SD1804 over Oahe Reservoir Lk

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

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

• SD1804 over Oahe Reservoir Lk in Campbell 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 1980, making it 45 years old at the 2025 inventory.
• It carries about 147 vehicles a day (traffic count year 2024).
• Its listed owner is the state highway agency.
• It is one of 9 of the 16 inventoried bridges in Campbell County rated fair (56.2%); 0 (0.0%) 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 January 2025, on a 24-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 → (45.91348, -100.33067)

Component ratings

Bridge details

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

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