The research work done so far has confirmed the presumption that the lake has got a typical ‘vaucluse’ spring that has a steep and deeply sunken siphon shaft that turns back up only at a great depth. Having used 420 m of supporting rope going down the siphon, divers have reached a depth of 160 m below the surface. The emerald green surface of the lake is usually idyllic and peaceful, but only a few days of strong rainfall and the water starts spewing out of the siphon.