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 |
|---|---|---|---|---|---|
| Trib of Big Mineral Ck | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2012 | 88 |
| DRAINAGE DITCH | Texas | Scour Critical — Countermeasures Ineffective | Good | 2010 | 88 |
| BR OF ROCK CK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1961 | 85 |
| WHEELER CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2007 | 84 |
| MOUND CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2010 | 84 |
| WHEAT CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1995 | 83 |
| BOND CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2023 | 82 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1995 | 82 |
| LIVE OAK CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1975 | 82 |
| BITTER CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1969 | 81 |
| FLOYD BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1957 | 80 |
| DUCK CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1993 | 80 |
| E BR MONGAUP RVR | New York | Scour Critical — Countermeasures Ineffective | Good | 2024 | 80 |
| QUINTA CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1989 | 80 |
| PETRONILA CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2006 | 80 |
| FOURMILE CREEK | West Virginia | Scour Critical — Countermeasures Ineffective | Poor | 1978 | 80 |
| HCFCD DITCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1986 | 80 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1996 | 80 |
| BRUSHY CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1983 | 80 |
| LEON CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2005 | 80 |
| MADERA DRAINAGE CANAL | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2008 | 80 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1996 | 80 |
| DRAINAGE DITCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2013 | 79 |
| YELLOW CREEK | Alabama | Scour Critical — Countermeasures Ineffective | Poor | 1950 | 79 |
| MALLARD CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1974 | 78 |
| ELAINES CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1963 | 78 |
| Dry Creek | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1995 | 76 |
| TOWNSEND CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2004 | 76 |
| Footbridge Trail | Washington | Scour Critical — Countermeasures Ineffective | Good | 2023 | 75 |
| BLACKBERRY CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1966 | 75 |
| South Fork Zumbro River | Minnesota | Scour Critical — Countermeasures Ineffective | Poor | 1895 | 75 |
| Creek | Alabama | Scour Critical — Countermeasures Ineffective | Good | 2023 | 75 |
| WILD HORSE SLOUGH | Texas | Scour Critical — Countermeasures Ineffective | Good | 2009 | 75 |
| STREAM | Illinois | Scour Critical — Countermeasures Ineffective | Fair | 1953 | 75 |
| SALT CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1998 | 72 |
| TRIB OF BRUSHY CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2006 | 72 |
| SOAP CREEK TRIBUTARY | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2002 | 72 |
| BRANCH MID BELKNAP CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2008 | 72 |
| CREEK | Arkansas | Scour Critical — Countermeasures Ineffective | Good | 1998 | 72 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1935 | 71 |
| COWHOUSE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1997 | 71 |
| BEAR CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1935 | 71 |
| NEDDY CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2009 | 70 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1983 | 70 |
| BUFFALO BAYOU | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2011 | 70 |
| CLEAR CREEK DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2004 | 70 |
| MUD FORK | West Virginia | Scour Critical — Countermeasures Ineffective | Poor | 1982 | 70 |
| SALT CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2016 | 70 |
| MAIN DITCH | Arkansas | Scour Critical — Countermeasures Ineffective | Fair | 2001 | 70 |
| MIDDLE CREEK | West Virginia | Scour Critical — Countermeasures Ineffective | Poor | 1979 | 70 |
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.