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 |
|---|---|---|---|---|---|
| DRY FK LITTLE WICHITA RV | Texas | Scour Critical — Countermeasures Ineffective | Good | 2004 | 19 |
| DENTON CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1995 | 19 |
| DYE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1999 | 19 |
| SALT CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1985 | 19 |
| LITTLE SALT CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2010 | 18 |
| GROVE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2003 | 18 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1990 | 18 |
| WAGON BR | Texas | Scour Critical — Countermeasures Ineffective | Good | 2005 | 17 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 2002 | 16 |
| BARREL SPRINGS CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1992 | 16 |
| BRADEN BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1998 | 16 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2000 | 16 |
| GILBERT CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1940 | 16 |
| PECAN CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1994 | 15 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 2006 | 15 |
| POWDER MILL GULCH | Washington | Scour Critical — Countermeasures Ineffective | Fair | 1993 | 15 |
| WANDERERS CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2008 | 15 |
| HOG CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1992 | 15 |
| BELL BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Good | 2010 | 14 |
| MUHLE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2015 | 14 |
| RED OAK CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2000 | 14 |
| PARADISE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2009 | 14 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 2001 | 13 |
| ELIZABETH CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2006 | 12 |
| LAKE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2016 | 12 |
| COOL CREEK | Texas | Scour Critical — Countermeasures Ineffective | Poor | 1949 | 12 |
| ASA CREEK | Illinois | Scour Critical — Countermeasures Ineffective | Fair | 1960 | 12 |
| GRIMES CREEK | Idaho | Scour Critical — Countermeasures Ineffective | Good | 1982 | 12 |
| N BR TWO RIVERS | Minnesota | Scour Critical — Countermeasures Ineffective | Poor | 1907 | 12 |
| Red Creek | Alabama | Scour Critical — Countermeasures Ineffective | Good | 2021 | 12 |
| Calebee Creek | Alabama | Scour Critical — Countermeasures Ineffective | Good | 2021 | 12 |
| Calebee Creek | Alabama | Scour Critical — Countermeasures Ineffective | Good | 2021 | 12 |
| JONES CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2006 | 12 |
| JONES CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2006 | 12 |
| BEAVER CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1991 | 12 |
| ELM CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1946 | 12 |
| RED CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1952 | 11 |
| COCKERELL CR | Texas | Scour Critical — Countermeasures Ineffective | Good | 2010 | 11 |
| VALLEY BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Good | 2017 | 11 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 2004 | 11 |
| ROCK CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2004 | 11 |
| NORTH FISH CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1987 | 11 |
| BELKNAP CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1995 | 11 |
| W FK OF TRINTY RIVER | Texas | Scour Critical — Countermeasures Ineffective | Good | 2005 | 10 |
| FISH CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1989 | 10 |
| Drain (H&P Dr. South) | Texas | Scour Critical — Countermeasures Ineffective | Good | 2024 | 10 |
| RICHLAND CREEK TRIBUTARY | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2008 | 10 |
| SANDY CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2001 | 10 |
| CAMERON CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2010 | 10 |
| Drain (H&P Dr. North) | Texas | Scour Critical — Countermeasures Ineffective | Good | 2024 | 10 |
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.