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 |
|---|---|---|---|---|---|
| BEANBLOSSOM OVERFLOW | Indiana | Scour Critical — Countermeasures Installed | Good | 1972 | 15,560 |
| BRANCH OF CLARKS CREEK | Indiana | Scour Critical — Countermeasures Installed | Fair | 1940 | 15,550 |
| BRANCH OF CLARKS CREEK | Indiana | Scour Critical — Countermeasures Installed | Fair | 1940 | 15,550 |
| HO-HO-KUS BROOK | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1957 | 15,522 |
| BEANBLOSSOM OVERFLOW | Indiana | Scour Critical — Countermeasures Installed | Fair | 1946 | 15,510 |
| Caney Crk | Texas | Scour Critical — Countermeasures Installed | Good | 2022 | 15,500 |
| FANCY BLUFF CREEK | Georgia | Scour Critical — Countermeasures Installed | Good | 1997 | 15,500 |
| POCASSET RIVER | Rhode Island | Scour Critical — Countermeasures Installed | Good | 2019 | 15,500 |
| MEADE ST. DRAINAGE | South Dakota | Scour Critical — Countermeasures Installed | Good | 1964 | 15,500 |
| FIVE MILE CREEK | Texas | Scour Critical — Countermeasures Installed | Fair | 1957 | 15,462 |
| TOBY CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1941 | 15,449 |
| TOBY CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Poor | 1941 | 15,449 |
| PEQUANNOCK RIVER | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1969 | 15,440 |
| HASKELL SLOUGH | Washington | Scour Critical — Countermeasures Installed | Fair | 1957 | 15,411 |
| BRUSH HEAP CREEK | Indiana | Scour Critical — Countermeasures Installed | Fair | 1974 | 15,403 |
| Pudding River | Oregon | Scour Critical — Countermeasures Installed | Fair | 1922 | 15,402 |
| INTRACOASTAL WATERWAY | Florida | Scour Critical — Countermeasures Installed | Fair | 1981 | 15,400 |
| BIG FOSSIL CREEK | Texas | Scour Critical — Countermeasures Installed | Fair | 1990 | 15,396 |
| LITTLE RICHLAND CREEK | Tennessee | Scour Critical — Countermeasures Installed | Fair | 1960 | 15,352 |
| LITTLE RICHLAND CREEK | Tennessee | Scour Critical — Countermeasures Installed | Fair | 1960 | 15,352 |
| CLINTON RIVER | Michigan | Scour Critical — Countermeasures Installed | Fair | 1959 | 15,351 |
| Tamiami Canal C-4 | Florida | Scour Critical — Countermeasures Installed | Good | 1965 | 15,350 |
| FLINT RIVER | Michigan | Scour Critical — Countermeasures Installed | Fair | 1967 | 15,328 |
| WEST FK WHITE LICK CREEK | Indiana | Scour Critical — Countermeasures Installed | Fair | 1940 | 15,322 |
| CARTERSBURG BRANCH | Indiana | Scour Critical — Countermeasures Installed | Fair | 1940 | 15,322 |
| CROSS BAYOU | Louisiana | Scour Critical — Countermeasures Installed | Good | 1983 | 15,302 |
| BATTLE CREEK RIVER | Michigan | Scour Critical — Countermeasures Installed | Fair | 1966 | 15,300 |
| RABBIT RIVER | Michigan | Scour Critical — Countermeasures Installed | Fair | 1957 | 15,300 |
| B-136 X COLUMBIA SLOUGH | Oregon | Scour Critical — Countermeasures Installed | Fair | 1992 | 15,271 |
| South Yamhill River | Oregon | Scour Critical — Countermeasures Installed | Fair | 1963 | 15,252 |
| SYCAMORE RUN | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1926 | 15,217 |
| BOIS DE SIOUX RIVER | North Dakota | Scour Critical — Countermeasures Installed | Fair | 1929 | 15,200 |
| CANNON RIVER | Minnesota | Scour Critical — Countermeasures Installed | Fair | 1954 | 15,200 |
| JENKINS BRANCH | Texas | Scour Critical — Countermeasures Installed | Fair | 1983 | 15,176 |
| WOONASQUATUCKET RIVER | Rhode Island | Scour Critical — Countermeasures Installed | Fair | 1994 | 15,175 |
| Bowers Slough | Oregon | Scour Critical — Countermeasures Installed | Fair | 1964 | 15,140 |
| MT DESERT NARROWS | Maine | Scour Critical — Countermeasures Installed | Fair | 1958 | 15,122 |
| SLOUGH & CNTY RD | Washington | Scour Critical — Countermeasures Installed | Fair | 1947 | 15,105 |
| BRANCH RIVER | Rhode Island | Scour Critical — Countermeasures Installed | Poor | 1919 | 15,100 |
| DUCK CREEK | Texas | Scour Critical — Countermeasures Installed | Good | 1972 | 15,097 |
| EDWARDS RUN | New Jersey | Scour Critical — Countermeasures Installed | Fair | 1920 | 15,089 |
| CAPE ISLAND CREEK | New Jersey | Scour Critical — Countermeasures Installed | Poor | 1927 | 15,085 |
| RAILROAD DRAIN | Michigan | Scour Critical — Countermeasures Installed | Fair | 1950 | 15,061 |
| CREVE COEUR CR | Missouri | Scour Critical — Countermeasures Installed | Fair | 1968 | 15,056 |
| STEVENS CREEK | California | Scour Critical — Countermeasures Installed | Fair | 1922 | 15,041 |
| LITTLE BLACK CREEK | Pennsylvania | Scour Critical — Countermeasures Installed | Fair | 1928 | 15,032 |
| JENKINS CREEK | Washington | Scour Critical — Countermeasures Installed | Fair | 1929 | 15,015 |
| BOULDER CREEK | Colorado | Scour Critical — Countermeasures Installed | Poor | 1938 | 15,000 |
| WATER EAST RIVER | Massachusetts | Scour Critical — Countermeasures Installed | Fair | 1914 | 15,000 |
| SNAKE RIVER;HEYBURN BR. | Idaho | Scour Critical — Countermeasures Installed | Fair | 1955 | 15,000 |
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.