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
OVER MILL CREEK Pennsylvania Scour Critical — Countermeasures Installed Poor 1952 7,782
WEST RIVER Rhode Island Scour Critical — Countermeasures Installed Good 1894 7,777
GUNN BRANCH Texas Scour Critical — Countermeasures Installed Fair 1924 7,770
E FK WHITE RIVER OVFL Indiana Scour Critical — Countermeasures Installed Fair 1984 7,762
EAST FORK WHITE RIVER Indiana Scour Critical — Countermeasures Installed Fair 1941 7,762
Ventana Wash Arizona Scour Critical — Countermeasures Installed Fair 1987 7,758
EAST EMMA CREEK Kansas Scour Critical — Countermeasures Installed Good 1971 7,752
EAST EMMA CREEK Kansas Scour Critical — Countermeasures Installed Good 1971 7,752
COPLAY CREEK Pennsylvania Scour Critical — Countermeasures Installed Fair 1921 7,751
LRD CROSS & 2ND ST -MISS Wisconsin Scour Critical — Countermeasures Installed Fair 1940 7,750
GOOSE CREEK Texas Scour Critical — Countermeasures Installed Fair 1972 7,748
ROCKAWAY RIVER New Jersey Scour Critical — Countermeasures Installed Poor 1840 7,737
AU GRES RIVER Michigan Scour Critical — Countermeasures Installed Fair 1930 7,728
DENIOS CREEK Indiana Scour Critical — Countermeasures Installed Fair 1963 7,726
CROWS RUN Pennsylvania Scour Critical — Countermeasures Installed Good 2002 7,719
PONCHATOULA CR. Louisiana Scour Critical — Countermeasures Installed Fair 1932 7,716
THREAD RIVER Michigan Scour Critical — Countermeasures Installed Poor 1928 7,716
S BR PINE RIVER Michigan Scour Critical — Countermeasures Installed Fair 1935 7,706
SAGANING CREEK Michigan Scour Critical — Countermeasures Installed Fair 1937 7,706
BLUE CREEK Indiana Scour Critical — Countermeasures Installed Good 1964 7,703
BROOKER CREEK Florida Scour Critical — Countermeasures Installed Poor 1985 7,700
BEACON HILL BROOK Connecticut Scour Critical — Countermeasures Installed Good 1966 7,700
MUERTO CREEK Puerto Rico Scour Critical — Countermeasures Installed Fair 1940 7,700
HILLSBOROUGH RIVER Florida Scour Critical — Countermeasures Installed Fair 1926 7,700
DIXON CREEK Oregon Scour Critical — Countermeasures Installed Good 1981 7,698
Las Huertas Creek New Mexico Scour Critical — Countermeasures Installed Poor 1975 7,686
DRY CREEK California Scour Critical — Countermeasures Installed Fair 1940 7,681
JOHNSON CREEK Oregon Scour Critical — Countermeasures Installed Fair 1938 7,673
TACONY CREEK Pennsylvania Scour Critical — Countermeasures Installed Fair 1959 7,668
ST. JONES RIVER Delaware Scour Critical — Countermeasures Installed Fair 1934 7,666
PLUM CREEK UPPER BRANCH Pennsylvania Scour Critical — Countermeasures Installed Poor 1982 7,662
Darlenes Brook Darlene New York Scour Critical — Countermeasures Installed Good 1976 7,651
TOUCHET RIVER Washington Scour Critical — Countermeasures Installed Fair 1919 7,642
WILSON CREEK Texas Scour Critical — Countermeasures Installed Fair 2007 7,637
DESCHUTES RIVER Oregon Scour Critical — Countermeasures Installed Fair 1934 7,631
PIKES CREEK Pennsylvania Scour Critical — Countermeasures Installed Poor 1935 7,630
HARVEYS CREEK Pennsylvania Scour Critical — Countermeasures Installed Poor 1935 7,630
BLACK RIVER Washington Scour Critical — Countermeasures Installed Fair 1932 7,629
TEN MILE CREEK TRIBUTARY Texas Scour Critical — Countermeasures Installed Fair 1986 7,623
WEST BEAVER CREEK Tennessee Scour Critical — Countermeasures Installed Fair 1955 7,621
BRANCH Tennessee Scour Critical — Countermeasures Installed Fair 1959 7,620
BRANCH Tennessee Scour Critical — Countermeasures Installed Fair 1959 7,620
SWAN CREEK Alabama Scour Critical — Countermeasures Installed Fair 1926 7,620
OHOP CREEK Washington Scour Critical — Countermeasures Installed Fair 1900 7,615
TRUCKEE RVR Nevada Scour Critical — Countermeasures Installed Poor 1937 7,600
SUTTER BYPASS California Scour Critical — Countermeasures Installed Poor 1938 7,600
CYPRESS STRAND Florida Scour Critical — Countermeasures Installed Fair 1985 7,600
GRAND RIVER Michigan Scour Critical — Countermeasures Installed Fair 1948 7,600
RAVINES BRANCH OF ROUGE Michigan Scour Critical — Countermeasures Installed Fair 1930 7,595
FARR HWY/HONOULIULI STRM Hawaii Scour Critical — Countermeasures Installed Fair 1939 7,587

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.