Southern California (and many regions of the world) suffer from water "shortages". Without exploring the economics of that expression (there are no shortages, just prices that are too low...), I want to put in a plug for recycled water, or what others call "toilet to tap" (i.e., cleaning waste water so that it can be used, again, for drinking water.)
In San Diego, the mayor has taken a stupid stand against toilet to tap. Why the "toilet" word? Because people who dislike the idea (Do they work for the bottled water folks?) want you to think the water is "dirty". Here are my thoughts:
1) People in San Diego already drink toilet water. The water they get (from the Colorado River) has already passed through a dozen municipal waste water systems. (seventeen percent of Colorado River water is discharge) Recycling is a cheaper way of extending water supplies.
2) All water supplies are being contaminated by hormones, chemical residues, etc. Recycled water is no different. Bottled water "from municipal sources" (as most is) is also not different.
3) In Prescott, AZ they sold the rights for 2,700 acre-feet of treated waste-water for $67 million. That's about $25,000/acre-foot! (These are annual flows, like a water annuity.)
Bottom Line: We've got to take what we can get as far as water is concerned. We already drink toilet water, and there's no sense in turning away from cheap, local supplies.