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
SLOUGH Louisiana Scour Critical — Countermeasures Installed Fair 1976 2,958
W BR WAISKA RIVER Michigan Scour Critical — Countermeasures Installed Fair 1975 2,956
LITTLE NESHAMINY CREEK Pennsylvania Scour Critical — Countermeasures Installed Fair 1959 2,952
LITTLE MULBERRYCREEKREIL Alabama Scour Critical — Countermeasures Installed Fair 1939 2,950
GUAYNABO RIVER Puerto Rico Scour Critical — Countermeasures Installed Fair 1983 2,950
HILLS. BAY & BAYSHORE B. Florida Scour Critical — Countermeasures Installed Fair 1927 2,950
CHAMPION CREEK Pennsylvania Scour Critical — Countermeasures Installed Fair 1942 2,947
ROGUE RIVER Michigan Scour Critical — Countermeasures Installed Good 1963 2,946
ELDER RUN Pennsylvania Scour Critical — Countermeasures Installed Fair 1952 2,942
Dry Wash Arizona Scour Critical — Countermeasures Installed Fair 1932 2,940
Palmer Creek Oregon Scour Critical — Countermeasures Installed Fair 1984 2,939
SWAMP BROOK CREEK Pennsylvania Scour Critical — Countermeasures Installed Poor 1958 2,932
SARDINE CREEK Oregon Scour Critical — Countermeasures Installed Good 1938 2,931
BUCKHEAD CREEK Georgia Scour Critical — Countermeasures Installed Good 1988 2,930
HAZLE CREEK Pennsylvania Scour Critical — Countermeasures Installed Poor 1961 2,928
PINE CREEK Pennsylvania Scour Critical — Countermeasures Installed Fair 1915 2,927
SANDY BOIS DARC Arkansas Scour Critical — Countermeasures Installed Fair 1930 2,927
S FK SCAPPOOSE CREEK Oregon Scour Critical — Countermeasures Installed Poor 1957 2,926
Mid. Fk. Coquille River Oregon Scour Critical — Countermeasures Installed Fair 1962 2,925
SANDY CREEK Oregon Scour Critical — Countermeasures Installed Fair 1979 2,925
COQUILLE RIVER Oregon Scour Critical — Countermeasures Installed Fair 1964 2,925
COQUILLE RIVER Oregon Scour Critical — Countermeasures Installed Fair 1964 2,925
NORTH COTTONWOOD RIVER Kansas Scour Critical — Countermeasures Installed Good 1987 2,923
Tenmile Creek Oregon Scour Critical — Countermeasures Installed Fair 1931 2,922
CASS RIVER Michigan Scour Critical — Countermeasures Installed Fair 1966 2,920
PINE CREEK Pennsylvania Scour Critical — Countermeasures Installed Poor 1929 2,917
CHERRY CREEK Pennsylvania Scour Critical — Countermeasures Installed Fair 1929 2,917
EAST BRANCH RED CLAY CR. Pennsylvania Scour Critical — Countermeasures Installed Fair 1923 2,912
Climas Wash Arizona Scour Critical — Countermeasures Installed Fair 1984 2,912
LYNN CREEK Indiana Scour Critical — Countermeasures Installed Fair 1955 2,910
BEAVER MEADOW CREEK Indiana Scour Critical — Countermeasures Installed Fair 1955 2,910
Willow Creek Oregon Scour Critical — Countermeasures Installed Fair 1964 2,909
OVER INLET CREEK Pennsylvania Scour Critical — Countermeasures Installed Poor 1934 2,904
Stockton Wash Arizona Scour Critical — Countermeasures Installed Fair 1938 2,901
JOHNSON CREEK Oregon Scour Critical — Countermeasures Installed Poor 1930 2,901
DEEP CREEK Washington Scour Critical — Countermeasures Installed Fair 1958 2,901
HAY CREEK Colorado Scour Critical — Countermeasures Installed Fair 1930 2,901
DEEP CREEK North Carolina Scour Critical — Countermeasures Installed Fair 1965 2,900
HINTON CREEK North Carolina Scour Critical — Countermeasures Installed Poor 1955 2,900
CAMP CREEK CANAL Mississippi Scour Critical — Countermeasures Installed Good 1992 2,900
NORTH FORK CATAWBA RIVER North Carolina Scour Critical — Countermeasures Installed Fair 1938 2,900
BIG CEDAR RIVER Michigan Scour Critical — Countermeasures Installed Fair 1952 2,900
MASHEL RIVER Washington Scour Critical — Countermeasures Installed Fair 1937 2,900
ROARING CREEK West Virginia Scour Critical — Countermeasures Installed Poor 1919 2,900
DAN RIVER North Carolina Scour Critical — Countermeasures Installed Poor 1955 2,900
BEAVERDAM CREEK South Carolina Scour Critical — Countermeasures Installed Good 1987 2,900
MILL RIVER Connecticut Scour Critical — Countermeasures Installed Poor 1940 2,900
CARSON RVR Nevada Scour Critical — Countermeasures Installed Fair 1987 2,900
FAIRFOREST CREEK South Carolina Scour Critical — Countermeasures Installed Poor 1987 2,900
KENAI RIVER (SCHOONERS) Alaska Scour Critical — Countermeasures Installed Fair 1954 2,900

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.