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

199TH STREET

Good

Over: SIX MILE CK

4.5N & 0.5E WHITE, Brookings, SD

Built 1989 Load: 45.0 t ADT: 92

SD071

Good

Over: CK

2.2 N JCT SD 471, Fall River, SD

Built 2000 Load: 45.0 t ADT: 239

US018

Good

Over: TRIB TURKEY RIDGE CK

4.1 E TURKEY RIDGE, Turner, SD

Built 2019 Load: 45.0 t ADT: 875

29620 414th Avenue

Good

Over: Emanuel Creek

6.7N & 2W of Tyndall, Bon Homme, SD

Built 2013 Load: 45.2 t ADT: 60

200TH STREET

Good

Over: BIG SIOUX RV

3N & 1.1E BRUCE, Brookings, SD

Built 2010 Load: 45.2 t ADT: 92

JENNINGS AVENUE

Good

Over: FALL RV

JENNINGS&RIVER HOTSPRNGS, Fall River, SD

Built 2021 Load: 45.2 t ADT: 100

286th Street

Good

Over: Snake Creek

7S & 2.6E of Lennox, Lincoln, SD

Built 2019 Load: 45.2 t ADT: 48

SD042

Good

Over: WEST FORK VERMILLION RV

1.7 E JCT US 81, McCook, SD

Built 1983 Load: 45.3 t ADT: 1,590

US083

Good

Over: WHITE RV

JONES-MELLETTE CO LINE, Mellette, SD

Built 2021 Load: 45.3 t ADT: 1,375

SD053

Good

Over: BUTTE CK

1.8 N JCT SD 44, Mellette, SD

Built 2004 Load: 45.3 t ADT: 106

SD052

Good

Over: UNNAMED CK

7.8 E JCT SD 37, Bon Homme, SD

Built 2021 Load: 45.4 t ADT: 876

OLD HIGHWAY 18

Good

Over: MICKELSON TRAIL

4E & 1.8N EDGEMONT, Fall River, SD

Built 2023 Load: 45.4 t ADT: 50

SD071

Good

Over: CASCADE CK

8 S OF HOT SPRINGS, Fall River, SD

Built 1998 Load: 45.4 t ADT: 383

476 AVENUE

Good

Over: CK

3.3N & 2W MILBANK, Grant, SD

Built 2010 Load: 45.4 t ADT: 20

241 ST

Good

Over: BUFFALO CK

3.1W & 0.2S CHESTER, Lake, SD

Built 2019 Load: 45.4 t ADT: 903

256TH ST, HWY 126

Good

Over: WILLOW CK

1N & 1.7W CROOKS, Minnehaha, SD

Built 2015 Load: 45.4 t ADT: 410

BASE LINE ROAD

Good

Over: BOXELDER CK

1.0 W 3.8 S WASTA, Pennington, SD

Built 2002 Load: 45.4 t ADT: 23

470th Avenue

Good

Over: Creek

2W & 0.1N of Corona, Roberts, SD

Built 1984 Load: 45.4 t ADT: 68

SD020

Good

Over: JAMES RV

5.2 E JCT US 281, Spink, SD

Built 2003 Load: 45.4 t ADT: 953

SD011 SF

Good

Over: WEST UNION CK

4.0 N JCT SD 48, Union, SD

Built 1969 Load: 45.4 t ADT: 50

480TH AVENUE

Good

Over: MEDARY CK

3.4N & 6W ELKTON, Brookings, SD

Built 1989 Load: 45.5 t ADT: 92

MILWAUKEE AVE SE

Good

Over: Moccasin Creek

RAILROAD ST - ABERDEEN, Brown, SD

Built 1986 Load: 45.5 t ADT: 50

223rd Street

Good

Over: Big Sioux River

11W of Ward, Moody, SD

Built 2018 Load: 45.6 t ADT: 250

SD050

Good

Over: BIG SIOUX RIVER

At South Dakota Border, Union, SD

Built 2010 Load: 45.6 t ADT: 1,590

266th Avenue

Good

Over: Bad River

1.4S Stanley Co Line, Jones, SD

Built 1996 Load: 45.7 t ADT: 45

263rd Street

Good

Over: E. Fork of Vermillion Rv

