US 191 over Yellowstone River

Sweet Grass County, Montana · rated Fair in the 2025 National Bridge Inventory

United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled August 20, 2026

• US 191 over Yellowstone River in Sweet Grass County, Montana, is rated in fair condition in the 2025 National Bridge Inventory (as of August 20, 2026).
• Its lowest-rated component is the substructure, rated 5 (fair condition) on the 0-9 scale.
• It was built in 1938, making it 87 years old at the 2025 inventory.
• It carries about 1,699 vehicles a day (traffic count year 2023).
• Its listed owner is the state highway agency.
• It is one of 58 of the 94 inventoried bridges in Sweet Grass County rated fair (61.7%); 6 (6.4%) are rated poor.
• A fair rating means the lowest-rated major component scores 5 or 6 on FHWA's 0-9 scale: some deterioration or minor section loss, but the structure is sound. It is the middle class, not a warning.

View this bridge on a map → (45.84685, -109.9399)

Component ratings

Bridge details

Source: FHWA National Bridge Inventory, 2025 data as reported by the Montana department of transportation.

Busiest bridges in Sweet Grass County

All bridges nearby: Sweet Grass County, MT bridge conditions · every bridge in Sweet Grass County · Montana bridges.

Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.