Yeah, you're not going to do that without a ton of pumps. I ran the numbers once for a pipeline to the Salton Sea and it looks bad. However, if you built a cana

Yeah, you're not going to do that without a ton of pumps. I ran the numbers once for a pipeline to the Salton Sea and it looks bad. However, if you built a canal (about ten meters wide and the same deep) and flooded the whole Imperial Valley (this isn't popular!), tidal variation would exchange all of the water on average about three times per year. There's an equation for pipe flow rate given a diameter and a pressure difference; the pipe you would need for the Salton is either unrealistically huge or has a really big pump. Hence, canal. I doubt it ever happens, of course, due to all the lost farmland/towns (and the "why bother?" factor). What I was referring to is entirely different: the desalination occurs in Mexico and fresh water is piped around.