Scour Critical Bridges in Iowa
392 bridges in Iowa 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 392 bridges in Iowa have been identified as vulnerable to scour damage.
| Bridge | State | Scour Status | Condition | Year Built | ADT |
|---|---|---|---|---|---|
| BR MUD CK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1900 | 20 |
| PRAIRIE CREEK | Iowa | Scour Critical — Countermeasures Installed | Fair | 1996 | 20 |
| CHEQUEST CREEK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1953 | 20 |
| SMALL STREAM | Iowa | Scour Critical — Countermeasures Installed | Fair | 1900 | 20 |
| MUD CREEK | Iowa | Scour Critical — Countermeasures Installed | Fair | 1981 | 20 |
| TRIB TO MASON CREEK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1957 | 20 |
| STREAM | Iowa | Scour Critical — Countermeasures Installed | Poor | 1970 | 20 |
| SMALL STREAM | Iowa | Scour Critical — Countermeasures Installed | Fair | 1960 | 20 |
| WRIGHT CREEK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1900 | 20 |
| INDIAN CREEK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1914 | 20 |
| LITTLE SUGAR CREEK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1900 | 20 |
| DAVISONS CREEK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1978 | 20 |
| WAUBONSIE CR | Iowa | Scour Critical — Countermeasures Installed | Poor | 1940 | 20 |
| BRUSH CREEK | Iowa | Scour Critical — Countermeasures Installed | Good | 2019 | 20 |
| W TARKIO RIVER | Iowa | Scour Critical — Countermeasures Installed | Poor | 1972 | 20 |
| STREAM | Iowa | Scour Critical — Countermeasures Installed | Poor | 1984 | 20 |
| STREAM | Iowa | Scour Critical — Countermeasures Installed | Fair | 1992 | 20 |
| GOOSEBERRY CREEK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1965 | 20 |
| PARNELL CREEK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1935 | 20 |
| SMALL STREAM | Iowa | Scour Critical — Countermeasures Installed | Fair | 1900 | 16 |
| EAST FORK CROOKED CREEK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1914 | 16 |
| BRANCH OF SUGAR CREEK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1940 | 16 |
| BRUSH CREEK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1917 | 16 |
| SMALL STREAM | Iowa | Scour Critical — Countermeasures Installed | Poor | 1918 | 15 |
| STREAM | Iowa | Scour Critical — Countermeasures Installed | Fair | 1961 | 15 |
| CREEK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1972 | 15 |
| BRANCH MIDDLE RIVER | Iowa | Scour Critical — Countermeasures Installed | Poor | 1948 | 15 |
| STREAM | Iowa | Scour Critical — Countermeasures Installed | Poor | 1979 | 15 |
| STREAM | Iowa | Scour Critical — Countermeasures Installed | Poor | 1958 | 15 |
| STREAM | Iowa | Scour Critical — Countermeasures Installed | Poor | 1950 | 15 |
| STEIN CK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1948 | 15 |
| BRUSHY FORK CREEK | Iowa | Scour Critical — Countermeasures Installed | Fair | 1951 | 15 |
| WATERWAY | Iowa | Scour Critical — Countermeasures Installed | Poor | 1900 | 15 |
| ROCK CR | Iowa | Scour Critical — Countermeasures Installed | Poor | 1917 | 15 |
| SPRING BRANCH CREEK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1981 | 15 |
| SMALL CREEK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1972 | 15 |
| WHITE FOX CREEK | Iowa | Scour Critical — Countermeasures Installed | Fair | 1983 | 15 |
| STREAM | Iowa | Scour Critical — Countermeasures Installed | Poor | 1938 | 15 |
| BUFFALO CREEK | Iowa | Scour Critical — Countermeasures Installed | Fair | 1991 | 15 |
| BOYER RIVER | Iowa | Scour Critical — Countermeasures Installed | Poor | 1980 | 15 |
| SMALL CREEK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1949 | 15 |
| CREEK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1977 | 15 |
| EMERY CREEK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1900 | 15 |
| SMALL STREAM | Iowa | Scour Critical — Countermeasures Installed | Fair | 1900 | 15 |
| DEER CREEK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1940 | 15 |
| HUNTER BRANCH | Iowa | Scour Critical — Countermeasures Installed | Poor | 1950 | 15 |
| DRAINAGE | Iowa | Scour Critical — Countermeasures Installed | Fair | 1940 | 15 |
| STREAM | Iowa | Scour Critical — Countermeasures Installed | Poor | 1979 | 15 |
| STONY CREEK | Iowa | Scour Critical — Countermeasures Installed | Poor | 1971 | 15 |
| E FK GRAND RIVER | Iowa | Scour Critical — Countermeasures Installed | Poor | 1970 | 15 |
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.