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
Brawley Wash Arizona Scour Critical — Countermeasures Installed Poor 1960 3,531
BIG QUILCENE RIVER Washington Scour Critical — Countermeasures Installed Poor 1936 3,525
WESTERN RUN Maryland Scour Critical — Countermeasures Installed Fair 1893 3,524
Fine Wash Arizona Scour Critical — Countermeasures Installed Fair 1932 3,521
SUCKER CREEK Michigan Scour Critical — Countermeasures Installed Fair 1967 3,520
MIDDLE FK COQUILLE RIVER Oregon Scour Critical — Countermeasures Installed Fair 1984 3,518
LICK CREEK Tennessee Scour Critical — Countermeasures Installed Fair 1966 3,516
Canal 092 Florida Scour Critical — Countermeasures Installed Good 1941 3,515
Canal 088 Florida Scour Critical — Countermeasures Installed Fair 1949 3,515
Canal 087 Florida Scour Critical — Countermeasures Installed Fair 1949 3,515
Canal 086 Florida Scour Critical — Countermeasures Installed Good 1955 3,515
WALNUT RIVER Kansas Scour Critical — Countermeasures Installed Fair 1953 3,509
WALNUT RIVER DRAINAGE Kansas Scour Critical — Countermeasures Installed Fair 1953 3,509
BIRCH CREEK OVERFLOW Indiana Scour Critical — Countermeasures Installed Fair 1986 3,508
Icehouse Canyon Arizona Scour Critical — Countermeasures Installed Good 1920 3,504
Normandy Waterway Florida Scour Critical — Countermeasures Installed Good 1983 3,503
JOHNSON CREEK Oregon Scour Critical — Countermeasures Installed Fair 1938 3,502
FORESTER CREEK Michigan Scour Critical — Countermeasures Installed Fair 1934 3,500
TRIB. TO ROCKY RIVER South Carolina Scour Critical — Countermeasures Installed Good 1992 3,500
WARRIOR RIVER RELIEF Alabama Scour Critical — Countermeasures Installed Fair 1927 3,500
SAMMY SWAMP CREEK South Carolina Scour Critical — Countermeasures Installed Fair 1946 3,500
WATER N NASHUA RIVER Massachusetts Scour Critical — Countermeasures Installed Fair 1900 3,500
LA MINA CREEK Puerto Rico Scour Critical — Countermeasures Installed Fair 1981 3,500
GROVE CREEK South Carolina Scour Critical — Countermeasures Installed Fair 1976 3,500
MUSCATINE SLOUGH Iowa Scour Critical — Countermeasures Installed Good 2002 3,500
TCHOUTACABOUFFA RIVER Mississippi Scour Critical — Countermeasures Installed Fair 1998 3,500
MUSCATINE SLOUGH Iowa Scour Critical — Countermeasures Installed Good 2002 3,500
GARCIA CREEK Puerto Rico Scour Critical — Countermeasures Installed Fair 1941 3,500
FRIENDSHIP CREEK New Jersey Scour Critical — Countermeasures Installed Fair 1900 3,494
SALT CREEK Washington Scour Critical — Countermeasures Installed Fair 1952 3,493
INDIAN CREEK Indiana Scour Critical — Countermeasures Installed Fair 1984 3,490
SAND CREEK Georgia Scour Critical — Countermeasures Installed Good 1976 3,490
NESTUCCA RIVER Oregon Scour Critical — Countermeasures Installed Fair 1973 3,489
STEWART CREEK Kansas Scour Critical — Countermeasures Installed Fair 1953 3,488
STEWART CREEK DRAINAGE Kansas Scour Critical — Countermeasures Installed Fair 1953 3,488
Calapooia Bottoms No. 5 Oregon Scour Critical — Countermeasures Installed Fair 1963 3,487
JOHNSON BRANCH Delaware Scour Critical — Countermeasures Installed Fair 1947 3,486
SPRING BRANCH Tennessee Scour Critical — Countermeasures Installed Fair 1952 3,482
GRASSY COVE CREEK Tennessee Scour Critical — Countermeasures Installed Fair 1951 3,482
LICK CREEK Tennessee Scour Critical — Countermeasures Installed Fair 1948 3,482
GRASSY COVE CREEK Tennessee Scour Critical — Countermeasures Installed Fair 1951 3,482
CHOCTAW CREEK Texas Scour Critical — Countermeasures Installed Fair 1994 3,479
EAST BR BRANDYWINE CREEK Pennsylvania Scour Critical — Countermeasures Installed Fair 1931 3,479
CASS RIVER Michigan Scour Critical — Countermeasures Installed Fair 1957 3,478
LITTLE BAYOU Florida Scour Critical — Countermeasures Installed Fair 1961 3,477
BLUE JACKET CREEK Ohio Scour Critical — Countermeasures Installed Good 1965 3,475
Wolf Creek Pennsylvania Scour Critical — Countermeasures Installed Poor 1981 3,473
BOONE CREEK Louisiana Scour Critical — Countermeasures Installed Fair 1991 3,472
DORCHEAT BAYOU RELIEF Louisiana Scour Critical — Countermeasures Installed Fair 1982 3,472
DORCHEAT BAYOU Louisiana Scour Critical — Countermeasures Installed Fair 1981 3,472

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.