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
MATZ AVE RR DRAIN. DITCH Texas Scour Critical — Countermeasures Ineffective Fair 1971 9,450
SPRING GULLY Texas Scour Critical — Countermeasures Ineffective Fair 1930 9,445
DRAW Texas Scour Critical — Countermeasures Ineffective Fair 1922 9,442
HCFCD DITCH Texas Scour Critical — Countermeasures Ineffective Fair 1960 9,430
DRAW Texas Scour Critical — Countermeasures Ineffective Good 1941 9,384
DRAINAGE DITCH Texas Scour Critical — Countermeasures Ineffective Fair 2010 9,382
ROCK CREEK Texas Scour Critical — Countermeasures Ineffective Good 2000 9,366
WHITE OAK BAYOU Texas Scour Critical — Countermeasures Ineffective Fair 1987 9,360
WHITE OAK BAYOU Texas Scour Critical — Countermeasures Ineffective Fair 1987 9,360
DONNA DRAIN Texas Scour Critical — Countermeasures Ineffective Good 1988 9,359
LITTLE LIVE OAK CREEK Texas Scour Critical — Countermeasures Ineffective Fair 1922 9,337
JACKSON BRANCH Texas Scour Critical — Countermeasures Ineffective Fair 1952 9,317
DRAW Texas Scour Critical — Countermeasures Ineffective Good 1939 9,307
SEABOURNE CREEK Texas Scour Critical — Countermeasures Ineffective Fair 1931 9,296
OLD SIMS BAYOU Texas Scour Critical — Countermeasures Ineffective Fair 1945 9,270
DRAW Texas Scour Critical — Countermeasures Ineffective Fair 2002 9,239
E FORK CRYSTAL CREEK Texas Scour Critical — Countermeasures Ineffective Good 1941 9,237
CLEAR CREEK Texas Scour Critical — Countermeasures Ineffective Fair 1971 9,170
LACY CREEK Texas Scour Critical — Countermeasures Ineffective Fair 1938 9,132
LACY CREEK RELIEF Texas Scour Critical — Countermeasures Ineffective Fair 1938 9,132
BIG SANDY CREEK BRANCH Texas Scour Critical — Countermeasures Ineffective Fair 1934 9,071
Swan Creek (Relief) Alabama Scour Critical — Countermeasures Ineffective Good 2023 9,052
Swan Creek (MC) Alabama Scour Critical — Countermeasures Ineffective Good 2023 9,052
LAKE WOODLANDS Texas Scour Critical — Countermeasures Ineffective Good 2000 9,026
STEWARTS CREEK Texas Scour Critical — Countermeasures Ineffective Good 2011 9,010
CANEY CREEK Texas Scour Critical — Countermeasures Ineffective Good 2011 9,010
MAYDE CREEK Texas Scour Critical — Countermeasures Ineffective Good 2014 9,000
WATER PAWTUCKET CANAL Massachusetts Scour Critical — Countermeasures Ineffective Good 1852 9,000
CLAY RD & MAYDE CRK Texas Scour Critical — Countermeasures Ineffective Good 2014 9,000
MAYDE CREEK Texas Scour Critical — Countermeasures Ineffective Good 2014 9,000
CLAY RD & MAYDE CRK Texas Scour Critical — Countermeasures Ineffective Good 2014 9,000
DELAWARE CREEK Texas Scour Critical — Countermeasures Ineffective Good 1934 9,000
FRENCH CREEK Ohio Scour Critical — Countermeasures Ineffective Good 2023 8,955
VOGEL CREEK Texas Scour Critical — Countermeasures Ineffective Fair 1998 8,950
GUADALUPE RIVER Texas Scour Critical — Countermeasures Ineffective Good 2005 8,950
VOGEL CREEK Texas Scour Critical — Countermeasures Ineffective Good 1998 8,950
FILBIN CREEK South Carolina Scour Critical — Countermeasures Ineffective Fair 1992 8,900
LITTLE VINCE BAYOU Texas Scour Critical — Countermeasures Ineffective Fair 1981 8,850
PILLOT GULLY Texas Scour Critical — Countermeasures Ineffective Good 2004 8,840
ROCK CREEK Texas Scour Critical — Countermeasures Ineffective Fair 1934 8,815
SABINAL RIVER Texas Scour Critical — Countermeasures Ineffective Good 1932 8,800
DRAW Texas Scour Critical — Countermeasures Ineffective Fair 1934 8,791
HCFCD DITCH K140-04-00 Texas Scour Critical — Countermeasures Ineffective Good 2004 8,780
OJO DE AGUA CRK Texas Scour Critical — Countermeasures Ineffective Fair 1969 8,778
OJO DE AGUA CRK Texas Scour Critical — Countermeasures Ineffective Good 1981 8,778
CANEY CREEK Texas Scour Critical — Countermeasures Ineffective Good 1993 8,732
W BRANCH LIVE OAK CREEK Texas Scour Critical — Countermeasures Ineffective Fair 1951 8,716
PARKER CREEK BRANCH Texas Scour Critical — Countermeasures Ineffective Fair 1951 8,716
SPRING CREEK Texas Scour Critical — Countermeasures Ineffective Good 1986 8,694
RANGE CREEK Texas Scour Critical — Countermeasures Ineffective Good 1986 8,694

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.