SH 121 Ml over Clear Creek
Jefferson County, Colorado · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- SH 121 Ml over Clear Creek in Jefferson County, Colorado, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 5 (fair condition) on the 0-9 scale.
- It was built in 1941 and reconstructed in 1980, making it 84 years old at the 2025 inventory.
- It carries about 38,000 vehicles a day (traffic count year 2020).
- Its listed owner is the state highway agency.
- It is one of 279 of the 468 inventoried bridges in Jefferson County rated fair (59.6%); 30 (6.4%) 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: deck 6 to 5, superstructure 6 to 5.
- Its most recent inspection on record is dated January 2025, 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 → (39.78421, -105.08121)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 5 | Fair condition |
| Superstructure | 6 | 5 | Fair condition |
| Substructure | 5 | 5 | Fair condition |
Bridge details
| Structure | Steel stringer or multi-beam girder |
| Length | about 156 ft |
| Location | S. edge 70 76 ramp 121 |
| NBI structure number | E-16-O |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | January 2025 |
| 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 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.