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 |
|---|---|---|---|---|---|
| Brazos River | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1967 | 2,903 |
| Boeuf River | Arkansas | Scour Critical — Countermeasures Ineffective | Poor | 1950 | 2,900 |
| KELSEY CREEK | California | Scour Critical — Countermeasures Ineffective | Good | 2023 | 2,900 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2007 | 2,892 |
| HCFCD DITCH | Texas | Scour Critical — Countermeasures Ineffective | Good | 1970 | 2,841 |
| DUCK CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1930 | 2,839 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 1922 | 2,834 |
| ELM BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1978 | 2,827 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 1945 | 2,815 |
| HOG WALLOW CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1945 | 2,815 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 1945 | 2,815 |
| Fountain Creek | Arkansas | Scour Critical — Countermeasures Ineffective | Good | 1975 | 2,800 |
| SABINE CREEK BRANCH NO 1 | Texas | Scour Critical — Countermeasures Ineffective | Good | 2024 | 2,779 |
| DICKINSON BYU | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1990 | 2,778 |
| BIG SANDY CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1948 | 2,750 |
| TOWN RESACA CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1999 | 2,744 |
| TOWN RESACA CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1999 | 2,744 |
| TRIB. KEE BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1973 | 2,743 |
| DUCK CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1939 | 2,723 |
| FAUGHT CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1949 | 2,718 |
| BLACKWATER CRK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1955 | 2,710 |
| N FLOODWAY PILOT CHANNEL | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1986 | 2,704 |
| MERCEDES CANAL | Texas | Scour Critical — Countermeasures Ineffective | Good | 2007 | 2,704 |
| Corpus Christi Ship Chan | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2002 | 2,703 |
| INDIAN CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1957 | 2,692 |
| WHITE OAK BAYOU | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1987 | 2,690 |
| WHITE OAK BAYOU | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1987 | 2,690 |
| DRAINAGE DITCH | Texas | Scour Critical — Countermeasures Ineffective | Good | 1988 | 2,687 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 1962 | 2,685 |
| HIGHLAND BAYOU | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2006 | 2,680 |
| POWDER CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1938 | 2,680 |
| SLOANS CREEK | Texas | Scour Critical — Countermeasures Ineffective | Poor | 1931 | 2,676 |
| E. CADDO CR | Texas | Scour Critical — Countermeasures Ineffective | Good | 1970 | 2,675 |
| E. CADDO CR. REL. | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1970 | 2,675 |
| FARBER BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Good | 1970 | 2,675 |
| WILLOW GROVE CREEK | New York | Scour Critical — Countermeasures Ineffective | Good | 2024 | 2,665 |
| TOWN BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1935 | 2,657 |
| WHITE OAK CREEK REL #3 | Texas | Scour Critical — Countermeasures Ineffective | Good | 1981 | 2,651 |
| DRY CIBOLO CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1925 | 2,647 |
| CIBOLO CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1925 | 2,647 |
| WOLF CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1969 | 2,640 |
| BEASLEY BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1974 | 2,640 |
| ELKHART BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Good | 1969 | 2,630 |
| San Pedro Creek | Texas | Scour Critical — Countermeasures Ineffective | Good | 2023 | 2,630 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1962 | 2,629 |
| LONG BRANCH SALT CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1934 | 2,623 |
| ELM CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2022 | 2,623 |
| FLAT CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2010 | 2,623 |
| GRASSHOPPER CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1952 | 2,623 |
| WEST FORK OF POND CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1968 | 2,621 |
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.