I know it sounds crazy, at first glance, but just in the US alone we used something like 20-30 trillion gallons of water/year. If some of that, not just from the US, but around the globe, could come from desalination, and the wastewater was routed such that it wound up in the groundwater, it might have a significant effect restoring groundwater, using up some of the additional ocean water that is predicted, and overall improving quality of life. Haven't done any serious research on this, and am just throwing it out there.
That's all true. Part of the sea level rise is from ground water depletion.