State profile · Above median Poor share

South Dakota bridge safety

Condition ratings, load ratings, and Poor-condition data for every public highway bridge in South Dakota, based on the FHWA National Bridge Inventory.

5,905
Public bridges
31.9%
Good condition
16.2%
Poor condition

Data updated May 2026

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 whose lowest applicable component is rated 0-4

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 - Poor-condition share 54.1%
National avg

Lower is better. Bar maxes at 30% (worst-state ceiling). National average sits at 7.0%.

South Dakota vs nearby ranks

Adjacent states by Poor-condition share (lower share = better)

States are ranked by the share of bridges whose lowest applicable component rating is 4 or below. This describes recorded condition; it does not measure funding effectiveness or live crossing safety. States here sit immediately above and below South Dakota on the same metric.

GU

Guam

15.25% top marginal rate
Structure
Progressive
Burden @ $100K
$59

WV

West Virginia

16.02% top marginal rate
Structure
Progressive
Burden @ $100K
$7,679
Selected

SD

South Dakota

16.24% top marginal rate
Structure
Progressive
Burden @ $100K
$5,905

IA

Iowa

20.01% top marginal rate
Structure
Progressive
Burden @ $100K
$20,753

VI

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 the portal's composite display score. Inspection intervals are risk-based under current NBIS rules.

All Bridges in South Dakota

IRR US018

Fair

Over: WHITE RV

10 E FALL RIVER CO LINE, Oglala Lakota, SD

Built 1953 Load: 32.6 t ADT: 1,463

SD037

Fair

Over: FORDHAM CK

7.7 N JCT US 212, Spink, SD

Built 1958 Load: 32.6 t ADT: 446

IRR BIA RTE 6

Fair

Over: RATTLESNAKE CREEK

13.0 KM SE RED SCAFFOLD, Ziebach, SD

Built 1986 Load: 32.6 t ADT: 293

US281

Fair

Over: WEST BR FIRESTEEL CK

8.5 N I 90 INTERCH, Aurora, SD

Built 1959 Load: 32.7 t ADT: 1,296

155 STREET

Fair

Over: BIG SIOUX RV

6.7E & 6N FLORENCE, Codington, SD

Built 1996 Load: 32.7 t ADT: 16

453 AVENUE

Fair

Over: SOO CK

8.5E 4.2N FLORENCE, Codington, SD

Built 1980 Load: 32.7 t ADT: 73

43RD ST., WTN.

