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
BEAVERHEAD RIVER Montana Scour Critical — Countermeasures Installed Fair 1949 2,865
COCKEREL CREEK Louisiana Scour Critical — Countermeasures Installed Fair 1967 2,862
CREEK Louisiana Scour Critical — Countermeasures Installed Poor 1967 2,862
CREEK Louisiana Scour Critical — Countermeasures Installed Fair 1970 2,862
PIGEON RIVER Tennessee Scour Critical — Countermeasures Installed Good 1967 2,861
DEAD CREEK Michigan Scour Critical — Countermeasures Installed Fair 1981 2,860
DUNCAN CREEK Wisconsin Scour Critical — Countermeasures Installed Poor 1934 2,855
POWDER R (HUGHES LN) Oregon Scour Critical — Countermeasures Installed Good 1966 2,854
NATALBANY RIVER Louisiana Scour Critical — Countermeasures Installed Fair 1957 2,854
WILSON STREAM Maine Scour Critical — Countermeasures Installed Poor 1958 2,854
WEBER RIVER Utah Scour Critical — Countermeasures Installed Fair 1936 2,848
DUCK RIVER Tennessee Scour Critical — Countermeasures Installed Fair 1951 2,848
FIVE MILE CREEK Texas Scour Critical — Countermeasures Installed Fair 1961 2,843
COLE CREEK Texas Scour Critical — Countermeasures Installed Fair 1975 2,842
SMACKOVER RELIEF Arkansas Scour Critical — Countermeasures Installed Fair 1974 2,840
LEAF RIVER RELIEF Mississippi Scour Critical — Countermeasures Installed Fair 1967 2,840
NASELLE R Washington Scour Critical — Countermeasures Installed Good 1953 2,839
LITT BEAVER KILL New York Scour Critical — Countermeasures Installed Fair 1935 2,839
CUB CREEK Tennessee Scour Critical — Countermeasures Installed Fair 1925 2,836
ROBERTSON CREEK Tennessee Scour Critical — Countermeasures Installed Fair 1925 2,836
CYPRESS CREEK Tennessee Scour Critical — Countermeasures Installed Fair 1925 2,836
BEECH CR(MT VERNON) Oregon Scour Critical — Countermeasures Installed Fair 1956 2,836
EVANS BRANCH ROUGE RIVER Michigan Scour Critical — Countermeasures Installed Fair 1970 2,834
HAMMONASSET RIVER Connecticut Scour Critical — Countermeasures Installed Fair 1935 2,833
BEAVER DAM RUN Pennsylvania Scour Critical — Countermeasures Installed Fair 1953 2,830
TUPPER BROOK Michigan Scour Critical — Countermeasures Installed Fair 1980 2,830
LIMESTONE CREEK New York Scour Critical — Countermeasures Installed Fair 1923 2,829
CREEK Louisiana Scour Critical — Countermeasures Installed Fair 1958 2,828
NORTH CHENIERE CR Louisiana Scour Critical — Countermeasures Installed Poor 1958 2,828
CREEK Louisiana Scour Critical — Countermeasures Installed Fair 1958 2,828
MAD RIVER New Hampshire Scour Critical — Countermeasures Installed Poor 1979 2,828
KIOWA BRANCH Texas Scour Critical — Countermeasures Installed Fair 1951 2,827
BRANCH Tennessee Scour Critical — Countermeasures Installed Fair 1962 2,822
BEAVER CREEK Tennessee Scour Critical — Countermeasures Installed Fair 1962 2,822
GASCONADE RVR Missouri Scour Critical — Countermeasures Installed Fair 1964 2,822
SANDY CREEK Pennsylvania Scour Critical — Countermeasures Installed Fair 1950 2,818
LABORDE BRANCH SANDY CR Pennsylvania Scour Critical — Countermeasures Installed Fair 1950 2,818
BITTERROOT RIVER Montana Scour Critical — Countermeasures Installed Fair 1974 2,814
INDIAN CABIN CREEK New Jersey Scour Critical — Countermeasures Installed Poor 1919 2,813
DUKES BROOK New Jersey Scour Critical — Countermeasures Installed Fair 1925 2,810
SOUTH YAMHILL RIVER Oregon Scour Critical — Countermeasures Installed Fair 1970 2,809
E FORK TRINITY RIVER Texas Scour Critical — Countermeasures Installed Fair 1982 2,805
SIX MILE CREEK Indiana Scour Critical — Countermeasures Installed Fair 1934 2,803
BRANCH BRANDYWINE CREEK Pennsylvania Scour Critical — Countermeasures Installed Poor 1935 2,802
TRIB LITTLE SWATARA CK Pennsylvania Scour Critical — Countermeasures Installed Fair 1934 2,801
CATHERINE CR (DAVIS DAM) Oregon Scour Critical — Countermeasures Installed Fair 1966 2,801
SNAKE RIVER Idaho Scour Critical — Countermeasures Installed Fair 1967 2,800
MIDDLE BRANCH BUSHY CK South Carolina Scour Critical — Countermeasures Installed Fair 1982 2,800
SALKEHATCHIE RIVER SWAMP South Carolina Scour Critical — Countermeasures Installed Fair 2002 2,800
GUAMANI RIVER Puerto Rico Scour Critical — Countermeasures Installed Fair 1925 2,800

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.