Irr# US 84 Ml over Rio Blanco
Archuleta County, Colorado · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Irr# US 84 Ml over Rio Blanco in Archuleta County, Colorado, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 5 (fair condition) on the 0-9 scale.
- It was built in 1948, making it 77 years old at the 2025 inventory.
- It carries about 1,300 vehicles a day (traffic count year 2020).
- Its listed owner is the state highway agency.
- It is one of 33 of the 45 inventoried bridges in Archuleta County rated fair (73.3%); 2 (4.4%) 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 May 2023, on a 24-month routine inspection cycle.
- It has fracture-critical members (NBI item 92A): steel tension members without a redundant load path, which get their own scheduled inspections.
- 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 → (37.14205, -106.92362)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 5 | 5 | Fair condition |
| Substructure | 6 | 6 | Satisfactory condition |
Bridge details
| Structure | Steel through truss |
| Length | about 129 ft |
| Location | 16.7 Mi N of New Mexico |
| NBI structure number | P-09-L |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | May 2023 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 8: foundations stable, scour above the top of the footing |
| Fracture critical (item 92A) | Yes |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Colorado department of transportation.
Busiest bridges in Archuleta County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US160 Ml over Mccabe Creek | 2019 | 16,600 | Good |
| US 160 Ml over San Juan River | 1962 | 8,800 | Fair |
| US 160 Ml over Martinez Creek | 1972 | 8,700 | Fair |
| US 160 Ml over Wildlife Crossing | 2022 | 5,500 | Good |
| Hot Springs Blvd. over San Juan River | 1989 | 5,150 | Fair |
| US 160 Ml over Piedra River | 1954 | 4,300 | Fair |
All bridges nearby: Archuleta County, CO bridge conditions · every bridge in Archuleta County · Colorado bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.