The Iraqis built a dam on a drywall (gypsum) foundation. Has to be one of the biggest engineering blunders in history.
#39 Mulholland would agree with you. Mulholland said the day it collapsed that all dams leak.
St. Francis Dam
https://en.wikipedia.org/wiki/St._Francis_Dam
Many photos.
http://tinyurl.com/zqdl8vo