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

I090 W

Unknown

Over: 303 AVE

3 W US 183 S INTERCH, Lyman, SD

Built 1970 ADT: 25

I090 E

Unknown

Over: 303 AVE

3 W US 183 S INTERCH, Lyman, SD

Built 1970 ADT: 25

I090 W

Unknown

Over: 305 AVE

W PRESHO INTERCHANGE, Lyman, SD

Built 1970 ADT: 50

I090 E

Unknown

Over: 305 AVE

W PRESHO INTERCHANGE, Lyman, SD

Built 1970 ADT: 50

I090 W

Unknown

Over: US183

US 183 INTERCHANGE, Lyman, SD

Built 1970 ADT: 621

I090 E

Unknown

Over: US183

US 183 INTERCHANGE, Lyman, SD

Built 1970 ADT: 621

I090 W

Unknown

Over: 308 AVE

2 E US 183 INTERCH, Lyman, SD

Built 1970 ADT: 20

I090 E

Unknown

Over: 308 AVE

2 E US 183 INTERCH, Lyman, SD

Built 1970 ADT: 20

I090 W

Unknown

Over: 310 AVE

4 E US 183 INTERCH, Lyman, SD

Built 1970 ADT: 50

I090 E

Unknown

Over: 310 AVE

4 E US 183 INTERCH, Lyman, SD

Built 1970 ADT: 50

I090 W

Unknown

Over: 312 AVE

6 E US 183 INTERCH, Lyman, SD

Built 1970 ADT: 24

I090 E

Unknown

Over: 312 AVE

6 E US 183 INTERCH, Lyman, SD

Built 1970 ADT: 24

I090 W

Unknown

Over: SD273

KENNEBEC INTERCHANGE, Lyman, SD

Built 1970 ADT: 1,020

I090 E

Unknown

Over: SD273

KENNEBEC INTERCHANGE, Lyman, SD

Built 1970 ADT: 1,020

I090 W

Unknown

Over: 319 AVE

4.3 E KENNEBEC INTERCH, Lyman, SD

Built 1971 ADT: 20

I090 E

Unknown

Over: 319 AVE

4.3 E KENNEBEC INTERCH, Lyman, SD

Built 1971 ADT: 20

I090 W

Unknown

Over: 321 AVE

LYMAN INTERCHANGE, Lyman, SD

Built 1971 ADT: 106

I090 E

Unknown

Over: 321 AVE

LYMAN INTERCHANGE, Lyman, SD

Built 1971 ADT: 106

I090 W

Unknown

Over: 324 AVE

4 W RELIANCE INTERCH, Lyman, SD

Built 1971 ADT: 75

I090 E

Unknown

Over: 324 AVE

4 W RELIANCE INTERCH, Lyman, SD

Built 1971 ADT: 75

I090 W

Unknown

Over: SD248

RELIANCE INTERCHANGE, Lyman, SD

Built 2006 ADT: 850

I090 E

Unknown

Over: SD248

RELIANCE INTERCHANGE, Lyman, SD

Built 2006 ADT: 850

I090 W

Unknown

Over: SD047

SD 47 INTERCHANGE, Lyman, SD

Built 1971 ADT: 282

I090 E

Unknown

Over: SD047

SD 47 INTERCHANGE, Lyman, SD

Built 1971 ADT: 642

I090 W

Unknown

Over: I90 EF

2.8 E SD 47 INTERCH, Lyman, SD

Built 1972 ADT: 2

I090 E

Unknown

Over: I90 EF

2.8 E SD 47 INTERCH, Lyman, SD

Built 1972 ADT: 2

I090 W

Unknown

Over: BIG CK, I90 WF

2.2 W OACOMA INTERCH, Lyman, SD

Built 1971 ADT: 50

I090 E

Unknown

Over: BIG CK, I90 WF

2.2 W OACOMA INTERCH, Lyman, SD

Built 1971 ADT: 50

I090 W

Unknown

Over: COOPER SCHOOL RD

1 W OACOMA INTERCH, Lyman, SD

Built 1971 ADT: 85

I090 E

Unknown

Over: COOPER SCHOOL RD

1 W OACOMA INTERCH, Lyman, SD

Built 1971 ADT: 85

I090 W

Unknown

Over: I090 L

OACOMA INTERCHANGE, Lyman, SD

Built 1971 ADT: 5,450

I090 E

Unknown

Over: I090 L

OACOMA INTERCHANGE, Lyman, SD

Built 1971 ADT: 5,450

431 AVE (FAS 6341)

Unknown

Over: I090

4.0 E SD 25 INTERCHANGE, McCook, SD

Built 1964 ADT: 10,520

435 AVE (FAS 6211)

Unknown

Over: I090

6.0 W US 81 INTERCHANGE, McCook, SD

Built 1964 ADT: 10,280

438 AVE

Unknown

Over: I090

3.0 W US 81 INTERCH, McCook, SD

Built 1964 ADT: 10,400

US081

Unknown

Over: I090

US 81 INTERCHANGE, McCook, SD

Built 1993 ADT: 10,490

I090 W

Unknown

Over: 448 AVE

2 E US 81 INTERCH, McCook, SD

Built 1964 ADT: 45

I090 E

Unknown

Over: 448 AVE

2 E US 81 INTERCH, McCook, SD

Built 1964 ADT: 45

445 AVE (FAS 6355)

Unknown

Over: I090

4 E US 81 INTERCHANGE, McCook, SD

Built 1964 ADT: 10,490

447 AVE

Unknown

Over: I090

6 E US 81 INTERCH, McCook, SD

Built 1964 ADT: 10,410

451 AVE (FAS 6149)

Unknown

Over: I090

MONTROSE INTERCHANGE, McCook, SD

Built 1964 ADT: 10,410

I090 W

Unknown

Over: 453 AVE

1 W MINNEHAHA CO LINE, McCook, SD

Built 1964 ADT: 45

I090 E

Unknown

Over: 453 AVE

1 W MINNEHAHA CO LINE, McCook, SD

Built 1964 ADT: 45

I090 W

Unknown

Over: US014A

EXIT 30 US14A/SD34 INTERC, Meade, SD

Built 1963 ADT: 10,609

I090 E

Unknown

Over: US014A

EXIT 30 US14A INTERCHANGE, Meade, SD

Built 1963 ADT: 10,609

RCP&E RR

Unknown

Over: SHERMAN STREET

SHERMAN ST, Meade, SD

Built 1914 ADT: 1,539

I090 W

Unknown

Over: DOLAN CK RD (FAS)

0.9 NW STURGIS INTERCH, Meade, SD

Built 1963 ADT: 1,250

I090 E

Unknown

Over: DOLAN CK RD (FAS)

0.9 NW STURGIS INTERCH, Meade, SD

Built 1963 ADT: 1,250

RCP&E RR

Unknown

Over: FIFTH STREET

FIFTH ST, Meade, SD

Built 1989 ADT: 2,000

I090 W

Unknown

Over: VANOCKER CANY, RCP&E RR

0.1 NW STRGS INTERCHANGE, Meade, SD

Built 2005 ADT: 7,729

Showing 201-250 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.