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 |
|---|---|---|---|---|---|
| MUSKEE CREEK | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1987 | 19,874 |
| MANUMUSKIN RIVER | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1930 | 19,874 |
| ROGUE RIVER (HOMESTEAD) | Oregon | Scour Critical — Countermeasures Installed | Fair | 1961 | 19,847 |
| ROGUE RIVER (HOMESTEAD) | Oregon | Scour Critical — Countermeasures Installed | Fair | 1961 | 19,847 |
| PASSAIC RIVER | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1900 | 19,840 |
| SALINE RIVER | Michigan | Scour Critical — Countermeasures Installed | Fair | 1961 | 19,825 |
| SALINE RIVER | Michigan | Scour Critical — Countermeasures Installed | Fair | 1948 | 19,825 |
| WHITEWATER RIVER OVFL | Indiana | Scour Critical — Countermeasures Installed | Fair | 1965 | 19,818 |
| WHITEWATER RIVER OVFL | Indiana | Scour Critical — Countermeasures Installed | Fair | 1965 | 19,818 |
| CONNOR CREEK | Kansas | Scour Critical — Countermeasures Installed | Fair | 1985 | 19,800 |
| CONNOR CREEK | Kansas | Scour Critical — Countermeasures Installed | Good | 1985 | 19,800 |
| ASHLEY RIVER | South Carolina | Scour Critical — Countermeasures Installed | Poor | 1971 | 19,800 |
| WHITEWATER RIVER | Indiana | Scour Critical — Countermeasures Installed | Good | 1936 | 19,677 |
| SADDLE RIVER | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1945 | 19,664 |
| BOARDMAN RIVER | Michigan | Scour Critical — Countermeasures Installed | Poor | 1980 | 19,628 |
| HOOSIER CREEK | Tennessee | Scour Critical — Countermeasures Installed | Fair | 1968 | 19,597 |
| MINE RUN | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1951 | 19,593 |
| Creek | Oregon | Scour Critical — Countermeasures Installed | Good | 1992 | 19,591 |
| TURKEY CREEK | Kansas | Scour Critical — Countermeasures Installed | Good | 1986 | 19,581 |
| SANTA MONICA LAKE | Texas | Scour Critical — Countermeasures Installed | Fair | 1973 | 19,501 |
| SHELTON DITCH | Oregon | Scour Critical — Countermeasures Installed | Fair | 1975 | 19,501 |
| PAYETTE RIVER | Idaho | Scour Critical — Countermeasures Installed | Fair | 1968 | 19,500 |
| Cobbs Creek | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1948 | 19,500 |
| PEQUANNOCK RIVER | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1924 | 19,500 |
| GAS LINE WASH | California | Scour Critical — Countermeasures Installed | Fair | 1968 | 19,500 |
| GAS LINE WASH | California | Scour Critical — Countermeasures Installed | Good | 1968 | 19,500 |
| LAVA WASH | California | Scour Critical — Countermeasures Installed | Good | 1968 | 19,500 |
| LAVA WASH | California | Scour Critical — Countermeasures Installed | Good | 1968 | 19,500 |
| AIRPORT WASH | California | Scour Critical — Countermeasures Installed | Good | 1968 | 19,500 |
| AIRPORT WASH | California | Scour Critical — Countermeasures Installed | Good | 1968 | 19,500 |
| BLOSSOM WASH | California | Scour Critical — Countermeasures Installed | Fair | 1968 | 19,500 |
| BLOSSOM WASH | California | Scour Critical — Countermeasures Installed | Fair | 1968 | 19,500 |
| BLOOM WASH | California | Scour Critical — Countermeasures Installed | Fair | 1968 | 19,500 |
| BLOOM WASH | California | Scour Critical — Countermeasures Installed | Fair | 1968 | 19,500 |
| ANTHONY CREEK | Indiana | Scour Critical — Countermeasures Installed | Fair | 1964 | 19,477 |
| ANTHONY CREEK | Indiana | Scour Critical — Countermeasures Installed | Fair | 1964 | 19,477 |
| TOWAMENCIN CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Poor | 1986 | 19,455 |
| PERNICK CREEK | Michigan | Scour Critical — Countermeasures Installed | Good | 1992 | 19,439 |
| GEYER DITCH | Indiana | Scour Critical — Countermeasures Installed | Fair | 1925 | 19,425 |
| Oak Creek | Oregon | Scour Critical — Countermeasures Installed | Good | 1988 | 19,406 |
| QUINNIPIAC RIVER | Connecticut | Scour Critical — Countermeasures Installed | Fair | 1965 | 19,400 |
| ABERS CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1952 | 19,380 |
| PINE RUN | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1941 | 19,355 |
| FLINT RIVER | Michigan | Scour Critical — Countermeasures Installed | Good | 1994 | 19,352 |
| BRUSH BAYOU | Louisiana | Scour Critical — Countermeasures Installed | Fair | 1977 | 19,314 |
| St. Cloud Canal C-31 | Florida | Scour Critical — Countermeasures Installed | Fair | 1957 | 19,300 |
| SAGINAW RIVER AND MCRR | Michigan | Scour Critical — Countermeasures Installed | Fair | 1987 | 19,300 |
| BEAVER RUN(PAULINS KILL) | New Jersey | Scour Critical — Countermeasures Installed | Poor | 1915 | 19,298 |
| PAULINS KILL | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1990 | 19,297 |
| TOWAMENCIN CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1962 | 19,293 |
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.