IRR I029 S over 146 ST
FairGrant County, South Dakota · 2 S Roberts CO Line · Structure no. 000000026084040
- Built
- 1977
- 48 years old
- Condition
- Fair
- inspected November 2024
- Type
- Slab
- Concrete Continuous
- Length
- 119 ft
- 3 main spans
- Daily traffic
- 3,650
- 2024 count
- Owner
- State
- State Highway Agency
About this bridge
IRR I029 S over 146 ST is a concrete continuous slab carrying IRR I029 S over 146 ST in Grant County, South Dakota. It was built in 1977, so it is 48 years old, younger 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 3,650 vehicles a day, roughly 40% of them trucks, projected to reach 5,146 by 2044. The structure is 119 ft (36.3 m) long and 43 ft wide. If it were closed, the detour would be 0.6 mi (1 km).
Location
Open in Google MapsCondition and inspection
The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 6 Satisfactory | Structural elements show some minor deterioration. |
| Superstructure | 6 Satisfactory | Structural elements show some minor deterioration. |
| Substructure | 6 Satisfactory | Structural elements show some minor deterioration. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was IRR I029 S over 146 ST built?
It was built in 1977, making it 48 years old in 2025.
What condition is IRR I029 S over 146 ST 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 November 2024.
How much traffic does IRR I029 S over 146 ST carry?
About 3,650 vehicles per day (2024 count), of which roughly 40% are trucks.
How long is IRR I029 S over 146 ST?
The structure is 119 ft (36.3 m) long with a longest span of 43 ft (13 m) and a deck 43 ft wide.
Who owns IRR I029 S over 146 ST?
It is owned by the State Highway Agency.