Irr SD1806 over La Roche Ck

Stanley County, South Dakota · rated Fair in the 2025 National Bridge Inventory

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

• Irr SD1806 over La Roche Ck in Stanley County, South Dakota, 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 2007, making it 18 years old at the 2025 inventory.
• It carries about 279 vehicles a day (traffic count year 2024).
• Its listed owner is the state highway agency.
• It is one of 18 of the 37 inventoried bridges in Stanley County rated fair (48.6%); 6 (16.2%) 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 November 2023, on a 48-month routine inspection cycle.
• 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 → (44.23193, -99.93058)

Component ratings

Bridge details

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

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