Bridge conditions in Charles Mix County, South Dakota
103 inventoried bridges · 24 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
About one in 4 bridges in Charles Mix County is rated in poor condition: 24 of 103 on the federal inventory, one of the higher shares in South Dakota.
- 24 of the 103 bridges in Charles Mix County, South Dakota, are rated in poor condition (23.3%) in the 2025 National Bridge Inventory, as of .
- 39 bridges (37.9%) are rated good and 40 (38.8%) fair.
- The median Charles Mix County bridge was built in 1970.
- The busiest poor-rated bridge is 30010 400TH Avenue over Choteau Creek (built 1958), carrying about 205 vehicles a day.
Good 37.9% · Fair 38.8% · Poor 23.3% of 103 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 |
|---|---|---|---|
| 30010 400TH Avenue over Choteau Creek | 1958 | 205 | Poor |
| 27720 363RD Avenue over Platte Creek | 1977 | 48 | Poor |
| 36460 276TH Street over Platte Creek | 1936 | 48 | Poor |
| 27180 369TH Avenue over Platte Creek | 1940 | 48 | Poor |
| 37570 287 Street over Pease Ck | 1920 | 48 | Poor |
| 37590 286TH Street over Pease Creek | 1974 | 48 | Poor |
| 38080 291ST Street over Creek | 1935 | 48 | Poor |
| 29470 381ST Avenue over Creek | 1979 | 48 | Poor |
| 38450 292ND Street over Creek | 1935 | 48 | Poor |
| 28870 385TH Avenue over Creek | 1945 | 48 | Poor |
| 38710 294TH Street over Creek | 1930 | 48 | Poor |
| 38890 286TH Street over Andes Creek | 1930 | 48 | Poor |
| 38930 302 St over Ck | 1941 | 48 | Poor |
| 30410 390 Ave over Mosquito Ck | 1941 | 48 | Poor |
| 30480 391ST Street over Mosquito Creek | 1974 | 48 | Poor |
| 39120 305TH Street over Mosquito Creek | 1920 | 48 | Poor |
| 29110 393RD Avenue over Creek | 1925 | 48 | Poor |
| 39460 289TH Street over Creek | 1940 | 48 | Poor |
| 39540 287TH Street over Choteau Creek | 1940 | 48 | Poor |
| 29620 396TH Avenue over Choteau Creek | 1930 | 48 | Poor |
| 39740 296TH Street over Creek | 1912 | 48 | Poor |
| 39450 292ND Street over Choteau Creek | 1974 | 40 | Poor |
| 294TH Street over Garden Ck | 1940 | 20 | Poor |
| 29120 383RD Avenue over Drainage Ditch | 1930 | 4 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| SD045 over Drainage Channel | 1994 | 3,934 | Good |
| SD044 over Platte Ck | 1964 | 2,420 | Fair |
| SD044 over Castalia Ck | 1963 | 1,538 | Good |
| Irr US018 over Saint Francis Bay | 2023 | 1,494 | Good |
| Irr SD050 over Trib Choteau Ck | 2020 | 1,329 | Good |
| Old Irr SD050 over Ck | 1940 | 1,329 | Fair |
| Irr US018 over Lake Andes Outlet | 2005 | 1,298 | Good |
| Irr US018 over Trib to Lake Andes | 2005 | 1,298 | Good |
| Irr SD046 over Ck | 1968 | 1,199 | Fair |
| Irr SD046 over Choteau Ck | 1968 | 1,199 | 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.