ST RTE 99 & Ramps over Mormon Slough
GoodSan Joaquin County, California · 10-SJ-099-17.76 · Structure no. 29 0119
- Built
- 1949
- 76 years old, rebuilt 2016
- Condition
- Good
- inspected June 2024
- Type
- Slab
- Concrete Continuous
- Length
- 103 ft
- 4 main spans
- Daily traffic
- 87,000
- 2009 count
- Owner
- State
- State Highway Agency
About this bridge
ST RTE 99 & Ramps over Mormon Slough is a concrete continuous slab carrying ST RTE 99 & Ramps over Mormon Slough in San Joaquin County, California. It was built in 1949 and reconstructed in 2016, so it is 76 years old, older 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 87,000 vehicles a day, roughly 13% of them trucks, projected to reach 136,355 by 2046. The structure is 103 ft (31.4 m) long and 154 ft wide. 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 |
|---|---|---|
| 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 ST RTE 99 & Ramps over Mormon Slough built?
It was built in 1949, making it 76 years old in 2025. It was reconstructed in 2016.
What condition is ST RTE 99 & Ramps over Mormon 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 June 2024.
How much traffic does ST RTE 99 & Ramps over Mormon Slough carry?
About 87,000 vehicles per day (2009 count), of which roughly 13% are trucks.
How long is ST RTE 99 & Ramps over Mormon Slough?
The structure is 103 ft (31.4 m) long with a longest span of 28 ft (8.5 m) and a deck 154 ft wide.
Who owns ST RTE 99 & Ramps over Mormon Slough?
It is owned by the State Highway Agency.