Nfa 1921 (sa 9420) over South Harpeth River

Williamson County, Tennessee · rated Good in the 2025 National Bridge Inventory

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

• Nfa 1921 (sa 9420) over South Harpeth River in Williamson County, Tennessee, is rated in good condition in the 2025 National Bridge Inventory (as of August 20, 2026).
• Its lowest-rated component is the deck, rated 7 (good condition) on the 0-9 scale.
• It was built in 1985, making it 40 years old at the 2025 inventory.
• It carries about 703 vehicles a day (traffic count year 2021).
• Its listed owner is the county highway agency.
• It is one of 341 of the 531 inventoried bridges in Williamson County rated good (64.2%); 16 (3.0%) 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.

View this bridge on a map → (35.97497, -87.06178)

Component ratings

Bridge details

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

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