Structure 11663-00255 · Siskiyou County, CA
Carries Auto Tour Road over Canal Turnout, SW Corner Unit 4a.
A culvert 22 ft across with 4 openings. Lengths are drawn to scale; at this length a semi-truck would be a speck. Each part is colored by its latest inspection rating. The inventory records lengths but not heights, so those are drawn as typical for a culvert.
| State | California |
| County | Siskiyou |
| Location | SW Corner Unit 4a |
| Carries | Auto Tour Road |
| Crosses | Canal Turnout |
| Coordinates | 41.97600, -121.71350 |
| Material | Steel |
| Design | Culvert |
| Total Length | 22.0 ft (6.7 m) |
| Max Span | 3.9 ft (1.2 m) |
| Deck Width | 25.9 ft (7.9 m) |
| Deck Area | 52.9 sq m |
| Main Spans | 4 |
| Year Built | 1963 (reconstructed 1970) |
| Avg Daily Traffic | 50 (2022) |
| Lanes On Bridge | 2 |
| Last Inspection | October 2022 |
| Inspection Frequency | Every 24 months |
| Owner | Code 63 |
| Historical Significance | Bridge is not eligible for the National Register |
| Scour Critical | 5 — Stable for scour |
| Structure Number | 000011663-00255 |
Inspectors rate each major part of a bridge (the deck you drive on, the superstructure of beams that holds it up, and the substructure of piers and abutments beneath) on a 0–9 scale. A bridge's overall condition is its lowest of those ratings, so one deteriorated component makes the whole bridge "poor."
A poor rating is not a closure. It means the bridge is flagged for priority repair or replacement; bridges judged unsafe are closed or posted with weight limits. The waterway (channel) rating is reported, but it does not count toward the overall classification.