Tapoco Dam under construction in 1918.  Notice the arched hole at the bottom of the dam.  There was no diversion tunnel built to divert the Little Tennessee River while the dam was erected.  Using earth moving equipment, the river was diverted to the left side of the channel while the right side of the dam was erected, leaving the hole.  Then the river was diverted to the right side of the channel and through the hole while the left side of the dam was built.   After construction was complete, a heavy steel gate was lowered over the hole on the back side of the dam and the lake began to fill.  The water would further press and seal the gate against the dam while the diversion hole was permanently plugged with concrete.    Back