Parnum Road (US20 over North Fork Cache Creek
Lake County, California · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Parnum Road (US20 over North Fork Cache Creek in Lake County, California, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 8 (very good condition) on the 0-9 scale.
- It was built in 2021, making it 4 years old at the 2025 inventory.
- It carries about 1 vehicles a day (traffic count year 2023).
- It is one of 40 of the 131 inventoried bridges in Lake County rated good (30.5%); 12 (9.2%) 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 → (39.00062, -122.55565)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 8 | Very good condition |
| Superstructure | 8 | Very good condition |
| Substructure | 8 | Very good condition |
Bridge details
| Structure | Steel through truss |
| Length | about 103 ft |
| Location | 4.7 Miles NW of Clearlake |
| NBI structure number | 0000000L2132227 |
| Condition class | Good |
Source: FHWA National Bridge Inventory, 2025 data as reported by the California department of transportation.
Busiest bridges in Lake County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| State Route 53 over Seigler Creek | 1952 | 16,500 | Fair |
| State Route 29 over Kelsey Creek | 1966 | 12,100 | Good |
| State Route 29 over Adobe Creek | 1966 | 12,100 | Good |
| State Route 29 over Hill Creek | 1966 | 12,100 | Good |
| State Route 29 over Manning Creek | 1966 | 12,100 | Good |
| State Route 29 over Putah Creek | 2003 | 10,900 | Good |
All bridges nearby: Lake County, CA bridge conditions · every bridge in Lake County · California bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.