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 |
|---|---|---|---|---|---|
| SPRING CREEK | Texas | Scour Critical — Countermeasures Installed | Good | 1984 | 16,126 |
| GRAND RIVER | Michigan | Scour Critical — Countermeasures Installed | Poor | 1955 | 16,125 |
| PASCACK BROOK | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1980 | 16,113 |
| TRIB OF ROYCE BROOK | New Jersey | Scour Critical — Countermeasures Installed | Good | 1979 | 16,104 |
| RED CLAY CREEK | Delaware | Scour Critical — Countermeasures Installed | Fair | 1967 | 16,101 |
| NICHOLAS CREEK | South Carolina | Scour Critical — Countermeasures Installed | Good | 1994 | 16,100 |
| CREEK FRONTAGE RT | Oregon | Scour Critical — Countermeasures Installed | Good | 1959 | 16,064 |
| CREEK FRONTAGE RT | Oregon | Scour Critical — Countermeasures Installed | Good | 1959 | 16,064 |
| EAST FORK MCKAMY BRANCH | Texas | Scour Critical — Countermeasures Installed | Fair | 1989 | 16,047 |
| W BR BRANDYWINE CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Poor | 1914 | 16,027 |
| B-80A OVER JOHNSON CREEK | Oregon | Scour Critical — Countermeasures Installed | Fair | 1971 | 16,018 |
| Intracoastal Waterway | Florida | Scour Critical — Countermeasures Installed | Fair | 1952 | 16,000 |
| BOOKER CREEK | Florida | Scour Critical — Countermeasures Installed | Fair | 1921 | 16,000 |
| FOUR MILE CANYON CREEK | Colorado | Scour Critical — Countermeasures Installed | Fair | 1957 | 16,000 |
| STILL RIVER | Connecticut | Scour Critical — Countermeasures Installed | Fair | 1925 | 16,000 |
| LAS VEGAS WASH | Nevada | Scour Critical — Countermeasures Installed | Good | 1979 | 16,000 |
| S BR PAW PAW RIVER | Michigan | Scour Critical — Countermeasures Installed | Fair | 1960 | 15,986 |
| S BR PAW PAW RIVER | Michigan | Scour Critical — Countermeasures Installed | Fair | 1960 | 15,986 |
| BRANCH RVR & JOSLIN RD | Rhode Island | Scour Critical — Countermeasures Installed | Poor | 1967 | 15,976 |
| DRY CREEK | Washington | Scour Critical — Countermeasures Installed | Poor | 1967 | 15,974 |
| N BRANCH COOPER RIVER | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1935 | 15,947 |
| WILLIAMS CREEK | Indiana | Scour Critical — Countermeasures Installed | Fair | 1930 | 15,943 |
| GRAND RIVER | Michigan | Scour Critical — Countermeasures Installed | Poor | 1915 | 15,940 |
| FURNACE HILL BROOK | Rhode Island | Scour Critical — Countermeasures Installed | Fair | 1957 | 15,930 |
| WALNUT FORK | Indiana | Scour Critical — Countermeasures Installed | Fair | 1964 | 15,924 |
| WISSAHICKON CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Poor | 1888 | 15,917 |
| LYNCHES LAKE | South Carolina | Scour Critical — Countermeasures Installed | Fair | 1928 | 15,900 |
| LITTLE BUTTE CREEK | Oregon | Scour Critical — Countermeasures Installed | Fair | 1981 | 15,897 |
| Jackson Creek | Oregon | Scour Critical — Countermeasures Installed | Good | 1919 | 15,894 |
| FLINT RIVER | Michigan | Scour Critical — Countermeasures Installed | Fair | 1926 | 15,881 |
| GREENVILLE BROOK | Rhode Island | Scour Critical — Countermeasures Installed | Fair | 1929 | 15,861 |
| GRANDE DE MANATI RIVER | Puerto Rico | Scour Critical — Countermeasures Installed | Fair | 1975 | 15,800 |
| SHUNGANUNGA CREEK | Kansas | Scour Critical — Countermeasures Installed | Fair | 1960 | 15,800 |
| SHUNGANUNGA CREEK | Kansas | Scour Critical — Countermeasures Installed | Fair | 1960 | 15,800 |
| JOHNS CREEK | Washington | Scour Critical — Countermeasures Installed | Fair | 1948 | 15,751 |
| AQUIA CREEK | Virginia | Scour Critical — Countermeasures Installed | Fair | 1957 | 15,728 |
| MILL CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Poor | 1932 | 15,720 |
| MILL CANAL | Rhode Island | Scour Critical — Countermeasures Installed | Fair | 1918 | 15,715 |
| WEST BRANCH TROUT BROOK | Connecticut | Scour Critical — Countermeasures Installed | Fair | 1901 | 15,660 |
| SNOHOMISH R & TESTER RD | Washington | Scour Critical — Countermeasures Installed | Fair | 1963 | 15,631 |
| AQUETONG CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1939 | 15,615 |
| HEATH CREEK | Texas | Scour Critical — Countermeasures Installed | Fair | 1971 | 15,612 |
| WAILUKU STRM | Hawaii | Scour Critical — Countermeasures Installed | Fair | 1950 | 15,600 |
| HICKORY CREEK | Michigan | Scour Critical — Countermeasures Installed | Good | 1969 | 15,600 |
| Guanajibo River | Puerto Rico | Scour Critical — Countermeasures Installed | Fair | 1998 | 15,600 |
| DEEP CREEK | Oregon | Scour Critical — Countermeasures Installed | Fair | 1957 | 15,600 |
| FRANK & POET DRAIN | Michigan | Scour Critical — Countermeasures Installed | Fair | 1958 | 15,575 |
| FRANK & POET DRAIN | Michigan | Scour Critical — Countermeasures Installed | Fair | 1958 | 15,575 |
| LONES DITCH | Indiana | Scour Critical — Countermeasures Installed | Fair | 1953 | 15,569 |
| PRICE CREEK | Texas | Scour Critical — Countermeasures Installed | Fair | 1972 | 15,568 |
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.