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

47920 310TH ST

Good

Over: WEST UNION CK

8.5S & 0.2E ALCESTER, Union, SD

Built 2020 Load: 37.2 t ADT: 40

US281

Good

Over: CK

4.9 N I90 INTERCHANGE, Aurora, SD

Built 1960 Load: 37.3 t ADT: 1,296

31080 459 AVE.

Good

Over: CLAY CK DITCH

13.8S & 6.8E IRENE, Clay, SD

Built 1996 Load: 37.3 t ADT: 35

IRR BIA RTE 3

Good

Over: MOREAU RIVER

3.8 KM SE OF WHITEHORSE, Dewey, SD

Built 1987 Load: 37.3 t ADT: 305

Nolan Road

Good

Over: INDIAN CK

15.8 E & 1 S PHILIP, Haakon, SD

Built 2002 Load: 37.3 t ADT: 5

US018

Good

Over: SNAKE CK

1.6 W I 29 INTERCH, Lincoln, SD

Built 2018 Load: 37.3 t ADT: 2,058

57th Street

Good

Over: Drainage Channel

east of Louise Avenue, Minnehaha, SD

Built 1997 Load: 37.3 t ADT: 12,500

SD034

Good

Over: REDWATER CANAL

1.9 NW LAWRENCE CO LINE, Butte, SD

Built 1964 Load: 37.6 t ADT: 3,278

County Road

Good

Over: Slaughter Creek

0.8E of Greenwood, Charles Mix, SD

Built 1974 Load: 37.6 t ADT: 50

314th Ave

Good

Over: ENEMY CK

8W & 2.9S of Alexandria, Hanson, SD

Built 2021 Load: 37.6 t ADT: 23

478th Avenue

Good

Over: Trib. to E Brule Creek

6E & 0.9N of Beresford, Lincoln, SD

Built 1990 Load: 37.6 t ADT: 75

302nd Avenue

Good

Over: Cedar Creek

3.4W & 16.2N of Presho, Lyman, SD

Built 1986 Load: 37.6 t ADT: 47

38910 284th Street

Good

Over: Andes Creek

8.0N & 7.1E of Lake Andes, Charles Mix, SD

Built 2015 Load: 37.7 t ADT: 15

IRR BIA RTE 4

Good

Over: LITTLE OAK CREEK

5.8KM SW OF LITTLE EAGLE, Corson, SD

Built 2002 Load: 37.7 t ADT: 116

IRR BIA RTE 4

Good

Over: HIGHBANK CREEK BRIDGE

8.93KM SW OF LITTLE EAGLE, Corson, SD

Built 2008 Load: 37.7 t ADT: 109

404TH AVENUE

Good

Over: FIRESTEEL CK

1.5S 1.0W LOOMIS, Davison, SD

Built 2023 Load: 37.7 t ADT: 64

KIRK ROAD

Good

Over: CK

1.0E 0.5S LEAD, Lawrence, SD

Built 1992 Load: 37.7 t ADT: 69

239 ST

Good

Over: WEST FORK VERMILLION RV

3N & 1.1E CANOVA, Miner, SD

Built 1997 Load: 37.7 t ADT: 15

WALNUT STREET

Good

Over: MARNE CREEK

WALNUT STREET - YANKTON, Yankton, SD

Built 1999 Load: 37.7 t ADT: 2,700

104th Street

Good

Over: James River

0.35 & 1.8W of Hecla, Brown, SD

Built 2016 Load: 37.8 t ADT: 456

407th Avenue

Good

Over: Creek

1E & 0.5N of Ferney, Brown, SD

Built 2019 Load: 37.8 t ADT: 98

198TH STREET

Good

Over: CK

2 N & 3.4 E BADGER, Kingsbury, SD

Built 2023 Load: 37.8 t ADT: 7

I090 W

Good

Over: EAST FORK VERMILLION RV

2.1 W MINNEHAHA CO LINE, McCook, SD

Built 2022 Load: 37.8 t ADT: 6,685

I090 E

Good

Over: EAST FORK VERMILLION RV

2.1 W MINNEHAHA CO LINE, McCook, SD

Built 2021 Load: 37.8 t ADT: 6,685

SD019

Good

Over: VERMILLION RV

0.8 W JCT SD 19 N, Clay, SD

