No Data Entered over Boulder Creek
Siskiyou County, California · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- No Data Entered over Boulder Creek in Siskiyou County, California, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 1 (imminent failure condition) on the 0-9 scale.
- It was built in 1967, making it 58 years old at the 2025 inventory.
- It carries about 2 vehicles a day.
- It is one of 25 of the 425 inventoried bridges in Siskiyou County rated poor (5.9%); 25 (5.9%) are rated poor.
- Its traffic status in the 2025 inventory is closed to all traffic (NBI item 41).
- It was rated fair in the 2024 inventory and is now poor (deck 6 to 5, substructure 7 to 1).
- Status change: newly closed since 2024.
- Its most recent inspection on record is dated September 2024, on a 12-month routine inspection cycle.
- It is coded scour critical (NBI item 113 = 1): scour critical: field review indicates failure of piers or abutments is imminent.
- It has fracture-critical members (NBI item 92A): steel tension members without a redundant load path, which get their own scheduled inspections.
- 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 → (41.26667, -122.82315)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 5 | Fair condition |
| Superstructure | 5 | 5 | Fair condition |
| Substructure | 7 | 1 | Imminent failure condition |
Bridge details
| Structure | Steel through truss |
| Length | about 80 ft |
| Location | Callahan |
| NBI structure number | 050555000001081 |
| Condition class | Poor |
| Traffic status (item 41) | Closed to all traffic |
| Last inspection (item 90) | September 2024 |
| Inspection interval (item 91) | 12 months |
| Scour (item 113) | 1: scour critical: field review indicates failure of piers or abutments is imminent |
| Fracture critical (item 92A) | Yes |
Source: FHWA National Bridge Inventory, 2025 data as reported by the California department of transportation.
Busiest bridges in Siskiyou County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Interstate 5 SB over UP RR & Amtrak | 1964 | 20,000 | Fair |
| Interstate 5 NB over UP RR & Amtrak | 1964 | 20,000 | Fair |
| Interstate 5 over Mott Road | 1976 | 20,000 | Good |
| Interstate 5 over Mott Road | 1976 | 20,000 | Fair |
| Interstate 5 over Dunsmuir Ave | 1976 | 19,200 | Good |
| Interstate 5 over Sacramento UP RR Amtrak | 1955 | 18,000 | Good |
All bridges nearby: Siskiyou County, CA bridge conditions · every bridge in Siskiyou County · California bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.