Bridge conditions in Pennington County, South Dakota
348 inventoried bridges · 21 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
The federal inventory lists 348 bridges in Pennington County: 121 rated good, 206 fair, and 21 poor.
- 21 of the 348 bridges in Pennington County, South Dakota, are rated in poor condition (6.0%) in the 2025 National Bridge Inventory, as of .
- 121 bridges (34.8%) are rated good and 206 (59.2%) fair.
- The median Pennington County bridge was built in 1973.
- The busiest poor-rated bridge is Chapel Lane over Rapid Ck (built 1974), carrying about 4,700 vehicles a day.
Good 34.8% · Fair 59.2% · Poor 6.0% of 348 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 |
|---|---|---|---|
| Chapel Lane over Rapid Ck | 1974 | 4,700 | Poor |
| US385 over Horse Ck | 1947 | 2,378 | Poor |
| Country Road over Box Elder Ck | 1950 | 1,214 | Poor |
| Town Street (US16) over Abandon Line RR | 1930 | 1,000 | Poor |
| Bennet Road over Box Elder Ck | 1973 | 881 | Poor |
| Elm Avenue over Drainage Ditch | 1984 | 300 | Poor |
| Summerset Drive over Ditch | 1984 | 250 | Poor |
| Thunderhead Falls over Rapid Ck | 1972 | 218 | Poor |
| Thunderhead Falls over Rapid Ck | 1972 | 218 | Poor |
| Roy Street over Grizzly Bear Ck | 1955 | 200 | Poor |
| Tomahawk Dr over Drainage Channel | 1977 | 125 | Poor |
| Creek Drive over Drainage Ditch | 1985 | 100 | Poor |
| Slate Prairie Road over Castle Ck | 1950 | 73 | Poor |
| Thunderhead Falls over Rapid Ck | 1972 | 62 | Poor |
| Hammerquist Road over Rapid Ck | 1916 | 54 | Poor |
| 159TH Ave over Boxelder Ck | 1950 | 39 | Poor |
| Idlehurst Lane over Rapid Ck | 1972 | 25 | Poor |
| Paulsen Rd over Cottonwood Ck | 1959 | 25 | Poor |
| 223RD Street over Trib to Cheyenne River | 1935 | 20 | Poor |
| 234TH Street over Trib to Rapid Ck | 1930 | 15 | Poor |
| McCURDY GULCH over Rapid Creek | 1945 | 10 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I090 over Boxelder Ck | 1994 | 26,980 | Good |
| Cambell St over Ck | 1964 | 23,179 | Fair |
| SD079NF over St Joseph St Rcp&e RR | 1964 | 23,179 | Fair |
| Cambell St over Rapid Ck | 1967 | 21,415 | Fair |
| West Main St. over Rapid Ck | 1975 | 20,745 | Good |
| SD231 over Rapid Ck | 1974 | 20,057 | Fair |
| I090 W over Haines Ave | 2001 | 19,785 | Good |
| I090 E over Haines Ave | 2000 | 19,785 | Good |
| I090 W over Maple Ave | 1959 | 19,785 | Fair |
| I090 E over Maple Ave | 1959 | 19,785 | Fair |
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.