Irr Bia Rte N12 over Slick Rock Creek
Apache County, Arizona · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Irr Bia Rte N12 over Slick Rock Creek in Apache County, Arizona, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the culvert, rated 5 (fair condition) on the 0-9 scale.
- It was built in 1967 and reconstructed in 1984, making it 58 years old at the 2025 inventory.
- It carries about 14,062 vehicles a day (traffic count year 2023).
- It is one of 116 of the 258 inventoried bridges in Apache County rated fair (45.0%); 16 (6.2%) 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 → (35.73203, -109.05797)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Culvert | 5 | Fair condition |
Bridge details
| Structure | Continuous concrete culvert |
| Length | about 39 ft |
| Location | South of Fort Defiance Az |
| NBI structure number | 00000000000N665 |
| Condition class | Fair |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Arizona department of transportation.
Busiest bridges in Apache County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Irr I 40; EB over Black Creek | 1967 | 25,552 | Fair |
| Irr I 40; EB & WB over Wash | 1964 | 25,270 | Good |
| Irr I 40; EB & WB over Cedar Point Wash | 1949 | 25,270 | Good |
| Irr I 40; EB & WB over Wash | 1963 | 22,521 | Good |
| Irr I 40; EB & WB over Wash | 1966 | 22,224 | Fair |
| Irr I 40; EB & WB over Wash | 1962 | 22,224 | Good |
All bridges nearby: Apache County, AZ bridge conditions · every bridge in Apache County · Arizona bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.