Irr County Rd 306 over Watson Creek
Glenn County, California · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Irr County Rd 306 over Watson Creek in Glenn County, California, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 4 (poor condition) on the 0-9 scale.
- It was built in 1930 and reconstructed in 1980, making it 95 years old at the 2025 inventory.
- It carries about 268 vehicles a day (traffic count year 2004).
- Its listed owner is the county highway agency.
- It is one of 17 of the 240 inventoried bridges in Glenn County rated poor (7.1%); 17 (7.1%) 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 August 2023, on a 24-month routine inspection cycle.
- A poor rating means at least one major component - deck, superstructure, or substructure - is rated 4 or lower on FHWA's 0-9 scale. It does not by itself mean the bridge is unsafe; bridges judged unsafe are closed or load-restricted by their owners.
View this bridge on a map → (39.68277, -122.53617)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 7 | 7 | Good condition |
| Superstructure | 7 | 7 | Good condition |
| Substructure | 4 | 4 | Poor condition |
Bridge details
| Structure | Concrete girder and floorbeam |
| Length | about 32 ft |
| Location | 0.3 Mi N of Rd #305 |
| NBI structure number | 11C0092 |
| Condition class | Poor |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | August 2023 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | U: unknown foundation, not evaluated for scour |
Source: FHWA National Bridge Inventory, 2025 data as reported by the California department of transportation.
Busiest bridges in Glenn County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Interstate 5 over Glenn-colusa Drain Ditch | 1966 | 26,000 | Good |
| Interstate 5 over Logan Creek | 1970 | 25,500 | Good |
| Interstate 5 over North Fork Logan Creek | 1970 | 25,500 | Good |
| Interstate 5 SB over Central Irrigation Canal | 1966 | 13,000 | Good |
| Interstate 5 NB over Central Irrigation Canal | 1966 | 13,000 | Good |
| Interstate 5 SB over Cfnr Spur | 1966 | 13,000 | Good |
All bridges nearby: Glenn County, CA bridge conditions · every bridge in Glenn County · California bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.