Johnston Road over Tassajara Creek
FairContra Costa County, California · 0.4 MI E Camino Tassajara · Structure no. 28C0202
- Built
- 1998
- 27 years old
- Condition
- Fair
- inspected November 2024
- Type
- Box Beam or Girders - Multiple
- Concrete
- Length
- 71 ft
- 1 main span
- Daily traffic
- 644
- 2013 count
- Owner
- County
- County Highway Agency
About this bridge
Johnston Road over Tassajara Creek is a concrete box beam or girders - multiple carrying Johnston Road over Tassajara Creek in Contra Costa County, California. It was built in 1998, so it is 27 years old, younger than the California average of 54.8 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 644 vehicles a day, roughly 2% of them trucks, projected to reach 1,249 by 2046. The structure is 71 ft (21.5 m) long and 34 ft wide. If it were closed, the detour would be 1.9 mi (3 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 Johnston Road over Tassajara Creek built?
It was built in 1998, making it 27 years old in 2025.
What condition is Johnston Road over Tassajara Creek 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 Johnston Road over Tassajara Creek carry?
About 644 vehicles per day (2013 count), of which roughly 2% are trucks.
How long is Johnston Road over Tassajara Creek?
The structure is 71 ft (21.5 m) long with a longest span of 68 ft (20.7 m) and a deck 34 ft wide.
Who owns Johnston Road over Tassajara Creek?
It is owned by the County Highway Agency.