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
PAULINS KILL New Jersey Scour Critical — Countermeasures Installed Good 1931 5,501
FARM RIVER Connecticut Scour Critical — Countermeasures Installed Fair 1900 5,500
GILDER CREEK South Carolina Scour Critical — Countermeasures Installed Good 1970 5,500
BRUSHY CREEK South Carolina Scour Critical — Countermeasures Installed Fair 1987 5,500
BR. LITTLE CONTENTNEA CR North Carolina Scour Critical — Countermeasures Installed Fair 1956 5,500
MUD CREEK Wisconsin Scour Critical — Countermeasures Installed Fair 1932 5,500
MAGINA CREEK Puerto Rico Scour Critical — Countermeasures Installed Fair 1969 5,500
BOISE RIVER Idaho Scour Critical — Countermeasures Installed Fair 1932 5,500
BOISE RIVER Idaho Scour Critical — Countermeasures Installed Fair 1976 5,500
TEN MILE RIVER Connecticut Scour Critical — Countermeasures Installed Fair 1936 5,500
Branch of HONEY CREEK Indiana Scour Critical — Countermeasures Installed Fair 1919 5,500
WATER BENT TRAVERS POND Massachusetts Scour Critical — Countermeasures Installed Fair 1924 5,500
BIG SALT WASH Colorado Scour Critical — Countermeasures Installed Fair 1970 5,500
BIG SALT WASH Colorado Scour Critical — Countermeasures Installed Fair 1970 5,500
LITTLE SALT WASH Colorado Scour Critical — Countermeasures Installed Fair 1970 5,500
LITTLE SALT WASH Colorado Scour Critical — Countermeasures Installed Fair 1970 5,500
MORTON HALL DITCH Indiana Scour Critical — Countermeasures Installed Fair 1996 5,493
FISH CREEK Michigan Scour Critical — Countermeasures Installed Fair 1931 5,487
BUTTERNUT CREEK Michigan Scour Critical — Countermeasures Installed Fair 1940 5,487
PRAIRIE CREEK Michigan Scour Critical — Countermeasures Installed Fair 1953 5,487
PUSHAPATAPA CR Louisiana Scour Critical — Countermeasures Installed Good 1965 5,485
DRAIN Louisiana Scour Critical — Countermeasures Installed Fair 1965 5,485
DRAW Texas Scour Critical — Countermeasures Installed Fair 1949 5,482
TYLER DITCH Indiana Scour Critical — Countermeasures Installed Fair 1961 5,472
JAMES KRUCEK DITCH Indiana Scour Critical — Countermeasures Installed Fair 1961 5,472
Ash Swale Oregon Scour Critical — Countermeasures Installed Fair 1922 5,468
ST MARYS RIVER OVERFLOW Indiana Scour Critical — Countermeasures Installed Fair 1997 5,462
SEVENTEEN MILE CREEK Indiana Scour Critical — Countermeasures Installed Good 1997 5,462
BLACK RIVER Michigan Scour Critical — Countermeasures Installed Poor 1947 5,462
Cottonwood Wash Arizona Scour Critical — Countermeasures Installed Fair 1948 5,460
CLARKS RR PEMIGEWASSET R New Hampshire Scour Critical — Countermeasures Installed Good 1981 5,456
PETERS BROOK New Jersey Scour Critical — Countermeasures Installed Fair 1901 5,455
DECKER CREEK Pennsylvania Scour Critical — Countermeasures Installed Poor 1950 5,455
SOUTH MAYDE CREEK Texas Scour Critical — Countermeasures Installed Fair 1968 5,450
S Yamhill River Oregon Scour Critical — Countermeasures Installed Fair 1935 5,448
HICKMAN LATERAL DITCH Indiana Scour Critical — Countermeasures Installed Fair 1992 5,445
FOX SKIN BAYOU Louisiana Scour Critical — Countermeasures Installed Poor 1979 5,436
SCHOENECK CREEK Pennsylvania Scour Critical — Countermeasures Installed Poor 1942 5,435
WESTERN CREEK Indiana Scour Critical — Countermeasures Installed Fair 1932 5,417
BRANCH Tennessee Scour Critical — Countermeasures Installed Fair 1925 5,411
SILVER CREEK Texas Scour Critical — Countermeasures Installed Good 1997 5,408
BIRD CREEK Tennessee Scour Critical — Countermeasures Installed Good 1959 5,400
PRATT CREEK Wisconsin Scour Critical — Countermeasures Installed Fair 1964 5,400
DOCTOR PASS INLET Florida Scour Critical — Countermeasures Installed Good 1975 5,400
WHITING RIVER Connecticut Scour Critical — Countermeasures Installed Fair 1949 5,400
LITTLE CALUMET RIVER Indiana Scour Critical — Countermeasures Installed Fair 1972 5,400
SIMMONS CREEK South Carolina Scour Critical — Countermeasures Installed Fair 1967 5,400
PRAIRIE RIVER Michigan Scour Critical — Countermeasures Installed Fair 1931 5,400
MORGAN BROOK Connecticut Scour Critical — Countermeasures Installed Fair 1947 5,400
BRANCH BUSSERON CREEK Indiana Scour Critical — Countermeasures Installed Fair 1965 5,399

Scour Critical Bridges by State

States ranked by number of scour critical bridges.

StateScour CriticalUnaddressedCountermeasuresIneffective
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 — UnaddressedBridge is scour critical with no countermeasures installed. The foundation is vulnerable and no protective action has been taken.
Code 3 — Countermeasures InstalledProtective measures (riprap, sheet piling, etc.) have been installed to reduce scour risk, but the bridge remains classified as scour critical.
Code 6 — Countermeasures IneffectiveProtective 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.