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

377TH AVE

Poor

Over: CREEK

1 S 6 W REDFIELD, Spink, SD

Built 1929 Load: 2.9 t ADT: 76

172ND ST

Poor

Over: TURTLE CREEK

1.0E 1.5N REDFIELD, Spink, SD

Built 1915 Load: 2.9 t ADT: 55

277 STREET

Poor

Over: OLD LODGE CK

1N & 1.4E WINNER, Tripp, SD

Built 1950 Load: 2.9 t ADT: 100

375th Avenue

Poor

Over: Willow Creek

3.6S & 10W Barnard, Brown, SD

Built 1968 Load: 3.0 t ADT: 98

421st Avenue

Poor

Over: Antelope Creek

4.8N & 2E of Pierpont, Day, SD

Built 1935 Load: 3.0 t ADT: 10

373 AVE

Poor

Over: WOLF CK

13E & 10.6N MILLER, Hand, SD

Built 1910 Load: 3.0 t ADT: 10

122nd Street

Poor

Over: Creek

1N & 0.1E of Langford, Marshall, SD

Built 1930 Load: 3.0 t ADT: 14

455th Avenue

Poor

Over: Big Sioux River

1.7S of Jct with US 12, Roberts, SD

Built 1939 Load: 3.0 t ADT: 2,500

388TH AVE

Poor

Over: James River

1.9N 2E REDFIELD, Spink, SD

Built 1904 Load: 3.0 t ADT: 35

164TH STREET

Poor

Over: FORDHAM CREEK

8N & 1.6W DOLAND, Spink, SD

Built 1935 Load: 3.0 t ADT: 11

206TH AVENUE

Poor

Over: WHITEWATER CK

4.6S & 4W COTTONWOOD, Jackson, SD

Built 1985 Load: 3.2 t ADT: 15

228 ST

Poor

Over: WEST FORK VERMILLION RV

5N & 0.1E HOWARD, Miner, SD

Built 1930 Load: 3.4 t ADT: 20

TWNSHP RD 187TH ST

Poor

Over: COBB CK

2.3 E & 1 N BRANDT, Deuel, SD

Built 1908 Load: 3.6 t ADT: 25

485 AVENUE

Poor

Over: CK

3E & 4.4S ALBEE, Grant, SD

Built 1948 Load: 3.6 t ADT: 35

231 ST

Poor

Over: EAST FORK VERMILLION RV

2.3N & 1.2E WINFRED, Lake, SD

Built 1930 Load: 3.6 t ADT: 55

464 AVE

Poor

Over: BATTLE CK

2E & 2.2N RUTLAND, Lake, SD

Built 1930 Load: 3.6 t ADT: 15

407 AVE

Poor

Over: PEARL CK

7.6S 2W CAVOUR, Beadle, SD

Built 1911 Load: 3.9 t ADT: 56

411TH AVENUE

Poor

Over: CK

4.7 N & 2 E MITCHELL, Davison, SD

Built 1935 Load: 4.1 t ADT: 40

MAIL RD

Poor

Over: INDIAN CK

2W 5N NISLAND, Butte, SD

Built 1940 Load: 4.5 t ADT: 22

481 AVENUE

Poor

Over: NORTH FORK YELLOW BANK R

3E & 3.1S MILBANK, Grant, SD

Built 1925 Load: 4.5 t ADT: 137

481 AVENUE

Poor

Over: CK

1W & 3.2S ALBEE, Grant, SD

Built 1930 Load: 4.5 t ADT: 40

366 AVE

Poor

Over: WOLF CK

6 E & 8.4 N MILLER, Hand, SD

Built 1915 Load: 4.5 t ADT: 10

45530 273 ST

Poor

Over: EAST FORK VERMILLION RV

2N & 2.3E PARKER, Turner, SD

Built 1910 Load: 4.5 t ADT: 30

271 STREET

Poor

Over: COTTONWOOD CK

0.8E & 1.9N WITTEN, Tripp, SD

Built 1945 Load: 4.9 t ADT: 50

29280 431st Avenue

Poor

Over: James River

7.2N & 1E of Lesterville, Yankton, SD

Built 1959 Load: 4.9 t ADT: 315

227 AVENUE

Poor

Over: FRANKLIN CK

