Forest Road 309 over Mill Creek
GoodIdaho County, Idaho · 1.9 Mi. from State HWY 14 · Structure no. 011704000014990
- Built
- 2011
- 14 years old
- Condition
- Good
- inspected September 2020
- Type
- Tee Beam
- Prestressed Concrete
- Length
- 71 ft
- 1 main span
- Daily traffic
- 30
- Owner
- Federal
- U.S. Forest Service
About this bridge
Forest Road 309 over Mill Creek is a prestressed concrete tee beam carrying Forest Road 309 over Mill Creek in Idaho County, Idaho. It was built in 2011, so it is 14 years old, younger than the Idaho average of 45.3 years.
The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.
It carries about 30 vehicles a day, projected to reach 45 by 2045. The structure is 71 ft (21.7 m) long and 18 ft wide. If it were closed, the detour would be 98.2 mi (158 km).
Location
Open in Google MapsCondition and inspection
All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 8 Very Good | No problems noted. |
| Superstructure | 8 Very Good | No problems noted. |
| Substructure | 8 Very Good | No problems noted. |
| Channel and channel protection | 8 Very Good | No problems noted. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Forest Road 309 over Mill Creek built?
It was built in 2011, making it 14 years old in 2025.
What condition is Forest Road 309 over Mill Creek in?
The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in September 2020.
How much traffic does Forest Road 309 over Mill Creek carry?
About 30 vehicles per day (latest count).
How long is Forest Road 309 over Mill Creek?
The structure is 71 ft (21.7 m) long with a longest span of 70 ft (21.3 m) and a deck 18 ft wide.
Who owns Forest Road 309 over Mill Creek?
It is owned by the U.S. Forest Service.