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

US212

Good

Over: SOUTH CANAL

1.3 W OF NISLAND, Butte, SD

Built 2002 Load: 99.9 t ADT: 1,740

SD045

Good

Over: CK

4.2 N OF PLATTE, Charles Mix, SD

Built 1998 Load: 99.9 t ADT: 1,270

IRR US018

Good

Over: TRIB TO LAKE ANDES

1.0 E JCT SD 50 W, Charles Mix, SD

Built 2005 Load: 99.9 t ADT: 1,330

302 ST.

Good

Over: CK

2.1E WAKONDA, Clay, SD

Built 1947 Load: 99.9 t ADT: 145

Twin Butte Road

Good

Over: Grand River

9E & 18S THUNDER HAWK, Corson, SD

Built 1990 Load: 99.9 t ADT: 20

237TH AVENUE

Good

Over: FIRESTEEL CREEK

3E & 6.7N ISABEL, Corson, SD

Built 2007 Load: 99.9 t ADT: 30

WEST BULLHEAD ROAD

Good

Over: WHITE SHIRT CREEK

2.4E & 9.7S MCINTOSH, Corson, SD

Built 2016 Load: 99.9 t ADT: 30

SPRING PLACE RD

Good

Over: FRENCH CK

2.2 E & 0.4 N OF CUSTER, Custer, SD

Built 2011 Load: 99.9 t ADT: 50

US016A

Good

Over: GRACE COOLIDGE CK

4.2 E JCT SD 87 N, Custer, SD

Built 1988 Load: 99.9 t ADT: 1,335

SD036

Good

Over: GRACE COOLIDGE CK

0.3 E JCT US 16A, Custer, SD

Built 1989 Load: 99.9 t ADT: 730

SD038

Good

Over: CK

0.7 E JCT SD 37 S, Davison, SD

Built 1988 Load: 99.9 t ADT: 2,719

IRR SD020

Good

Over: LITTLE MOREAU RV

0.1 W JCT SD 63, Dewey, SD

Built 1993 Load: 99.9 t ADT: 598

SD045

Good

Over: CK

0.2 S MCPHERSON CO LINE, Edmunds, SD

Built 1992 Load: 99.9 t ADT: 352

SD045

Good

Over: CK

0.7 N JCT US 12, Edmunds, SD

Built 1992 Load: 99.9 t ADT: 352

142nd Street

Good

Over: Preacher's Run Creek

8S & 9.8E of Ipswich, Edmunds, SD

Built 2009 Load: 99.9 t ADT: 196

SD471

Good

Over: CK

1.8 NW JCT SD 71, Fall River, SD

Built 1991 Load: 99.9 t ADT: 84

SD071

Good

Over: HORSE CK

3.5 N JCT SD 471, Fall River, SD

Built 2000 Load: 99.9 t ADT: 239

RANDALL ROAD

Good

Over: RANDALL CK

3.5S & 18.2E BONESTEEL, Gregory, SD

Built 2003 Load: 99.9 t ADT: 65

464th Avenue

Good

Over: Hidewood Creek

2.5N & 1W of Estelline, Hamlin, SD

Built 2009 Load: 99.9 t ADT: 66

SD034

Good

Over: CK

19.4 E JCT US 14 & 83, Hughes, SD

Built 2015 Load: 99.9 t ADT: 658

277 ST

Good

Over: TRIB DRY CK

6.5E & 1S Parktson, Hutchinson, SD

Built 2013 Load: 99.9 t ADT: 23

42990 284TH ST

Good

Over: Furlong Creek

2.0N,1.1W OF MENNO, Hutchinson, SD

Built 2000 Load: 99.9 t ADT: 10

28010 432 AVE.

