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

IRR US018

Good

Over: STINKING WATER CK

5.3 NE JCT SD 391, Oglala Lakota, SD

Built 2003 Load: 58.8 t ADT: 1,168

SD036

Good

Over: GRACE COOLIDGE CK

0.6 E JCT US 16A, Custer, SD

Built 1989 Load: 58.9 t ADT: 730

I090 EB OFF RAMP

Good

Over: CHANNEL CK

2.7 W OF BOX ELDER, Pennington, SD

Built 1994 Load: 58.9 t ADT: 4,974

US281

Good

Over: BRANCH OF FIRESTEEL CK

4.3 S JERAULD COUNTY LINE, Aurora, SD

Built 1959 Load: 59.0 t ADT: 1,115

375th Avenue

Good

Over: Cain Creek

1E of Wessington, Beadle, SD

Built 2021 Load: 59.1 t ADT: 56

466TH AVENUE

Good

Over: CK

6.5N BRUCE, Brookings, SD

Built 2017 Load: 59.1 t ADT: 390

SOUTH CONNECTOR

Good

Over: PELICAN LAKE CUTOFF CHAN

0.7E & 0.6S JCT 20/212, Codington, SD

Built 2012 Load: 59.1 t ADT: 100

US083

Good

Over: OKOBOJO CK

3.4 S OF AGAR, Sully, SD

Built 1998 Load: 59.1 t ADT: 1,452

467TH AVENUE

Good

Over: CK

4W & 4.2S BROOKINGS, Brookings, SD

Built 2008 Load: 59.2 t ADT: 92

206TH STREET

Good

Over: CK

6N & 0.1E BROOKINGS, Brookings, SD

Built 2002 Load: 59.4 t ADT: 30

HAZELRODT CUTOFF

Good

Over: FRENCH CK

4.5SE CUSTER, Custer, SD

Built 2017 Load: 59.5 t ADT: 188

I090 W

Good

Over: FALSE BOTTOM CK

1 E US 14A INTERCH, Lawrence, SD

Built 1970 Load: 59.5 t ADT: 8,525

363RD AVE

Good

Over: LITTLE TURTLE CK

6.5N ST LAWRENCE, Hand, SD

Built 2008 Load: 59.7 t ADT: 109

207TH STREET

Good

Over: TRIB TO BIG SIOUX RV

4.0N & 0.5E VOLGA, Brookings, SD

Built 2006 Load: 59.8 t ADT: 67

355 AVE

Good

Over: SQUAW CK

5.0E & 6.9S HERRICK, Gregory, SD

Built 2005 Load: 59.8 t ADT: 12

161ST STR

Good

Over: CK

0.3N & 1.3E STRANDBURG, Grant, SD

Built 2000 Load: 59.9 t ADT: 250

GOLDEN GATE ST.

Good

Over: DEADWOOD CK

CENTRAL CITY, Lawrence, SD

Built 1992 Load: 60.0 t ADT: 50

191ST ST

Good

Over: LITTLE TURTLE CK

6.5E & 6N MILLER, Hand, SD

Built 2002 Load: 60.1 t ADT: 43

SD034

Good

Over: PIPESTONE CK

1.7 W OF MINN STATE LINE, Moody, SD

Built 2010 Load: 60.1 t ADT: 1,552

47380 312TH ST

Good

Over: CK

13.7S & 1.8E BERESFORD, Union, SD

Built 2007 Load: 60.1 t ADT: 25

BIA 10

Good

Over: MEDICINE CREEK

12KM SW OF LOWER BRULE, Lyman, SD

Built 2018 Load: 60.2 t ADT: 338

419 ST

Good

Over: REDSTONE CK

5.9N & 2W FEDORA, Miner, SD

Built 2001 Load: 60.4 t ADT: 40

405 AVE

Good

Over: DRY RUN CK

1.0N LOOMIS, Davison, SD

Built 2005 Load: 60.5 t ADT: 64

SD079

Good

Over: CK

11.9 S JCT SD 36 W, Custer, SD

Built 1956 Load: 60.6 t ADT: 1,836

413 AVE

Good

Over: SOUTH BRANCH DRY CK

4.4S & 3E Parkston, Hutchinson, SD

Built 2006 Load: 60.6 t ADT: 45

45660 284 ST.

