'Wash Out! in July 1870, a large party assembled at the other end of this tunnel to watch the Yarra take its new course. It must have been a spectacular sight!
Overall, the project cost the Evelyn Tunnel Gold Mining Company [pound]2,100 ($4,200) to construct. The dam (later washed away) consisted of piles supported with back stakes driven in at an angle of 45 [degrees], and 11,000 sand bags for added strength. After twelve months the company was liquidated as the expenses were too high and returns poor.'
Submitted by: @IanThorp