Tufa is actually a carbonate deposit and is formed by a chemical reaction of the alkaline lake water with fresh water springs. The actual process typically takes place underwater and works its way up. Once exposed or close to the water/air interface, abundant flies contribute to the growth of tufa accumulation. During their larvae state, these alkali flies generate calcium carbonate in their glands and then deposit their "secretion" on the submerged towers when they pupate and leave the water as adults. When the lake water receeded, the tufa structures in various forms, shapes and heights become now exposed, towering above the water surface.