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 |
|---|---|---|---|---|---|
| CUTHAND CRK REL. | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1949 | 1,510 |
| Seabourne Creek | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1929 | 1,504 |
| Drainage Ditch | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1929 | 1,504 |
| DEEP BRANCH CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1954 | 1,504 |
| Cedar Creek Relief | Texas | Scour Critical — Countermeasures Ineffective | Good | 2022 | 1,500 |
| LIVE BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Good | 2004 | 1,500 |
| Unnamed creek | Florida | Scour Critical — Countermeasures Ineffective | Good | 2006 | 1,500 |
| Williams Creek | Florida | Scour Critical — Countermeasures Ineffective | Good | 2013 | 1,500 |
| Cedar Creek | Texas | Scour Critical — Countermeasures Ineffective | Good | 2022 | 1,500 |
| Unnamed Creek | Florida | Scour Critical — Countermeasures Ineffective | Good | 2003 | 1,500 |
| Drainage Ditch | Florida | Scour Critical — Countermeasures Ineffective | Good | 2004 | 1,500 |
| QUARTERMASTER REACH | California | Scour Critical — Countermeasures Ineffective | Good | 2021 | 1,500 |
| Williams Creek | Florida | Scour Critical — Countermeasures Ineffective | Good | 2006 | 1,500 |
| LITTLE WHITE OAK BAYOU | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1995 | 1,500 |
| LITTLE WHITE OAK BAYOU | Texas | Scour Critical — Countermeasures Ineffective | Good | 1999 | 1,500 |
| Drainage Ditch | Florida | Scour Critical — Countermeasures Ineffective | Good | 2005 | 1,500 |
| LAKE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2009 | 1,493 |
| POND CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1940 | 1,490 |
| MORRISON CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1992 | 1,490 |
| WILLOW FLATS | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2015 | 1,487 |
| CANEY CREEK RELIEF | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1980 | 1,480 |
| DUCK CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1973 | 1,477 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1944 | 1,476 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1988 | 1,476 |
| Unnamed arroyo | New Mexico | Scour Critical — Countermeasures Ineffective | Good | 2024 | 1,464 |
| Unnamed arroyo | New Mexico | Scour Critical — Countermeasures Ineffective | Good | 2024 | 1,464 |
| Unnamed arroyo | New Mexico | Scour Critical — Countermeasures Ineffective | Good | 2024 | 1,464 |
| Unnamed arroyo | New Mexico | Scour Critical — Countermeasures Ineffective | Good | 2024 | 1,464 |
| DRAINAGE DITCH | Texas | Scour Critical — Countermeasures Ineffective | Good | 1989 | 1,461 |
| WEST CADDO CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1986 | 1,460 |
| BRUSHY CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1986 | 1,460 |
| PARADISE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1936 | 1,456 |
| CCWID#11 IRRIG. CANAL | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2006 | 1,450 |
| Fivemile Creek | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1965 | 1,450 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1970 | 1,446 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1970 | 1,445 |
| DUCK CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1962 | 1,445 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1970 | 1,445 |
| RAYMONDVILLE DRAIN | Texas | Scour Critical — Countermeasures Ineffective | Good | 1969 | 1,445 |
| HC & WC MASTER DRAIN | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1986 | 1,443 |
| CROOKS CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1954 | 1,433 |
| BITTER CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1929 | 1,432 |
| BITTER CREEK BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1929 | 1,432 |
| Turkey Creek | Texas | Scour Critical — Countermeasures Ineffective | Good | 1981 | 1,427 |
| CHIPPEWA RIVER | Minnesota | Scour Critical — Countermeasures Ineffective | Fair | 2023 | 1,427 |
| Snake Creek | Texas | Scour Critical — Countermeasures Ineffective | Good | 1981 | 1,427 |
| PACE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1958 | 1,422 |
| BOIS DARC CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1958 | 1,422 |
| Draw | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1950 | 1,409 |
| Draw | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1950 | 1,409 |
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.