The water supplies for the lagoon run straight from the National Power Company´s bore hole in Bjarnarflag. The water has a temperature of about 130°C when it gets there so before running into the lagoon it is cooled down in a so-called heat exchanger. The water then runs through a 1 km long underground pipe driven by steam power. Before it enters the lagoon it runs into a huge basin beside the lagoon itself forming an impressive, man-made hot spring.
Altogether, the lagoon and the basin contain around 3.5 million litres of water with a temperature of 36 – 40°C.
The lagoon itself is a man-made construction, its bottom is covered by sand and gravel.
The characteristics of this water are unique in many ways. It contains a large amount of minerals, is alkaline and well suited for bathing.
Due to its chemical composition, undesired bacteria and vegetation do not thrive in the lagoon making chloride or any other disinfectant redundant.