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
BEANBLOSSOM OVERFLOW Indiana Scour Critical — Countermeasures Installed Good 1972 15,560
BRANCH OF CLARKS CREEK Indiana Scour Critical — Countermeasures Installed Fair 1940 15,550
BRANCH OF CLARKS CREEK Indiana Scour Critical — Countermeasures Installed Fair 1940 15,550
HO-HO-KUS BROOK New Jersey Scour Critical — Countermeasures Installed Fair 1957 15,522
BEANBLOSSOM OVERFLOW Indiana Scour Critical — Countermeasures Installed Fair 1946 15,510
Caney Crk Texas Scour Critical — Countermeasures Installed Good 2022 15,500
FANCY BLUFF CREEK Georgia Scour Critical — Countermeasures Installed Good 1997 15,500
POCASSET RIVER Rhode Island Scour Critical — Countermeasures Installed Good 2019 15,500
MEADE ST. DRAINAGE South Dakota Scour Critical — Countermeasures Installed Good 1964 15,500
FIVE MILE CREEK Texas Scour Critical — Countermeasures Installed Fair 1957 15,462
TOBY CREEK Pennsylvania Scour Critical — Countermeasures Installed Fair 1941 15,449
TOBY CREEK Pennsylvania Scour Critical — Countermeasures Installed Poor 1941 15,449
PEQUANNOCK RIVER New Jersey Scour Critical — Countermeasures Installed Fair 1969 15,440
HASKELL SLOUGH Washington Scour Critical — Countermeasures Installed Fair 1957 15,411
BRUSH HEAP CREEK Indiana Scour Critical — Countermeasures Installed Fair 1974 15,403
Pudding River Oregon Scour Critical — Countermeasures Installed Fair 1922 15,402
INTRACOASTAL WATERWAY Florida Scour Critical — Countermeasures Installed Fair 1981 15,400
BIG FOSSIL CREEK Texas Scour Critical — Countermeasures Installed Fair 1990 15,396
LITTLE RICHLAND CREEK Tennessee Scour Critical — Countermeasures Installed Fair 1960 15,352
LITTLE RICHLAND CREEK Tennessee Scour Critical — Countermeasures Installed Fair 1960 15,352
CLINTON RIVER Michigan Scour Critical — Countermeasures Installed Fair 1959 15,351
Tamiami Canal C-4 Florida Scour Critical — Countermeasures Installed Good 1965 15,350
FLINT RIVER Michigan Scour Critical — Countermeasures Installed Fair 1967 15,328
WEST FK WHITE LICK CREEK Indiana Scour Critical — Countermeasures Installed Fair 1940 15,322
CARTERSBURG BRANCH Indiana Scour Critical — Countermeasures Installed Fair 1940 15,322
CROSS BAYOU Louisiana Scour Critical — Countermeasures Installed Good 1983 15,302
BATTLE CREEK RIVER Michigan Scour Critical — Countermeasures Installed Fair 1966 15,300
RABBIT RIVER Michigan Scour Critical — Countermeasures Installed Fair 1957 15,300
B-136 X COLUMBIA SLOUGH Oregon Scour Critical — Countermeasures Installed Fair 1992 15,271
South Yamhill River Oregon Scour Critical — Countermeasures Installed Fair 1963 15,252
SYCAMORE RUN Pennsylvania Scour Critical — Countermeasures Installed Fair 1926 15,217
BOIS DE SIOUX RIVER North Dakota Scour Critical — Countermeasures Installed Fair 1929 15,200
CANNON RIVER Minnesota Scour Critical — Countermeasures Installed Fair 1954 15,200
JENKINS BRANCH Texas Scour Critical — Countermeasures Installed Fair 1983 15,176
WOONASQUATUCKET RIVER Rhode Island Scour Critical — Countermeasures Installed Fair 1994 15,175
Bowers Slough Oregon Scour Critical — Countermeasures Installed Fair 1964 15,140
MT DESERT NARROWS Maine Scour Critical — Countermeasures Installed Fair 1958 15,122
SLOUGH & CNTY RD Washington Scour Critical — Countermeasures Installed Fair 1947 15,105
BRANCH RIVER Rhode Island Scour Critical — Countermeasures Installed Poor 1919 15,100
DUCK CREEK Texas Scour Critical — Countermeasures Installed Good 1972 15,097
EDWARDS RUN New Jersey Scour Critical — Countermeasures Installed Fair 1920 15,089
CAPE ISLAND CREEK New Jersey Scour Critical — Countermeasures Installed Poor 1927 15,085
RAILROAD DRAIN Michigan Scour Critical — Countermeasures Installed Fair 1950 15,061
CREVE COEUR CR Missouri Scour Critical — Countermeasures Installed Fair 1968 15,056
STEVENS CREEK California Scour Critical — Countermeasures Installed Fair 1922 15,041
LITTLE BLACK CREEK Pennsylvania Scour Critical — Countermeasures Installed Fair 1928 15,032
JENKINS CREEK Washington Scour Critical — Countermeasures Installed Fair 1929 15,015
BOULDER CREEK Colorado Scour Critical — Countermeasures Installed Poor 1938 15,000
WATER EAST RIVER Massachusetts Scour Critical — Countermeasures Installed Fair 1914 15,000
SNAKE RIVER;HEYBURN BR. Idaho Scour Critical — Countermeasures Installed Fair 1955 15,000

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.