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

473rd Avenue

Fair

Over: Big Sioux River

8.0W & 8.9N of Flandreau, Moody, SD

Built 1976 Load: 24.5 t ADT: 50

475th Avenue

Fair

Over: Bachelor Creek

5E & 3.7S of Colman, Moody, SD

Built 1979 Load: 24.5 t ADT: 45

244th Street

Fair

Over: Trib. to Big Sioux River

4S & 1.2W of Trent, Moody, SD

Built 1939 Load: 24.5 t ADT: 348

478th Avenue

Fair

Over: Brookfield Creek

0.7S of Trent, Moody, SD

Built 1993 Load: 24.5 t ADT: 45

479th Avenue

Fair

Over: Big Sioux River

1.4S & 8W of Ward, Moody, SD

Built 1978 Load: 24.5 t ADT: 45

237th Street

Fair

Over: Brookfield Creek

3N & 2.8E of Trent, Moody, SD

Built 1956 Load: 24.5 t ADT: 50

483rd Avenue

Fair

Over: Flandreau Creek

2E & 0.4N of Flandreau, Moody, SD

Built 1940 Load: 24.5 t ADT: 350

486th Avenue

Fair

Over: Flandreau Creek

5E & 0.9N of Flandreau, Moody, SD

Built 1956 Load: 24.5 t ADT: 125

236th Street

Fair

Over: Pipestone Creek

9.5E & 4.3N of Trent, Moody, SD

Built 1989 Load: 24.5 t ADT: 69

SHERIDAN LAKE ROAD

Fair

Over: SPRING CK

1.6N3.7W ROCKERVILLE, Pennington, SD

Built 1974 Load: 24.5 t ADT: 933

Copper Hill Drive

Fair

Over: Red Rock Canyon Drainage

50' E Red Rock Canyon Rd, Pennington, SD

Built 2001 Load: 24.5 t ADT: 200

225TH STREET

Fair

Over: BOX ELDER CK

2.7N 1.2W ELK VALE EXIT, Pennington, SD

Built 1990 Load: 24.5 t ADT: 78

DYESS AVE

Fair

Over: BOX ELDER CK

2.3N 1.0W ELK VALE EXIT, Pennington, SD

Built 1990 Load: 24.5 t ADT: 671

RADAR HILL ROAD

Fair

Over: BOXELDER CK

1.0W 0.3S BOX ELDER, Pennington, SD

Built 1989 Load: 24.5 t ADT: 966

E ASH ST

Fair

Over: CK

0.06E S A Ave - New Under, Pennington, SD

Built 1955 Load: 24.5 t ADT: 50

E OAK ST

Fair

Over: CK

0.06E S A Ave - New Under, Pennington, SD

Built 1955 Load: 24.5 t ADT: 50

E PINE ST

Fair

Over: CK

0.07E S A Ave - New Under, Pennington, SD

Built 1955 Load: 24.5 t ADT: 50

197TH AVE

Fair

Over: Trib to Cottonwood Creek

0.2E & 0.8S OF QUINN, Pennington, SD

Built 1935 Load: 24.5 t ADT: 19

PRAIRIE CITY ROAD

Fair

Over: RABBIT CK

17W, 6.9S OF BISON, Perkins, SD

Built 1992 Load: 24.5 t ADT: 91

BIXBY ROAD

Fair

Over: CABIN CK

4.3 W 23.8 S BISON, Perkins, SD

Built 1954 Load: 24.5 t ADT: 89

HAYNES ROAD

Fair

Over: GILES CK

4W 7.8S WHITE BUTTE, Perkins, SD

Built 1948 Load: 24.5 t ADT: 26

HAYNES ROAD

Fair

Over: NORTH FORK GRAND RV

19.7 NORTH OF BISON, Perkins, SD

Built 1996 Load: 24.5 t ADT: 10

FLAT CK ROAD

Fair

Over: FLAT CK

5.5 SOUTH3.3E WHITE BUTTE, Perkins, SD

Built 2008 Load: 24.5 t ADT: 60

COUNTY RD #4

Fair

Over: TRIB TO SHADEHILL CK

11E 5N BISON, Perkins, SD

Built 2004 Load: 24.5 t ADT: 45

299 AVENUE

