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 |
|---|---|---|---|---|---|
| Trib of Willow Creek | Texas | Scour Critical — Countermeasures Ineffective | Good | 2021 | 6,407 |
| BEASLEY BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Good | 1999 | 6,390 |
| HCFCD DITCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1977 | 6,381 |
| BUFFALO BAYOU | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1931 | 6,380 |
| 1ST ST & PREMONT DRAIN | Texas | Scour Critical — Countermeasures Ineffective | Good | 2022 | 6,368 |
| CHACON CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1939 | 6,367 |
| CentennialPkwyChannel W | Nevada | Scour Critical — Countermeasures Ineffective | Good | 2018 | 6,350 |
| SPRING BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1971 | 6,319 |
| Honey Spring Branch | Texas | Scour Critical — Countermeasures Ineffective | Good | 1975 | 6,319 |
| HCFCD DITCH | Texas | Scour Critical — Countermeasures Ineffective | Good | 2000 | 6,310 |
| HCFCD DITCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 2000 | 6,310 |
| MAIN FLOODWAY PILOT CH | Texas | Scour Critical — Countermeasures Ineffective | Good | 1996 | 6,309 |
| HCFCD A-121-00-00 | Texas | Scour Critical — Countermeasures Ineffective | Good | 2006 | 6,294 |
| EAST FORK CRYSTAL CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1989 | 6,286 |
| COON CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1934 | 6,265 |
| BIG BRUSHY CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1934 | 6,265 |
| BEE BAYOU | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1934 | 6,265 |
| GREENS BAYOU TRIB | Texas | Scour Critical — Countermeasures Ineffective | Good | 2011 | 6,263 |
| GREENS BAYOU | Texas | Scour Critical — Countermeasures Ineffective | Good | 2013 | 6,263 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Good | 1966 | 6,253 |
| LAKE COLEMAN DRAIN | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1974 | 6,244 |
| Coon Creek | Texas | Scour Critical — Countermeasures Ineffective | Good | 1999 | 6,200 |
| DRAINAGE DITCH | Texas | Scour Critical — Countermeasures Ineffective | Good | 1989 | 6,197 |
| EAST MAIN DRAIN | Texas | Scour Critical — Countermeasures Ineffective | Good | 2007 | 6,159 |
| EAST MAIN DRAIN | Texas | Scour Critical — Countermeasures Ineffective | Good | 2007 | 6,159 |
| HICKORY CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1969 | 6,143 |
| TOWN CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 1982 | 6,126 |
| ARROYO COLORADO | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1953 | 6,072 |
| BIG SANDY CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1934 | 6,060 |
| DRAINAGE DITCH | Texas | Scour Critical — Countermeasures Ineffective | Good | 1999 | 6,055 |
| DRY CREEK | Georgia | Scour Critical — Countermeasures Ineffective | Good | 2023 | 6,040 |
| DRY CREEK | Georgia | Scour Critical — Countermeasures Ineffective | Good | 2023 | 6,040 |
| HCFCD DITCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1966 | 6,035 |
| HCFCD DITCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1982 | 6,035 |
| BUFFALO HOLLOW | Texas | Scour Critical — Countermeasures Ineffective | Good | 1988 | 6,014 |
| POST OAK CREEK | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1945 | 6,014 |
| DRAW | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1973 | 6,007 |
| ELM CREEK RELIEF | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1938 | 6,005 |
| METZLER GULLY | Texas | Scour Critical — Countermeasures Ineffective | Good | 1991 | 6,000 |
| TELGE RD WILLOW CREEK | Texas | Scour Critical — Countermeasures Ineffective | Good | 2015 | 6,000 |
| COW BAYOU | Texas | Scour Critical — Countermeasures Ineffective | Good | 2008 | 6,000 |
| COW BAYOU | Texas | Scour Critical — Countermeasures Ineffective | Good | 2008 | 6,000 |
| DRAINAGE DITCH | Texas | Scour Critical — Countermeasures Ineffective | Good | 1975 | 6,000 |
| PROTECTION LEVEE DITCH | Texas | Scour Critical — Countermeasures Ineffective | Good | 1993 | 5,998 |
| DRAINAGE DITCH | Texas | Scour Critical — Countermeasures Ineffective | Fair | 1965 | 5,995 |
| POST OAK CRK TRIB | Texas | Scour Critical — Countermeasures Ineffective | Good | 1962 | 5,968 |
| GREENS BAYOU | Texas | Scour Critical — Countermeasures Ineffective | Good | 1981 | 5,961 |
| WILSON CREEK TRIBUTARY | Texas | Scour Critical — Countermeasures Ineffective | Good | 1982 | 5,943 |
| LONG BRANCH | Texas | Scour Critical — Countermeasures Ineffective | Good | 1938 | 5,927 |
| DONNA DRAIN | Texas | Scour Critical — Countermeasures Ineffective | Good | 1967 | 5,914 |
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.