Morrell became a member of the South Fork Fishing and Hunting Club , site of the South Fork Dam , which formed Lake Conemaugh , in order to keep a watchful eye on the dam under its stewardship , and campaigned to club officials , especially to its founder , Benjamin Franklin Ruff , regarding the safety of the dam . The failure of that dam eventually caused the great Johnstown Flood of May 31 , 1889 , which killed more than 2,200 people , and was then the largest disaster in U.S. history . Morrell insisted on inspections of the dam 's breastwork both by his own engineers and those of the Pennsylvania Railroad . Morrell 's warnings went unheeded , and his offer to effect repairs , partially at his own expense , was rejected by club president , Benjamin F. Ruff ( who died two years prior to the flood ) . Morrell died four years before the Johnstown Flood ; his membership was then bought by his colleague , Cyrus Elder , who was legal counsel for the Cambria Iron and Steel Company
Johnstown Flood
Johnstown Flood
Daniel Johnson Morrell