Scour Critical Bridges in South Dakota
207 bridges in South Dakota at risk from water erosion around foundations.
Scour Critical Bridges
Scour is the erosion of soil and rock around a bridge's foundation caused by moving water. When foundations are exposed or undermined, a bridge can collapse even if its deck and superstructure are in good condition. Scour is the leading cause of bridge failures in the US. These 207 bridges in South Dakota have been identified as vulnerable to scour damage.
| Bridge | State | Scour Status | Condition | Year Built | ADT |
|---|---|---|---|---|---|
| JAMES RIVER | South Dakota | Scour Critical — Unaddressed | Fair | 1952 | 2,250 |
| SAND CREEK | South Dakota | Scour Critical — Unaddressed | Fair | 1900 | 156 |
| MIDDLE PEARL CREEK | South Dakota | Scour Critical — Unaddressed | Poor | 1928 | 56 |
| WOUNDED KNEE CREEK | South Dakota | Scour Critical — Countermeasures Ineffective | Good | 2007 | 600 |
| MEADE ST. DRAINAGE | South Dakota | Scour Critical — Countermeasures Installed | Good | 1964 | 15,500 |
| CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1961 | 8,815 |
| CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1961 | 8,815 |
| LONE ROCK CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1959 | 7,955 |
| LONE ROCK CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1959 | 7,955 |
| BAD RV | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1956 | 6,040 |
| SPRING CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1963 | 4,913 |
| SPRING CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1963 | 4,913 |
| SPLIT ROCK CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1963 | 4,101 |
| SKUNK CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1986 | 4,068 |
| BULL CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1964 | 4,065 |
| BULL CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1964 | 4,065 |
| JAMES RV | South Dakota | Scour Critical — Countermeasures Installed | Poor | 1960 | 3,601 |
| BEAVER CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1963 | 3,042 |
| NINE MILE CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1963 | 3,042 |
| ELM RV | South Dakota | Scour Critical — Countermeasures Installed | Poor | 1959 | 3,041 |
| CAIN CREEK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1935 | 2,600 |
| DEER CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1967 | 2,585 |
| BIG SIOUX RIVER | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1939 | 2,500 |
| JAMES RV | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1988 | 2,445 |
| CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1988 | 2,420 |
| BIG SIOUX RIVER | South Dakota | Scour Critical — Countermeasures Installed | Poor | 1966 | 2,419 |
| WEST FORK VERMILLION RV | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1976 | 2,416 |
| SNAKE CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1978 | 2,141 |
| PIPESTONE CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1963 | 1,968 |
| SOUTH MEDICINE CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1951 | 1,914 |
| LAKE NORDEN OUTLET | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1949 | 1,862 |
| BIG SIOUX RIVER | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1977 | 1,831 |
| EAST FORK VERMILLION RV | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1947 | 1,768 |
| BELLE FOURCHE RV | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1985 | 1,670 |
| PONY CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1959 | 1,657 |
| PONY CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1959 | 1,657 |
| JAMES RV | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1962 | 1,651 |
| NORTH BR DRY CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1964 | 1,651 |
| WOLF CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1962 | 1,651 |
| EAST FORK VERMILLION RV | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1989 | 1,648 |
| DRY RUN CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1955 | 1,578 |
| GRACE COOLIDGE CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1977 | 1,562 |
| CROW CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1966 | 1,543 |
| ANDES CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1957 | 1,516 |
| CROW CK | South Dakota | Scour Critical — Countermeasures Installed | Poor | 1940 | 1,500 |
| CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1982 | 1,425 |
| SLIP-UP CREEK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1970 | 1,381 |
| BIG SIOUX RV | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1951 | 1,371 |
| BUFFALO CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1964 | 1,330 |
| SLIM BUTTE CK | South Dakota | Scour Critical — Countermeasures Installed | Fair | 1953 | 1,294 |
Scour Critical Rating Codes
| Code 2 — Unaddressed | Bridge is scour critical with no countermeasures installed. The foundation is vulnerable and no protective action has been taken. |
| Code 3 — Countermeasures Installed | Protective measures (riprap, sheet piling, etc.) have been installed to reduce scour risk, but the bridge remains classified as scour critical. |
| Code 6 — Countermeasures Ineffective | Protective measures were installed but have been assessed as ineffective. The bridge requires re-evaluation and additional action. |
About Scour Critical Bridges
Scour critical bridges have been identified through underwater inspection or analysis as having foundations that are unstable or could become unstable during flood conditions. FHWA requires action plans for all scour critical bridges. Famous scour failures include the 1987 Schoharie Creek Bridge collapse in New York.