Good

Over: CK

5.9N,1.0E OF MENNO, Hutchinson, SD

Built 2022 Load: 99.9 t ADT: 25

IRR SD034

Good

Over: WEST FORK ELM CK

1.4 W JCT SD 47 N, Hyde, SD

Built 2001 Load: 99.9 t ADT: 575

212 STREET

Good

Over: CK

4N STEPHAN, Hyde, SD

Built 2008 Load: 99.9 t ADT: 65

WETA ROAD

Good

Over: FIFTEEN CK

7.7S 7W OF KADOKA, Jackson, SD

Built 1995 Load: 99.9 t ADT: 50

366 AVENUE

Good

Over: CK

1S & 15W WESSNGTN SPRINGS, Jerauld, SD

Built 2017 Load: 99.9 t ADT: 65

368 AVENUE

Good

Over: CK

13W WESSINGTON SPRINGS, Jerauld, SD

Built 2015 Load: 99.9 t ADT: 57

386 AVENUE

Good

Over: CK

3.5W 4.7S LANE, Jerauld, SD

Built 2016 Load: 99.9 t ADT: 42

US014A

Good

Over: CK

2.0 W & S I 90 INTERCH, Lawrence, SD

Built 1994 Load: 99.9 t ADT: 1,854

US014A

Good

Over: CK

1.2 W I 90 INTERCH, Lawrence, SD

Built 1994 Load: 99.9 t ADT: 9,004

US385

Good

Over: BEAR BUTTE CK

6.2 S OF PLUMA, Lawrence, SD

Built 2002 Load: 99.9 t ADT: 2,566

US385

Good

Over: MIDDLE BOX ELDER CK

5.8 N PENNINGTON CO LINE, Lawrence, SD

Built 1995 Load: 99.9 t ADT: 2,250

US014A

Good

Over: DRAW

4.2 SW JCT 90/14A, Lawrence, SD

Built 1999 Load: 99.9 t ADT: 6,096

I029

Good

Over: CK

0.7 S US 18 W INTERCH, Lincoln, SD

Built 1960 Load: 99.9 t ADT: 17,510

I029

Good

Over: HARAM CK

5.2 S US 18 W INTERCH, Lincoln, SD

Built 1960 Load: 99.9 t ADT: 14,270

I029

Good

Over: CK

1.2 N SD 46 INTERCH, Lincoln, SD

Built 1960 Load: 99.9 t ADT: 13,790

Western Avenue

Good

Over: Creek

0.4S of 57th Street, Lincoln, SD

Built 2004 Load: 99.9 t ADT: 6,300

279th Street

Good

Over: Trib Beaver Ck

2.8W & 3N Canton, Lincoln, SD

Built 2021 Load: 99.9 t ADT: 150

SD011

Good

Over: BEAVER CK TRIBUTARY

0.3 S JCT US18, Lincoln, SD

Built 2005 Load: 99.9 t ADT: 1,421

SD011

Good

Over: SOUTH FORK BEAVER CK

1.5 S JCT US 18, Lincoln, SD

Built 2005 Load: 99.9 t ADT: 1,421

481st Avenue

Good

Over: Little Beaver Creak

2.3S of Canton, Lincoln, SD

Built 2017 Load: 99.9 t ADT: 420

320th Street

Good

Over: Medicine Creek

7.8N & 5.9E of Kennebec, Lyman, SD

Built 2017 Load: 99.9 t ADT: 10

415th Avenue

Good

Over: Crow Creek Ditch

2.1N of Amherst, Marshall, SD

Built 2019 Load: 99.9 t ADT: 322

120th Street

Good

Over: Langford Ditch

1W & 3N of Langford, Marshall, SD

Built 2017 Load: 99.9 t ADT: 25

420th Avenue

Good

Over: Creek

3.2N & 1E LANGFORD, Marshall, SD

Built 2014 Load: 99.9 t ADT: 35

SD042

Good

Over: CK

0.9E JCT US 81, McCook, SD

Built 1998 Load: 99.9 t ADT: 1,590

252nd Street

Good

Over: E. Fork Vermillion Rvr

0.5N & 9.9E of Salem, McCook, SD

Built 2015 Load: 99.9 t ADT: 45

SD038

Good

Over: CK

0.1 W MONTROSE B INT, McCook, SD

Built 1947 Load: 99.9 t ADT: 1,104

324th Avenue

Good

Over: Spring Creek

3.5W & 7.3N of Eureka, McPherson, SD

Built 2017 Load: 99.9 t ADT: 21

Showing 4,851-4,900 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.