County Road 45B over Little Thompson River
Larimer County, Colorado · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- County Road 45B over Little Thompson River in Larimer 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 2015, making it 10 years old at the 2025 inventory.
- It carries about 122 vehicles a day (traffic count year 2023).
- Its listed owner is the county highway agency.
- It is one of 275 of the 562 inventoried bridges in Larimer County rated good (48.9%); 12 (2.1%) 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 → (40.28733, -105.34558)
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 multiple box beam |
| Length | about 70 ft |
| Location | 1.0 mile east 36 |
| NBI structure number | LR45B-0.1-4F-A |
| Condition class | Good |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Colorado department of transportation.
Busiest bridges in Larimer County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I25 Ml Nbnd over Poudre River Floodplain | 2022 | 90,000 | Good |
| I25 Ml Sbnd over Poudre River Floodplain | 2023 | 90,000 | Good |
| I 25 Ml over Hillsboro Tributary | 2020 | 86,000 | Good |
| I 25 Ml Nbnd over County Road 16 | 2022 | 86,000 | Good |
| I 25 Ml Sbnd over County Road 16 | 2023 | 86,000 | Good |
| SH 402 Ml over I25 Ml | 2020 | 86,000 | Good |
All bridges nearby: Larimer County, CO bridge conditions · every bridge in Larimer County · Colorado bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.