Scour Critical Bridges
23,522 bridges across the US 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 23,522 bridges have been identified as vulnerable to scour damage.
| Bridge | State | Scour Status | Condition | Year Built | ADT |
|---|---|---|---|---|---|
| PAULINS KILL | New Jersey | Scour Critical — Countermeasures Installed | Good | 1931 | 5,501 |
| FARM RIVER | Connecticut | Scour Critical — Countermeasures Installed | Fair | 1900 | 5,500 |
| GILDER CREEK | South Carolina | Scour Critical — Countermeasures Installed | Good | 1970 | 5,500 |
| BRUSHY CREEK | South Carolina | Scour Critical — Countermeasures Installed | Fair | 1987 | 5,500 |
| BR. LITTLE CONTENTNEA CR | North Carolina | Scour Critical — Countermeasures Installed | Fair | 1956 | 5,500 |
| MUD CREEK | Wisconsin | Scour Critical — Countermeasures Installed | Fair | 1932 | 5,500 |
| MAGINA CREEK | Puerto Rico | Scour Critical — Countermeasures Installed | Fair | 1969 | 5,500 |
| BOISE RIVER | Idaho | Scour Critical — Countermeasures Installed | Fair | 1932 | 5,500 |
| BOISE RIVER | Idaho | Scour Critical — Countermeasures Installed | Fair | 1976 | 5,500 |
| TEN MILE RIVER | Connecticut | Scour Critical — Countermeasures Installed | Fair | 1936 | 5,500 |
| Branch of HONEY CREEK | Indiana | Scour Critical — Countermeasures Installed | Fair | 1919 | 5,500 |
| WATER BENT TRAVERS POND | Massachusetts | Scour Critical — Countermeasures Installed | Fair | 1924 | 5,500 |
| BIG SALT WASH | Colorado | Scour Critical — Countermeasures Installed | Fair | 1970 | 5,500 |
| BIG SALT WASH | Colorado | Scour Critical — Countermeasures Installed | Fair | 1970 | 5,500 |
| LITTLE SALT WASH | Colorado | Scour Critical — Countermeasures Installed | Fair | 1970 | 5,500 |
| LITTLE SALT WASH | Colorado | Scour Critical — Countermeasures Installed | Fair | 1970 | 5,500 |
| MORTON HALL DITCH | Indiana | Scour Critical — Countermeasures Installed | Fair | 1996 | 5,493 |
| FISH CREEK | Michigan | Scour Critical — Countermeasures Installed | Fair | 1931 | 5,487 |
| BUTTERNUT CREEK | Michigan | Scour Critical — Countermeasures Installed | Fair | 1940 | 5,487 |
| PRAIRIE CREEK | Michigan | Scour Critical — Countermeasures Installed | Fair | 1953 | 5,487 |
| PUSHAPATAPA CR | Louisiana | Scour Critical — Countermeasures Installed | Good | 1965 | 5,485 |
| DRAIN | Louisiana | Scour Critical — Countermeasures Installed | Fair | 1965 | 5,485 |
| DRAW | Texas | Scour Critical — Countermeasures Installed | Fair | 1949 | 5,482 |
| TYLER DITCH | Indiana | Scour Critical — Countermeasures Installed | Fair | 1961 | 5,472 |
| JAMES KRUCEK DITCH | Indiana | Scour Critical — Countermeasures Installed | Fair | 1961 | 5,472 |
| Ash Swale | Oregon | Scour Critical — Countermeasures Installed | Fair | 1922 | 5,468 |
| ST MARYS RIVER OVERFLOW | Indiana | Scour Critical — Countermeasures Installed | Fair | 1997 | 5,462 |
| SEVENTEEN MILE CREEK | Indiana | Scour Critical — Countermeasures Installed | Good | 1997 | 5,462 |
| BLACK RIVER | Michigan | Scour Critical — Countermeasures Installed | Poor | 1947 | 5,462 |
| Cottonwood Wash | Arizona | Scour Critical — Countermeasures Installed | Fair | 1948 | 5,460 |
| CLARKS RR PEMIGEWASSET R | New Hampshire | Scour Critical — Countermeasures Installed | Good | 1981 | 5,456 |
| PETERS BROOK | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1901 | 5,455 |
| DECKER CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Poor | 1950 | 5,455 |
| SOUTH MAYDE CREEK | Texas | Scour Critical — Countermeasures Installed | Fair | 1968 | 5,450 |