Built 1997 Load: 37.9 t ADT: 2,342

N 2ND ST OLD HWY79

Good

Over: CK

0.2 N OF HERMOSA, Custer, SD

Built 2021 Load: 37.9 t ADT: 150

US385

Good

Over: HORSEHEAD CK

4.9 S OF JCT US18EAST, Fall River, SD

Built 2014 Load: 37.9 t ADT: 673

Alcorn Ridge Road

Good

Over: POLO CK

0.9E JCT US85S -SPEARFISH, Lawrence, SD

Built 2018 Load: 37.9 t ADT: 1,000

FDR 181

Good

Over: CASTLE CREEK

T 1 N R 3 E SEC 2, Pennington, SD

Built 1954 Load: 37.9 t ADT: 25

IRR SD046

Good

Over: CHOTEAU CK

1.3 E OF WAGNER, Charles Mix, SD

Built 1968 Load: 38.0 t ADT: 1,273

IRR COUNTY ROAD

Good

Over: Creek

0.5E WHITE HORSE, Dewey, SD

Built 2020 Load: 38.0 t ADT: 451

483rd Avenue

Good

Over: Trib. to Pattee Creek

11E & 4.1N of Beresford, Lincoln, SD

Built 2020 Load: 38.0 t ADT: 45

391 AVE

Good

Over: CK

5E and 2.6N PLANKINTON, Aurora, SD

Built 2021 Load: 38.1 t ADT: 33

3rd Avenue SE

Good

Over: Moccasin Creek

3rd Ave. SE - Aberdeen, Brown, SD

Built 2019 Load: 38.1 t ADT: 5,087

IRR SD050

Good

Over: CROW CK

7.2 S JCT SD 34, Buffalo, SD

Built 1999 Load: 38.1 t ADT: 954

170 STREET

Good

Over: WILLOW CK

4.9E 2N WATERTOWN, Codington, SD

Built 1995 Load: 38.1 t ADT: 49

480 AVENUE

Good

Over: NORTH FORK WHETSTONE RV

4N & 2E MILBANK, Grant, SD

Built 2018 Load: 38.1 t ADT: 200

226 ST

Good

Over: BATTLE CK

1.9E & 1N RUTLAND, Lake, SD

Built 2016 Load: 38.1 t ADT: 15

I029 S

Good

Over: BIG SIOUX RV

AT IOWA STATE LINE, Union, SD

Built 1990 Load: 38.1 t ADT: 19,000

46030 312 ST.

Good

Over: CLAY CK DITCH

15S & 8.3E IRENE, Clay, SD

Built 1996 Load: 38.2 t ADT: 25

IRR SD065

Good

Over: GRAND RV

15 N DEWEY CO LINE, Corson, SD

Built 2012 Load: 38.2 t ADT: 244

I090 E

Good

Over: BEAR BUTTE CK

0.4 W US 14A INTERCH, Meade, SD

Built 1963 Load: 38.2 t ADT: 7,485

266TH ST, HWY 146

Good

Over: TRIB TO FOUR MILE CK

4S & 1.8W VALLEY SPRINGS, Minnehaha, SD

Built 2020 Load: 38.2 t ADT: 1,502

391 AVE

Good

Over: CK

5E 4.1N PLANKINTON, Aurora, SD

Built 2020 Load: 38.3 t ADT: 33

SD044

Good

Over: BULL CK

1.4 E TRIPP CO LINE, Gregory, SD

Built 1971 Load: 38.3 t ADT: 568

SD079

Good

Over: CK

14.2 S NORTH DAKOTA LINE, Harding, SD

Built 1962 Load: 38.3 t ADT: 357

IRR BIA RTE 6

Good

Over: ASH CREEK

19KM WEST OF CHERRY CREEK, Ziebach, SD

Built 1968 Load: 38.3 t ADT: 814

US081

Good

Over: CK

4.5 W JCT US 81 N, Lake, SD

Built 1997 Load: 38.4 t ADT: 1,744

282nd Street

Good

Over: East Fork of Long Creek

3S & 0.1E of Lennox, Lincoln, SD

Built 1991 Load: 38.4 t ADT: 350

COUNTY RD

Good

Over: DRAINAGE DITCH

9.2S PARKER, Turner, SD

Built 2016 Load: 38.4 t ADT: 25

Showing 4,101-4,150 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.