Co Rd 424 over Iron River

Iron County, Michigan · rated Fair in the 2025 National Bridge Inventory

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

• Co Rd 424 over Iron River in Iron County, Michigan, is rated in fair condition in the 2025 National Bridge Inventory (as of August 20, 2026).
• Its lowest-rated component is the deck, rated 6 (satisfactory condition) on the 0-9 scale.
• It was built in 1929 and reconstructed in 1992, making it 96 years old at the 2025 inventory.
• It carries about 800 vehicles a day (traffic count year 1996).
• Its listed owner is a city or municipal highway agency.
• It is one of 26 of the 54 inventoried bridges in Iron County rated fair (48.1%); 12 (22.2%) are rated poor.
• Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
• Its class is unchanged from 2024 (fair), but component ratings moved: superstructure 7 to 6.
• Its most recent inspection on record is dated September 2024, on a 24-month routine inspection cycle.
• It is coded scour critical (NBI item 113 = 3): scour critical: foundations unstable for the assessed or calculated scour.
• 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 → (46.05837, -88.62687)

Component ratings

Bridge details

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

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