8.5S & 1.1E of Montrose, McCook, SD

Built 2019 Load: 45.7 t ADT: 66

468TH AVENUE

Good

Over: CK

0.9N & 3W BROOKINGS, Brookings, SD

Built 1978 Load: 45.8 t ADT: 92

417th Avenue

Good

Over: Creek

4.2 S & 3.0 E of Raymond, Clark, SD

Built 2022 Load: 45.8 t ADT: 39

SD037 S

Good

Over: SAND CK

3.3 S JCT SD 224, Sanborn, SD

Built 1977 Load: 45.8 t ADT: 1,479

Twin Butte Road

Good

Over: Trib. to Blk Horse Butte

1.0W & 28.5S KELDRON, Corson, SD

Built 2005 Load: 45.9 t ADT: 14

SD251

Good

Over: PONCA CK

2.6 S JST US 18, Gregory, SD

Built 1984 Load: 45.9 t ADT: 405

IRR SD010

Good

Over: CLEAR LAKE INLET

3 SE JCT SD 25 N, Marshall, SD

Built 1993 Load: 45.9 t ADT: 714

SD079

Good

Over: DRY CK

6.6 N FALL RIVER CO LINE, Custer, SD

Built 2004 Load: 46.0 t ADT: 3,672

FDR 345

Good

Over: IRON CREEK

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

Built 1954 Load: 46.0 t ADT: 25

107th Street

Good

Over: Elm River

0.3 N 9.4 W of FREDERICK, Brown, SD

Built 2015 Load: 46.1 t ADT: 77

476th Avenue

Good

Over: Beaver Creek

0.3N & 4E of Worthing, Lincoln, SD

Built 1998 Load: 46.1 t ADT: 65

324 AVENUE

Good

Over: CHAPELLE CK

3.0E & 9.2S HARROLD, Hughes, SD

Built 2022 Load: 46.2 t ADT: 33

254TH ST, HWY 122

Good

Over: WEST BR SKUNK CK

5N & 1.8W HARTFORD, Minnehaha, SD

Built 2020 Load: 46.2 t ADT: 490

SD042

Good

Over: CK

1.9 E JCT SD 17 S, Minnehaha, SD

Built 1989 Load: 46.2 t ADT: 6,982

60th Street North

Good

Over: Creek

West of I-29 - SF, Minnehaha, SD

Built 1996 Load: 46.2 t ADT: 9,400

SD100

Good

Over: E&E RR

0.9 S I90 INTERCHANGE SF, Minnehaha, SD

Built 2019 Load: 46.2 t ADT: 2,800

191st Street

Good

Over: Foster Creek

4.1W & 1S of Bloomfield, Beadle, SD

Built 1997 Load: 46.3 t ADT: 56

197TH ST

Good

Over: MARSH CK

3 N & 0.2 E BANCROFT, Kingsbury, SD

Built 1992 Load: 46.3 t ADT: 75

I090

Good

Over: BOXELDER CK

1.6 E US 16 B INTERCH, Pennington, SD

Built 1994 Load: 46.3 t ADT: 26,980

47290 305 STR.

Good

Over: BRULE CK

8S & 1.2E BERESFORD, Union, SD

Built 1994 Load: 46.3 t ADT: 40

PINE STREET

Good

Over: MARNE CK

PINE ST - YANKTON, Yankton, SD

Built 2018 Load: 46.3 t ADT: 1,089

411th Avenue

Good

Over: S. Fork of Pearl Creek

10.1S & 2E of Cavour, Beadle, SD

Built 2017 Load: 46.4 t ADT: 56

394th Street

Good

Over: Moccasin Creek

7E & 3.3N of Warner, Brown, SD

Built 2000 Load: 46.4 t ADT: 50

401ST AVENUE

Good

Over: ENEMY CK

5.3S & 4E MT VERNON, Davison, SD

Built 2021 Load: 46.4 t ADT: 64

446th Avenue

Good

Over: Short Foot Creek

1.8N of Veblen, Marshall, SD

Built 2012 Load: 46.4 t ADT: 378

Showing 4,401-4,450 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.