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
NEW HOPE CREEK North Carolina Scour Critical — Countermeasures Installed Fair 1979 14,500
BRUSHY CREEK South Carolina Scour Critical — Countermeasures Installed Fair 1969 14,500
ICWW at Navarre Florida Scour Critical — Countermeasures Installed Fair 1960 14,500
STONEY CREEK North Carolina Scour Critical — Countermeasures Installed Fair 1977 14,500
STONEY CREEK North Carolina Scour Critical — Countermeasures Installed Fair 1960 14,500
LITTLE NORTHEAST North Carolina Scour Critical — Countermeasures Installed Fair 1994 14,500
PARK CREEK Pennsylvania Scour Critical — Countermeasures Installed Fair 1985 14,495
ULATIS CREEK California Scour Critical — Countermeasures Installed Fair 1970 14,480
Necanicum River Oregon Scour Critical — Countermeasures Installed Fair 1930 14,464
DAMARISCOTTA RIVER Maine Scour Critical — Countermeasures Installed Fair 1952 14,450
ZACHARIAS CREEK Pennsylvania Scour Critical — Countermeasures Installed Fair 1970 14,446
PENNA CANAL Pennsylvania Scour Critical — Countermeasures Installed Fair 1934 14,443
ST JOSEPH RIVER Indiana Scour Critical — Countermeasures Installed Fair 1927 14,437
WAIOLANI STRM Hawaii Scour Critical — Countermeasures Installed Good 1934 14,427
PUDDING RIVER Oregon Scour Critical — Countermeasures Installed Fair 1979 14,416
PUDDING RIVER OVERFLOW Oregon Scour Critical — Countermeasures Installed Fair 1985 14,416
BRANCH MARTINS CREEK Pennsylvania Scour Critical — Countermeasures Installed Fair 1954 14,412
ISINGLASS RIVER New Hampshire Scour Critical — Countermeasures Installed Poor 1951 14,407
THREAD RIVER Michigan Scour Critical — Countermeasures Installed Fair 1995 14,407
DORCHESTER WATERWAY Florida Scour Critical — Countermeasures Installed Good 1992 14,400
LA PLATA RIVER Puerto Rico Scour Critical — Countermeasures Installed Poor 1979 14,400
DICKISON RUN CREEK Illinois Scour Critical — Countermeasures Installed Poor 1958 14,400
WATER ASSABET RIVER Massachusetts Scour Critical — Countermeasures Installed Fair 1886 14,400
STRAWBERRY CREEK Florida Scour Critical — Countermeasures Installed Fair 1969 14,400
BRANCH NESHAMINY CREEK Pennsylvania Scour Critical — Countermeasures Installed Fair 1932 14,399
FRY DITCH CREEK #2 Oklahoma Scour Critical — Countermeasures Installed Poor 1950 14,386
WEBB DRAIN Michigan Scour Critical — Countermeasures Installed Good 1961 14,378
WEBB DRAIN Michigan Scour Critical — Countermeasures Installed Fair 1961 14,378
SPROGELS RUN Pennsylvania Scour Critical — Countermeasures Installed Poor 1910 14,340
BRANCH Tennessee Scour Critical — Countermeasures Installed Fair 1930 14,335
LITTLE BLACK CREEK Indiana Scour Critical — Countermeasures Installed Fair 1963 14,329
LITTLE BLACK CREEK Indiana Scour Critical — Countermeasures Installed Good 1963 14,329
POND FLAT DITCH Indiana Scour Critical — Countermeasures Installed Poor 1946 14,325
POND FLAT DITCH Indiana Scour Critical — Countermeasures Installed Poor 1946 14,325
BLACK RIVER Michigan Scour Critical — Countermeasures Installed Fair 1955 14,315
BLACK RIVER Michigan Scour Critical — Countermeasures Installed Fair 1930 14,315
BLUE RIVER Kansas Scour Critical — Countermeasures Installed Good 1966 14,313
BRANCH OF SALEM CREEK New Jersey Scour Critical — Countermeasures Installed Fair 1919 14,306
NEWMAN SWAMP South Carolina Scour Critical — Countermeasures Installed Fair 1973 14,300
NEWMAN SWAMP South Carolina Scour Critical — Countermeasures Installed Fair 1973 14,300
PASS MANCHAC Louisiana Scour Critical — Countermeasures Installed Fair 1977 14,300
CAGUITAS RIVER Puerto Rico Scour Critical — Countermeasures Installed Fair 1999 14,300
DEER CREEK Oregon Scour Critical — Countermeasures Installed Fair 1937 14,285
SKIPPACK CREEK Pennsylvania Scour Critical — Countermeasures Installed Fair 1792 14,242
RIPPOWAM RIVER Connecticut Scour Critical — Countermeasures Installed Poor 1954 14,220
CHIPPEWA RIVER Michigan Scour Critical — Countermeasures Installed Fair 1940 14,220
Schooner Creek Oregon Scour Critical — Countermeasures Installed Fair 1945 14,212
GUATEMALA RIVER Puerto Rico Scour Critical — Countermeasures Installed Fair 1917 14,200
NORTH ARCHIE CREEK Florida Scour Critical — Countermeasures Installed Good 1997 14,200
ST. JOSEPH SOUND Florida Scour Critical — Countermeasures Installed Fair 1963 14,200

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.