La Save Environmentally Sensitive Area - Save Lake Sector

80,000 years ago, the Isle Crémieu region was covered in a hundreds of meters layer of ice. It probably looked like Alaska does today. The Isère glacier remained here for ten 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 swamps.

The Save Lake is a relic of these post-glacier lakes. Its morphology, with a depth of 15 meters and abrup banks, is typical of the work of a glacier. This lake will 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!