Structure 39C0285 · Merced County, CA
Carries Dan Mcnamara Road over Duck Slough, 1.5 Mi N Sandy Mush Road.
A culvert 21 ft across with 3 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 | Merced |
| Location | 1.5 Mi N Sandy Mush Road |
| Carries | Dan Mcnamara Road |
| Crosses | Duck Slough |
| Coordinates | 37.20795, -120.67065 |
| Material | Steel |
| Design | Culvert |
| Total Length | 21.0 ft (6.4 m) |
| Max Span | 6.9 ft (2.1 m) |
| Deck Area | 48 sq m |
| Main Spans | 3 |
| Year Built | 1982 |
| Avg Daily Traffic | 75 (1990) |
| Truck Traffic | 3% |
| 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 | 39C0285 |
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.