Box Canyon over Box Canyon
Pima County, Arizona · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Box Canyon over Box Canyon in Pima County, Arizona, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 5 (fair condition) on the 0-9 scale.
- It was built in 1954, making it 71 years old at the 2025 inventory.
- It carries about 80 vehicles a day (traffic count year 2022).
- It is one of 361 of the 1,154 inventoried bridges in Pima County rated fair (31.3%); 11 (1.0%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- Its class is unchanged from 2024 (fair), but component ratings moved: substructure 6 to 5.
- Its most recent inspection on record is dated April 2024, on a 24-month routine inspection cycle.
- 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 → (31.79922, -110.79746)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 6 | 6 | Satisfactory condition |
| Substructure | 6 | 5 | Fair condition |
Bridge details
| Structure | Concrete slab |
| Length | about 80 ft |
| Location | .9 Mi Sw/o Basin Spring |
| NBI structure number | 030502000003263 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | April 2024 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 5: foundations stable, scour within the limits of the footing or piles |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Arizona department of transportation.
Busiest bridges in Pima County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Ramp to I-10 NW over I 10 Mainline | 2003 | 281,068 | Fair |
| I-10 EB & WB over Cushing Street | 2009 | 209,279 | Good |
| I-10 EB & WB over 18th Street | 2009 | 209,269 | Good |
| I-10 EB & WB over Congress Street | 2009 | 195,388 | Good |
| I-10 over St. Marys Rd | 2009 | 195,068 | Fair |
| I-10 over Speedway Blvd. | 2009 | 195,068 | Good |
All bridges nearby: Pima County, AZ bridge conditions · every bridge in Pima County · Arizona bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.