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

SD019

Good

Over: VERMILLION RV

0.1 S JCT SD 46, Clay, SD

Built 2004 Load: 43.6 t ADT: 830

ANAMOSA STREET

Good

Over: RCP&E RR

0.5 S 0.4 E I90 EXIT 59, Pennington, SD

Built 2012 Load: 43.6 t

SD073

Good

Over: FLAT CK

1 N OF SHADEHILL, Perkins, SD

Built 1995 Load: 43.7 t ADT: 705

152 STREET

Good

Over: CK

4S & 0.4W HOVEN, Potter, SD

Built 1991 Load: 43.7 t ADT: 15

451st Avenue

Good

Over: Little Minnesota River

4W & 1N of Claire City, Roberts, SD

Built 2004 Load: 43.7 t ADT: 80

SD036

Good

Over: BEAR CK

2.7 E JCT US 16A, Custer, SD

Built 1991 Load: 43.8 t ADT: 730

I090 W

Good

Over: SKUNK CK

0.8 E SD 38 INTERCH, Minnehaha, SD

Built 2007 Load: 43.8 t ADT: 8,550

SD034

Good

Over: SQUAW CK

4.5 SW JCT SD 13 N, Moody, SD

Built 1986 Load: 43.8 t ADT: 1,942

SD079

Good

Over: BATTLE CK

1.6 S PENNINGTON CO LINE, Custer, SD

Built 1997 Load: 43.9 t ADT: 6,593

US085 N

Good

Over: REDWATER RV

BUTTE CO LINE, Lawrence, SD

Built 2005 Load: 43.9 t ADT: 4,417

SD038

Good

Over: WILLOW CK

2.8 W I 29 INTERCH, Minnehaha, SD

Built 1949 Load: 43.9 t ADT: 4,563

US385 NF

Good

Over: SPRING CK

0.8 NE JCT US 16 E, Pennington, SD

Built 1996 Load: 43.9 t ADT: 5

350TH AVE

Good

Over: SOUTH FORK SNAKE CK

3W FAULKTON, Faulk, SD

Built 1988 Load: 44.0 t ADT: 15

255th Street

Good

Over: W. Fork of Vermillion Rv

2S & 0.9W of Salem, McCook, SD

Built 2019 Load: 44.0 t ADT: 45

GARFIELD AVENUE

Good

Over: BIG SIOUX RIVER

GARFIELD AVE-DELL RAPIDS, Minnehaha, SD

Built 2014 Load: 44.0 t ADT: 1,400

FDR 345

Good

Over: IRON CREEK

T 2 S R 6 E SEC 31, Custer, SD

Built 1956 Load: 44.1 t ADT: 25

180th Street

Good

Over: Trib. to Stray Horse Crk

3.2E & 3N of Castlewood, Hamlin, SD

Built 2019 Load: 44.1 t ADT: 118

180th Street

Good

Over: Trib. to Stray Horse Crk

3N & 7.1E of Castlewood, Hamlin, SD

Built 2020 Load: 44.1 t ADT: 40

GREEN VALLEY RD

Good

Over: CK

4.5S & 1.3W REE HEIGHTS, Hand, SD

Built 2008 Load: 44.1 t ADT: 35

SD248

Good

Over: CK

0.1 E JCT US 183, Lyman, SD

Built 2018 Load: 44.1 t ADT: 219

BOGUS JIM T-370

Good

Over: JIM CREEK

T 2 N R 5 E SEC 10, Meade, SD

Built 1973 Load: 44.1 t ADT: 50

US016 B (SE CONN)

