This is not related to skiing, but assuming there is less snow overall, it seems there is a point where will need to "generate" snow anyway to store water for spring/summer, this is probably still cheaper that building dam/reserve everywhere.
Dams don't use energy once they're built. Hydropower is renewable and carbon-free.
Furthermore, if you're making snow to store water, you can't control when it melts, and you need to collect the water as it melts, most likely behind some kind of a dam!
" “We were surprised to find that the biological productivity of the reservoir (i.e. how many 'nutrients' like nitrogen and phosphorus the reservoir receives and the associated degree of algae growth) is a better predictor of emissions than is latitude. So, the most biologically productive reservoirs are producing the most methane,” writes Bridget Deemer, the study’s first author "