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
SPRING CREEK Texas Scour Critical — Countermeasures Installed Good 1984 16,126
GRAND RIVER Michigan Scour Critical — Countermeasures Installed Poor 1955 16,125
PASCACK BROOK New Jersey Scour Critical — Countermeasures Installed Fair 1980 16,113
TRIB OF ROYCE BROOK New Jersey Scour Critical — Countermeasures Installed Good 1979 16,104
RED CLAY CREEK Delaware Scour Critical — Countermeasures Installed Fair 1967 16,101
NICHOLAS CREEK South Carolina Scour Critical — Countermeasures Installed Good 1994 16,100
CREEK FRONTAGE RT Oregon Scour Critical — Countermeasures Installed Good 1959 16,064
CREEK FRONTAGE RT Oregon Scour Critical — Countermeasures Installed Good 1959 16,064
EAST FORK MCKAMY BRANCH Texas Scour Critical — Countermeasures Installed Fair 1989 16,047
W BR BRANDYWINE CREEK Pennsylvania Scour Critical — Countermeasures Installed Poor 1914 16,027
B-80A OVER JOHNSON CREEK Oregon Scour Critical — Countermeasures Installed Fair 1971 16,018
Intracoastal Waterway Florida Scour Critical — Countermeasures Installed Fair 1952 16,000
BOOKER CREEK Florida Scour Critical — Countermeasures Installed Fair 1921 16,000
FOUR MILE CANYON CREEK Colorado Scour Critical — Countermeasures Installed Fair 1957 16,000
STILL RIVER Connecticut Scour Critical — Countermeasures Installed Fair 1925 16,000
LAS VEGAS WASH Nevada Scour Critical — Countermeasures Installed Good 1979 16,000
S BR PAW PAW RIVER Michigan Scour Critical — Countermeasures Installed Fair 1960 15,986
S BR PAW PAW RIVER Michigan Scour Critical — Countermeasures Installed Fair 1960 15,986
BRANCH RVR & JOSLIN RD Rhode Island Scour Critical — Countermeasures Installed Poor 1967 15,976
DRY CREEK Washington Scour Critical — Countermeasures Installed Poor 1967 15,974
N BRANCH COOPER RIVER New Jersey Scour Critical — Countermeasures Installed Fair 1935 15,947
WILLIAMS CREEK Indiana Scour Critical — Countermeasures Installed Fair 1930 15,943
GRAND RIVER Michigan Scour Critical — Countermeasures Installed Poor 1915 15,940
FURNACE HILL BROOK Rhode Island Scour Critical — Countermeasures Installed Fair 1957 15,930
WALNUT FORK Indiana Scour Critical — Countermeasures Installed Fair 1964 15,924
WISSAHICKON CREEK Pennsylvania Scour Critical — Countermeasures Installed Poor 1888 15,917
LYNCHES LAKE South Carolina Scour Critical — Countermeasures Installed Fair 1928 15,900
LITTLE BUTTE CREEK Oregon Scour Critical — Countermeasures Installed Fair 1981 15,897
Jackson Creek Oregon Scour Critical — Countermeasures Installed Good 1919 15,894
FLINT RIVER Michigan Scour Critical — Countermeasures Installed Fair 1926 15,881
GREENVILLE BROOK Rhode Island Scour Critical — Countermeasures Installed Fair 1929 15,861
GRANDE DE MANATI RIVER Puerto Rico Scour Critical — Countermeasures Installed Fair 1975 15,800
SHUNGANUNGA CREEK Kansas Scour Critical — Countermeasures Installed Fair 1960 15,800
SHUNGANUNGA CREEK Kansas Scour Critical — Countermeasures Installed Fair 1960 15,800
JOHNS CREEK Washington Scour Critical — Countermeasures Installed Fair 1948 15,751
AQUIA CREEK Virginia Scour Critical — Countermeasures Installed Fair 1957 15,728
MILL CREEK Pennsylvania Scour Critical — Countermeasures Installed Poor 1932 15,720
MILL CANAL Rhode Island Scour Critical — Countermeasures Installed Fair 1918 15,715
WEST BRANCH TROUT BROOK Connecticut Scour Critical — Countermeasures Installed Fair 1901 15,660
SNOHOMISH R & TESTER RD Washington Scour Critical — Countermeasures Installed Fair 1963 15,631
AQUETONG CREEK Pennsylvania Scour Critical — Countermeasures Installed Fair 1939 15,615
HEATH CREEK Texas Scour Critical — Countermeasures Installed Fair 1971 15,612
WAILUKU STRM Hawaii Scour Critical — Countermeasures Installed Fair 1950 15,600
HICKORY CREEK Michigan Scour Critical — Countermeasures Installed Good 1969 15,600
Guanajibo River Puerto Rico Scour Critical — Countermeasures Installed Fair 1998 15,600
DEEP CREEK Oregon Scour Critical — Countermeasures Installed Fair 1957 15,600
FRANK & POET DRAIN Michigan Scour Critical — Countermeasures Installed Fair 1958 15,575
FRANK & POET DRAIN Michigan Scour Critical — Countermeasures Installed Fair 1958 15,575
LONES DITCH Indiana Scour Critical — Countermeasures Installed Fair 1953 15,569
PRICE CREEK Texas Scour Critical — Countermeasures Installed Fair 1972 15,568

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.