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
NORTH ARCHIE CREEK Florida Scour Critical — Countermeasures Installed Good 1997 14,200
GUATEMALA RIVER Puerto Rico Scour Critical — Countermeasures Installed Fair 1940 14,200
LICK CREEK Indiana Scour Critical — Countermeasures Installed Fair 1963 14,181
MORGAN CREEK Texas Scour Critical — Countermeasures Installed Fair 1963 14,162
GARDNERS CREEK Pennsylvania Scour Critical — Countermeasures Installed Fair 1963 14,152
North Fork Ash Creek Oregon Scour Critical — Countermeasures Installed Poor 1954 14,149
BARREN CREEK Indiana Scour Critical — Countermeasures Installed Good 1963 14,139
BARREN CREEK Indiana Scour Critical — Countermeasures Installed Good 1963 14,139
CROYS CREEK Indiana Scour Critical — Countermeasures Installed Fair 1966 14,131
OVER BENNYS RUN Pennsylvania Scour Critical — Countermeasures Installed Fair 1947 14,116
HWY 1 SB CONN 7 OFF RAMP Oregon Scour Critical — Countermeasures Installed Fair 1963 14,116
ABITA RIVER Louisiana Scour Critical — Countermeasures Installed Fair 1972 14,110
CHINCHUBA BRANCH Louisiana Scour Critical — Countermeasures Installed Fair 1972 14,110
CHANNEL Puerto Rico Scour Critical — Countermeasures Installed Fair 1963 14,100
DEEP FORK CREEK Oklahoma Scour Critical — Countermeasures Installed Poor 1940 14,100
JOHNSON CREEK Oregon Scour Critical — Countermeasures Installed Fair 1935 14,100
SINGLETON DITCH Indiana Scour Critical — Countermeasures Installed Fair 1964 14,069
DOE CREEK Indiana Scour Critical — Countermeasures Installed Fair 1926 14,069
Beaver Creek Oregon Scour Critical — Countermeasures Installed Fair 1953 14,067
SAN DIEGUITO RIVER California Scour Critical — Countermeasures Installed Poor 1932 14,027
INDIAN CREEK/ 3030F04 Pennsylvania Scour Critical — Countermeasures Installed Fair 1930 14,013
CROSS BAYOU Louisiana Scour Critical — Countermeasures Installed Poor 1960 14,003
MISSISSINEWA RIVER Indiana Scour Critical — Countermeasures Installed Fair 1910 14,000
SAN ANSELMO CREEK California Scour Critical — Countermeasures Installed Fair 1940 14,000
OLDFIELD CREEK Florida Scour Critical — Countermeasures Installed Fair 1957 14,000
GUADIANA RIVER Puerto Rico Scour Critical — Countermeasures Installed Fair 1998 14,000
Little Beaver Creek Oregon Scour Critical — Countermeasures Installed Fair 1953 13,994
STONY BROOK New Jersey Scour Critical — Countermeasures Installed Fair 1958 13,979
STONY BROOK New Jersey Scour Critical — Countermeasures Installed Fair 1908 13,979
VIRGIN RIVER Utah Scour Critical — Countermeasures Installed Fair 1976 13,973
WOLF CREEK Oklahoma Scour Critical — Countermeasures Installed Poor 1977 13,970
WHITE RIVER Indiana Scour Critical — Countermeasures Installed Fair 1937 13,970
TRUCKEE RVR Nevada Scour Critical — Countermeasures Installed Fair 1961 13,950
TRUCKEE RVR Nevada Scour Critical — Countermeasures Installed Fair 1961 13,950
WATER BEAVER BROOK Massachusetts Scour Critical — Countermeasures Installed Fair 1921 13,913
NORTH BR.NESHAMINY CREEK Pennsylvania Scour Critical — Countermeasures Installed Poor 1948 13,911
PEAVINE CREEK Georgia Scour Critical — Countermeasures Installed Fair 1969 13,900
JOES CREEK Florida Scour Critical — Countermeasures Installed Fair 1981 13,900
RED CEDAR RIVER Michigan Scour Critical — Countermeasures Installed Poor 1924 13,900
CAMPBELL CR MINN DR S.B. Alaska Scour Critical — Countermeasures Installed Fair 1985 13,900
CAMPBELL CR MINN DR N.B. Alaska Scour Critical — Countermeasures Installed Good 1985 13,900
HOHOKUS BROOK New Jersey Scour Critical — Countermeasures Installed Fair 1904 13,889
INTRACOASTAL WATERWAY Florida Scour Critical — Countermeasures Installed Good 1939 13,888
NUUANU STRM Hawaii Scour Critical — Countermeasures Installed Fair 1934 13,883
SHELTON DITCH Oregon Scour Critical — Countermeasures Installed Fair 1988 13,876
WHITE ROCK CREEK Texas Scour Critical — Countermeasures Installed Fair 1989 13,860
WHITE ROCK CREEK Texas Scour Critical — Countermeasures Installed Fair 1974 13,860
E.FORK GOOSE CRK Texas Scour Critical — Countermeasures Installed Good 1994 13,859
COBBS CREEK Pennsylvania Scour Critical — Countermeasures Installed Fair 1927 13,856
WALLKILL RIVER TRIBUTARY New Jersey Scour Critical — Countermeasures Installed Fair 1919 13,846

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.