30520 475TH Ave over Ck

Union County, South Dakota · rated Good in the 2025 National Bridge Inventory

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

• 30520 475TH Ave over Ck in Union County, South Dakota, is rated in good condition in the 2025 National Bridge Inventory (as of August 20, 2026).
• Its lowest-rated component is the culvert, rated 8 (very good condition) on the 0-9 scale.
• It was built in 2009, making it 16 years old at the 2025 inventory.
• It carries about 150 vehicles a day (traffic count year 2022).
• Its listed owner is the county highway agency.
• It is one of 51 of the 169 inventoried bridges in Union County rated good (30.2%); 41 (24.3%) are rated poor.
• Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
• Its condition class and component ratings are unchanged from the 2024 inventory.
• Its most recent inspection on record is dated June 2022, on a 48-month routine inspection cycle.
• 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 → (42.96492, -96.70686)

Component ratings

Bridge details

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

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