The lake was created primarily for irrigation to expand agriculture across the tableland's fertile volcanic soils. It is huge, covering 8600 acres and gathers water from a 545 square kilometer catchment. It also provides hydro-electricity and water for the surrounding towns.
The area was highly volcanic in the past which is why the surrounding farmland has such rich soil. The volcanic cones, known as the Seven Sisters, were formed when explosive eruptions poured scoria and ash out of vents to create conical mounds of lightweight volcanic rock. The nearby crater lakes Barrine and Eacham are the result of rising lava meeting the water table and the super-heated steam exploding so violently that a crater is formed.
With such a large body of water and 200km of shoreline it is hugely popular for camping, fishing and water-sports. Tinaroo and the tablelands are mostly 2000' or more in elevation so the nights are cool enough for a fire in winter and a relief from the heat of the tropical coast in summer.