US Bridges

SD020 over Trib to Timber Ck

Fair

Spink County, South Dakota · 0.8 S JCT Sd 20 W & 37 · Structure no. 000000058300068

Built
1955
70 years old
Condition
Fair
inspected June 2024
Type
Slab
Concrete Continuous
Length
87 ft
3 main spans
Daily traffic
875
2024 count
Owner
State
State Highway Agency

About this bridge

SD020 over Trib to Timber Ck is a concrete continuous slab carrying SD020 over Trib to Timber Ck in Spink County, South Dakota. It was built in 1955, so it is 70 years old, older than the South Dakota average of 48.9 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 875 vehicles a day, roughly 17% of them trucks, projected to reach 1,191 by 2044. The structure is 87 ft (26.4 m) long and 34 ft wide. If it were closed, the detour would be 72.7 mi (117 km).

CarriesSD020
CrossesTrib to Timber Ck
Location0.8 S JCT Sd 20 W & 37
RouteState Highway 20
Coordinates45.14281, -98.1047
Functional classRural Minor Arterial

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating62.4 US tons
Inventory rating37.4 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length87 ft (26.4 m)
Longest span31 ft (9.4 m)
Deck width34 ft (10.5 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic875 (2024)
Projected traffic1,191 by 2044
Trucks17%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed72.7 mi (117 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was SD020 over Trib to Timber Ck built?

It was built in 1955, making it 70 years old in 2025.

What condition is SD020 over Trib to Timber Ck in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in June 2024.

How much traffic does SD020 over Trib to Timber Ck carry?

About 875 vehicles per day (2024 count), of which roughly 17% are trucks.

How long is SD020 over Trib to Timber Ck?

The structure is 87 ft (26.4 m) long with a longest span of 31 ft (9.4 m) and a deck 34 ft wide.

Who owns SD020 over Trib to Timber Ck?

It is owned by the State Highway Agency.