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County Road over Cub River;s.mapleton Br

Franklin County, Idaho · rated Fair in the 2025 National Bridge Inventory

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

County Road over Cub River;s.mapleton Br in Franklin County, Idaho, 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 1979, making it 46 years old at the 2025 inventory.
It carries about 50 vehicles a day (traffic count year 2023).
Its listed owner is the county highway agency.
It is one of 18 of the 23 inventoried bridges in Franklin County rated fair (78.3%); 2 (8.7%) 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.

Component ratings


Structure	Steel stringer or multi-beam girder
Length	about 26 ft
Location	1.7 S. 6.1 E. Preston
NBI structure number	000000000023320
Condition class	Fair

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

Bridge	Built	Vehicles/day	Condition
US 91 over Cub River	2006	8,600	Fair
US 91 over Bear River	2006	4,200	Fair
SH 36 over Bear River	2018	3,000	Good
SH 34 over Bear River;riverdale Br	1960	2,800	Fair
US 91 over West Cache Canal	1993	2,300	Good
SH 36 over Bear River	1960	1,300	Fair