Bia 10 over Medicine Creek

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

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

• Bia 10 over Medicine Creek in Lyman 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 deck, rated 8 (very good condition) on the 0-9 scale.
• It was built in 2018, making it 7 years old at the 2025 inventory.
• It carries about 338 vehicles a day (traffic count year 2024).
• It is one of 46 of the 114 inventoried bridges in Lyman County rated good (40.4%); 12 (10.5%) are rated poor.
• Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
• Its class is unchanged from 2024 (good), but component ratings moved: deck 9 to 8, substructure 9 to 8.
• Its most recent inspection on record is dated August 2024, on a 24-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 → (44.08772, -99.72035)

Component ratings

Bridge details

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

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