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 |
|---|---|---|---|---|---|
| MATZ AVE RR DRAIN. DITCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1971 | 9,450 |
| SPRING GULLY | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1930 | 9,445 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1922 | 9,442 |
| HCFCD DITCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1960 | 9,430 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 1941 | 9,384 |
| DRAINAGE DITCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2010 | 9,382 |
| ROCK CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2000 | 9,366 |
| WHITE OAK BAYOU | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1987 | 9,360 |
| WHITE OAK BAYOU | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1987 | 9,360 |
| DONNA DRAIN | Texas | Scour Critical — Countermeasures Ineffective | Good | 1988 | 9,359 |
| LITTLE LIVE OAK CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1922 | 9,337 |
| JACKSON BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1952 | 9,317 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 1939 | 9,307 |
| SEABOURNE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1931 | 9,296 |
| OLD SIMS BAYOU | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1945 | 9,270 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2002 | 9,239 |
| E FORK CRYSTAL CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1941 | 9,237 |
| CLEAR CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1971 | 9,170 |
| LACY CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1938 | 9,132 |
| LACY CREEK RELIEF | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1938 | 9,132 |
| BIG SANDY CREEK BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1934 | 9,071 |
| Swan Creek (Relief) | Alabama | Scour Critical — Countermeasures Ineffective | Good | 2023 | 9,052 |
| Swan Creek (MC) | Alabama | Scour Critical — Countermeasures Ineffective | Good | 2023 | 9,052 |
| LAKE WOODLANDS | Texas | Scour Critical — Countermeasures Ineffective | Good | 2000 | 9,026 |
| STEWARTS CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2011 | 9,010 |
| CANEY CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2011 | 9,010 |
| MAYDE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2014 | 9,000 |
| WATER PAWTUCKET CANAL | Massachusetts | Scour Critical — Countermeasures Ineffective | Good | 1852 | 9,000 |
| CLAY RD & MAYDE CRK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2014 | 9,000 |
| MAYDE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2014 | 9,000 |
| CLAY RD & MAYDE CRK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2014 | 9,000 |
| DELAWARE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1934 | 9,000 |
| FRENCH CREEK | Ohio | Scour Critical — Countermeasures Ineffective | Good | 2023 | 8,955 |
| VOGEL CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1998 | 8,950 |
| GUADALUPE RIVER | Texas | Scour Critical — Countermeasures Ineffective | Good | 2005 | 8,950 |
| VOGEL CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1998 | 8,950 |
| FILBIN CREEK | South Carolina | Scour Critical — Countermeasures Ineffective | Fair | 1992 | 8,900 |
| LITTLE VINCE BAYOU | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1981 | 8,850 |
| PILLOT GULLY | Texas | Scour Critical — Countermeasures Ineffective | Good | 2004 | 8,840 |
| ROCK CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1934 | 8,815 |
| SABINAL RIVER | Texas | Scour Critical — Countermeasures Ineffective | Good | 1932 | 8,800 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1934 | 8,791 |
| HCFCD DITCH K140-04-00 | Texas | Scour Critical — Countermeasures Ineffective | Good | 2004 | 8,780 |
| OJO DE AGUA CRK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1969 | 8,778 |
| OJO DE AGUA CRK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1981 | 8,778 |
| CANEY CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1993 | 8,732 |
| W BRANCH LIVE OAK CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1951 | 8,716 |
| PARKER CREEK BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1951 | 8,716 |
| SPRING CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1986 | 8,694 |
| RANGE CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1986 | 8,694 |
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.