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

COUNTY RD

Good

Over: BOX ELDER CK

3.8E 0.1S BLACK HAWK, Meade, SD

Built 2003 Load: 40.9 t ADT: 1,895

466TH AVENUE

Good

Over: BIG SIOUX RV

1.7N BRUCE, Brookings, SD

Built 2021 Load: 41.0 t ADT: 485

IRR US212

Good

Over: VIRGIN CK

0.6 E OF LAPLANT, Dewey, SD

Built 1988 Load: 41.0 t ADT: 671

230TH STREET

Good

Over: REDSTONE CK

2N & 1.8E FORESTBURG, Sanborn, SD

Built 1992 Load: 41.0 t ADT: 75

469th Avenue

Good

Over: Trib. to Saddle Creek

9.2S & 3E of Lennox, Lincoln, SD

Built 2019 Load: 41.1 t ADT: 135

FDR 140

Good

Over: BOX ELDER CREEK

T 3 N R 5 E SEC 27, Meade, SD

Built 1948 Load: 41.1 t ADT: 50

SD011

Good

Over: SPLIT ROCK CK

1.2 N I 90 INTERCH, Minnehaha, SD

Built 2004 Load: 41.1 t ADT: 3,797

HWY 1416

Good

Over: Trib. to Box Elder Creek

6.7 E. NEW UNDERWOOD, Pennington, SD

Built 2013 Load: 41.1 t ADT: 156

US016A

Good

Over: FRENCH CK

0.8 E JCT SD 89 N, Custer, SD

Built 1964 Load: 41.2 t ADT: 1,691

SKUNK CREEK AVE

Good

Over: SKUNK CK

2.5E & 0.4N HARTFORD, Minnehaha, SD

Built 1988 Load: 41.2 t ADT: 55

264TH STREET

Good

Over: BEAVER CREEK

1.8E & 2.5S BRANDON, Minnehaha, SD

Built 2014 Load: 41.2 t ADT: 32

466TH AVENUE

Good

Over: BIG SIOUX RV

5.8N BRUCE, Brookings, SD

Built 2017 Load: 41.3 t ADT: 390

IRR US018

Good

Over: SAINT FRANCIS BAY

0.8 N OF PICKSTOWN, Charles Mix, SD

Built 2023 Load: 41.3 t ADT: 1,608

30730 452 AVE

Good

Over: CLAY CK DITCH

10.3S IRENE, Clay, SD

Built 2010 Load: 41.3 t ADT: 97

172 STREET

Good

Over: CK

4N & 4.3W OF AGAR, Sully, SD

Built 2023 Load: 41.3 t ADT: 48

PINE HILLS ROAD

Good

Over: COTTONWOOD CK

0.5S EDGEMONT, Fall River, SD

Built 1978 Load: 41.4 t ADT: 10

SD045

Good

Over: PLATTE CK

3.2 N OF PLATTE, Charles Mix, SD

Built 1998 Load: 41.5 t ADT: 1,270

39550 280 ST

Good

Over: CHOTEAU CK

0.5N & 3.5E OF ARMOUR, Douglas, SD

Built 2023 Load: 41.5 t ADT: 407

SD020

Good

Over: CK

2.5 S JCT SD 158, Grant, SD

Built 2021 Load: 41.5 t ADT: 1,368

MAPLETON RD

Good

Over: BIG SIOUX RIVER

1.3W & 0.8N RENNER, Minnehaha, SD

Built 1990 Load: 41.5 t ADT: 59

261ST STREET

Good

Over: SPLIT ROCK CREEK

0.4E & 0.5N BRANDON, Minnehaha, SD

Built 2016 Load: 41.5 t ADT: 398

237th Street

Good

Over: Bachelor Creek

2.0S & 0.1W of Colman, Moody, SD

Built 2005 Load: 41.5 t ADT: 50

US081

Good

Over: BATTLE CK

4.1 S BROOKINGS CO LINE, Lake, SD

Built 1954 Load: 41.6 t ADT: 1,600

SD034

Good

Over: CK

3.7 SE BUTTE CO LINE, Lawrence, SD

Built 1963 Load: 41.6 t ADT: 3,410

248th Street

Good

Over: E. Fork of Vermillion Rv

6.5N & 1.1W of Montrose, McCook, SD

Built 2008 Load: 41.6 t ADT: 120

472A AVENUE

