2. Banquiao Dam Failure
Built to withhold rainfall up to a capacity of 12 inches per day, the Banquiao Dam failed its purpose when in 1975 it rained to such an extent that the dam was unable to hold itself. The dam under undue water pressure burst out sending water waves as high as 7 meters and 6 miles wide. Communication failure and inadequate preparation resulted in the loss of an estimated 230,000 lives.