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 |
|---|---|---|---|---|---|
| BEAVERHEAD RIVER | Montana | Scour Critical — Countermeasures Installed | Fair | 1949 | 2,865 |
| COCKEREL CREEK | Louisiana | Scour Critical — Countermeasures Installed | Fair | 1967 | 2,862 |
| CREEK | Louisiana | Scour Critical — Countermeasures Installed | Poor | 1967 | 2,862 |
| CREEK | Louisiana | Scour Critical — Countermeasures Installed | Fair | 1970 | 2,862 |
| PIGEON RIVER | Tennessee | Scour Critical — Countermeasures Installed | Good | 1967 | 2,861 |
| DEAD CREEK | Michigan | Scour Critical — Countermeasures Installed | Fair | 1981 | 2,860 |
| DUNCAN CREEK | Wisconsin | Scour Critical — Countermeasures Installed | Poor | 1934 | 2,855 |
| POWDER R (HUGHES LN) | Oregon | Scour Critical — Countermeasures Installed | Good | 1966 | 2,854 |
| NATALBANY RIVER | Louisiana | Scour Critical — Countermeasures Installed | Fair | 1957 | 2,854 |
| WILSON STREAM | Maine | Scour Critical — Countermeasures Installed | Poor | 1958 | 2,854 |
| WEBER RIVER | Utah | Scour Critical — Countermeasures Installed | Fair | 1936 | 2,848 |
| DUCK RIVER | Tennessee | Scour Critical — Countermeasures Installed | Fair | 1951 | 2,848 |
| FIVE MILE CREEK | Texas | Scour Critical — Countermeasures Installed | Fair | 1961 | 2,843 |
| COLE CREEK | Texas | Scour Critical — Countermeasures Installed | Fair | 1975 | 2,842 |
| SMACKOVER RELIEF | Arkansas | Scour Critical — Countermeasures Installed | Fair | 1974 | 2,840 |
| LEAF RIVER RELIEF | Mississippi | Scour Critical — Countermeasures Installed | Fair | 1967 | 2,840 |
| NASELLE R | Washington | Scour Critical — Countermeasures Installed | Good | 1953 | 2,839 |
| LITT BEAVER KILL | New York | Scour Critical — Countermeasures Installed | Fair | 1935 | 2,839 |
| CUB CREEK | Tennessee | Scour Critical — Countermeasures Installed | Fair | 1925 | 2,836 |
| ROBERTSON CREEK | Tennessee | Scour Critical — Countermeasures Installed | Fair | 1925 | 2,836 |
| CYPRESS CREEK | Tennessee | Scour Critical — Countermeasures Installed | Fair | 1925 | 2,836 |
| BEECH CR(MT VERNON) | Oregon | Scour Critical — Countermeasures Installed | Fair | 1956 | 2,836 |
| EVANS BRANCH ROUGE RIVER | Michigan | Scour Critical — Countermeasures Installed | Fair | 1970 | 2,834 |
| HAMMONASSET RIVER | Connecticut | Scour Critical — Countermeasures Installed | Fair | 1935 | 2,833 |
| BEAVER DAM RUN | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1953 | 2,830 |
| TUPPER BROOK | Michigan | Scour Critical — Countermeasures Installed | Fair | 1980 | 2,830 |
| LIMESTONE CREEK | New York | Scour Critical — Countermeasures Installed | Fair | 1923 | 2,829 |
| CREEK | Louisiana | Scour Critical — Countermeasures Installed | Fair | 1958 | 2,828 |
| NORTH CHENIERE CR | Louisiana | Scour Critical — Countermeasures Installed | Poor | 1958 | 2,828 |
| CREEK | Louisiana | Scour Critical — Countermeasures Installed | Fair | 1958 | 2,828 |
| MAD RIVER | New Hampshire | Scour Critical — Countermeasures Installed | Poor | 1979 | 2,828 |
| KIOWA BRANCH | Texas | Scour Critical — Countermeasures Installed | Fair | 1951 | 2,827 |
| BRANCH | Tennessee | Scour Critical — Countermeasures Installed | Fair | 1962 | 2,822 |
| BEAVER CREEK | Tennessee | Scour Critical — Countermeasures Installed | Fair | 1962 | 2,822 |
| GASCONADE RVR | Missouri | Scour Critical — Countermeasures Installed | Fair | 1964 | 2,822 |
| SANDY CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1950 | 2,818 |
| LABORDE BRANCH SANDY CR | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1950 | 2,818 |
| BITTERROOT RIVER | Montana | Scour Critical — Countermeasures Installed | Fair | 1974 | 2,814 |
| INDIAN CABIN CREEK | New Jersey | Scour Critical — Countermeasures Installed | Poor | 1919 | 2,813 |
| DUKES BROOK | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1925 | 2,810 |
| SOUTH YAMHILL RIVER | Oregon | Scour Critical — Countermeasures Installed | Fair | 1970 | 2,809 |
| E FORK TRINITY RIVER | Texas | Scour Critical — Countermeasures Installed | Fair | 1982 | 2,805 |
| SIX MILE CREEK | Indiana | Scour Critical — Countermeasures Installed | Fair | 1934 | 2,803 |
| BRANCH BRANDYWINE CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Poor | 1935 | 2,802 |
| TRIB LITTLE SWATARA CK | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1934 | 2,801 |
| CATHERINE CR (DAVIS DAM) | Oregon | Scour Critical — Countermeasures Installed | Fair | 1966 | 2,801 |
| SNAKE RIVER | Idaho | Scour Critical — Countermeasures Installed | Fair | 1967 | 2,800 |
| MIDDLE BRANCH BUSHY CK | South Carolina | Scour Critical — Countermeasures Installed | Fair | 1982 | 2,800 |
| SALKEHATCHIE RIVER SWAMP | South Carolina | Scour Critical — Countermeasures Installed | Fair | 2002 | 2,800 |
| GUAMANI RIVER | Puerto Rico | Scour Critical — Countermeasures Installed | Fair | 1925 | 2,800 |
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.