Structure S00556043+09761 · Flathead County, MT
Carries S 556-thompson R R over Mcgregor Creek, 18m SW Marion.
Set by its lowest-rated component: Deck and Superstructure and Substructure at 7 of 9.
How ratings work22 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 slab bridge.
| State | Montana |
| County | Flathead |
| Location | 18m SW Marion |
| Carries | S 556-thompson R R |
| Crosses | Mcgregor Creek |
| Coordinates | 48.02147, -114.99049 |
| Material | Prestressed Concrete |
| Design | Slab |
| Total Length | 22.0 ft (6.7 m) |
| Max Span | 21.0 ft (6.4 m) |
| Deck Width | 25.9 ft (7.9 m) |
| Deck Area | 52.9 sq m |
| Main Spans | 1 |
| Year Built | 1992 |
| Avg Daily Traffic | 61 (2023) |
| Lanes On Bridge | 2 |
| Last Inspection | July 2023 |
| Inspection Frequency | Every 24 months |
| Owner | County Highway Agency |
| Historical Significance | Bridge is not eligible for the National Register |
| Scour Critical | 5 — Stable for scour |
| Structure Number | S00556043+09761 |
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.