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 |
|---|---|---|---|---|---|
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 1963 | 400 |
| LOWER CREEK | West Virginia | Scour Critical — Countermeasures Ineffective | Fair | 1931 | 400 |
| DERBY LAKE DRAIN | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1990 | 400 |
| LAUREL CREEK | West Virginia | Scour Critical — Countermeasures Ineffective | Fair | 1975 | 400 |
| Seabourne Crk | Texas | Scour Critical — Countermeasures Ineffective | Good | 2023 | 400 |
| HCFCD DITCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2001 | 400 |
| Little Owl Creek | Texas | Scour Critical — Countermeasures Ineffective | Good | 2023 | 400 |
| SLOUGH CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2003 | 399 |
| MUSTANG CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1965 | 397 |
| TRIB OF HICKORY CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1955 | 396 |
| HICKORY CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2016 | 396 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 1943 | 395 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 1943 | 395 |
| PARADISE CRK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1956 | 395 |
| MERRITTS CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1950 | 394 |
| EMBLEM CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1950 | 394 |
| SALT CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1927 | 392 |
| BEAVER BROOK | New York | Scour Critical — Countermeasures Ineffective | Good | 2024 | 392 |
| TIMBER CRK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1967 | 390 |
| WATER WETLAND | Massachusetts | Scour Critical — Countermeasures Ineffective | Good | 2015 | 390 |
| W CANEY CRK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1967 | 390 |
| LITTLE MISSOURI RIVER | Arkansas | Scour Critical — Countermeasures Ineffective | Fair | 1979 | 390 |
| POND CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1975 | 390 |
| Draw | Texas | Scour Critical — Countermeasures Ineffective | Good | 2008 | 389 |
| LINDSEY CRK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1958 | 389 |
| CYPRESS CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1969 | 389 |
| RICHLAND CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1962 | 388 |
| JOHNS CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1962 | 387 |
| FREEMAN BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1966 | 384 |
| FREEMAN CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2003 | 384 |
| TWIN HOLLOW CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1938 | 384 |
| LITTLE WHITE RCK CRK REL | Texas | Scour Critical — Countermeasures Ineffective | Good | 1995 | 382 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1959 | 379 |
| SANDY CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1954 | 379 |
| TIDWELL CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1988 | 378 |
| W FORK BRIAR BR | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1952 | 377 |
| MCWRIGHT BR | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1952 | 377 |
| EAST CADDO CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1992 | 377 |
| ELK CREEK | Washington | Scour Critical — Countermeasures Ineffective | Fair | 1964 | 375 |
| KINGS CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1935 | 375 |
| PLUM CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1959 | 374 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1959 | 374 |
| RATLIFF BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Good | 1985 | 373 |
| MARTIN CRK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1948 | 370 |
| FLINT CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1964 | 369 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1964 | 369 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1963 | 368 |
| NOBLE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1963 | 368 |
| BEAR HEAD CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1955 | 367 |
| HOLDEN BR | Texas | Scour Critical — Countermeasures Ineffective | Good | 1962 | 364 |
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.