80,000 years ago, the Isle Crémieu region was covered in a layer of ice reaching a thickness of hundreds of metres. It probably looked like Alaska does today. The Isère glacier remained here for tens of thousands of years before disappearing only 15,000 years ago.
The glacier resculpted the landscape, hollowing it out and leaving behind various deposits. As the glacier melted, the basins became impermeable and turned into lakes, which gradually filled in over several thousand years to form vast wetlands and peat bogs.
Save Lake is a relic of those post-glacier lakes. Its morphology, with a depth of 15 metres and abrup banks, is typical of the work of a glacier. This lake will also fill in eventually, as the peatland banks gradually encroach upon its surface area.
The timescale of this phenomon goes way beyond that of the life of humans; it will take about 15,000 years for the lake to be transformed into marshland!
Today, Save Lake is home to an incredible biodiversity. It is particularly abundant in Eurasian beavers and European pond turtles!
Office du Tourisme Les Balcons du Dauphiné - 21/07/2020
Free of charge.