Salvatnet

Salsvatnet is a lake in the municipalities of Fosnes and Nærøy in Trøndelag county, Norway. With its deepest depth of 464 metres , it is Norway's and Europe's second-deepest lake, after Hornindalsvatnet. Alternate sources give the depth as either 464 metres or 482 metres at the deepest point. The lake sits very close to the ocean, about 9 metres above sea level at the surface and reaches to a depth of 455 metres below sea level. It is a very large lake with an area of 44.77 square kilometres , a volume of 6.87 cubic kilometres , and a shoreline that is 105.61 kilometres around.
Salsvatnet is a meromictic lake, meaning that the water is permanently stratified, often without oxygen in the lower depths due to density gradient and a lack of turnover. A meromictic lake often preserves records of the geologic past. The lower layer of the lake is highly saline and as a result denser than the higher levels of water. Other meromictic lakes in Norway with old seawater in the lower depths include Kilevann, Tronstadvann, Botnvatnet, Rørhopvatnet, and Rørholtfjorden.

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