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

Benson Road

Fair

Over: Trib to Skunk Creek

0.4E of Marion Road, Minnehaha, SD

Built 2013 Load: 60.6 t ADT: 3,800

IRR SD040

Fair

Over: CHEYENNE RV

23 SE HERMOSA, Custer, SD

Built 1994 Load: 60.8 t

280 STREET

Fair

Over: DOG EAR CK

1.2W & 2S WINNER, Tripp, SD

Built 1947 Load: 60.9 t ADT: 49

48060 306 STR.

Fair

Over: EAST UNION CK

4S & 1.6E ALCESTER, Union, SD

Built 1986 Load: 61.0 t ADT: 45

US083

Fair

Over: NORTH FORK MEDICINE CK

2.0 N JCT SD 248, Lyman, SD

Built 2003 Load: 61.1 t ADT: 2,284

SD079

Fair

Over: NORTH FORK WILLOW CK

2.9 S JCT SD 168, Butte, SD

Built 1968 Load: 61.4 t ADT: 660

SD036

Fair

Over: GRACE COOLIDGE CK

0.7 E JCT US 16A, Custer, SD

Built 1989 Load: 61.7 t ADT: 730

SD044

Fair

Over: CK

10.9 E OF WINNER, Tripp, SD

Built 1971 Load: 61.7 t ADT: 568

IRR I029

Fair

Over: BIG SPRING CK

1.2 S PEEVER INTERCH, Roberts, SD

Built 1978 Load: 62.1 t ADT: 5,340

47110 309 STR.

Fair

Over: BRULE CK

11S & 0.1E BERESFORD, Union, SD

Built 1989 Load: 62.1 t ADT: 25

SD047

Fair

Over: CK

5.6 N JCT US 18, Gregory, SD

Built 1957 Load: 62.2 t ADT: 546

SD044

Fair

Over: CK

2.6 SE OF FARMINGDALE, Pennington, SD

Built 1964 Load: 62.5 t ADT: 1,463

US012

Fair

Over: SOUTH FORK WHETSTONE RV

6.8 W JCT SD 15, Grant, SD

Built 1997 Load: 62.6 t ADT: 1,722

US083

Fair

Over: CK

7.7 N JCT SD 248, Lyman, SD

Built 1960 Load: 62.7 t ADT: 2,284

US014 B

Fair

Over: HILGERS GULCH

0.5 E JCT US 14 & 83, Hughes, SD

Built 1969 Load: 63.0 t ADT: 14,036

SD123

Fair

Over: CK

1.9 S ROBERTS CO LINE, Grant, SD

Built 1988 Load: 63.2 t ADT: 276

US183

Fair

Over: DRY RUN CK

1.0 N JCT US 18, Tripp, SD

Built 2001 Load: 63.5 t ADT: 1,075

US281

Fair

Over: BNSF RAILROAD

0.2N JCT US12, Brown, SD

Built 2001 Load: 63.9 t ADT: 4,559

SD044

Fair

Over: ELCE CK

2.1 E JCT SD 19, Turner, SD

Built 1968 Load: 63.9 t ADT: 1,034

US014

Fair

Over: REE CK

0.2 W JCT SD 45, Hand, SD

Built 1987 Load: 64.3 t ADT: 2,243

126th Street

Fair

Over: Foot Creek

7N & 7.2W of Aberdeen, Brown, SD

Built 2007 Load: 64.4 t ADT: 5

I090 W

Fair

Over: BULL CK

3.3 E WASTA INTERCH, Pennington, SD

Built 1964 Load: 64.6 t ADT: 4,000

I090 E

Fair

Over: BULL CK

3.3 E WASTA INTERCH, Pennington, SD

Built 1964 Load: 64.6 t ADT: 4,000

48080 308 STR.

