21ST Avenue over LITTLE McPHERSON BAYOU
Pinellas County, Florida · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- 21ST Avenue over LITTLE McPHERSON BAYOU in Pinellas County, Florida, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1954 and reconstructed in 1980, making it 71 years old at the 2025 inventory.
- It carries about 3,046 vehicles a day (traffic count year 2023).
- Its listed owner is a city or municipal highway agency.
- It is one of 154 of the 449 inventoried bridges in Pinellas County rated fair (34.3%); 8 (1.8%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- Its condition class and component ratings are unchanged from the 2024 inventory.
- Its most recent inspection on record is dated July 2023, on a 24-month routine inspection cycle.
- It is coded scour critical (NBI item 113 = 3): scour critical: foundations unstable for the assessed or calculated scour.
- 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 → (27.6972, -82.73489)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 7 | 7 | Good condition |
| Superstructure | 7 | 7 | Good condition |
| Substructure | 6 | 6 | Satisfactory condition |
Bridge details
| Structure | Prestressed concrete stringer or multi-beam girder |
| Length | about 290 ft |
| Location | Pass-a-grille Way |
| NBI structure number | 157501 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | July 2023 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 3: scour critical: foundations unstable for the assessed or calculated scour |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Florida department of transportation.
Busiest bridges in Pinellas County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I-275 SB over 30TH Ave North | 1974 | 158,000 | Good |
| I-275 SB over 22ND Avenue North | 1974 | 158,000 | Good |
| I-275 NB over 22ND Ave North | 1974 | 158,000 | Good |
| I-275 SB over 38TH Avenue North | 1974 | 158,000 | Good |
| I-275 NB over 38TH Avenue North | 1974 | 158,000 | Good |
| I-275 SB over 50TH Ave N SR-689 | 1972 | 155,500 | Good |
All bridges nearby: Pinellas County, FL bridge conditions · every bridge in Pinellas County · Florida bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.