Fair

Over: WILLOW CK

3.0E 1.9N WATERTOWN, Codington, SD

Built 1996 Load: 32.7 t ADT: 73

459 AVE

Fair

Over: WILLOW CK

4.0E 1.4N WATERTOWN, Codington, SD

Built 2006 Load: 32.7 t ADT: 100

OAK STREET

Fair

Over: WILLOW CK

5.9E 3.6N WATERTOWN, Codington, SD

Built 1988 Load: 32.7 t ADT: 40

177 ST

Fair

Over: STRAY HORSE CK

5.0S KRANZBURG, Codington, SD

Built 2006 Load: 32.7 t ADT: 20

HASSELSTROM PLACE

Fair

Over: BATTLE CK

1S HERMOSA, Custer, SD

Built 1982 Load: 32.7 t ADT: 15

TWNSHP RD 477TH AV

Fair

Over: CK

3.2N,1E TUNERVILLE, Deuel, SD

Built 1982 Load: 32.7 t ADT: 35

TWNSHP RD 168TH ST

Fair

Over: CK

1.2E & 4N TUNERVILLE, Deuel, SD

Built 1988 Load: 32.7 t ADT: 35

160TH ST

Fair

Over: SOUTH FORK SNAKE CK

8.5E & 2.5N FAULKTON, Faulk, SD

Built 2003 Load: 32.7 t ADT: 15

154 STREET

Fair

Over: BIG SIOUX RV

3N & 12.7W S SHORE, Grant, SD

Built 1992 Load: 32.7 t ADT: 52

452 AVENUE

Fair

Over: BIG SIOUX RV

12.5W & 1.5N MARVIN, Grant, SD

Built 1996 Load: 32.7 t ADT: 25

452 AVE

Fair

Over: BIG SIOUX RV

12.5W & 4.0S MARVIN, Grant, SD

Built 2004 Load: 32.7 t ADT: 25

452 AVE

Fair

Over: INDIAN RV

6.0S & 12.5W MARVIN, Grant, SD

Built 2004 Load: 32.7 t ADT: 12

145 ST

Fair

Over: CK

12.6W & 1.5N MARVIN, Grant, SD

Built 2008 Load: 32.7 t ADT: 35

150 STREET

Fair

Over: BIG SIOUX RV

12.5W & 3.5S MARVIN, Grant, SD

Built 2010 Load: 32.7 t ADT: 52

468 AVENUE

Fair

Over: CK

3.3E & 2.9N MARVIN, Grant, SD

Built 2009 Load: 32.7 t ADT: 25

143 STREET

Fair

Over: CK

3.5N & 4.5E MARVIN, Grant, SD

Built 1998 Load: 32.7 t ADT: 52

473 AVENUE

Fair

Over: CK

5W & 2.1S MILBANK, Grant, SD

Built 2007 Load: 32.7 t ADT: 20

474 AVENUE

Fair

Over: CK

4W & 6.5N MILBANK, Grant, SD

Built 2002 Load: 32.7 t ADT: 52

475TH AVENUE

Fair

Over: CK

3W & 3.1N MILBANK, Grant, SD

Built 2000 Load: 32.7 t ADT: 20

155 STREET

Fair

Over: CK

2.7 W & 6.0 S of Milbank, Grant, SD

Built 2002 Load: 32.7 t ADT: 52

153 STREET

Fair

Over: CK

2.1W & 3S MILBANK, Grant, SD

Built 2012 Load: 32.7 t ADT: 52

477 AVENUE

Fair

Over: CK

1W & 3.6N MILBANK, Grant, SD

Built 2014 Load: 32.7 t ADT: 20

477 AVENUE

Fair

Over: SOUTH FORK WHETSTONE RV

1W & 0.2N MILBANK, Grant, SD

Built 1989 Load: 32.7 t ADT: 30

477 AVENUE

Fair

Over: CK

1W & 4.9S MILBANK, Grant, SD

Built 2013 Load: 32.7 t ADT: 70

477 AVE

Fair

Over: CK

5.0W & 0.9N ALBEE, Grant, SD

Built 2004 Load: 32.7 t ADT: 25

479 AVENUE

Fair

Over: SOUTH FORK WHETSTONE RV

1E & 0.6N MILBANK, Grant, SD

Built 2003 Load: 32.7 t ADT: 40

148 STREET

Fair

Over: CK

1.8E & 0.9N MILBANK, Grant, SD

Built 1992 Load: 32.7 t ADT: 35

147 ST

Fair

Over: SOUTH FORK WHETSTONE RV

3.0E & 1.5N MILBANK, Grant, SD

Built 2006 Load: 32.7 t ADT: 45

485 AVENUE

Fair

Over: BURLINGTON NORTHERN RR

1S & 1.5W BIG STONE, Grant, SD

Built 1978 Load: 32.7 t ADT: 397

153 STREET

Fair

Over: NORTH FORK YELLOW BANK R

7.8E & 4S MILBANK, Grant, SD

Built 1979 Load: 32.7 t ADT: 31

298 STREET

Fair

Over: WILLOW CK

9.1W BONESTEEL, Gregory, SD

Built 1930 Load: 32.7 t ADT: 36

FAS 6188

Fair

Over: NORTH FORK BAD RV

8 W 3.2 N PHILIP, Haakon, SD

Built 1960 Load: 32.7 t ADT: 86

US014

Fair

Over: GRINDSTONE CK

2.6 E OF PHILIP, Haakon, SD

Built 1955 Load: 32.7 t ADT: 725

Northwestern Ave

Fair

Over: BAD RV

0.9 E & 0.2 S MIDLND, Haakon, SD

Built 1970 Load: 32.7 t ADT: 60

SD042

Fair

Over: BLOOM CK

9.5 E DAVISON CO LINE, Hanson, SD

Built 1959 Load: 32.7 t ADT: 356

SD042

Fair

Over: BLOOM CK

10.4 E DAVISON CO LINE, Hanson, SD

Built 1959 Load: 32.7 t ADT: 356

448 AVE

Fair

Over: EAST FORK VERMILLION RV

3W & 1.8S ORLAND, Lake, SD

Built 1997 Load: 32.7 t ADT: 42

243 ST

Fair

Over: EAST FORK VERMILLION RV

2.9W & 2.0S ORLAND, Lake, SD

Built 1997 Load: 32.7 t ADT: 42

CITY STREET

Fair

Over: SILVER CK

UNION AVE S - MADISON, Lake, SD

Built 1978 Load: 32.7 t ADT: 100

500 N EGAN AVE

Fair

Over: MADISON CK

EGAN AVE N - MADISON, Lake, SD

Built 1993 Load: 32.7 t ADT: 3,190

610 S. EGAN AVENUE

Fair

Over: SILVER CK

EGAN AVE S - MADISON, Lake, SD

Built 1979 Load: 32.7 t ADT: 2,915

JACKSON BLVD

Fair

Over: SPEARFISH CK

JACKSON BLVD - SPEARFISH, Lawrence, SD

Built 1966 Load: 32.7 t ADT: 12,135

GRANT STREET

Fair

Over: SPEARFISH CK

GRANT ST - SPEARFISH, Lawrence, SD

Built 1988 Load: 32.7 t ADT: 3,981

8th Street

Fair

Over: Big Sioux River

E of Phillips Avenue - SF, Minnehaha, SD

Built 1912 Load: 32.7 t ADT: 7,100

Showing 2,201-2,250 of 5,905 bridges

Data sourced from the FHWA National Bridge Inventory (NBI), latest released cycle. See our methodology for details. Retrieved and formatted by PlainBridges.

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). Poor condition is an inspection-record category, not a closure or unsafe-to-cross designation. Consult the bridge owner for current status.

Every figure on PlainBridge is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.