Home › Montana › Fergus County › Forest Grove Rd over S Fork Mcdonald CR

Forest Grove Rd over S Fork Mcdonald CR

Fergus County, Montana · rated Good in the 2025 National Bridge Inventory

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

Forest Grove Rd over S Fork Mcdonald CR in Fergus County, Montana, is rated in good condition in the 2025 National Bridge Inventory (as of August 20, 2026).
Its lowest-rated component is the deck, rated 8 (very good condition) on the 0-9 scale.
It was built in 2021, making it 4 years old at the 2025 inventory.
It carries about 120 vehicles a day (traffic count year 2023).
Its listed owner is the county highway agency.
It is one of 52 of the 158 inventoried bridges in Fergus County rated good (32.9%); 9 (5.7%) are rated poor.
A good rating means every major component - deck, superstructure, substructure, or culvert - is rated 7 or higher on FHWA's 0-9 scale: no more than minor problems.

Component ratings


Structure	Prestressed concrete stringer or multi-beam girder
Length	about 64 ft
Location	6M SW Grassrange
NBI structure number	000000202102773
Condition class	Good

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

Bridge	Built	Vehicles/day	Condition
US 87-e Main St over Mill Ditch	1922	8,747	Fair
US 87-w Main St over Big Spring Creek	1962	5,357	Fair
US 191-1st Ave N over Big Spring Creek	1960	5,189	Fair
US 87 over Boyd Creek	1942	2,831	Fair
US 191-kendall Rd over Big Spring Creek	1976	2,663	Fair
US 87 over Beaver Creek	2009	2,589	Good