Interstate 15 SB over State Route 78
FairSan Diego County, California · 11-SD-015-R31.48-ESD · Structure no. 57 0814L
- Built
- 1977
- 48 years old
- Condition
- Fair
- inspected March 2024
- Type
- Box Beam or Girders - Multiple
- Prestressed Concrete Continuous
- Length
- 329 ft
- 2 main spans
- Daily traffic
- 64,000
- 2018 count
- Owner
- State
- State Highway Agency
About this bridge
Interstate 15 SB over State Route 78 is a prestressed concrete continuous box beam or girders - multiple carrying Interstate 15 SB over State Route 78 in San Diego County, California. It was built in 1977, so it is 48 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 5 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 64,000 vehicles a day, roughly 7% of them trucks, projected to reach 102,674 by 2046. The structure is 329 ft (100.3 m) long and 82 ft wide. If it were closed, the detour would be 1.2 mi (2 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 | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Interstate 15 SB over State Route 78 built?
It was built in 1977, making it 48 years old in 2025.
What condition is Interstate 15 SB over State Route 78 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 March 2024.
How much traffic does Interstate 15 SB over State Route 78 carry?
About 64,000 vehicles per day (2018 count), of which roughly 7% are trucks.
How long is Interstate 15 SB over State Route 78?
The structure is 329 ft (100.3 m) long with a longest span of 173 ft (52.7 m) and a deck 82 ft wide.
Who owns Interstate 15 SB over State Route 78?
It is owned by the State Highway Agency.