The article talks up the market-based solution devised in Australia.  While in theory I'm pretty skeptical of market-based solutions to environmental problems, in theory I could imagine how it would work.  Markets, when they function, can encourage actors to reduce expensive imputs, and encouraging end-users to be more water efficient was the whole point of the system.

However, I find it rather amazing that a few speculators didn't just swoop in and buy all the water, then set monopoly prices.  Australia's water market must be pretty heavily regulated.