A History of Dam Failures
Bruce A. DeVantier
Department of Civil & Environmental EngineeringSouthern Illinois University Carbondale
Presentation to Egyptian Chapter ISPEApril 24, 2017
Recent Focus
• Oroville Dam 3/17LA Times photo
• Spillway begin to break apart at 55,000 cfsDesign capacity was 300,000
• Nearly 200,000 evacuated – no direct deaths• Main design flaw was too thin concrete spillway
floor – also too little anchoring• Emergency spillway was ineffective with erosion
soon after its implementation – maintenance schedules slipped with many low flow years
US Agencies Concerned with Dam Safety
• FEMA and various state emergency management organizations
• US Army Corps of Engineersincludes dams and levees
• Association of Dam Safety Officials
• ASCE – March 2013 Infrastructure Report Card Nation’s dams given overall D grade with no state receiving A or F grade
Johnstown Flood 1889
• Over 2,000 deaths in western Pennsylvania• South Fork Hunting and Fishing Club
reclaimed an abandoned earthen dam impoundment for members – including magnates Carnagie, Frick and Mellon
• After continued heavy rains, the dam failed on the morning of May 31 (now National Dam Safety Awareness Day)
• Only effective outlet (emergency spillway) had been screened to hold in fish
• Dam failed catastrophically
Saint Francis 1928
St. Francis Dam was built in San
Francisquito Canyon about 7
miles upstream of its mouth
between 1924-26 by the City of Los Angeles Bureau of Waterworks and Supply• Official death toll: 432 people• Dam unknowingly built on landslides due to
fault line near dam is primary cause• Only operated two years
Vajont Italy 1963
•
• Landslide into impoundment caused giant wave of water without dam failure
• 1917 deaths• Actually considered as a manmade mega-
tsunami
Teton Dam 1976
•
Leaks of earthen Bureau of Reclamation Damcaused catastrophic failure
• 14 killed, more than 200 families homeless• Seepage through dam well below water
level eventually lead to whirlpool which
swallowed 2 of 4 bulldozers filling it
Teton Dam continued
•
• Water pore pressure during seepage can lead to actual separation of grains and actually lead to fluidization
Lawn Lake (near Estes Park) 1982
• Built in 1903 as a 3xexpansion of natural lake
• Lax inspection (remote)• Piping leaks lead to
erosion and eventual earthen dam failure
• 3 people killed• $30 million un-
compensated loss
Lawn Lake Photo
Hurricane Katrina levee failures 2005
• Six major levee breaks – numerous smaller• Storm surge overtopping weakened levees
More Katrina breaks
• Quality of levee materials & placement cited as deficient • Over 100,000 homes flood, no direct death estimates
Ka Loko Dam Failure, Kauai 2006
• Reservoir created by earthen dam on north side of island 1890
• Complicated ownership• Irrigation ditch responsibility
disconnected from reservoir
• Primary causes were filling of spillway by new owner and lack of maintenance of reservoir and irrication ditch
Kaloko Dam Failure Results
• 7 people killed including pregnant woman• Uneven dam crest also a contributing factor
The Great Flood (Younger Dryas Impact Hypothesis J. Geology, 2014)
• At greatest glacial extent (12,000 – 14,000 years ago) there was a mass extinction by geological records
• Hypothesis is that large objects in a comet tail struck earth with great energy to create mass flooding
The Great Flood (Younger Dryas Impact Hypothesis)
• Many cultures in the proposed impact field have flood stories
• Anthropological digs show evidence ofhuman survivor centers of knowledge
• A return of comet remnants several thousand years later also hypothosized
Northwest US Geologic Evidence
• For same geological period (12,000 – 14,000 years ago) geologist Randall Carlson sees mud and water wallas the impetus for dramatic erosion