Structure 18070198 · Davison County, SD
Carries 401st Avenue over North Br Twelve Mile Ck, 10 W & 1.2 N Ethan.
A culvert 32 ft across with 3 openings. Lengths and the car on the deck are drawn to the same scale. 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 | South Dakota |
| County | Davison |
| Location | 10 W & 1.2 N Ethan |
| Carries | 401st Avenue |
| Crosses | North Br Twelve Mile Ck |
| Coordinates | 43.55727, -98.18496 |
| Material | Concrete |
| Design | Culvert |
| Total Length | 32.2 ft (9.8 m) |
| Max Span | 14.1 ft (4.3 m) |
| Deck Width | 31.2 ft (9.5 m) |
| Deck Area | 93.1 sq m |
| Main Spans | 3 |
| Year Built | 1925 (reconstructed 1965) |
| Avg Daily Traffic | 53 (2022) |
| Truck Traffic | 2% |
| Lanes On Bridge | 2 |
| Last Inspection | July 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 | 000000018070198 |
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.