SH 9 Ml over Blue River
Summit County, Colorado · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- SH 9 Ml over Blue River in Summit County, Colorado, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 7 (good condition) on the 0-9 scale.
- It was built in 2008, making it 17 years old at the 2025 inventory.
- It carries about 20,000 vehicles a day (traffic count year 2020).
- Its listed owner is the state highway agency.
- It is one of 16 of the 63 inventoried bridges in Summit County rated good (25.4%); 5 (7.9%) 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 April 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 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 → (39.49072, -106.04611)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 7 | 7 | Good condition |
| Superstructure | 7 | 7 | Good condition |
| Substructure | 7 | 7 | Good condition |
Bridge details
| Structure | Steel single box beam |
| Length | about 111 ft |
| Location | SH 9 over Blue River |
| NBI structure number | F-12-CA |
| Condition class | Good |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | April 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 Summit County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I 70 Wbnd over Forest Service Road | 2021 | 36,000 | Good |
| I 70 Ebnd over Forest Service Road | 2021 | 36,000 | Good |
| I 70 Ml over County Road | 1977 | 27,000 | Good |
| SH 9 Ml over Tenmile Creek | 1980 | 24,000 | Fair |
| SH 9 Ml over I 70 Ml | 1971 | 24,000 | Fair |
| SH 9 Ml over Pedestrian Underpass | 2023 | 22,287 | Good |
All bridges nearby: Summit County, CO bridge conditions · every bridge in Summit County · Colorado bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.