2W & 3.4N KADOKA, Jackson, SD

Built 1940 Load: 5.0 t ADT: 30

234TH STREET

Poor

Over: Trib to Rapid Ck

3.4 N FARMINGDALE, Pennington, SD

Built 1930 Load: 5.0 t ADT: 15

29620 396th Avenue

Poor

Over: Choteau Creek

0.8N & 1.0E of Wagner, Charles Mix, SD

Built 1930 Load: 5.1 t ADT: 48

42480 302nd Street

Poor

Over: Beaver Creek

4N & 2.1W of Tabor, Bon Homme, SD

Built 1925 Load: 5.2 t ADT: 60

294th Street

Poor

Over: Garden Ck

1.5W & 2.9S Lake Andes, Charles Mix, SD

Built 1940 Load: 5.3 t ADT: 20

IDLEHURST LANE

Poor

Over: RAPID CK

0.8SW CANYON LK DAM - RC, Pennington, SD

Built 1972 Load: 5.3 t ADT: 25

39740 296th Street

Poor

Over: Creek

1.0N & 2.4E of Wagner, Charles Mix, SD

Built 1912 Load: 5.4 t ADT: 48

172 STREET

Poor

Over: CK

3.6E 1.0N HENRY, Codington, SD

Built 1940 Load: 5.4 t ADT: 73

454 AVENUE

Poor

Over: Indian River

10.7W & 4.3S MARVIN, Grant, SD

Built 1936 Load: 5.4 t ADT: 20

475th Avenue

Poor

Over: N. Fork Whetstone Rv

3E & 0.2N of Corona, Roberts, SD

Built 1967 Load: 5.4 t ADT: 25

405th Avenue

Poor

Over: Creek

3.3S & 1W of Groton, Brown, SD

Built 1935 Load: 5.5 t ADT: 98

113th Street

Poor

Over: Spain Ditch

0.5N & 2.1E of Amherst, Marshall, SD

Built 1935 Load: 5.5 t ADT: 35

427th Avenue

Poor

Over: Wild Rice Creek

8.8N & 4E of Britton, Marshall, SD

Built 1960 Load: 5.8 t ADT: 35

113th Street

Poor

Over: Crow Creek

3S & 3.6W of Britton, Marshall, SD

Built 1935 Load: 6.1 t ADT: 30

221st Street

Poor

Over: Spring Creek

2.2W & 2N of Ward, Moody, SD

Built 1915 Load: 6.1 t ADT: 69

139th Street

Poor

Over: Creek

2.8S & 1W of Wilmot, Roberts, SD

Built 1968 Load: 6.1 t ADT: 5

155TH ST

Poor

Over: SNAKE CREEK

1.0S 1.8W NORTHVILLE, Spink, SD

Built 1930 Load: 6.1 t ADT: 31

382ND AVE

Poor

Over: CREEK

1.5S 1.0W NORTHVILLE, Spink, SD

Built 1912 Load: 6.1 t ADT: 55

265 ST

Poor

Over: PLATTE CK

13S 1.1W WHITE LAKE, Aurora, SD

Built 1967 Load: 6.2 t ADT: 66

217th Street

Poor

Over: Creek

9.7W & 12S of Wolsey, Beadle, SD

Built 1930 Load: 6.2 t ADT: 56

29600 426th Avenue

Poor

Over: Prairie Creek

3S & 2E of Scotland, Bon Homme, SD

Built 1905 Load: 6.2 t ADT: 60

TOWN STREET

Poor

Over: REDSTONE CK

CITY PARK - CARTHAGE, Miner, SD

Built 1955 Load: 6.3 t ADT: 30

137TH Street

Poor

Over: Creek

3.2 W & 1 S of Andover, Day, SD

Built 1926 Load: 6.4 t ADT: 115

485 AVENUE

Poor

Over: CK

3E & 4.9S ALBEE, Grant, SD

Built 1955 Load: 6.4 t ADT: 52

318th Avenue

Poor

Over: Creek

3E & 6.5N of Kennebec, Lyman, SD

Built 1930 Load: 6.4 t ADT: 24

Showing 4,951-5,000 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.