Societies of the past had to deal with this. We still deal with this in wealthy societies actually. When the US west coast is hot and dry, authorities ration wa

Societies of the past had to deal with this. We still deal with this in wealthy societies actually. When the US west coast is hot and dry, authorities ration water usage. I can imagine governements doing a more serious job and limiting more things for the common good (aka we don't kill ourselves by destroying our environment)