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 |
|---|---|---|---|---|---|
| TURNERS CREEK | Florida | Scour Critical — Countermeasures Installed | Fair | 1963 | 15,000 |
| WATER EAST RIVER | Massachusetts | Scour Critical — Countermeasures Installed | Fair | 1914 | 15,000 |
| FRANK & POET DRAIN | Michigan | Scour Critical — Countermeasures Installed | Fair | 1936 | 14,984 |
| BRANCH PENNYPACK CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1967 | 14,968 |
| ROCKAWAY RIVER | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1954 | 14,953 |
| SEEKONK RVR TAFT S | Rhode Island | Scour Critical — Countermeasures Installed | Fair | 1877 | 14,948 |
| PINE CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1977 | 14,925 |
| GRAND RIVER & MARKET RD | Michigan | Scour Critical — Countermeasures Installed | Fair | 1959 | 14,899 |
| GRAND RIVER & MARKET ST | Michigan | Scour Critical — Countermeasures Installed | Fair | 1959 | 14,899 |
| RED RUN DRAIN | Michigan | Scour Critical — Countermeasures Installed | Poor | 1985 | 14,852 |
| FELLOWS CREEK | Michigan | Scour Critical — Countermeasures Installed | Poor | 1930 | 14,842 |
| MILL-RACE CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1929 | 14,824 |
| ECORSE CREEK | Michigan | Scour Critical — Countermeasures Installed | Fair | 1977 | 14,820 |
| BRANCH PENNYPACK CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1941 | 14,809 |
| BRANCH DELAWARE RIVER | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1942 | 14,803 |
| LITTLE RIVER | Connecticut | Scour Critical — Countermeasures Installed | Fair | 1933 | 14,800 |
| BRUSH HEAP CREEK | Indiana | Scour Critical — Countermeasures Installed | Fair | 1974 | 14,800 |
| AIRPORT SLOUGH | Nevada | Scour Critical — Countermeasures Installed | Fair | 1965 | 14,800 |
| BRONX RIVER | New York | Scour Critical — Countermeasures Installed | Fair | 1923 | 14,760 |
| WHITE RIVER | Indiana | Scour Critical — Countermeasures Installed | Fair | 1936 | 14,760 |
| SCHUYLKILL RIV;NSRC;ROAD | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1924 | 14,759 |
| NAPA RIVER | California | Scour Critical — Countermeasures Installed | Fair | 1960 | 14,755 |
| PILARCITOS CREEK | California | Scour Critical — Countermeasures Installed | Good | 1954 | 14,750 |
| WACCAMAW RIVER | South Carolina | Scour Critical — Countermeasures Installed | Fair | 1986 | 14,750 |
| PILARCITOS CREEK | California | Scour Critical — Countermeasures Installed | Fair | 1954 | 14,750 |
| TROUBLESOME CREEK | North Carolina | Scour Critical — Countermeasures Installed | Fair | 1968 | 14,750 |
| WACCAMAW RIVER | South Carolina | Scour Critical — Countermeasures Installed | Fair | 1986 | 14,750 |
| TEN MILE RIVER | Rhode Island | Scour Critical — Countermeasures Installed | Fair | 1921 | 14,747 |
| PINE RUN CREEK | Michigan | Scour Critical — Countermeasures Installed | Fair | 1915 | 14,723 |
| TEMESCAL WASH | California | Scour Critical — Countermeasures Installed | Fair | 1983 | 14,721 |
| GUN RIVER | Michigan | Scour Critical — Countermeasures Installed | Fair | 1960 | 14,700 |
| GUN RIVER | Michigan | Scour Critical — Countermeasures Installed | Fair | 1960 | 14,700 |
| CATAÑO CREEK | Puerto Rico | Scour Critical — Countermeasures Installed | Fair | 1928 | 14,700 |
| GURABO RIVER KM 20.41 | Puerto Rico | Scour Critical — Countermeasures Installed | Fair | 1955 | 14,700 |
| TRIB.WILLOW CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1955 | 14,685 |
| PECKMAN RIVER | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1913 | 14,684 |
| ABITA RIVER | Louisiana | Scour Critical — Countermeasures Installed | Good | 1975 | 14,668 |
| PROVO RIVER | Utah | Scour Critical — Countermeasures Installed | Fair | 1960 | 14,608 |
| MERCADO CREEK | Puerto Rico | Scour Critical — Countermeasures Installed | Poor | 1952 | 14,600 |
| LITTLE RIVER | Connecticut | Scour Critical — Countermeasures Installed | Fair | 1926 | 14,600 |
| BR.LITTLE NESHAMINY CR. | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1923 | 14,595 |
| BYRAM RIVER | New York | Scour Critical — Countermeasures Installed | Poor | 1926 | 14,570 |
| PRAIRIE CREEK | Indiana | Scour Critical — Countermeasures Installed | Fair | 1959 | 14,559 |
| KALIHI STRM | Hawaii | Scour Critical — Countermeasures Installed | Fair | 1927 | 14,551 |
| Middle Creek Ash Creek | Oregon | Scour Critical — Countermeasures Installed | Fair | 1954 | 14,546 |
| NONCONNAH CREEK | Tennessee | Scour Critical — Countermeasures Installed | Fair | 1980 | 14,539 |
| PRAIRIE CREEK | Indiana | Scour Critical — Countermeasures Installed | Fair | 1951 | 14,533 |
| CRUM CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1949 | 14,523 |
| SAN JACINTO RIVER | Texas | Scour Critical — Countermeasures Installed | Fair | 1968 | 14,511 |
| LITTLE NORTHEAST | North Carolina | Scour Critical — Countermeasures Installed | Fair | 1994 | 14,500 |
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.