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

OLD BELLE HWY

Good

Over: REDWATER RV

0.5W 7.0N SPEARFISH, Lawrence, SD

Built 2005 Load: 48.7 t ADT: 740

SD042

Good

Over: WEST FORK VERMILLION RV

4.2E JCT US 81, McCook, SD

Built 1998 Load: 48.7 t ADT: 1,590

I090 EF

Good

Over: ELK CK

2.2 N of Exit 44, Meade, SD

Built 2016 Load: 48.7 t ADT: 700

US212

Good

Over: CK

0.5M W JCT. SD47 N, Potter, SD

Built 2001 Load: 48.8 t ADT: 1,035

TOWNSHIP RD

Good

Over: BOXELDER CK

OWANKA, Pennington, SD

Built 2006 Load: 48.9 t ADT: 15

372 AVE

Good

Over: PLATTE CK

11.6S 2W WHITE LAKE, Aurora, SD

Built 2018 Load: 49.0 t ADT: 33

359 AVENUE

Good

Over: WHETSTONE CK

1.5W & 6.3N BONESTEEL, Gregory, SD

Built 2003 Load: 49.0 t ADT: 30

SWANZEY DRIVE

Good

Over: GRIZZLY BEAR CK

150S200E JCT16A40 KEYSTON, Pennington, SD

Built 1974 Load: 49.0 t ADT: 125

SD011

Good

Over: DRAINAGE DITCH

1.9 S JCT SD 50, Union, SD

Built 1983 Load: 49.0 t ADT: 748

IRR BIA RTE 3

Good

Over: VEO CREEK

16 KM EAST OF WHITEHORSE, Dewey, SD

Built 2016 Load: 49.1 t ADT: 550

SD047

Good

Over: SPRING CK

8.2 N JCT SD 10, McPherson, SD

Built 1988 Load: 49.1 t ADT: 70

I029

Good

Over: CK

5.6 N SD 48 INTERCH, Union, SD

Built 1961 Load: 49.2 t ADT: 11,970

30820 471 AVE.

Good

Over: BRULE CK

10.2S BERESFORD, Union, SD

Built 2016 Load: 49.2 t ADT: 400

I090

Good

Over: CK

0.8 W SD 45 S INTERCH, Brule, SD

Built 1964 Load: 49.3 t ADT: 7,670

US081

Good

Over: WEST FORK VERMILLION RV

3.2 S I 90 INTERCH, McCook, SD

Built 1982 Load: 49.3 t ADT: 1,812

SD019

Good

Over: EAST FORK VERMILLION RV

3.7 N JCT SD 44 WEST, Turner, SD

Built 1989 Load: 49.3 t ADT: 1,660

SD040

Good

Over: BATTLE CK

1.5 W OF HERMOSA, Custer, SD

Built 1986 Load: 49.4 t ADT: 980

SD037

Good

Over: NORTH BR DRY CK

1.1 S JCT SD 44, Hutchinson, SD

Built 2000 Load: 49.4 t ADT: 2,294

294th Street

Good

Over: Pattee Creek

1.6W of Hudson, Lincoln, SD

Built 2017 Load: 49.4 t ADT: 372

US016 B (SE CONN)

Good

Over: RCP&E RR

0.3E SD79, Pennington, SD

Built 2005 Load: 49.5 t ADT: 11,086

US016 B (SE CONN)

