US Bridges

SD020 over Trib to Timber Ck

Fair

Spink County, South Dakota · 1.8 W JCT Sd 37 · Structure no. 000000058281060

Built
1958
67 years old
Condition
Fair
inspected June 2024
Type
Slab
Concrete Continuous
Length
117 ft
5 main spans
Daily traffic
590
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 1958, so it is 67 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 590 vehicles a day, roughly 37% of them trucks, projected to reach 803 by 2044. The structure is 117 ft (35.7 m) long and 34 ft wide. If it were closed, the detour would be 14.3 mi (23 km).

CarriesSD020
CrossesTrib to Timber Ck
Location1.8 W JCT Sd 37
RouteState Highway 20
Coordinates45.1547, -98.14407
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
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 rating55.8 US tons
Inventory rating33.4 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans5
Design loadH 20
Structure length117 ft (35.7 m)
Longest span23 ft (7.1 m)
Deck width34 ft (10.5 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic590 (2024)
Projected traffic803 by 2044
Trucks37%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed14.3 mi (23 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 proposedDeck rehabilitation with only incidental widening
Estimated improvement cost$95,000
NavigationNo navigation control on waterway

Frequently asked questions

When was SD020 over Trib to Timber Ck built?

It was built in 1958, making it 67 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 590 vehicles per day (2024 count), of which roughly 37% are trucks.

How long is SD020 over Trib to Timber Ck?

The structure is 117 ft (35.7 m) long with a longest span of 23 ft (7.1 m) and a deck 34 ft wide.

Who owns SD020 over Trib to Timber Ck?

It is owned by the State Highway Agency.