The Blue Lagoon geothermal spa, one of the most visited attractions in Iceland, is located in a lava field about 24 miles southwest of Reykjavík. Its warm waters, which average around 100°F, are rich in minerals like silica and sulfur and bathing in them is reputed to help treat some skin diseases. Several cosmetics companies have even begun marketing skin care products using mud purportedly extracted from the lagoon.
The lagoon, which is actually man-made, is fed by the water output of the nearby geothermal power plant and is renewed every two days. Superheated water is vented from the ground near a lava flow and used to run turbines that generate electricity. After going through the turbines, the steam and hot water passes through a heat exchanger to provide heat for a municipal water heating system. Then the water is fed into the lagoon for recreational and medicinal users to bathe in.
Because of its mineral concentration, the water cannot be recycled and must be disposed of in the nearby landscape, a permeable lava field. The silicate minerals is the primary cause of that water’s milky blue shade. After the minerals have formed a deposit, the water reinfiltrates the ground, but the deposit renders it impermeable over time, necessitating the plant to continuously dig new ponds in the nearby lava field.
- Visited: July 2012