FM 3406 over Onion Branch
GoodWilliamson County, Texas · 0.5 MI W of IH 35 · Structure no. 142460137806030
- Built
- 1980
- 45 years old, rebuilt 2017
- Condition
- Good
- inspected December 2023
- Type
- Culvert
- Concrete
- Length
- 43 ft
- 4 main spans
- Daily traffic
- 8,649
- 2020 count
- Owner
- City
- City or Municipal Highway Agency
About this bridge
FM 3406 over Onion Branch is a concrete culvert carrying FM 3406 over Onion Branch in Williamson County, Texas. It was built in 1980 and reconstructed in 2017, so it is 45 years old, older than the Texas average of 44.4 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 8,649 vehicles a day, roughly 3% of them trucks, projected to reach 13,890 by 2033. The structure is 43 ft (13.1 m) long. If it were closed, the detour would be 3.1 mi (5 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 |
|---|---|---|
| Channel and channel protection | 8 Very Good | No problems noted. |
| Culvert | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was FM 3406 over Onion Branch built?
It was built in 1980, making it 45 years old in 2025. It was reconstructed in 2017.
What condition is FM 3406 over Onion Branch 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 December 2023.
How much traffic does FM 3406 over Onion Branch carry?
About 8,649 vehicles per day (2020 count), of which roughly 3% are trucks.
How long is FM 3406 over Onion Branch?
The structure is 43 ft (13.1 m) long with a longest span of 10 ft (3 m).
Who owns FM 3406 over Onion Branch?
It is owned by the City or Municipal Highway Agency.