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

335 AVENUE

Good

Over: CK

2W & 0.1S JCT 44&47, Gregory, SD

Built 2023 Load: 51.5 t ADT: 15

413th Avenue

Good

Over: Foster Creeck

9.0N & 2.0W of Carpenter, Clark, SD

Built 2012 Load: 51.6 t ADT: 20

SIOUX LAND RD

Good

Over: CK

SUMMERSET, Meade, SD

Built 2008 Load: 51.6 t ADT: 50

157 STREET

Good

Over: NORTH FORK YELLOW BANK R

6E & 4S MILBANK, Grant, SD

Built 1990 Load: 51.7 t ADT: 33

123rd Street

Good

Over: Elm River

3S & 1E of Westport, Brown, SD

Built 2019 Load: 51.8 t ADT: 210

SD025

Good

Over: DAWSON CK

SE CORNER SCOTLAND, Bon Homme, SD

Built 2008 Load: 51.9 t ADT: 888

443 AVENUE

Good

Over: CK

2.2N 1W FLORENCE, Codington, SD

Built 1989 Load: 51.9 t ADT: 73

112th Street

Good

Over: Creek

6.5S & 0.2E of Claire Cty, Roberts, SD

Built 2009 Load: 51.9 t ADT: 23

476TH AVENUE

Good

Over: TRIBUTARY TO SIX MILE CK

2.0W & 3.7N BUSHNELL, Brookings, SD

Built 2005 Load: 52.0 t ADT: 55

IRR SD065

Good

Over: RED EARTH CK

3.1 S JCT SD 20, Ziebach, SD

Built 1984 Load: 52.0 t ADT: 588

45920 299 ST.

Good

Over: FROG CK

2S & 7.1E IRENE, Clay, SD

Built 2009 Load: 52.2 t ADT: 95

260 ST

Good

Over: PLATTE CK

8S 3.3W WHITE LAKE, Aurora, SD

Built 2004 Load: 52.3 t ADT: 82

378th Avenue

Good

Over: Richmond Lake

5.6N & 7.2W of Aberdeen, Brown, SD

Built 2019 Load: 52.3 t ADT: 98

193RD ST

Good

Over: TURTLE CK

9N & 1W WESSINGTON, Hand, SD

Built 1995 Load: 52.3 t ADT: 25

474TH AVENUE

Good

Over: MEDARY CK

2.1E & 4.2S BROOKINGS, Brookings, SD

Built 2003 Load: 52.4 t ADT: 25

SD087

Good

Over: GRACE COOLIDGE CK

4.2 N JCT US 16A, Custer, SD

Built 2005 Load: 52.6 t ADT: 730

241 ST

Good

Over: EAST FORK VERMILLION RV

4.4W ORLAND, Lake, SD

Built 2004 Load: 52.6 t ADT: 175

465th Avenue

Good

Over: Little Minnesota River

7E & 2.5S of Sisseton, Roberts, SD

Built 1996 Load: 52.6 t ADT: 68

485TH AVENUE

Good

Over: CK

2.4N & 1W ELKTON, Brookings, SD

Built 1990 Load: 52.7 t ADT: 92

US081

Good

Over: LITTLE VERMILLION RV

2.6 S MINER CO LINE, McCook, SD

Built 1947 Load: 52.7 t ADT: 1,222

IRR SD046

Good

Over: CK

2.0 E OF WAGNER, Charles Mix, SD

Built 1968 Load: 52.8 t ADT: 1,273

214th Street

Good

Over: S. Fork of Pearl Creek

6S & 2.1W of Iroquois, Beadle, SD

Built 2018 Load: 52.9 t ADT: 34

SD020

Good

Over: LITTLE MISSOURI RV

4.2 E MONTANA STATE LINE, Harding, SD

Built 2021 Load: 52.9 t ADT: 132

SD038

Good

Over: CK

3.3 W I 29 INTERCH, Minnehaha, SD

Built 1949 Load: 53.0 t ADT: 3,892

416th Avenue

Good

Over: Pickerel Creek

6S of Andover, Day, SD

Built 1995 Load: 53.2 t ADT: 42

30260 463 AVE.