Good

Over: RCP&E RR

0.2 S I 90 INTERCH, Pennington, SD

Built 2005 Load: 49.5 t ADT: 14,488

SD044

Good

Over: WEST FORK VERMILLION RV

1.3 W JCT SD 19, Turner, SD

Built 1976 Load: 49.5 t ADT: 2,330

484TH AVENUE

Good

Over: CK

2.7N & 2W ELKTON, Brookings, SD

Built 1990 Load: 49.6 t ADT: 92

SD010

Good

Over: Dry Run Creek

5.8 W JCT US 281, Brown, SD

Built 2020 Load: 49.7 t ADT: 725

263RD STREET

Good

Over: NORTH BR TWELVE MILE CK

9 S & 1.1 W MITCHELL, Davison, SD

Built 2001 Load: 49.7 t ADT: 45

SD037 S

Good

Over: DRY RUN CK

4.6 S SANBORN CO LINE, Davison, SD

Built 1975 Load: 49.7 t ADT: 1,596

SD037 N

Good

Over: DRY RUN CK

4.6 S SANBORN CO LINE, Davison, SD

Built 1975 Load: 49.7 t ADT: 1,596

SD020

Good

Over: VALLEY CK

5.0 E MONTANA STATE LINE, Harding, SD

Built 2021 Load: 49.7 t ADT: 132

IRR SD044

Good

Over: CRAVEN CK

0.8 S OF WANBLEE, Jackson, SD

Built 1995 Load: 49.8 t ADT: 553

WHITEWOOD VALLEY

Good

Over: WHITEWOOD CK

0.9N 0.6E WHITEWOOD, Lawrence, SD

Built 2020 Load: 49.9 t ADT: 300

SD044

Good

Over: RAPID CK

5.9 SE JCT US 385, Pennington, SD

Built 1956 Load: 49.9 t ADT: 3,104

US016AEF

Good

Over: GRIZZLY BEAR CK

AT KEYSTONE, Pennington, SD

Built 1973 Load: 50.0 t ADT: 1,993

32015 477TH AVE

Good

Over: CK

3.9N & 1.3E ELK POINT, Union, SD

Built 1997 Load: 50.0 t ADT: 45

104th Street

Good

Over: Wild Rice Creek

0.1S & 3.2E of Kidder, Marshall, SD

Built 2010 Load: 50.2 t ADT: 170

443rd Avenue

Good

Over: Little Vermillion River

4.8N & 2.0E of Salem, McCook, SD

Built 2005 Load: 50.3 t ADT: 45

BRADSKY ROAD

Good

Over: RAPID CK

3.5 W & 1.3 N CAPUTA, Pennington, SD

Built 2018 Load: 50.3 t ADT: 311

250 ST

Good

Over: CK

5.6E 3N PLANKINTON, Aurora, SD

Built 2018 Load: 50.8 t ADT: 60

320 AVENUE

Good

Over: SOUTH MEDICINE CK

0.3W 1.4S HARROLD, Hughes, SD

Built 2022 Load: 51.0 t ADT: 157

SD037 S

Good

Over: JAMES RV

4.6 MILE SOUTH JNCT SD34, Sanborn, SD

Built 2002 Load: 51.0 t ADT: 1,305

250TH ST, HWY 114

Good

Over: WEST PIPESTONE CK

4.1W SHERMAN, Minnehaha, SD

Built 2015 Load: 51.1 t ADT: 906

IRR US018

Good

Over: WHITE CLAY CK

5.6 NW OF PINE RIDGE, Oglala Lakota, SD

Built 2011 Load: 51.2 t ADT: 2,241

397TH AVENUE

Good

Over: Enemy Creek

4.4 S MOUNT VERNON, Davison, SD

Built 2021 Load: 51.3 t ADT: 416

401ST AVENUE

Good

Over: ENEMY CK

7.3 N & 6E MT VERNON, Davison, SD

Built 2003 Load: 51.3 t ADT: 64

408TH AVE

Good

Over: CK

1.4MI S & 1MI W MITCHELL, Davison, SD

Built 2001 Load: 51.3 t ADT: 742

Summit Avenue

Good

Over: Ellis & Eastern Railroad

S of 14th Street - SF, Minnehaha, SD

Built 2004 Load: 51.3 t ADT: 2,472

481ST STREET

Good

Over: MEDARY CK

5E & 0.5N AURORA, Brookings, SD

Built 1999 Load: 51.4 t ADT: 92

SD037

Good

Over: DRY RUN CK

1.2 N I 90 INTERCHANGE, Davison, SD

Built 1996 Load: 51.4 t ADT: 9,143

SD019

Good

Over: CK

1.8 S JCT SD 44 EAST, Turner, SD

Built 1965 Load: 51.4 t ADT: 1,212

IRR SD065

Good

Over: BEAR CK

0.2 N JCT US 212, Ziebach, SD

Built 1984 Load: 51.4 t ADT: 588

SD071

Good

Over: CHEYENNE RV

10 S OF HOT SPRINGS, Fall River, SD

Built 1998 Load: 51.5 t ADT: 239

Showing 4,501-4,550 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.