Future water supply is an important issue, and while I do not agree that cutting leaks by 15% goes far enough, I would consider that water metering to be a far bigger problem.  My supply is metered, but I am led to believe that this is not considered the norm "down here".  The truth is that I am subsiding unmetered consumers, who continue their "laissez faire" mentalities when they should be required to pay for what they use.
It would also greatly aid yourselves in ascertaining exactly how much water is lost through leaks.