Good

Over: CK

0.5S & 0.6E HURLEY, Turner, SD

Built 2014 Load: 60.7 t ADT: 50

US016A

Good

Over: GRACE COOLIDGE CK

4.5 E JCT SD 87 N, Custer, SD

Built 1987 Load: 60.9 t ADT: 1,335

262ND ST, HWY 138

Good

Over: TRIB TO BEAVER CK

0.3W VALLEY SPRINGS, Minnehaha, SD

Built 1988 Load: 60.9 t ADT: 3,139

262 ST

Good

Over: PLATTE CK

10S 2.8W WHITE LAKE, Aurora, SD

Built 1999 Load: 61.4 t ADT: 35

159 ST

Good

Over: SOUTH FORK YELLOW BANK R

2.0N & 3.5E ALBEE, Grant, SD

Built 2005 Load: 61.7 t ADT: 40

459th Avenue

Good

Over: Big Sioux River

1.9S of Castlewood, Hamlin, SD

Built 2018 Load: 61.9 t ADT: 375

227 ST

Good

Over: ROCK CK

4S & 6.3W HOWARD, Miner, SD

Built 2002 Load: 62.0 t ADT: 10

IRR US018

Good

Over: LAKE ANDES OUTLET

0.6 E JCT SD 50 W, Charles Mix, SD

Built 2005 Load: 62.2 t ADT: 1,330

US212

Good

Over: CK

0.4M W JCT.SD47 N, Potter, SD

Built 2001 Load: 62.2 t ADT: 1,035

SD1804

Good

Over: CK

6.0 N JCT CO RD TO ONIDA, Sully, SD

Built 1995 Load: 62.2 t ADT: 262

410th Avenue

Good

Over: Mud Creek

3.1N & 4.0E of Ferney, Brown, SD

Built 2002 Load: 62.6 t ADT: 40

OLD HIGHWAY 18

Good

Over: RED CANYON CK

2.2E EDGEMONT, Fall River, SD

Built 2016 Load: 62.6 t ADT: 50

139th Street

Good

Over: Mud Creek

3.0N & 4.1E of Ferney, Brown, SD

Built 2002 Load: 62.7 t ADT: 10

295th Street

Good

Over: West Brule Creek

2N & 2.3E of Beresford, Lincoln, SD

Built 1996 Load: 62.7 t ADT: 47

SD034

Good

Over: BACHELOR CK

1.4 E LAKE CO LINE, Moody, SD

Built 1993 Load: 62.7 t ADT: 3,239

242 ST

Good

Over: LITTLE VERMILLION RV

3.9E OF CANOVA, Miner, SD

Built 1995 Load: 63.0 t ADT: 200

IRR US018

Good

Over: STINKING WATER CK

5.2 NE JCT SD 391, Oglala Lakota, SD

Built 2003 Load: 63.1 t ADT: 1,168

SD052

Good

Over: CK

2.4 E JCT SD 37, Bon Homme, SD

Built 2021 Load: 63.6 t ADT: 836

US212

Good

Over: CAIN CK

1.1 W JCT SD 15 N, Deuel, SD

Built 2019 Load: 64.2 t ADT: 2,115

SD037

Good

Over: EMANUEL CK

2.7 S JCT US 18, Hutchinson, SD

Built 1984 Load: 64.2 t ADT: 1,862

SD063

Good

Over: DRY CK

0.1 N OF NORRIS, Mellette, SD

Built 1984 Load: 64.2 t

465th Avenue

Good

Over: Trib. to Stray Horse Crk

1.6N & 6E of Castlewood, Hamlin, SD

Built 2020 Load: 64.4 t ADT: 80

213 N LINCOLN AVE

Good

Over: PARK CK

LINCOLN AVE - MADISON, Lake, SD

Built 2003 Load: 64.4 t ADT: 290

463rd Avenue

Good

Over: Trib. to Stray Horse Crk

1.1N & 4.0E of Castlewood, Hamlin, SD

Built 2017 Load: 64.8 t ADT: 125

403RD AVENUE

Good

Over: CK

8 W 3.3 N ETHAN, Davison, SD

Built 2008 Load: 65.0 t ADT: 265

Showing 4,651-4,700 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.