Good

Over: CK

5.5W & 9.1N TORONTO, Deuel, SD

Built 2020 Load: 41.7 t ADT: 19

CO RD 310 488TH AV

Good

Over: MONIGHAN CK

1.9N GARY, Deuel, SD

Built 2000 Load: 41.7 t ADT: 20

478th Avenue

Good

Over: Big Sioux River

9N of Egan, Moody, SD

Built 2022 Load: 41.7 t ADT: 231

305 AVENUE

Good

Over: OKOBOJO CK

1.9S & 0.8E AGAR, Sully, SD

Built 1990 Load: 41.7 t ADT: 80

US083

Good

Over: RIEGER CK

2.9 S JCT US 12, Walworth, SD

Built 2005 Load: 41.7 t ADT: 844

107th Street

Good

Over: Maple River

City of Frederick, Brown, SD

Built 1997 Load: 41.8 t ADT: 250

SD050

Good

Over: NELSON CK

4.6 S I 90 INTERCH, Brule, SD

Built 1970 Load: 41.8 t ADT: 233

I090

Good

Over: RCP&E RR

1.6 NW TILFORD INTERCH, Meade, SD

Built 1981 Load: 41.8 t ADT: 18,420

SD019

Good

Over: WEST FORK VERMILLION RV

0.9 N JCT SD 44 WEST, Turner, SD

Built 1986 Load: 41.8 t ADT: 1,660

US018

Good

Over: TURKEY RIDGE CK

1.7 W JCT SD 19, Turner, SD

Built 2019 Load: 41.8 t ADT: 1,669

43240 Stone Chruch

Good

Over: Trib. to James River

7.6N & 2.3E Lesterville, Yankton, SD

Built 2021 Load: 41.9 t ADT: 100

US083

Good

Over: SPRING CK

1.0 S OF HERREID, Campbell, SD

Built 2006 Load: 42.1 t ADT: 1,071

261st Street

Good

Over: W. Fork of Vermillion Rv

4.1W of Canistota, McCook, SD

Built 2003 Load: 42.1 t ADT: 230

467TH AVENUE

Good

Over: SKUNK CK

2W & 0.2N ELLIS, Minnehaha, SD

Built 2017 Load: 42.1 t ADT: 126

467TH AVENUE

Good

Over: TRIB TO SKUNK CK

3.6S & 2W ELLIS, Minnehaha, SD

Built 2016 Load: 42.1 t ADT: 102

US018

Good

Over: TRIB TURKEY RIDGE CK

3.1 W JCT SD 19, Turner, SD

Built 2018 Load: 42.1 t ADT: 915

116th Street

Good

Over: Willow Creek

2S & 7.1W of Barnard, Brown, SD

Built 1999 Load: 42.3 t ADT: 35

387th Avenue

Good

Over: Maple River

1.8N & 0.7E of Frederick, Brown, SD

Built 2023 Load: 42.3 t ADT: 98

C HY 6/STAMFORD RD

Good

Over: WHITE RV

18.9N & 0.8W CEDAR BUTTE, Mellette, SD

Built 2017 Load: 42.3 t ADT: 85

Southeastern Ave

Good

Over: Drainage Channel

north of 26th Street, Minnehaha, SD

Built 2020 Load: 42.3 t ADT: 5,300

IRR US018

Good

Over: CK

2.3 E OF PINE RIDGE, Oglala Lakota, SD

Built 2016 Load: 42.3 t ADT: 3,755

294th Street

Good

Over: West Brule Creek

3.1E & 2N of Beresford, Lincoln, SD

Built 2023 Load: 42.4 t ADT: 390

263RD ST, HWY 140

Good

Over: SKUNK CK

0.5N & 2.4W ELLIS, Minnehaha, SD

Built 1989 Load: 42.4 t ADT: 1,082

187 ST

Good

Over: FOSTER CREEK

3N & 1.1W BLOOMFIELD, Spink, SD

Built 1990 Load: 42.4 t ADT: 31

US018

Good

Over: TRIB TURKEY RIDGE CK

4.9 E TURKEY RIDGE, Turner, SD

Built 2019 Load: 42.4 t ADT: 875

Showing 4,251-4,300 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.