Now that Captain Kirk is using Kickstarter to build a water pipeline to California from someplace with "too much" water, I was thinking about what would be cheap ways to get large amounts of desalinated water. One suggestion (Popular Mechanics??) from my childhood: towing an iceberg (assuming we can still find one) to San Diego/Long Beach/San Francisco harbor and harvest it into the water supply. So long as you don't care much about speed, moving stuff through water can be quite energy-efficient. So even if it took a number of weeks to move a large iceberg, the percent lost to melting would be relatively small. Furthermore, if you wanted to reduce the melting, you could wrap the iceberg in bubble-wrap to better insulate it. Another option would be to wrap the iceberg in plastic wrap to catch the melted (desalinated) water & pipe it into a nearby oil tanker. You could presumably use an oil tanker itself to bring fresh water from someplace with "too much", and this would likely be energetically cheaper than using a pipeline, but such a tanker could carry only perhaps 80% (by volume) of the amount of oil it would normally carry. If you were forced to desalinate the seawater locally, it would be best if you could use solar power to do it. Solar panels are becoming cheap enough that they might allow relatively inexpensive desalinators. Even better, solar panels are _distributed power_, so it makes sense to build small, modular desalinators -- perhaps the size of a standard shipping crate. If you made these modules so that they were waterproof & floated, you could hook them together into a floating desalinization plant which required no expensive space on the California coast. Furthermore, if you provided a long enough hose, you could put these (very low profile) modular solar desalinization plants over the horizon so that they wouldn't mess up the view from expensive California real estate (this is a real problem with offshore wind farms). Putting the desal plant far out in the ocean also solves another problem: what to do with the discharge water with higher salt content. If you discharge this close to shore, it messes up the local sea life, whereas if you do it far out to sea, it can get diluted much more in the deeper waters.