Structure 12C0401 · Butte County, CA
Carries Nelson RD over Durham Slough, 4.6 Mi W Midway RD.
A culvert 23 ft across with 2 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 | Butte |
| Location | 4.6 Mi W Midway RD |
| Carries | Nelson RD |
| Crosses | Durham Slough |
| Coordinates | 39.55157, -121.84828 |
| Material | Concrete Continuous |
| Design | Culvert |
| Total Length | 23.0 ft (7 m) |
| Max Span | 11.2 ft (3.4 m) |
| Deck Width | 27.2 ft (8.3 m) |
| Deck Area | 58.1 sq m |
| Main Spans | 2 |
| Year Built | 1938 |
| Avg Daily Traffic | 88 (2019) |
| Truck Traffic | 28% |
| Lanes On Bridge | 2 |
| Last Inspection | November 2024 |
| Inspection Frequency | Every 24 months |
| Owner | County Highway Agency |
| Historical Significance | Bridge is not eligible for the National Register |
| Scour Critical | 8 — Stable, low risk |
| Structure Number | 12C0401 |
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.