County Road 77 over Rock Creek
Park County, Colorado · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- County Road 77 over Rock Creek in Park County, Colorado, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the culvert, rated 7 (good condition) on the 0-9 scale.
- It was built in 2006, making it 19 years old at the 2025 inventory.
- It carries about 350 vehicles a day (traffic count year 2020).
- Its listed owner is the county highway agency.
- It is one of 18 of the 55 inventoried bridges in Park County rated good (32.7%); 3 (5.5%) 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 → (39.29154, -105.69736)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Culvert | 7 | Good condition |
Bridge details
| Structure | Aluminum or iron culvert |
| Length | about 27 ft |
| Location | 9.6 Mi SE of US 285 |
| NBI structure number | PA77-S9.6-S285 |
| Condition class | Good |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Colorado department of transportation.
Busiest bridges in Park County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 285 Ml over Deer Creek | 1958 | 14,000 | Fair |
| US 285 Ml over Middle Fk So Platte Rvr | 2024 | 8,000 | Good |
| US 285 Ml over Trout Creek | 1937 | 7,200 | Fair |
| US 285 Ml over N. Fork S. Platte River | 1962 | 6,400 | Fair |
| US 285 Ml over Geneva Creek | 1989 | 6,400 | Fair |
| US 285 Ml over N Fk South Platte Rvr | 1989 | 5,900 | Fair |
All bridges nearby: Park County, CO bridge conditions · every bridge in Park County · Colorado bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.