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 |
|---|---|---|---|---|---|
| SHEEP HAMMOCK CREEK | Florida | Scour Critical — Countermeasures Installed | Fair | 1927 | 10,600 |
| BUTTERMILK SLOUGH N FORK | Florida | Scour Critical — Countermeasures Installed | Fair | 1927 | 10,600 |
| GRANDE DE MANATI RIVER | Puerto Rico | Scour Critical — Countermeasures Installed | Fair | 1968 | 10,600 |
| GRANDE DE MANATI RIVER | Puerto Rico | Scour Critical — Countermeasures Installed | Fair | 1968 | 10,600 |
| JANER CREEK | Puerto Rico | Scour Critical — Countermeasures Installed | Fair | 1924 | 10,600 |
| WATER ABERJONA RIVER | Massachusetts | Scour Critical — Countermeasures Installed | Fair | 1890 | 10,600 |
| PASSAIC RIVER | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1898 | 10,590 |
| MUCKLEROY CREEK | Alabama | Scour Critical — Countermeasures Installed | Fair | 1961 | 10,585 |
| MUCKLEROY CREEK | Alabama | Scour Critical — Countermeasures Installed | Fair | 1961 | 10,585 |
| COMB ST112 & DEERFLD R | Massachusetts | Scour Critical — Countermeasures Installed | Fair | 1954 | 10,562 |
| ALABAMA RIVER | Alabama | Scour Critical — Countermeasures Installed | Fair | 1970 | 10,540 |
| ALA. RIVER RELIEF #3 | Alabama | Scour Critical — Countermeasures Installed | Fair | 1970 | 10,540 |
| DARDENNE CR | Missouri | Scour Critical — Countermeasures Installed | Fair | 1974 | 10,518 |
| McClellan Wash | Arizona | Scour Critical — Countermeasures Installed | Fair | 1960 | 10,511 |
| Santa Cruz Wash | Arizona | Scour Critical — Countermeasures Installed | Fair | 1960 | 10,511 |
| MAR DES CYG RIV PD PASS | Kansas | Scour Critical — Countermeasures Installed | Fair | 1958 | 10,506 |
| MAR DES CYG RIV PD PASS | Kansas | Scour Critical — Countermeasures Installed | Fair | 1958 | 10,506 |
| INTRACOASTAL WATERWAY | Florida | Scour Critical — Countermeasures Installed | Fair | 1985 | 10,502 |
| SILVERSMITH CREEK | Florida | Scour Critical — Countermeasures Installed | Good | 1980 | 10,501 |
| HEMBREE CREEK | South Carolina | Scour Critical — Countermeasures Installed | Good | 1988 | 10,500 |
| WATER COYS BROOK | Massachusetts | Scour Critical — Countermeasures Installed | Fair | 1901 | 10,500 |
| WILLS BRANCH | Florida | Scour Critical — Countermeasures Installed | Good | 1969 | 10,500 |
| PETTAQUAMSCUTT RIVER | Rhode Island | Scour Critical — Countermeasures Installed | Fair | 1934 | 10,491 |
| ALBERTSONS BROOK | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1930 | 10,490 |
| GREAT SWAMP BRANCH | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1930 | 10,475 |
| WOLF RIVER | Tennessee | Scour Critical — Countermeasures Installed | Poor | 1980 | 10,454 |
| ALABAMA RIVER | Alabama | Scour Critical — Countermeasures Installed | Fair | 1955 | 10,450 |
| Santa Cruz River | Arizona | Scour Critical — Countermeasures Installed | Fair | 1960 | 10,449 |
| CAYUGA CREEK | New York | Scour Critical — Countermeasures Installed | Fair | 1931 | 10,449 |
| ST JOHNS DTCH | Missouri | Scour Critical — Countermeasures Installed | Fair | 1964 | 10,439 |
| LAMINGTON RIVER | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1988 | 10,424 |
| NIX CREEK | Arkansas | Scour Critical — Countermeasures Installed | Fair | 1950 | 10,414 |
| DOS BOCAS CREEK | Puerto Rico | Scour Critical — Countermeasures Installed | Fair | 1980 | 10,400 |
| HARDY MILL CREEK | Georgia | Scour Critical — Countermeasures Installed | Good | 1988 | 10,400 |
| MAD RIVER | Connecticut | Scour Critical — Countermeasures Installed | Fair | 1935 | 10,400 |
| KAIEIE STRM | Hawaii | Scour Critical — Countermeasures Installed | Fair | 1967 | 10,400 |
| CROOKED OAK CREEK | Oklahoma | Scour Critical — Countermeasures Installed | Poor | 1942 | 10,400 |
| Willamette River | Oregon | Scour Critical — Countermeasures Installed | Fair | 1925 | 10,393 |
| WAIBLE CREEK | Oregon | Scour Critical — Countermeasures Installed | Fair | 1972 | 10,382 |
| NASH CREEK | Michigan | Scour Critical — Countermeasures Installed | Fair | 1962 | 10,377 |
| N. FK. FORKED DEER RIVER | Tennessee | Scour Critical — Countermeasures Installed | Fair | 1959 | 10,376 |
| N. FK. FORKED DEER RIVER | Tennessee | Scour Critical — Countermeasures Installed | Fair | 1959 | 10,376 |
| JAMES RIVER | North Dakota | Scour Critical — Countermeasures Installed | Fair | 1960 | 10,370 |
| S BR SHIAWASSEE RIVER | Michigan | Scour Critical — Countermeasures Installed | Fair | 1918 | 10,370 |
| WOODY BRANCH | Texas | Scour Critical — Countermeasures Installed | Good | 1985 | 10,361 |
| FIVE MILE CREEK | Texas | Scour Critical — Countermeasures Installed | Fair | 1970 | 10,356 |
| WHITE OAK CREEK | Texas | Scour Critical — Countermeasures Installed | Fair | 1947 | 10,351 |
| North Yamhill River | Oregon | Scour Critical — Countermeasures Installed | Fair | 1921 | 10,350 |
| CLIFTY CREEK | Indiana | Scour Critical — Countermeasures Installed | Good | 1962 | 10,341 |
| PADANARAM BROOK | Connecticut | Scour Critical — Countermeasures Installed | Fair | 1899 | 10,334 |
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.