Structure L56506000+05001 · Yellowstone County, MT
Carries 56th ST W over Big Ditch 071, 3m W Billings.
24 ft end to end. 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 or the layout of the shorter spans, so those are drawn as typical for a tee-beam bridge.
| State | Montana |
| County | Yellowstone |
| Location | 3m W Billings |
| Carries | 56th ST W |
| Crosses | Big Ditch 071 |
| Coordinates | 45.77621, -108.65921 |
| Material | Prestressed Concrete |
| Design | Tee Beam |
| Total Length | 24.0 ft (7.3 m) |
| Max Span | 23.0 ft (7 m) |
| Deck Width | 25.9 ft (7.9 m) |
| Deck Area | 57.7 sq m |
| Main Spans | 1 |
| Year Built | 1964 |
| Avg Daily Traffic | 2,799 (2023) |
| Truck Traffic | 3% |
| Lanes On Bridge | 2 |
| Last Inspection | December 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 | L56506000+05001 |
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.