Instead of desalination, purify wastewater. Up where I live, our water comes from the lake and goes back into the lake. In between the input and output is a was

Instead of desalination, purify wastewater. Up where I live, our water comes from the lake and goes back into the lake. In between the input and output is a wastewater treatment plant that emits water so clean that you can drink directly from the outflow pipe.