Checked
South Dakota Bridge Conditions
Highway bridges longer than 20 feet in the 2025 National Bridge Inventory
Yearly inspection ratings. A poor rating does not mean a bridge is unsafe to use.
- Highway bridges
- 5,883
- Good condition
- 34.6%
- 2,038
- Poor condition
- 16.1%
- 945
- Weight-limited or closed
- 944
Bridges by county
| County | Bridges | Good | Poor | Weight-limited | Avg. year built |
|---|---|---|---|---|---|
| Aurora County | 61 | 41% | 11.5% (7) | 8 | 1969 |
| Beadle County | 150 | 26% | 26.7% (40) | 39 | 1962 |
| Bennett County | 15 | 13.3% | 20% (3) | 5 | 1962 |
| Bon Homme County | 126 | 20.6% | 27% (34) | 30 | 1963 |
| Brookings County | 232 | 27.6% | 22.8% (53) | 46 | 1974 |
| Brown County | 170 | 32.4% | 11.8% (20) | 23 | 1983 |
| Brule County | 38 | 31.6% | 7.9% (3) | 3 | 1966 |
| Buffalo County | 25 | 32% | 4% (1) | 2 | 1976 |
| Butte County | 142 | 32.4% | 14.1% (20) | 17 | 1978 |
| Campbell County | 16 | 43.8% | 0% (0) | 1 | 1979 |
| Charles Mix County | 103 | 37.9% | 23.3% (24) | 23 | 1971 |
| Clark County | 21 | 52.4% | 4.8% (1) | 1 | 1989 |
| Clay County | 93 | 40.9% | 15.1% (14) | 5 | 1985 |
| Codington County | 75 | 20% | 18.7% (14) | 9 | 1976 |
| Corson County | 49 | 38.8% | 8.2% (4) | 3 | 1978 |
| Custer County | 94 | 50% | 5.3% (5) | 9 | 1977 |
| Davison County | 123 | 33.3% | 17.9% (22) | 13 | 1973 |
| Day County | 34 | 44.1% | 26.5% (9) | 8 | 1971 |
| Deuel County | 72 | 22.2% | 18.1% (13) | 11 | 1971 |
| Dewey County | 27 | 55.6% | 14.8% (4) | 6 | 1985 |
| Douglas County | 44 | 43.2% | 15.9% (7) | 11 | 1969 |
| Edmunds County | 20 | 35% | 25% (5) | 2 | 1991 |
| Fall River County | 80 | 51.3% | 6.3% (5) | 6 | 1982 |
| Faulk County | 46 | 17.4% | 23.9% (11) | 10 | 1966 |
| Grant County | 205 | 48.8% | 18.5% (38) | 40 | 1984 |
| Gregory County | 51 | 29.4% | 9.8% (5) | 8 | 1976 |
| Haakon County | 69 | 33.3% | 11.6% (8) | 9 | 1976 |
| Hamlin County | 61 | 42.6% | 11.5% (7) | 7 | 1979 |
| Hand County | 126 | 23% | 31.7% (40) | 34 | 1961 |
| Hanson County | 62 | 19.4% | 12.9% (8) | 2 | 1978 |
| Harding County | 49 | 51% | 2% (1) | 2 | 1985 |
| Hughes County | 40 | 42.5% | 20% (8) | 4 | 1980 |
| Hutchinson County | 160 | 31.3% | 15% (24) | 29 | 1974 |
| Hyde County | 23 | 34.8% | 21.7% (5) | 0 | 1974 |
| Jackson County | 89 | 29.2% | 14.6% (13) | 16 | 1969 |
| Jerauld County | 35 | 22.9% | 22.9% (8) | 3 | 1970 |
| Jones County | 37 | 16.2% | 5.4% (2) | 2 | 1965 |
| Kingsbury County | 35 | 17.1% | 28.6% (10) | 12 | 1964 |
| Lake County | 79 | 44.3% | 5.1% (4) | 4 | 1978 |
| Lawrence County | 136 | 39% | 11.8% (16) | 4 | 1982 |
| Lincoln County | 207 | 35.7% | 15.5% (32) | 32 | 1975 |
| Lyman County | 114 | 40.4% | 10.5% (12) | 12 | 1976 |
| Marshall County | 38 | 18.4% | 34.2% (13) | 11 | 1966 |
| McCook County | 98 | 44.9% | 7.1% (7) | 5 | 1978 |
| McPherson County | 14 | 28.6% | 0% (0) | 0 | 1978 |
| Meade County | 213 | 45.1% | 12.7% (27) | 24 | 1979 |
| Mellette County | 28 | 32.1% | 7.1% (2) | 0 | 1980 |
| Miner County | 63 | 30.2% | 30.2% (19) | 10 | 1974 |
| Minnehaha County | 394 | 41.4% | 9.1% (36) | 23 | 1986 |
| Moody County | 88 | 31.8% | 20.5% (18) | 12 | 1975 |
| Oglala Lakota County | 35 | 57.1% | 5.7% (2) | 1 | 1993 |
| Pennington County | 348 | 34.8% | 6% (21) | 30 | 1977 |
| Perkins County | 60 | 53.3% | 5% (3) | 6 | 1990 |
| Potter County | 24 | 37.5% | 0% (0) | 0 | 1981 |
| Roberts County | 158 | 25.9% | 25.3% (40) | 38 | 1972 |
| Sanborn County | 54 | 33.3% | 13% (7) | 12 | 1974 |
| Spink County | 176 | 13.1% | 30.1% (53) | 43 | 1960 |
| Stanley County | 37 | 35.1% | 16.2% (6) | 4 | 1969 |
| Sully County | 31 | 45.2% | 19.4% (6) | 1 | 1979 |
| Todd County | 27 | 44.4% | 25.9% (7) | 8 | 1991 |
| Tripp County | 89 | 32.6% | 24.7% (22) | 34 | 1977 |
| Turner County | 143 | 35.7% | 26.6% (38) | 25 | 1984 |
| Union County | 169 | 30.2% | 24.3% (41) | 36 | 1977 |
| Walworth County | 33 | 33.3% | 3% (1) | 4 | 1972 |
| Yankton County | 99 | 42.4% | 13.1% (13) | 24 | 1985 |
| Ziebach County | 30 | 23.3% | 10% (3) | 5 | 1969 |
Frequently asked questions
- How many bridges in South Dakota are in poor condition?
- In the 2025 National Bridge Inventory, 945 of 5,883 highway bridges in South Dakota were rated poor (16.1% of rated bridges).
- Which South Dakota counties have the most bridges in poor condition?
- Among counties with at least 30 bridges, the highest shares rated poor are Marshall County (34.2%), Hand County (31.7%), Miner County (30.2%), Spink County (30.1%), Kingsbury County (28.6%).
Source: Federal Highway Administration, National Bridge Inventory · 2025 data