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
DUTCH GAP CANAL Illinois Scour Critical — Countermeasures Ineffective Fair 1960 4,850
RED WASH New Mexico Scour Critical — Countermeasures Ineffective Fair 1960 4,813
WHEELER CREEK Texas Scour Critical — Countermeasures Ineffective Good 2000 4,812
SAN PEDRO CREEK Texas Scour Critical — Countermeasures Ineffective Good 2022 4,810
BEAR CREEK Texas Scour Critical — Countermeasures Ineffective Fair 1962 4,803
ISLAND CREEK West Virginia Scour Critical — Countermeasures Ineffective Good 2005 4,800
WOOD CREEK Texas Scour Critical — Countermeasures Ineffective Good 1942 4,757
TRIB W FORK TRINITY RIV Texas Scour Critical — Countermeasures Ineffective Fair 1940 4,748
Leona River Texas Scour Critical — Countermeasures Ineffective Fair 1995 4,727
DRAW Texas Scour Critical — Countermeasures Ineffective Good 2010 4,726
DRAW Texas Scour Critical — Countermeasures Ineffective Good 2010 4,726
RED GULLY Texas Scour Critical — Countermeasures Ineffective Good 2008 4,724
ROCK CREEK RELIEF #2 Texas Scour Critical — Countermeasures Ineffective Good 2001 4,720
ROCK CREEK Texas Scour Critical — Countermeasures Ineffective Good 2002 4,720
ROCK CREEK RELIEF #3 Texas Scour Critical — Countermeasures Ineffective Good 2001 4,720
W FK SAN JACINTO S REL Texas Scour Critical — Countermeasures Ineffective Fair 1997 4,707
W FK SAN JACINTO RIVER Texas Scour Critical — Countermeasures Ineffective Good 1997 4,707
W FK SAN JAC RI N REL Texas Scour Critical — Countermeasures Ineffective Good 1997 4,707
MINNEHAHA CREEK Minnesota Scour Critical — Countermeasures Ineffective Good 2021 4,700
WATER UNKNOWN CREEK Massachusetts Scour Critical — Countermeasures Ineffective Fair 1992 4,696
DRAIN Texas Scour Critical — Countermeasures Ineffective Good 1991 4,689
YELLOW STEER SLOUGH Texas Scour Critical — Countermeasures Ineffective Good 2002 4,680
LITTLE SLOUGH Texas Scour Critical — Countermeasures Ineffective Fair 2002 4,680
CLEAR CREEK Texas Scour Critical — Countermeasures Ineffective Good 1954 4,676
TRIB OF FURNEAUX CR Texas Scour Critical — Countermeasures Ineffective Fair 1983 4,670
BRAZOS RIVER RELIEF Texas Scour Critical — Countermeasures Ineffective Good 2023 4,658
JONES CREEK Texas Scour Critical — Countermeasures Ineffective Good 2024 4,658
BUFFALO BAYOU Texas Scour Critical — Countermeasures Ineffective Fair 1977 4,653
GARRETT CREEK RELIEF Texas Scour Critical — Countermeasures Ineffective Fair 1948 4,650
GARRETT CREEK Texas Scour Critical — Countermeasures Ineffective Fair 1948 4,650
LITTLE CEDAR BAYOU Texas Scour Critical — Countermeasures Ineffective Good 2009 4,629
CARRIZO CREEK Texas Scour Critical — Countermeasures Ineffective Good 2024 4,625
CHOCTAW CRK RELIEF Texas Scour Critical — Countermeasures Ineffective Fair 1934 4,620
CAYADUTTA CREEK New York Scour Critical — Countermeasures Ineffective Good 2024 4,616
DRAW Texas Scour Critical — Countermeasures Ineffective Fair 1929 4,601
LAKE CREEK SLOUGH Texas Scour Critical — Countermeasures Ineffective Fair 1929 4,601
FARBER BR Texas Scour Critical — Countermeasures Ineffective Fair 1960 4,600
COPELAND DITCH Texas Scour Critical — Countermeasures Ineffective Good 2003 4,589
IRON ORE CRK RELIEF Texas Scour Critical — Countermeasures Ineffective Good 1934 4,585
N MAIN DRAINAGE DITCH Texas Scour Critical — Countermeasures Ineffective Good 1987 4,581
COPPER BRANCH CREEK Texas Scour Critical — Countermeasures Ineffective Good 1928 4,571
VINCE BAYOU Texas Scour Critical — Countermeasures Ineffective Good 1998 4,560
WALNUT CREEK Texas Scour Critical — Countermeasures Ineffective Fair 1960 4,557
FARBER BRANCH Texas Scour Critical — Countermeasures Ineffective Fair 1986 4,550
WALLER CREEK Texas Scour Critical — Countermeasures Ineffective Fair 1936 4,546
GIBBONS CREEK Texas Scour Critical — Countermeasures Ineffective Fair 1936 4,546
LITTLE WICHITA RIVER REL Texas Scour Critical — Countermeasures Ineffective Fair 1928 4,542
SEVEN MILE CREEK Texas Scour Critical — Countermeasures Ineffective Good 1954 4,537
NINE MILE CREEK Texas Scour Critical — Countermeasures Ineffective Fair 1952 4,537
GIBSON CREEK Texas Scour Critical — Countermeasures Ineffective Good 1954 4,537

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.