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

466TH AVENUE

Good

Over: CK

0.5 S JCT SD 42, Minnehaha, SD

Built 2009 Load: 74.8 t ADT: 2,579

SD044

Good

Over: CASTALIA CK

4.9 W OF PLATTE, Charles Mix, SD

Built 1963 Load: 75.1 t ADT: 1,437

I229 S

Good

Over: BIG SIOUX RV

0.2 SW WESTERN AV INTERCH, Minnehaha, SD

Built 1994 Load: 75.3 t ADT: 20,465

I229 N

Good

Over: BIG SIOUX RV

0.2 SW WESTERN AV INTERCH, Minnehaha, SD

Built 1995 Load: 75.3 t ADT: 20,465

SD042

Good

Over: ELCE CK

0.8 W JCT SD 19 S, Minnehaha, SD

Built 1995 Load: 75.9 t ADT: 2,440

SD050

Good

Over: CK

11.6 N JCT SD44, Charles Mix, SD

Built 1984 Load: 76.1 t ADT: 156

NORWEFIAN AVE.

Good

Over: NORWEFIAN GULCH

6.3S & 7.5E IRENE, Clay, SD

Built 1996 Load: 76.3 t ADT: 25

SD037

Good

Over: PONY CK

0.2 N JCT SD 44, Hutchinson, SD

Built 1992 Load: 76.3 t ADT: 3,928

SD020

Good

Over: CK

0.2 E OF PRARIE CITY, Perkins, SD

Built 2008 Load: 76.6 t ADT: 424

LIBERTY BLVD

Good

Over: EAST TRIB BOX ELDER CK

0.3 MI S. I-90 EXIT 67, Pennington, SD

Built 2002 Load: 76.7 t ADT: 2,785

Hilland Road

Good

Over: ASH CK

13.2 W 19.5 N PHILIP, Haakon, SD

Built 1983 Load: 76.9 t ADT: 28

IRR SD034

Good

Over: DRAW

4.8MI W JCT SD47, Hyde, SD

Built 2001 Load: 77.3 t ADT: 575

US083

Good

Over: LITTLE CHEYENNE CK

8.8 S WALWORTH CO LINE, Potter, SD

Built 2003 Load: 77.6 t ADT: 939

455th Avenue

Good

Over: Long Hollow

3W & 1.7N of Sisseton, Roberts, SD

Built 2004 Load: 77.8 t ADT: 505

347TH AVE

Good

Over: CK

2W & 1.7N REE HEIGHTS, Hand, SD

Built 2008 Load: 78.4 t ADT: 15

SD251

Good

Over: MASDON CK

5.1 S JCT US 18, Gregory, SD

Built 1996 Load: 79.0 t ADT: 405

SD052

Good

Over: CK

4.5 W OF YANKTON, Yankton, SD

Built 1988 Load: 79.4 t ADT: 6,425

I090

Good

Over: CK

1.7 W OF DAVISON CO LINE, Aurora, SD

Built 1965 Load: 79.5 t ADT: 9,890

418th Avenue

Good

Over: Creek

3.0E & 8.2N of Carpenter, Clark, SD

Built 2018 Load: 79.5 t ADT: 39

SD011

Good

Over: EAST BRULE CK

2.2 S JCT SD 46, Union, SD

Built 1965 Load: 79.6 t ADT: 1,169

SD045

Good

Over: CK

1.9 S I 90 INTERCH, Brule, SD

Built 1948 Load: 79.9 t ADT: 963

39480 289 ST

Good

Over: CHOTEAU CK

8.ON,0.2W OF WAGNER, Charles Mix, SD

Built 2009 Load: 80.3 t ADT: 48

US016A

Good

Over: GRACE COOLIDGE CK

5.7 E JCT SD 87 N, Custer, SD

Built 1987 Load: 80.4 t ADT: 1,335

QUINN RD

Good

Over: UNNAMED CK

0.7 N QUINN, Pennington, SD

Built 1990 Load: 80.5 t ADT: 100

SD1804

Good

Over: SPRING CK

1.1 S SULLY CO LINE, Hughes, SD

Built 2007 Load: 80.9 t ADT: 1,286

30020 458 AVE.

