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 |
|---|---|---|---|---|---|
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 2012 | 24 |
| MOUNTAIN CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1995 | 24 |
| RED BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2007 | 24 |
| MESQUITE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2008 | 23 |
| FARNASH CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2002 | 23 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 2010 | 23 |
| DUFFAU CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1935 | 23 |
| SALT CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1988 | 23 |
| S FK LITTLE WICHITA RI | Texas | Scour Critical — Countermeasures Ineffective | Good | 2008 | 23 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 2008 | 23 |
| BRANCH WILLAWALLA CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1991 | 23 |
| BRANCH N BINGHAM CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1997 | 23 |
| BRANCH CLEAR CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2005 | 23 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 2008 | 23 |
| DRY FK LTL WICHITA RIVER | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2013 | 22 |
| SALT CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2005 | 22 |
| PARADISE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1940 | 22 |
| MOSSY CREEK | Texas | Scour Critical — Countermeasures Ineffective | Poor | 1988 | 22 |
| MESQUITE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2001 | 22 |
| PECAN CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2007 | 22 |
| Dark Hollow Branch | Texas | Scour Critical — Countermeasures Ineffective | Poor | 1990 | 21 |
| BAKER BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1996 | 21 |
| BIG ONION CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2000 | 21 |
| S.FORK LONG CREEK | Oregon | Scour Critical — Countermeasures Ineffective | Good | 2024 | 21 |
| BEAVER CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2008 | 21 |
| BRADEN BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Good | 2001 | 21 |
| HCFCD Ditch | Texas | Scour Critical — Countermeasures Ineffective | Good | 2012 | 20 |
| DUCK CREEK * STEVEN | Ohio | Scour Critical — Countermeasures Ineffective | Good | 2024 | 20 |
| BAKER BRANCH TRIBUTARY | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2010 | 20 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 2006 | 20 |
| BUFFALO CREEK | West Virginia | Scour Critical — Countermeasures Ineffective | Fair | 1991 | 20 |
| CEDAR CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1983 | 20 |
| PECAN CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1976 | 20 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 2012 | 20 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 2002 | 20 |
| INDIAN CREEK | Texas | Scour Critical — Countermeasures Ineffective | Poor | 1983 | 20 |
| PANTHER CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2001 | 20 |
| WIGGINS CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2024 | 20 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1936 | 20 |
| RABBIT RIVER | Minnesota | Scour Critical — Countermeasures Ineffective | Poor | 1920 | 20 |
| Cambridge Canal | Nebraska | Scour Critical — Countermeasures Ineffective | Fair | 1970 | 20 |
| N FK ZUMBRO RIVER | Minnesota | Scour Critical — Countermeasures Ineffective | Poor | 1920 | 20 |
| NOKASIPPI RIVER | Minnesota | Scour Critical — Countermeasures Ineffective | Poor | 1908 | 20 |
| HCFCD DITCH | Texas | Scour Critical — Countermeasures Ineffective | Good | 2005 | 20 |
| CANNON RIVER | Minnesota | Scour Critical — Countermeasures Ineffective | Poor | 1921 | 20 |
| LAWRENCE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2010 | 20 |
| EAST JONES CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2000 | 20 |
| SOUTH COW BAYOU | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2015 | 20 |
| ALVEY WASH | Utah | Scour Critical — Countermeasures Ineffective | Poor | 1987 | 19 |
| DENTON CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1995 | 19 |
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.