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Finding the payoff in reducing risks. Northwest Hydropower Association February 2013. Bill Christman, PE Engineering Services manager Chelan County PUD Wenatchee, WA. Earthquake . Lack of anti-burst wrapping Lack of connection between upper and lower vertical elements.
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Finding the payoff in reducing risks Northwest Hydropower AssociationFebruary 2013 Bill Christman, PEEngineering Services managerChelan County PUDWenatchee, WA
Earthquake Lack of anti-burst wrapping Lack of connection between upper and lower vertical elements Cyprus Street Viaduct – Loma Prieta earthquake
Hurricane Buildings in known flood zone – mapped before the storm Flooding in New York from Hurricane Sandy
Dam failure Missing head cover bolts(known)41 of 49 bolts recovered had fatigue cracks 10 years of increasingmachine vibration Sayano-Shushenskaya Hydro-electric Dam, Russia - 2009
Stadium collapse Sequencing oversight in demolition – “tiny” wires removed too soon University of Washington - 1987
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Sound practice • 1961 – designed & built to withstand: • 200 mph winds • Magnitude 9.1 earthquake • Center of gravity is 5 feet above ground level Space NeedleSeattle, Wash.
The higher the risk, the higher the cost No ownershipin the results No link to culture and institutional knowledge