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

116th Street

Good

Over: Elm River

2.0S & 3.5W of Barnard, Brown, SD

Built 2006 Load: 42.5 t ADT: 10

411TH AVENUE

Good

Over: ENEMY CK

4.1S 2.0E MITCHELL, Davison, SD

Built 2021 Load: 42.5 t ADT: 64

2nd Avenue

Good

Over: Trib. to Big Sioux River

2nd Avenue - Castlewood, Hamlin, SD

Built 2014 Load: 42.5 t ADT: 890

US083

Good

Over: ASH CK

1.8 N MELLETTE CO LINE, Jones, SD

Built 2019 Load: 42.5 t ADT: 1,601

SD011

Good

Over: SPRING CK TRIB

1.6 S MINNEHAHA CO LINE, Lincoln, SD

Built 2015 Load: 42.5 t ADT: 4,532

BALL FIELD RD.

Good

Over: CK

3 S & 3.4 E UNION CT, Meade, SD

Built 2018 Load: 42.5 t ADT: 33

BENTON STREET

Good

Over: SKUNK CK

3.2E & 0.5S HARTFORD, Minnehaha, SD

Built 1999 Load: 42.5 t ADT: 127

486TH AVENUE

Good

Over: BEAVER CREEK

1W & 0.7S VALLEY SPRINGS, Minnehaha, SD

Built 1999 Load: 42.5 t ADT: 74

ORMAN ROAD

Good

Over: CK

1 N 4.3 W NEWELL, Butte, SD

Built 2022 Load: 42.6 t ADT: 72

39430 291st Street

Good

Over: Choteau Creek

6.0N & 0.7W of Wagner, Charles Mix, SD

Built 1997 Load: 42.6 t ADT: 48

IRR US212

Good

Over: LITTLE BEAR CK

1.8 E ZIEBACH CO LINE, Dewey, SD

Built 2023 Load: 42.6 t ADT: 1,272

471 AVENUE

Good

Over: SOUTH FORK WHETSTONE RV

0.5 MI N. OF TWIN BROOKS, Grant, SD

Built 2008 Load: 42.6 t ADT: 100

SD020

Good

Over: CLARKS FORK CK

8.8 E JCT US 85, Harding, SD

Built 1995 Load: 42.6 t ADT: 158

US014

Good

Over: NORTH MEDICINE CK

1.4 NE OF BLUNT, Hughes, SD

Built 1985 Load: 42.6 t ADT: 1,933

ST ONGE ROAD

Good

Over: FALSE BOTTOM CK

2.6 S ST. ONGE, Lawrence, SD

Built 2023 Load: 42.6 t ADT: 600

145TH AVE.