Good

Over: CK

5.6S & 11E IRENE, Clay, SD

Built 2017 Load: 53.3 t ADT: 30

SOUTH CONNECTOR

Good

Over: PELICAN LAKE CHANNEL

0.2E & 0.3S OF JCT 20/212, Codington, SD

Built 2012 Load: 53.3 t ADT: 100

156 ST.

Good

Over: CK

4N & 0.3W LEBANON, Potter, SD

Built 1992 Load: 53.4 t ADT: 10

SD046

Good

Over: WEST FORK FROG CK

2.2 E JCT SD 19 N, Clay, SD

Built 2021 Load: 53.5 t ADT: 2,717

181st Street

Good

Over: Big Sioux River

2N & 1.2W of Castlewood, Hamlin, SD

Built 2016 Load: 53.5 t ADT: 66

IRR AR US083

Good

Over: CK

2.3 S JCT SD 44 E, Mellette, SD

Built 1965 Load: 53.5 t ADT: 1,558

SD046

Good

Over: JAMES RV

1.8 W JCT US 81, Yankton, SD

Built 2002 Load: 53.5 t ADT: 809

SD020

Good

Over: THUNDER BUTTE CK

7.7 W OF BISON, Perkins, SD

Built 1983 Load: 53.6 t ADT: 455

SD034

Good

Over: CK

19.2 E JCT US 14 & 83, Hughes, SD

Built 2015 Load: 53.7 t ADT: 658

SD037 N

Good

Over: SAND CK

3.3 S JCT SD 224, Sanborn, SD

Built 1976 Load: 53.7 t ADT: 1,479

US014

Good

Over: FROZENMAN CK

0.3 E OF HAYES, Stanley, SD

Built 2002 Load: 53.8 t ADT: 1,519

SD050

Good

Over: MARNE CK

1.3 W JCT US 81, Yankton, SD

Built 1980 Load: 53.8 t ADT: 3,975

SD025

Good

Over: CK

2.7 S HUTCHINSON CO LINE, Bon Homme, SD

Built 2012 Load: 54.1 t ADT: 888

IRR BIA RTE 121

Good

Over: BIG SPRING CREEK

18.2 KM SW OF SISSETON, Roberts, SD

Built 2018 Load: 54.1 t ADT: 75

483rd Avenue

Good

Over: Mud Creek

2E & 2.2N of Flandreau, Moody, SD

Built 2019 Load: 54.2 t ADT: 175

456th Avenue

Good

Over: W. Brach Little MN River

1W & 6.5N of Sisseton, Roberts, SD

Built 1994 Load: 54.2 t ADT: 20

US016A

Good

Over: LITTLE SQUAW CK

2.5 E JCT SD 87 N, Custer, SD

Built 1987 Load: 54.3 t ADT: 1,335

287 ST

Good

Over: CK

1S & 2.1E Menno, Hutchinson, SD

Built 1990 Load: 54.3 t ADT: 25

127th Street

Good

Over: James River

0.1W of Tacoma Park, Brown, SD

Built 2010 Load: 54.5 t ADT: 313

394TH AVE.

Good

Over: FIRESTEEL CK

15W & 5.9 N MITCHELL, Davison, SD

Built 2022 Load: 54.5 t ADT: 64

468th Avenue

Good

Over: Bull Ditch

0.9S & 2.0W of Colman, Moody, SD

Built 2005 Load: 54.6 t ADT: 35

US012

Good

Over: SPRING LK

2.8 W JCT SD 47 S, Walworth, SD

Built 1986 Load: 54.7 t ADT: 1,087

SD044

Good

Over: RAPID CK

6.4 SE JCT US 385, Pennington, SD

Built 1956 Load: 55.0 t ADT: 3,104

469TH AVENUE

Good

Over: CK

2W & 8.7N BROOKINGS, Brookings, SD

Built 1990 Load: 55.1 t ADT: 92

E. ARDMORE ROAD

Good

Over: LONG BRANCH CK

0.5E ARDMORE, Fall River, SD

Built 2019 Load: 55.2 t ADT: 41

Showing 4,551-4,600 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.