SR-121 over S. Prong St.marys River
Baker County, Florida · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- SR-121 over S. Prong St.marys River in Baker County, Florida, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 5 (fair condition) on the 0-9 scale.
- It was built in 1962, making it 63 years old at the 2025 inventory.
- It carries about 2,967 vehicles a day (traffic count year 2022).
- Its listed owner is the state highway agency.
- It is one of 58 of the 92 inventoried bridges in Baker County rated fair (63.0%); 9 (9.8%) are rated poor.
- A fair rating means the lowest-rated major component scores 5 or 6 on FHWA's 0-9 scale: some deterioration or minor section loss, but the structure is sound. It is the middle class, not a warning.
View this bridge on a map → (30.35226, -82.1291)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 5 | Fair condition |
| Superstructure | 5 | Fair condition |
| Substructure | 5 | Fair condition |
Bridge details
| Structure | Prestressed concrete slab |
| Length | about 240 ft |
| Location | 1.3 Mi. N. of Cr-23c |
| NBI structure number | 270009 |
| Condition class | Fair |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Florida department of transportation.
Busiest bridges in Baker County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I-10 (SR-8) over Prong of St.marys River | 1961 | 32,500 | Fair |
| I-10 SR-8 over Turkey Creek | 1961 | 29,000 | Fair |
| I-10 SR-8 over Hells Bay | 1961 | 27,000 | Fair |
| I-10 (SR-8) over Cypress Branch | 1962 | 25,243 | Good |
| I-10 WB SR-8 over Csxrr Removed | 1960 | 20,000 | Fair |
| I-10 EB SR-8 over SR-228 | 1960 | 20,000 | Fair |
All bridges nearby: Baker County, FL bridge conditions · every bridge in Baker County · Florida bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.