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 |
|---|---|---|---|---|---|
| SUKKWAN STRAIT | Alaska | Scour Critical — Countermeasures Ineffective | Poor | 1970 | 5 |
| BRANCH DENTON CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1996 | 5 |
| WHITE RIVER | Utah | Scour Critical — Countermeasures Ineffective | Poor | 2000 | 5 |
| WEST CANAL | Washington | Scour Critical — Countermeasures Ineffective | Good | 1946 | 5 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 2008 | 4 |
| Canal # 2/Big Bayou | Arkansas | Scour Critical — Countermeasures Ineffective | Fair | 1970 | 4 |
| MUDDY CREEK | Utah | Scour Critical — Countermeasures Ineffective | Good | 2023 | 3 |
| BURGIS CREEK | South Carolina | Scour Critical — Countermeasures Ineffective | Good | 2019 | 3 |
| TRIB CHILDRESS CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1935 | 2 |
| BEAVER CREEK | Texas | Scour Critical — Countermeasures Ineffective | Poor | 1919 | 2 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 2006 | 2 |
| PINE CREEK | Minnesota | Scour Critical — Countermeasures Ineffective | Fair | 2007 | 1 |
| SHOTLEY BROOK | Minnesota | Scour Critical — Countermeasures Ineffective | Poor | 1917 | 1 |
| ST AUGUSTA CREEK | Minnesota | Scour Critical — Countermeasures Ineffective | Poor | 1925 | 1 |
| TROUT CREEK | Minnesota | Scour Critical — Countermeasures Ineffective | Good | 2022 | 1 |
| E BR BEAVER RIVER | Minnesota | Scour Critical — Countermeasures Ineffective | Good | 2023 | 1 |
| PARADISE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2005 | 1 |
| SERRANO CREEK | California | Scour Critical — Countermeasures Ineffective | Good | 2024 | 1 |
| FISHROCK CREEK | North Carolina | Scour Critical — Countermeasures Ineffective | Poor | 1960 | 1 |
| BONES CREEK | North Carolina | Scour Critical — Countermeasures Ineffective | Poor | 1960 | 1 |
| ROCKFISH CREEK | North Carolina | Scour Critical — Countermeasures Ineffective | Poor | 1960 | 1 |
| JUMIPER CREEK | North Carolina | Scour Critical — Countermeasures Ineffective | Poor | 1960 | 1 |
| ROCKFISH CREEK | North Carolina | Scour Critical — Countermeasures Ineffective | Poor | 1960 | 1 |
| HOURSE CREEK | North Carolina | Scour Critical — Countermeasures Ineffective | Fair | 1960 | 1 |
| MCPHERSON CREEK | North Carolina | Scour Critical — Countermeasures Ineffective | Fair | 1960 | 1 |
| CALF BRANCH | North Carolina | Scour Critical — Countermeasures Ineffective | Poor | 1960 | 1 |
| SILVER RUN | North Carolina | Scour Critical — Countermeasures Ineffective | Poor | 1960 | 1 |
| BONES CREEK | North Carolina | Scour Critical — Countermeasures Ineffective | Fair | 1960 | 1 |
| FLAT CREEK | North Carolina | Scour Critical — Countermeasures Ineffective | Poor | 1960 | 1 |
| ROCKFISH CREEK | North Carolina | Scour Critical — Countermeasures Ineffective | Poor | 1960 | 1 |
| ROCKFISH CREEK | North Carolina | Scour Critical — Countermeasures Ineffective | Good | 2015 | 1 |
| STREAM - HAMILTON 50R36 | Alaska | Scour Critical — Countermeasures Ineffective | Fair | 1983 | — |
| TRENTON CHANNEL | Michigan | Scour Critical — Countermeasures Ineffective | Fair | 1913 | — |
| WATER NORTHERN CANAL | Massachusetts | Scour Critical — Countermeasures Ineffective | Poor | 1848 | — |
| WATER DRAINAGE | Massachusetts | Scour Critical — Countermeasures Ineffective | Good | 2004 | — |
| BLACK RIVER | New York | Scour Critical — Countermeasures Ineffective | Good | 2024 | — |
| SLOUGH | California | Scour Critical — Countermeasures Ineffective | Poor | 1945 | — |
| SKAGIT RIVER | Washington | Scour Critical — Countermeasures Ineffective | Fair | 1940 | — |
| ENGLISH BROOK 9 9 1710 | New York | Scour Critical — Countermeasures Ineffective | Good | 2024 | — |
| Plattekill Creek | New York | Scour Critical — Countermeasures Ineffective | Good | 2024 | — |
| Mud Creek | New York | Scour Critical — Countermeasures Ineffective | Good | 2024 | — |
| PUTNAM CREEK | New York | Scour Critical — Countermeasures Ineffective | Good | 2024 | — |
| Stephens Brook | New York | Scour Critical — Countermeasures Ineffective | Fair | 1931 | — |
| Mud Creek | New York | Scour Critical — Countermeasures Ineffective | Fair | 2024 | — |
| UNKNOWN STREAM | New York | Scour Critical — Countermeasures Ineffective | Fair | 1990 | — |
| East Branch Sandy Creek | New York | Scour Critical — Countermeasures Ineffective | Poor | 1958 | — |
| SHELDRAKE RIVER | New York | Scour Critical — Countermeasures Ineffective | Good | 2024 | — |
| Randalls Island | New York | Scour Critical — Countermeasures Ineffective | Good | 2024 | — |
| Sulphur Creek | New York | Scour Critical — Countermeasures Ineffective | Good | 2018 | — |
| Sulphur Creek | New York | Scour Critical — Countermeasures Ineffective | Good | 2018 | — |
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.