Good

Over: BEAR BUTTE CK

7 E 3 N BEAR BUTTE, Meade, SD

Built 2017 Load: 42.6 t ADT: 15

SD258

Good

Over: SNOW CK

0.5N & E I90 INTERCHANGE, Aurora, SD

Built 1950 Load: 42.7 t ADT: 807

SD034

Good

Over: CROW CK

0.7 W JCT SD 45, Buffalo, SD

Built 1987 Load: 42.7 t ADT: 468

SD042

Good

Over: EAST FORK VERMILLION RV

1.9 W MINNEHAHA CO LINE, McCook, SD

Built 1984 Load: 42.7 t ADT: 2,440

469th Avenue

Good

Over: Drainage Ditch

0.8S of Browns Valley, MN, Roberts, SD

Built 2012 Load: 42.7 t ADT: 328

FDR 345

Good

Over: IRON CREEK

T 2 S R 5 E SEC 36, Custer, SD

Built 1957 Load: 42.8 t ADT: 25

SD026

Good

Over: SHAEFER CK

2.8 W JCT SD 45, Hand, SD

Built 2019 Load: 42.8 t ADT: 142

IRR SD010

Good

Over: CK

1.5 W JCT SD 127 N, Roberts, SD

Built 2019 Load: 42.8 t ADT: 6,952

230TH STREET

Good

Over: REDSTONE CK

2N & 1.6E FORESTBURG, Sanborn, SD

Built 1992 Load: 42.8 t ADT: 75

ORMAN RD

Good

Over: INDIAN CK

1 N 4.7 W NEWELL, Butte, SD

Built 2021 Load: 42.9 t ADT: 72

241st Street

Good

Over: Pipestone Creek

7.3E & 1S of Trent, Moody, SD

Built 2002 Load: 43.0 t ADT: 45

US281

Good

Over: CK

4.8N & 0.2W CORSICA, Douglas, SD

Built 1998 Load: 43.1 t ADT: 1,294

367TH AVE

Good

Over: LITTLE TURTLE CK

7E & 6.6N MILLER, Hand, SD

Built 1932 Load: 43.1 t ADT: 43

US083

Good

Over: HORSE CK

3.1 N MELLETTE CO LINE, Jones, SD

Built 2019 Load: 43.1 t ADT: 1,375

176 STREET

Good

Over: OKOBOJO CK

4E AGAR, Sully, SD

Built 2023 Load: 43.1 t ADT: 230

I090 W

Good

Over: DAKOTA & IOWA RR

0.8 W SD 115 INTERCH, Minnehaha, SD

Built 1992 Load: 43.2 t ADT: 13,405

27370 461 AVE

Good

Over: LONG CK

3.3N CHANCELLOR, Turner, SD

Built 2004 Load: 43.2 t ADT: 657

SD046

Good

Over: CK

1 N IOWA STATE LINE, Union, SD

Built 1954 Load: 43.2 t ADT: 1,831

SD045

Good

Over: DRAINAGE CHANNEL

0.3 N JCT SD 44, Charles Mix, SD

Built 1994 Load: 43.3 t ADT: 4,706

420th Avenue

Good

Over: Creek

1E & 1.7N of Pierpont, Day, SD

Built 2009 Load: 43.3 t ADT: 25

110th Street

Good

Over: Little Minnesota River

4S & 0.5W of Hammer, Roberts, SD

Built 2014 Load: 43.3 t ADT: 68

SD044

Good

Over: WEST FORK VERMILLION RV

2.9 W JCT SD 19, Turner, SD

Built 1976 Load: 43.3 t ADT: 2,330

I090

Good

Over: TRIB W VERMILLION RV

1.4 E US 81 INTERCH, McCook, SD

Built 2021 Load: 43.4 t ADT: 6,085

US081

Good

Over: JAMES RV

1.7 S JCT SD 46, Yankton, SD

Built 2000 Load: 43.4 t ADT: 3,606

SD052

Good

Over: SNATCH CK

6.0 E JCT SD 37, Bon Homme, SD

Built 2005 Load: 43.5 t ADT: 836

6TH ST

Good

Over: FRENCH CK

6th St S of Washington St, Custer, SD

Built 1994 Load: 43.5 t ADT: 50

7TH ST

Good

Over: FRENCH CK

7th St S of Washington St, Custer, SD

Built 1994 Load: 43.5 t ADT: 50

464 AVE

Good

Over: BUFFALO CK

1.6S CHESTER, Lake, SD

Built 2020 Load: 43.5 t ADT: 883

ST ONGE ROAD

Good

Over: FALSE BOTTOM CK

0.1W 1.3S. ST. ONGE, Lawrence, SD

Built 2023 Load: 43.5 t ADT: 600

255TH ST

Good

Over: SKUNK CK

1.8W & 7S COLTON, Minnehaha, SD

Built 2014 Load: 43.5 t ADT: 13

478TH AVE, HWY 121

Good

Over: SLIP-UP CK

4E & 2.5S BALTIC, Minnehaha, SD

Built 2014 Load: 43.5 t ADT: 1,251

478TH AVE, HWY 121

Good

Over: SLIP-UP CK

4E & 3.5S BALTIC, Minnehaha, SD

Built 2014 Load: 43.5 t ADT: 1,340

SD044

Good

Over: CK

17.7 SE OF SCENIC, Pennington, SD

Built 1983 Load: 43.5 t ADT: 486

US012

Good

Over: BURLINGTON NORTHERN RR

0.2 S JCT SD 130 E, Walworth, SD

Built 1969 Load: 43.5 t ADT: 1,900

SD052

Good

Over: CHARLEY CK

1.2 W JCT SD 50, Bon Homme, SD

Built 2005 Load: 43.6 t ADT: 836

Showing 4,301-4,350 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.