Structure A09347B0105 · Roberts County, SD
Carries IRR BIA RTE 121 over Big Spring Creek, 18.2 Km SW Of Sisseton.
A culvert 20 ft across. 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 | South Dakota |
| County | Roberts |
| Location | 18.2 Km SW Of Sisseton |
| Carries | IRR BIA RTE 121 |
| Crosses | Big Spring Creek |
| Coordinates | 45.49692, -97.04061 |
| Material | Concrete |
| Design | Culvert |
| Total Length | 20.3 ft (6.2 m) |
| Max Span | 20.3 ft (6.2 m) |
| Deck Width | 24.3 ft (7.4 m) |
| Deck Area | 45.9 sq m |
| Main Spans | 1 |
| Year Built | 2018 |
| Avg Daily Traffic | 75 (2024) |
| Truck Traffic | 5% |
| Lanes On Bridge | 2 |
| Last Inspection | April 2024 |
| Inspection Frequency | Every 24 months |
| Owner | Bureau of Indian Affairs |
| Historical Significance | Bridge is not eligible for the National Register |
| Scour Critical | 8 — Stable, low risk |
| Structure Number | 0000A09347B0105 |
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.