SMA3340;MCDERMMOTT over Ridenbaugh High Line Cnl

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

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

• SMA3340;MCDERMMOTT over Ridenbaugh High Line Cnl in Canyon County, Idaho, is rated in fair condition in the 2025 National Bridge Inventory (as of August 20, 2026).
• Its lowest-rated component is the culvert, rated 6 (satisfactory condition) on the 0-9 scale.
• It was built in 1987, making it 38 years old at the 2025 inventory.
• It carries about 300 vehicles a day (traffic count year 2023).
• It is one of 199 of the 291 inventoried bridges in Canyon County rated fair (68.4%); 6 (2.1%) 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 → (43.52056, -116.47361)

Component ratings

Bridge details

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

Busiest bridges in Canyon County

All bridges nearby: Canyon County, ID bridge conditions · every bridge in Canyon County · Idaho bridges.

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