18n03 over South Fork Stony Creek
Colusa County, California · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- 18n03 over South Fork Stony Creek in Colusa County, California, 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 1975, making it 50 years old at the 2025 inventory.
- It carries about 150 vehicles a day (traffic count year 1992).
- It is one of 101 of the 213 inventoried bridges in Colusa County rated good (47.4%); 12 (5.6%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- It does not appear under this structure number in the 2024 inventory (a new or renumbered structure).
- Its most recent inspection on record is dated August 2023, on a 24-month routine inspection cycle.
- 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 → (39.39613, -122.64396)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 7 | Good condition |
| Superstructure | 7 | Good condition |
| Substructure | 7 | Good condition |
Bridge details
| Structure | Steel stringer or multi-beam girder |
| Length | about 57 ft |
| Location | 0.3 Mi. N. of Jct. 18n01 |
| NBI structure number | 050853000001004 |
| Condition class | Good |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | August 2023 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 5: foundations stable, scour within the limits of the footing or piles |
Source: FHWA National Bridge Inventory, 2025 data as reported by the California department of transportation.
Busiest bridges in Colusa County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Interstate 5 over Hillgate Road | 1957 | 35,000 | Good |
| Interstate 5 over Brush Creek | 1967 | 35,000 | Good |
| Interstate 5 over Cortina Creek Overflow | 1946 | 33,000 | Good |
| Interstate 5 over Farm Land Drain | 1968 | 30,000 | Fair |
| Interstate 5 over South Branch Sand Creek | 1967 | 29,500 | Good |
| Interstate 5 over Petroleum Creek | 1967 | 18,000 | Fair |
All bridges nearby: Colusa County, CA bridge conditions · every bridge in Colusa County · California bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.