US 285 Nbnd over SH 121 Ml
Jefferson County, Colorado · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- US 285 Nbnd over SH 121 Ml in Jefferson County, Colorado, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 7 (good condition) on the 0-9 scale.
- It was built in 2012, making it 13 years old at the 2025 inventory.
- It carries about 24,500 vehicles a day (traffic count year 2020).
- Its listed owner is the state highway agency.
- It is one of 159 of the 468 inventoried bridges in Jefferson County rated good (34.0%); 30 (6.4%) are rated poor.
- A good rating means every major component - deck, superstructure, substructure, or culvert - is rated 7 or higher on FHWA's 0-9 scale: no more than minor problems.
View this bridge on a map → (39.65272, -105.08111)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 8 | Very good condition |
| Superstructure | 7 | Good condition |
| Substructure | 7 | Good condition |
Bridge details
| Structure | Prestressed concrete stringer or multi-beam girder |
| Length | about 147 ft |
| Location | US Hwy 285 over SH 121/WA |
| NBI structure number | F-16-WI |
| Condition class | Good |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Colorado department of transportation.
Busiest bridges in Jefferson County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I 70 Ml over Garrison Street | 1967 | 118,000 | Fair |
| I 70 Ml over Carr Street | 1967 | 118,000 | Fair |
| I 70 Ml over SH 121 Ml | 1996 | 118,000 | Fair |
| US 6 Ml over SH 95 Ml/sheridan Ave. | 2011 | 114,000 | Good |
| I-70 Ml over SH 72 Ml/ward Road | 2024 | 112,000 | Good |
| I70 Ml over Light Rail | 2010 | 106,000 | Fair |
All bridges nearby: Jefferson County, CO bridge conditions · every bridge in Jefferson County · Colorado bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.