| S Yamhill River | Oregon | Scour Critical — Countermeasures Installed | Fair | 1935 | 5,448 |
| HICKMAN LATERAL DITCH | Indiana | Scour Critical — Countermeasures Installed | Fair | 1992 | 5,445 |
| FOX SKIN BAYOU | Louisiana | Scour Critical — Countermeasures Installed | Poor | 1979 | 5,436 |
| SCHOENECK CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Poor | 1942 | 5,435 |
| WESTERN CREEK | Indiana | Scour Critical — Countermeasures Installed | Fair | 1932 | 5,417 |
| BRANCH | Tennessee | Scour Critical — Countermeasures Installed | Fair | 1925 | 5,411 |
| SILVER CREEK | Texas | Scour Critical — Countermeasures Installed | Good | 1997 | 5,408 |
| BIRD CREEK | Tennessee | Scour Critical — Countermeasures Installed | Good | 1959 | 5,400 |
| PRATT CREEK | Wisconsin | Scour Critical — Countermeasures Installed | Fair | 1964 | 5,400 |
| DOCTOR PASS INLET | Florida | Scour Critical — Countermeasures Installed | Good | 1975 | 5,400 |
| WHITING RIVER | Connecticut | Scour Critical — Countermeasures Installed | Fair | 1949 | 5,400 |
| LITTLE CALUMET RIVER | Indiana | Scour Critical — Countermeasures Installed | Fair | 1972 | 5,400 |
| SIMMONS CREEK | South Carolina | Scour Critical — Countermeasures Installed | Fair | 1967 | 5,400 |
| PRAIRIE RIVER | Michigan | Scour Critical — Countermeasures Installed | Fair | 1931 | 5,400 |
| MORGAN BROOK | Connecticut | Scour Critical — Countermeasures Installed | Fair | 1947 | 5,400 |
| BRANCH BUSSERON CREEK | Indiana | Scour Critical — Countermeasures Installed | Fair | 1965 | 5,399 |
Scour Critical Bridges by State
States ranked by number of scour critical bridges.
| State | Scour Critical | Unaddressed | Countermeasures | Ineffective |
|---|---|---|---|---|
| Texas | 3,912 | 75 | 516 | 3,321 |
| Pennsylvania | 2,233 | 45 | 2,187 | 1 |
| Louisiana | 1,302 | 13 | 1,288 | 1 |
| South Carolina | 1,263 | 0 | 1,217 | 46 |
| Oregon | 1,231 | 4 | 1,221 | 6 |
| Michigan | 1,081 | 14 | 1,062 | 5 |
| Nebraska | 962 | 224 | 732 | 6 |
| New York | 864 | 9 | 780 | 75 |
| Indiana | 756 | 7 | 749 | 0 |
| Wisconsin | 751 | 0 | 748 | 3 |
| Kansas | 638 | 9 | 626 | 3 |
| California | 623 | 27 | 562 | 34 |
| Tennessee | 581 | 12 | 569 | 0 |
| Washington | 516 | 14 | 487 | 15 |
| Puerto Rico | 496 | 9 | 487 | 0 |
| Alabama | 450 | 1 | 423 | 26 |
| Iowa | 392 | 3 | 385 | 4 |
| New Jersey | 362 | 2 | 360 | 0 |
| Florida | 357 | 4 | 339 | 14 |
| Oklahoma | 317 | 33 | 283 | 1 |
| Missouri | 312 | 4 | 307 | 1 |
| Mississippi | 301 | 6 | 286 | 9 |
| Connecticut | 279 | 0 | 276 | 3 |
| Minnesota | 257 | 38 | 202 | 17 |
| Vermont | 242 | 0 | 240 | 2 |
| Colorado | 241 | 3 | 238 | 0 |
| Idaho | 215 | 18 | 186 | 11 |
| South Dakota | 207 | 3 | 203 | 1 |
| Arkansas | 187 | 3 | 129 | 55 |
| Massachusetts | 166 | 15 | 106 | 45 |
| Montana | 166 | 13 | 140 | 13 |
| Arizona | 164 | 2 | 160 | 2 |
| West Virginia | 160 | 2 | 98 | 60 |
| Alaska | 159 | 1 | 146 | 12 |
| Maine | 140 | 13 | 126 | 1 |
| North Carolina | 130 | 9 | 105 | 16 |
| New Mexico | 127 | 4 | 114 | 9 |
| North Dakota | 102 | 14 | 87 | 1 |
| Utah | 100 | 6 | 82 | 12 |
| Georgia | 99 | 1 | 81 | 17 |
| Illinois | 99 | 3 | 85 | 11 |
| Nevada | 94 | 0 | 85 | 9 |
| Rhode Island | 94 | 0 | 93 | 1 |
| New Hampshire | 86 | 2 | 78 | 6 |
| Hawaii | 83 | 0 | 82 | 1 |
| Kentucky | 56 | 16 | 39 | 1 |
| Maryland | 54 | 1 | 51 | 2 |
| Wyoming | 51 | 1 | 48 | 2 |
| Delaware | 39 | 0 | 39 | 0 |
| Ohio | 12 | 2 | 4 | 6 |
| Virginia | 8 | 0 | 8 | 0 |
| District of Columbia | 5 | 0 | 4 | 1 |
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.