State Route 99 SB over Hamlin Slough
GoodButte County, California · 03-BUT-099-25.35 · Structure no. 12 0131L
- Built
- 1989
- 36 years old
- Condition
- Good
- inspected May 2021
- Type
- Slab
- Concrete Continuous
- Length
- 121 ft
- 4 main spans
- Daily traffic
- 14,125
- 2009 count
- Owner
- State
- State Highway Agency
About this bridge
State Route 99 SB over Hamlin Slough is a concrete continuous slab carrying State Route 99 SB over Hamlin Slough in Butte County, California. It was built in 1989, so it is 36 years old, younger than the California average of 54.8 years.
The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.
It carries about 14,125 vehicles a day, roughly 10% of them trucks, projected to reach 22,909 by 2043. The structure is 121 ft (36.9 m) long and 42 ft wide. If it were closed, the detour would be 1.2 mi (2 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 | 7 Good | Some minor problems. |
| Superstructure | 7 Good | Some minor problems. |
| 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 State Route 99 SB over Hamlin Slough built?
It was built in 1989, making it 36 years old in 2025.
What condition is State Route 99 SB over Hamlin Slough 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 May 2021.
How much traffic does State Route 99 SB over Hamlin Slough carry?
About 14,125 vehicles per day (2009 count), of which roughly 10% are trucks.
How long is State Route 99 SB over Hamlin Slough?
The structure is 121 ft (36.9 m) long with a longest span of 34 ft (10.4 m) and a deck 42 ft wide.
Who owns State Route 99 SB over Hamlin Slough?
It is owned by the State Highway Agency.