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 |
|---|---|---|---|---|---|
| JOES CREEK | Florida | Scour Critical — Countermeasures Installed | Good | 1981 | 6,000 |
| BLACK CREEK | South Carolina | Scour Critical — Countermeasures Installed | Fair | 1967 | 6,000 |
| WARES CREEK | Florida | Scour Critical — Countermeasures Installed | Fair | 1963 | 6,000 |
| BRUSHY CREEK | South Carolina | Scour Critical — Countermeasures Installed | Good | 1977 | 6,000 |
| SACRAMENTO RIVER | California | Scour Critical — Countermeasures Installed | Poor | 1975 | 6,000 |
| SCHUYLKILL RIVER | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1932 | 5,993 |
| CROCKERY CREEK | Michigan | Scour Critical — Countermeasures Installed | Poor | 1958 | 5,976 |
| MT SCOTT CREEK | Oregon | Scour Critical — Countermeasures Installed | Good | 1970 | 5,974 |
| MUDDY CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Poor | 1930 | 5,968 |
| TENAKILL BROOK | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1955 | 5,968 |
| SKIPPACK CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Poor | 1932 | 5,958 |
| MUSTANG BAYOU | Texas | Scour Critical — Countermeasures Installed | Fair | 2013 | 5,948 |
| POND CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1940 | 5,948 |
| WALNUT RIV & LOCAL RD | Kansas | Scour Critical — Countermeasures Installed | Good | 1939 | 5,944 |
| OAK CR | Oregon | Scour Critical — Countermeasures Installed | Fair | 1978 | 5,930 |
| N BRANCH RIVER | New Hampshire | Scour Critical — Countermeasures Installed | Good | 1988 | 5,929 |
| METZLERS BROOK | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1962 | 5,929 |
| FURNACE HILL BROOK | Rhode Island | Scour Critical — Countermeasures Installed | Fair | 2000 | 5,919 |
| DRAIN DTCH NO 1 | Missouri | Scour Critical — Countermeasures Installed | Fair | 1985 | 5,914 |
| SYCAMORE CREEK | Michigan | Scour Critical — Countermeasures Installed | Poor | 1918 | 5,910 |
| GEORGES CREEK | South Carolina | Scour Critical — Countermeasures Installed | Fair | 1968 | 5,900 |
| RIO CULEBRINAS | Puerto Rico | Scour Critical — Countermeasures Installed | Poor | 1901 | 5,900 |
| CHANNEL | Puerto Rico | Scour Critical — Countermeasures Installed | Fair | 1966 | 5,900 |
| MILL RIVER | Connecticut | Scour Critical — Countermeasures Installed | Fair | 1936 | 5,900 |
| DUCK CREEK | Wisconsin | Scour Critical — Countermeasures Installed | Good | 1975 | 5,900 |
| SOUTHWICK CREEK | Wisconsin | Scour Critical — Countermeasures Installed | Fair | 1939 | 5,900 |
| SUWANNEE RIVER | Florida | Scour Critical — Countermeasures Installed | Fair | 1989 | 5,900 |
| SPRING CREEK | Wisconsin | Scour Critical — Countermeasures Installed | Poor | 1935 | 5,900 |
| LEICESTER RIVER | Vermont | Scour Critical — Countermeasures Installed | Fair | 1943 | 5,900 |
| CATFISH BRANCH | South Carolina | Scour Critical — Countermeasures Installed | Poor | 1941 | 5,900 |
| MUD RUN | Pennsylvania | Scour Critical — Countermeasures Installed | Poor | 1932 | 5,877 |
| THIRD RIVER | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1960 | 5,872 |
| PUGET SOUND @ EDMONDS | Washington | Scour Critical — Countermeasures Installed | Fair | 1995 | 5,870 |
| WISSAHICKON CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Poor | 1884 | 5,864 |
| HCFCD DITCH | Texas | Scour Critical — Countermeasures Installed | Fair | 1970 | 5,864 |
| GRAND RIVER | Michigan | Scour Critical — Countermeasures Installed | Poor | 1966 | 5,860 |
| PARSONS CREEK | Oregon | Scour Critical — Countermeasures Installed | Fair | 1978 | 5,859 |
| LIGHTNING CREEK | Kansas | Scour Critical — Countermeasures Installed | Good | 1987 | 5,858 |
| CROOKED CR | Missouri | Scour Critical — Countermeasures Installed | Fair | 1977 | 5,858 |
| ARKANSAS RIVER | Kansas | Scour Critical — Countermeasures Installed | Good | 1973 | 5,858 |
| ROCKAWAY RIVER | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1928 | 5,854 |
| CEDAR CREEK | Washington | Scour Critical — Countermeasures Installed | Fair | 1932 | 5,851 |
| WABASH RIVER | Indiana | Scour Critical — Countermeasures Installed | Fair | 1992 | 5,848 |
| MUSCONETCONG RIVER | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1932 | 5,846 |
| PINE RIVER | Michigan | Scour Critical — Countermeasures Installed | Poor | 1952 | 5,845 |
| TAMARACK CR | Michigan | Scour Critical — Countermeasures Installed | Fair | 1957 | 5,843 |
| DARBY CREEK / 3476-F8 | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1810 | 5,835 |
| DRAINAGE DITCH | Indiana | Scour Critical — Countermeasures Installed | Fair | 1923 | 5,828 |
| 142 MILE CREEK | Kansas | Scour Critical — Countermeasures Installed | Good | 1956 | 5,825 |
| 142 MILE CREEK | Kansas | Scour Critical — Countermeasures Installed | Fair | 1956 | 5,825 |
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.