Bridge conditions in Custer County, South Dakota
94 inventoried bridges · 5 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
5 of the 94 bridges the federal inventory lists in Custer County are rated poor; the rest split 47 good and 42 fair.
- 5 of the 94 bridges in Custer County, South Dakota, are rated in poor condition (5.3%) in the 2025 National Bridge Inventory, as of .
- 47 bridges (50.0%) are rated good and 42 (44.7%) fair.
- The median Custer County bridge was built in 1974.
- The busiest poor-rated bridge is State Park Rd over Center Lake Inlet (built 1950), carrying about 1,000 vehicles a day.
Good 50.0% · Fair 44.7% · Poor 5.3% of 94 bridges
Bridges rated poor
Every bridge in the county with a poor rating, busiest first. Poor means a major component is rated 4 or lower on FHWA's 0-9 scale; it is a repair flag, not a closure notice.
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| State Park Rd over Center Lake Inlet | 1950 | 1,000 | Poor |
| E Main St Fas 6488 over Beaver Ck | 1971 | 108 | Poor |
| State Park Rd over Grace Coolidge Creek | 1950 | 100 | Poor |
| State Park Rd over Grace Coolidge Creek | 1950 | 100 | Poor |
| State Park Rd over Ck | 1950 | 5 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US016 over French Ck | 1966 | 10,052 | Fair |
| US016 over Ck | 1966 | 10,052 | Good |
| US016A over Laughing Water Ck | 1964 | 6,829 | Good |
| SD079 over Battle Ck | 1997 | 6,610 | Good |
| US016 over French Ck | 1974 | 3,709 | Fair |
| US016 over French Ck | 1974 | 3,709 | Fair |
| SD079 over Dry Ck | 2004 | 3,672 | Good |
| SD079 over Dry Ck | 2004 | 3,672 | Fair |
| SD079 over Ck | 1957 | 3,672 | Fair |
| SD079 over Lame Johnny Ck | 2004 | 3,672 | Good |
Source: FHWA National Bridge Inventory, 2025. Counts cover inventoried highway bridges over 20 feet; ratings are reported by the state DOT.
All of South Dakota: South Dakota bridge conditions by county · every download on the data page.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.