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 |
|---|---|---|---|---|---|
| RED CEDAR RIVER | Michigan | Scour Critical — Countermeasures Installed | Fair | 1963 | 17,675 |
| SELSERS CREEK | Louisiana | Scour Critical — Countermeasures Installed | Fair | 1975 | 17,665 |
| GRAND RIVER | Michigan | Scour Critical — Countermeasures Installed | Fair | 1948 | 17,638 |
| NEW RIVER AND 5TH AVE | Florida | Scour Critical — Countermeasures Installed | Fair | 1964 | 17,600 |
| CLEAR CREEK | Oregon | Scour Critical — Countermeasures Installed | Fair | 1957 | 17,600 |
| WEST RIVER | Connecticut | Scour Critical — Countermeasures Installed | Poor | 1950 | 17,600 |
| San Antonio River | Texas | Scour Critical — Countermeasures Installed | Fair | 1965 | 17,600 |
| WRECK POND | New Jersey | Scour Critical — Countermeasures Installed | Good | 1971 | 17,557 |
| N BR OF RARITAN RIVER | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1942 | 17,546 |
| GREYS CREEK | Louisiana | Scour Critical — Countermeasures Installed | Good | 1956 | 17,500 |
| Ventana Wash | Arizona | Scour Critical — Countermeasures Installed | Fair | 1967 | 17,470 |
| South Yamhill River | Oregon | Scour Critical — Countermeasures Installed | Good | 1992 | 17,452 |
| MAJADAS RIVER & PR 7 | Puerto Rico | Scour Critical — Countermeasures Installed | Poor | 1972 | 17,450 |
| S BR RANCOCAS CREEK | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1930 | 17,443 |
| KAWKAWLIN RIVER | Michigan | Scour Critical — Countermeasures Installed | Fair | 1931 | 17,442 |
| PINEY CREEK | Texas | Scour Critical — Countermeasures Installed | Fair | 1963 | 17,409 |
| SPROUT BROOK | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1940 | 17,401 |
| LITTLE SUGAR CREEK | Indiana | Scour Critical — Countermeasures Installed | Good | 1964 | 17,400 |
| WOLF CREEK | Kansas | Scour Critical — Countermeasures Installed | Fair | 1956 | 17,396 |
| STRANGER CREEK | Kansas | Scour Critical — Countermeasures Installed | Good | 1956 | 17,396 |
| STRANGER CREEK | Kansas | Scour Critical — Countermeasures Installed | Good | 1956 | 17,396 |
| WOLF CREEK | Kansas | Scour Critical — Countermeasures Installed | Good | 1956 | 17,396 |
| BRANCH NESHAMINY CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1973 | 17,386 |
| SUSQ RIVER RR SR 2037 | Pennsylvania | Scour Critical — Countermeasures Installed | Poor | 1924 | 17,383 |
| FIVE MILE CREEK | Texas | Scour Critical — Countermeasures Installed | Fair | 1953 | 17,321 |
| MERRIMACK RIVER | New Hampshire | Scour Critical — Countermeasures Installed | Fair | 1970 | 17,275 |
| N BR. RARITAN RIVER | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1942 | 17,240 |
| TURKEY CREEK | Tennessee | Scour Critical — Countermeasures Installed | Fair | 1934 | 17,225 |
| HCFCD P130-09-00 | Texas | Scour Critical — Countermeasures Installed | Fair | 1967 | 17,217 |
| Biscayne Canal C-8 | Florida | Scour Critical — Countermeasures Installed | Fair | 1964 | 17,200 |
| LITTLE RIVER | Connecticut | Scour Critical — Countermeasures Installed | Fair | 1934 | 17,200 |
| NORTH BR.NESHAMINY CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1939 | 17,187 |
| CROYS CREEK | Indiana | Scour Critical — Countermeasures Installed | Fair | 1966 | 17,165 |
| CONTOOCOOK RIVER | New Hampshire | Scour Critical — Countermeasures Installed | Fair | 1961 | 17,117 |
| KACHESS RIVER | Washington | Scour Critical — Countermeasures Installed | Poor | 1958 | 17,108 |
| ORTEGA RIVER | Florida | Scour Critical — Countermeasures Installed | Fair | 1952 | 17,100 |
| QUEBRADILLA CREEK | Puerto Rico | Scour Critical — Countermeasures Installed | Fair | 1964 | 17,100 |
| CLE ELUM RIVER | Washington | Scour Critical — Countermeasures Installed | Fair | 1949 | 17,089 |
| CLE ELUM RIVER | Washington | Scour Critical — Countermeasures Installed | Fair | 1962 | 17,089 |
| TROUT/MASCHELLAMAC CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Poor | 1874 | 17,059 |
| LYNCHES RIVER | South Carolina | Scour Critical — Countermeasures Installed | Fair | 1967 | 17,050 |
| LYNCHES RIVER | South Carolina | Scour Critical — Countermeasures Installed | Fair | 1967 | 17,050 |
| PLATEAU CREEK | Colorado | Scour Critical — Countermeasures Installed | Fair | 1965 | 17,000 |
| SOUTH CREEK | Florida | Scour Critical — Countermeasures Installed | Fair | 1928 | 17,000 |
| SNAKE RIVER;HEYBURN BR. | Idaho | Scour Critical — Countermeasures Installed | Fair | 1977 | 17,000 |
| PLATEAU CREEK R | Colorado | Scour Critical — Countermeasures Installed | Fair | 1958 | 17,000 |
| KALAMAZOO RIVER | Michigan | Scour Critical — Countermeasures Installed | Fair | 1994 | 17,000 |
| West Brook Canal | Florida | Scour Critical — Countermeasures Installed | Good | 1960 | 17,000 |
| STATE DRAIN | Michigan | Scour Critical — Countermeasures Installed | Fair | 1931 | 17,000 |
| ROGUE R & WHITE PINE TRL | Michigan | Scour Critical — Countermeasures Installed | Fair | 1977 | 16,978 |
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.