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Dam Failure Floods. The Huang He: “China’s Sorrow” . 1887: 2,000,000 dead 1931: 3,700,000 dead 1938: The Chinese dynamite levees to slow the Japanese; 800,000 Chinese died. . Relief of Eastern China. Loess in China. Huang He and Mississippi. Johnstown, Pennsylvania. May 31, 1889
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The Huang He: “China’s Sorrow” • 1887: 2,000,000 dead • 1931: 3,700,000 dead • 1938: The Chinese dynamite levees to slow the Japanese; 800,000 Chinese died.
Johnstown, Pennsylvania May 31, 1889 • Heavy Rain, Dam Failure. 2200 killed March 17, 1936 • Heavy rain + snow melt. 25 fatalities July 19-20, 1977 • 11.8 inches rain, multiple dam failures. 85 killed
St. Francis Dam, California • March 12, 1928, 11:57 PM • Reservoir drained in one hour • Water 140 feet deep • 500 killed • 50 mile flood
St. Francis Dam, California • Built to supply water and power to Los Angeles • Hydraulic lifting • Solution of gypsum in bedrock • Presence of fault and leakage through fault gouge • Reactivation of paleo-landslide
Teton Dam, Idaho • June 5, 1976 • 14 killed • Generally sound engineering practices • Cause of failure • Dam fill inadequately compacted, too dry • Fractured bedrock abutments • Excessive reliance on grout barrier • Piping: erosion of tunnels by leaking water
Teton Dam, Idaho(University of Notre Dame, Department of Engineering and Geological Sciences)
Teton Dam, Idaho(University of Notre Dame, Department of Engineering and Geological Sciences)
Teton Dam, Idaho(University of Notre Dame, Department of Engineering and Geological Sciences)
Teton Dam, Idaho: The Moment of Failure (University of Notre Dame, Department of Engineering and Geological Sciences)
Teton Dam, Idaho(University of Notre Dame, Department of Engineering and Geological Sciences)
Teton Dam, Idaho(University of Notre Dame, Department of Engineering and Geological Sciences)
Teton Dam, Idaho(University of Notre Dame, Department of Engineering and Geological Sciences)
Teton Dam, Idaho(University of Notre Dame, Department of Engineering and Geological Sciences)
Tangiwai Rail Disaster, 1953 • North Island, New Zealand, Dec. 24, 1953 • Crater of Mount Ruapehu collapsed, releasing flood • Mudflow takes out support of rail bridge at Tangiwai • Bridge collapses as train crosses it • 151 killed, 134 survivors
Jokulhlaups Glacial Floods • Subglacial volcanism (Iceland) • Subglacial outbursts • Mont Blanc, July 12, 1898, 200 killed • Ice dam failure • Missoula floods (Pleistocene) • Altai floods (Pleistocene) • Russell Fiord, Alaska, 1986
Predicting Flood Fatalities • Wayne J. Graham, 1999 • A Procedure for Estimating Loss of Life Caused by Dam Failure • DSO-99-06 • U.S. Department of Interior, Bureau of Reclamation, Dam Safety Office
Fatal Dam Failures 1960-1998 • 23 Events • Piping: 6 • Overtopping: 9 • Slope Failure: 2 • Spillway Failure: 2 • Other: 4
Fatality Factors • Flood Severity • Warning Time • Understanding of risk based on events upstream
Flood Severity • High: Area swept clean • Medium: Homes destroyed but trees and wreckage provide refuge, flooding depth greater than 10 feet • Low: Buildings survive, flooding depth less than 10 feet
High Severity • 30-100% fatality rate • 75% used in risk planning • If there is warning, percents apply to people who remain in risk zone
Medium Severity • No warning • Fatality rate 3 – 35% • 15% used in risk planning • 15 – 60 minutes warning • Fatality rate 1 – 8% • 4% used in risk planning • More than 60 minutes warning • Fatality rate 0.5 – 6% • 1% used in risk planning
Low Severity • No warning • Fatality rate 0 – 2% • 1% used in risk planning • 15 – 60 minutes warning • Fatality rate 0 – 1.5% • 0.7% used in risk planning • More than 60 minutes warning • Fatality rate 0 – .06% • .03% used in risk planning