Fair

Over: CK

11W & 2N GETTYSBURG, Potter, SD

Built 1963 Load: 24.5 t ADT: 15

160 ST

Fair

Over: CK

1.1W LEBANON, Potter, SD

Built 2007 Load: 24.5 t ADT: 45

155 STREET

Fair

Over: CK

7S & 0.3W HOVEN, Potter, SD

Built 1940 Load: 24.5 t ADT: 25

455th Avenue

Fair

Over: Creek

4.8S of Claire City, Roberts, SD

Built 1937 Load: 24.5 t ADT: 412

455th Avenue

Fair

Over: Creek

5.1S of Claire City, Roberts, SD

Built 1937 Load: 24.5 t ADT: 412

455th Avenue

Fair

Over: Creek

6.1S of Claire City, Roberts, SD

Built 1937 Load: 24.5 t ADT: 408

458th Avenue

Fair

Over: Creek

0.1S of Jct with SD 10, Roberts, SD

Built 1941 Load: 24.5 t ADT: 5,850

458th Avenue

Fair

Over: Creek

0.6S of Jct with SD 10, Roberts, SD

Built 1941 Load: 24.5 t ADT: 5,850

459th Avenue

Fair

Over: Creek

9.2S of Jct with SD 10, Roberts, SD

Built 1941 Load: 24.5 t ADT: 1,650

459th Avenue

Fair

Over: Creek

10.2S of Jct with SD 10, Roberts, SD

Built 1941 Load: 24.5 t ADT: 1,600

118th Street

Fair

Over: Creek

1.5E & 1N of Sisseton, Roberts, SD

Built 1983 Load: 24.5 t ADT: 75

460th Avenue

Fair

Over: Creek

7W & 2N of Wilmot, Roberts, SD

Built 1930 Load: 24.5 t ADT: 22

462nd Avenue

Fair

Over: Creek

3.9S of Peever, Roberts, SD

Built 1931 Load: 24.5 t ADT: 271

125th Street

Fair

Over: Jorgenson River

2N & 2E of Peever, Roberts, SD

Built 1981 Load: 24.5 t ADT: 68

127th Street

Fair

Over: Jorgenson River

2.2E of Peever, Roberts, SD

Built 1939 Load: 24.5 t ADT: 198

466th Avenue

Fair

Over: Jim Creek

8E & 2.5N of Sisseton, Roberts, SD

Built 1964 Load: 24.5 t ADT: 15

119th Street

Fair

Over: Jim Creek

9.9E SISSETON, Roberts, SD

Built 1935 Load: 24.5 t ADT: 294

141st Street

Fair

Over: Creek

1.9W & 0.2N of Corona, Roberts, SD

Built 1969 Load: 24.5 t ADT: 68

471st Avenue

Fair

Over: Creek

1W & 0.7N of Corona, Roberts, SD

Built 1984 Load: 24.5 t ADT: 68

140th Street

Fair

Over: N. Fork Whetstone Rv

2.5E & 2N of Corona, Roberts, SD

Built 1973 Load: 24.5 t ADT: 88

101st Street

Fair

Over: Creek

0.7W of White Rock, Roberts, SD

Built 1929 Load: 24.5 t ADT: 144

394th Ave.

Fair

Over: SAND CK

3W & 6.9N WOONSOCKET, Sanborn, SD

Built 1970 Load: 24.5 t ADT: 56

236TH STREET

Fair

Over: MORRIS CK

6S & 0.7W WOONSOCKET, Sanborn, SD

Built 1963 Load: 24.5 t ADT: 183

399TH AVE.

Fair

Over: SAND CK

2E & 7.2N WOONSOCKET, Sanborn, SD

Built 1982 Load: 24.5 t ADT: 56

228TH STREET

Fair

Over: SAND CK

5.1E & 2N WOONSOCKET, Sanborn, SD

Built 1969 Load: 24.5 t ADT: 56

RIVER RD.

Fair

Over: SAND CK

0.2 NE FORESTBURG, Sanborn, SD

Built 1963 Load: 24.5 t ADT: 56

Showing 1,601-1,650 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.