Fair

Over: EAST UNION CK

6.5S & 1.8E ALCESTER, Union, SD

Built 1996 Load: 64.8 t ADT: 35

264th Street

Fair

Over: Wolf Creek

1N & 2.3W of Bridgewater, McCook, SD

Built 1980 Load: 64.9 t ADT: 30

SD040

Fair

Over: BATTLE CK

1.0 E JCT US 16A, Pennington, SD

Built 1974 Load: 65.0 t ADT: 1,110

OFFETT ST

Fair

Over: CK

2.1 E ELK VALE RD - BOX E, Pennington, SD

Built 1963 Load: 65.3 t ADT: 50

SD026

Fair

Over: TURTLE CK OVERFLOW

4.6 W JCT US 281, Spink, SD

Built 1989 Load: 65.4 t ADT: 578

SD027

Fair

Over: ANTELOPE CK

1.2 S MARSHALL CO LINE, Day, SD

Built 1970 Load: 65.8 t ADT: 518

SD038

Fair

Over: JOHNSON CK

6.1 E DAVISON CO LINE, Hanson, SD

Built 1991 Load: 66.2 t ADT: 2,211

SD248

Fair

Over: BR BIG BUFFALO CK

2.1 E OF CACTUS FLATS, Jackson, SD

Built 1956 Load: 66.2 t ADT: 104

SD037

Fair

Over: ENEMY CK

3.6 S I 90 INTERCH, Davison, SD

Built 1946 Load: 66.4 t ADT: 3,929

COUNTY HIGHWAY #11

Fair

Over: CK

9.9N & 3.2E WHITE RV, Mellette, SD

Built 1962 Load: 66.5 t ADT: 40

US014

Fair

Over: JACK DAILY CK

1.6 W OF MIDLAND, Haakon, SD

Built 1981 Load: 67.4 t ADT: 678

I090

Fair

Over: CK

1 E LAWRENCE CO LINE, Meade, SD

Built 1963 Load: 67.5 t ADT: 10,290

SD045

Fair

Over: CK

3.2 S JCT SD 26 E, Hand, SD

Built 2002 Load: 67.8 t ADT: 954

417th Avenue

Fair

Over: Pearl Creek

12.5N & 1W of Iroquois, Beadle, SD

Built 2009 Load: 67.9 t ADT: 56

US212

Fair

Over: DRY RUN CK

7.0 E JCT SD 45 S, Faulk, SD

Built 2008 Load: 68.0 t ADT: 689

31180 476TH AVE

Fair

Over: CK

3E & 1.2N SPINK, Union, SD

Built 1993 Load: 68.7 t ADT: 50

NEMO RD

Fair

Over: BOXELDER CK

10.3W 3.8N RAPID CITY, Pennington, SD

Built 1972 Load: 68.9 t ADT: 974

US385

Fair

Over: FALL RV

0.8 N JCT US 18 W, Fall River, SD

Built 1982 Load: 69.5 t ADT: 4,070

SD045

Fair

Over: LITTLE TURTLE CK

5 N JCT US 14, Hand, SD

Built 2002 Load: 69.9 t ADT: 954

US016

Fair

Over: SPRING CK

2.4 N OF CUSTER CO LINE, Pennington, SD

Built 1996 Load: 70.9 t ADT: 7,034

US014

Fair

Over: BUZZARD CK

13.1 E OF PHILIP, Haakon, SD

Built 1994 Load: 71.1 t ADT: 725

46320 308 ST

Fair

Over: VERMILLION RV OVERFLOW

1.7S & 1.8W OF HUB CITY, Clay, SD

Built 1998 Load: 71.2 t ADT: 25

STATE PARK RD

Fair

Over: RANDALL CK

1.0W & 2.0S PICKSTOWN, Gregory, SD

Built 2020 Load: 71.7 t ADT: 50

US016

Fair

Over: SPRING CK

1.4 N CUSTER CO LINE, Pennington, SD

Built 1998 Load: 71.8 t ADT: 7,034

US016

Fair

Over: SPRING CK

1.3 W JCT US 385, Pennington, SD

Built 1986 Load: 71.9 t ADT: 6,231

SD034

Fair

Over: HAY CK

3.9 W OF UNION CENTER, Meade, SD

Built 1973 Load: 72.0 t ADT: 945

US018

Fair

Over: CK

0.1 W JCT SD 53, Tripp, SD

Built 1965 Load: 72.1 t ADT: 1,053

Showing 2,901-2,950 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.