According to this article in le Progress
Rather than let snow melt they are keeping it in storage over the summer and reusing it in the winter. A report from the French Government says that 250MW/h are used to make snow in France in a season so this could be quite an energy saving.
The Fédération française de ski (FFS) is behind the scheme which has run at Mijoux in the Jura. During January 7000m3 of snow was made by the snow guns of the national cross country ski center. The snow was stored from April on top of tree bark on top of wood chips to absorb melting snow. In July only 20% of the stock had melted, despite record temperatures.
With the first frosts of autumn the snow is being used to cover a 1.5km of cross country ski runs at les Tuffes. The French national team will soon be using this snow for training.
Apparently this has already been done in 2000 in Finaland where the technique has been called “snow farming”. Next step is to stock snow from the roads and parking spaces. Of course none of this snow is returned to the water table, given the current drought conditions in the Northern Alps this could have an impact on the water cycle. The snow also takes a lot of labour to spread out on the runs.