: 32.7 t ADT: 20

453 AVENUE

Good

Over: Big Sioux River

11.7W & 1.8N MARVIN, Grant, SD

Built 2021 Load: 32.7 t ADT: 25

454 AVENUE

Good

Over: CK

10.7W & 2.1N MARVIN, Grant, SD

Built 2000 Load: 32.7 t ADT: 25

469 AVENUE

Good

Over: CK

4.3E & 3.4N MARVIN, Grant, SD

Built 2012 Load: 32.7 t ADT: 25

470 AVENUE

Good

Over: CK

5.3E & 2.6S MARVIN, Grant, SD

Built 2016 Load: 32.7 t ADT: 35

474TH AVE

Good

Over: CK

6.8S SD 20, Grant, SD

Built 2000 Load: 32.7 t ADT: 184

473 AVENUE

Good

Over: CK

5W & 5S MILBANK, Grant, SD

Built 2012 Load: 32.7 t ADT: 25

143 STREET

Good

Over: CK

6N & 4W MILBANK, Grant, SD

Built 2001 Load: 32.7 t ADT: 52

474 AVE

Good

Over: CK

3.0N & 4.0W MILBANK, Grant, SD

Built 2006 Load: 32.7 t ADT: 65

474 AVENUE

Good

Over: NORTH FORK YELLOW BANK R

4W & 4.6S MILBANK, Grant, SD

Built 2013 Load: 32.7 t ADT: 20

474 AVENUE

Good

Over: CK

2E & 5.7N STRANDBURG, Grant, SD

Built 2002 Load: 32.7 t ADT: 25

155 STREET

Good

Over: CK

4E & 2.5N STOCKHOLM, Grant, SD

Built 2000 Load: 32.7 t ADT: 70

475 AVENUE

Good

Over: SOUTH FORK WHETSTONE RV

3W & 0.3N MILBANK, Grant, SD

Built 2008 Load: 32.7 t ADT: 20

475 AVENUE

Good

Over: CK

3E & 5.8N STRANDBURG, Grant, SD

Built 2021 Load: 32.7 t ADT: 100

476 AVENUE

Good

Over: NORTH FORK YELLOW BANK R

2W & 3.9S MILBANK, Grant, SD

Built 2000 Load: 32.7 t ADT: 20

477TH AVE

Good

Over: CK

1W & 0.6S MILBANK, Grant, SD

Built 2000 Load: 32.7 t ADT: 30

477 AVENUE

Good

Over: NORTH FORK YELLOW BANK R

1W & 3.8S MILBANK, Grant, SD

Built 2007 Load: 32.7 t ADT: 35

156 STREET

Good

Over: CK

0.9E & 7S MILBANK, Grant, SD

Built 2007 Load: 32.7 t ADT: 35

479 AVENUE

Good

Over: CK

1E & 2.3N MILBANK, Grant, SD

Built 1996 Load: 32.7 t ADT: 52

480 AVENUE

Good

Over: CK

2.0E & 2.3N OF MILBANK, Grant, SD

Built 1993 Load: 32.7 t ADT: 65

480 AVENUE

Good

Over: CK

7S & 2E MILBANK, Grant, SD

Built 2002 Load: 32.7 t ADT: 52

480 AVENUE

Good

Over: SOUTH FORK YELLOW BANK R

1.5W & 1N REVILLO, Grant, SD

Built 2002 Load: 32.7 t ADT: 25

481 AVE

Good

Over: CK

3.0E & 4.9S MILBANK, Grant, SD

Built 2005 Load: 32.7 t ADT: 35

153 STREET

Good

Over: CK

3.6E & 4S MILBANK, Grant, SD

Built 2014 Load: 32.7 t ADT: 52

482 AVENUE

Good

Over: SOUTH FORK YELLOW BANK R

0.5S ALBEE, Grant, SD

Built 2017 Load: 32.7 t ADT: 290

482 AVE

Good

Over: SOUTH FORK YELLOW BANK R

0.6S ALBEE, Grant, SD

Built 2017 Load: 32.7 t ADT: 290

483 AVENUE

Good

Over: SOUTH FORK YELLOW BANK R

1E & 0.6S ALBEE, Grant, SD

Built 2017 Load: 32.7 t ADT: 52

483 AVENUE

Good

Over: CK

1E & 1.9S ALBEE, Grant, SD

Built 2012 Load: 32.7 t ADT: 52

484 AVENUE

Good

Over: SOUTH FORK YELLOW BANK R

2E & 0.5S ALBEE, Grant, SD

Built 2012 Load: 32.7 t ADT: 16

484 AVENUE

Good

Over: CK

2E & 1.2S ALBEE, Grant, SD

Built 2015 Load: 32.7 t ADT: 35

Showing 3,801-3,850 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.