US 20 over South Fork Powder River
FairNatrona County, Wyoming · Casper - Shoshoni · Structure no. CBT
- Built
- 1973
- 52 years old
- Condition
- Fair
- inspected April 2023
- Type
- Stringer/Multi-beam or Girder
- Steel Continuous
- Length
- 280 ft
- 3 main spans
- Daily traffic
- 2,450
- 2024 count
- Owner
- State
- State Highway Agency
About this bridge
US 20 over South Fork Powder River is a steel continuous stringer/multi-beam or girder carrying US 20 over South Fork Powder River in Natrona County, Wyoming. It was built in 1973, so it is 52 years old, older than the Wyoming average of 48.4 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 2,450 vehicles a day, roughly 19% of them trucks, projected to reach 3,430 by 2043. The structure is 280 ft (85.3 m) long and 43 ft wide. If it were closed, the detour would be 80.2 mi (129 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 | 7 Good | Some minor problems. |
| Channel and channel protection | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was US 20 over South Fork Powder River built?
It was built in 1973, making it 52 years old in 2025.
What condition is US 20 over South Fork Powder River 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 April 2023.
How much traffic does US 20 over South Fork Powder River carry?
About 2,450 vehicles per day (2024 count), of which roughly 19% are trucks.
How long is US 20 over South Fork Powder River?
The structure is 280 ft (85.3 m) long with a longest span of 109 ft (33.2 m) and a deck 43 ft wide.
Who owns US 20 over South Fork Powder River?
It is owned by the State Highway Agency.