[geoschmo]

The reason the article mentions reverse osmosis is that that is a technology that has historically been over-hyped my marketing folks trying to make a buck off gullible people. The basis for RO is a real functioning technology. It's being used in many coastal areas where fresh water supplies are scarce and therefore very expensive. But it's often billed as some sort of magical technology that turns seawater into drinking water at little or no cost and with little or no negative impact on the environment.

In fact RO desalination is an expensive process. Much more so then simply pumping fresh water out of a natural aquifer. Of course in areas where natural aquifers are unavailable, or insufficent for the population level, the cost of alternative methods of filtration, or conventional fresh water transportation eventually reaches a point where RO becomes economically feasible.

There is also some significant evidence that RO can have some pretty drastic environmental impact. Raising the salt levels of the water in the coastal area immedietly around the desalination plant can have effects that we don't really understand yet. Recent studies indicate the problem might be worse then we thought.

It's a proven tech though, and despite it's flaws is crucial in some circumstances. It's just not the magic pill some have made it out to be.