Good

Over: SPRING CK

3.2S & 6E IRENE, Clay, SD

Built 2009 Load: 81.0 t ADT: 25

SD044

Good

Over: CK

19 SE OF SCENIC, Pennington, SD

Built 1983 Load: 81.8 t ADT: 486

466TH AVENUE

Good

Over: CK

0.4 N LINCOLN CO LINE, Minnehaha, SD

Built 2009 Load: 82.5 t ADT: 2,787

455 AVENUE

Good

Over: SOO CK

1.1 N JCT SD 20 E, Codington, SD

Built 1999 Load: 82.6 t ADT: 1,460

IRR SD020

Good

Over: CK

8.3 W OF TRAIL CITY, Corson, SD

Built 2000 Load: 84.3 t ADT: 1,031

US016A

Good

Over: IRON CK

3.8 S PENNINGTON CO LINE, Custer, SD

Built 1992 Load: 84.3 t ADT: 534

US014

Good

Over: MEDICINE CK

9.3 E OF PHILIP, Haakon, SD

Built 1994 Load: 84.5 t ADT: 725

SD046

Good

Over: MUD CK

1.6 E JCT US 81, Yankton, SD

Built 2022 Load: 84.5 t ADT: 1,526

IRR US012

Good

Over: CK

2.0 W JCT SD 63, Corson, SD

Built 1991 Load: 84.6 t ADT: 402

SD053

Good

Over: WILLIAMS CK

0.8MI N MELLETTE CO LINE, Lyman, SD

Built 2001 Load: 85.8 t ADT: 60

35320 270 STREET

Good

Over: SNAKE CK

1.0N,1.8W OF ACADEMY, Charles Mix, SD

Built 2003 Load: 86.2 t ADT: 175

45860 300TH ST

Good

Over: SPRING CK

3S & 6.6E IRENE, Clay, SD

Built 2004 Load: 86.2 t ADT: 70

US083

Good

Over: CK

2.5 S OF HERREID, Campbell, SD

Built 2006 Load: 86.3 t ADT: 1,071

I090 EF

Good

Over: CK

SUMMERSET, Meade, SD

Built 2008 Load: 86.9 t ADT: 1,860

SD020

Good

Over: CK

0.9 E OF PRAIRIE CITY, Perkins, SD

Built 2008 Load: 87.2 t ADT: 424

US014A

Good

Over: CK

0.7 W I 90 INTERCH, Lawrence, SD

Built 1994 Load: 87.4 t ADT: 8,773

SD020

Good

Over: SQUAW CK

12.0 E JCT US 85, Harding, SD

Built 1994 Load: 88.4 t ADT: 158

345 AVENUE

Good

Over: SOUTH FORK WHETSTONE CK

1.5E & 5.4N BURKE, Gregory, SD

Built 2001 Load: 89.0 t ADT: 560

216TH STREET

Good

Over: CK

4S BROOKINGS, Brookings, SD

Built 2010 Load: 89.8 t ADT: 1,326

217TH STREET

Good

Over: CK

5S & 1.3W BROOKINGS, Brookings, SD

Built 1966 Load: 89.8 t ADT: 92

213TH STREET

Good

Over: CK

1N & 1.9W AURORA, Brookings, SD

Built 2007 Load: 89.8 t ADT: 50

197 ST

Good

Over: SIX MILE CK

6.5N & O.2E WHITE, Brookings, SD

Built 2006 Load: 89.8 t ADT: 92

486TH AVENUE

Good

Over: TRIB TO MEDARY CK

8.0E & 0.5N BUSHNELL, Brookings, SD

Built 2005 Load: 89.8 t ADT: 175

DOUBLE R RD

Good

Over: NORTH FORK SULPHUR CK

12 E 14.4 N NEWELL, Butte, SD

Built 2004 Load: 89.8 t ADT: 35

22730 363rd Avenue

Good

Over: Trib. to Platte Creek

1.3S & 4.0W of Platte, Charles Mix, SD

Built 2018 Load: 89.8 t ADT: 48

Showing 4,751-4,800 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.