Good

Over: RAPID CK

0.7 SW JCT US16B & SD44, Pennington, SD

Built 2002 Load: 44.1 t ADT: 11,086

467th Avenue

Good

Over: Drainage Ditch

.6W&.6S of Browns Valley, Roberts, SD

Built 2012 Load: 44.1 t ADT: 480

SD271

Good

Over: SPRING CK

0.2 S OF ARTAS, Campbell, SD

Built 1994 Load: 44.2 t ADT: 102

SD079

Good

Over: BEAR BUTTE CK

1.2 N JCT SD 34, Meade, SD

Built 1975 Load: 44.2 t ADT: 2,199

US014

Good

Over: CK

0.4 W OF BLUNT, Hughes, SD

Built 1985 Load: 44.3 t ADT: 2,024

FDR 345

Good

Over: IRON CREEK

T 2 S R 6 E SEC 31, Custer, SD

Built 1954 Load: 44.4 t ADT: 25

SD034 W

Good

Over: PARK CK

0.4 NW JCT SD 19, Lake, SD

Built 1977 Load: 44.4 t ADT: 3,770

MEDARY AVENUE

Good

Over: SIX MILE CK

MEDARY AVE N BYPASS BRKGS, Brookings, SD

Built 1987 Load: 44.5 t ADT: 3,213

SD019

Good

Over: VERMILLION RV OVERFLOW

6.2 S JCT SD 46, Clay, SD

Built 2004 Load: 44.5 t ADT: 830

SD019

Good

Over: VERMILLION RV OVERFLOW

8.9 S JCT SD 46, Clay, SD

Built 2004 Load: 44.5 t ADT: 830

126TH STREET

Good

Over: Antelope Creek

4 N & 5.7 W of Pierpont, Day, SD

Built 2021 Load: 44.5 t ADT: 13

477th Avenue

Good

Over: S Fork of Beaver Creek

3W & 1.2S of Canton, Lincoln, SD

Built 2019 Load: 44.5 t ADT: 75

I090 E

Good

Over: DAKOTA & IOWA RR

0.8 W SD 115 INTERCH, Minnehaha, SD

Built 1993 Load: 44.5 t ADT: 13,405

SHARPE ROAD

Good

Over: BOXELDER CK

5.4E&2S NEWUNDERWOOD, Pennington, SD

Built 2017 Load: 44.5 t ADT: 21

304 AVENUE

Good

Over: COTTONWOOD CK

2.9N WITTEN, Tripp, SD

Built 2023 Load: 44.5 t ADT: 33

SD034

Good

Over: CK

2.1 E SANBORN CO LINE, Miner, SD

Built 2023 Load: 44.6 t ADT: 1,092

31880 472 AVE

Good

Over: BIG DITCH CK

4.0W & 5.2N ELK POINT, Union, SD

Built 2006 Load: 44.6 t ADT: 105

SD050

Good

Over: CHARLEY CK

0.8 N JCT SD 52 W, Bon Homme, SD

Built 1979 Load: 44.7 t ADT: 2,390

IRR BIA RTE 7

Good

Over: BUFFALO SKIN CREEK

15.8 KM NORTH OF US-212, Dewey, SD

Built 2013 Load: 44.7 t ADT: 77

US014A

Good

Over: BEAR BUTTE CK

2.9 W I 90 INTERCH, Lawrence, SD

Built 1975 Load: 44.7 t ADT: 6,096

NEW UNDERWOOD RD.

Good

Over: WEST ELM CK

5 E OF HEREFORD, Meade, SD

Built 1975 Load: 44.7 t ADT: 233

IRR SD127

Good

Over: CK

5.6 E JCT SD 106, Roberts, SD

Built 2023 Load: 44.7 t ADT: 669

314th Street

Good

Over: Emanuel Creek

2SW of Springfield, Bon Homme, SD

Built 1997 Load: 44.8 t ADT: 610

SD046

Good

Over: ASH CK

2.6 W I 29 INTERCH, Lincoln, SD

Built 2020 Load: 44.8 t ADT: 2,694

SD034

Good

Over: FOUR MILE CK

19.5 NE JCT SD 79 N, Meade, SD

Built 2015 Load: 44.8 t ADT: 847

SD075

Good

Over: THUNDER BUTTE CK

0.2 N JCT SD 20, Perkins, SD

Built 1994 Load: 44.8 t ADT: 205

IRR SD034

Good

Over: CK

2.1 E JCT SD 50, Buffalo, SD

Built 1999 Load: 44.9 t ADT: 468

INDIAN CANYON

Good

Over: PLUM CK

8.7E JCT SD 471, Fall River, SD

Built 1982 Load: 44.9 t ADT: 77

203RD STREET

Good

Over: BIG SIOUX RV

0.25N & 0.4W BRUCE, Brookings, SD

Built 1994 Load: 45.0 t ADT: 92

Showing 4,351-4,400 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.