What I don't know about water

The alumni magazine for Columbia has a fascinating article about the work being done with water by some of the faculty. Here are some interesting facts:

• We use about 100 gallons of water a day per person. (I find this hard to believe, but consider the toilet, the washers, etc.). But we drink only about a half-gallon a day.
• The essential point made in the article is that we treat all water so that it is drinkable. This is a huge waste of energy.
• Salt water comprises 97% of earth's water. Two-thirds of the remaining water is encased in ice sheets. Our supply of water is a mere 1% of all the water on earth.
• 70% of our water is used by agriculture. The most common form of irrigation used in agriculture is flood irrigation, 15-20% of which will evaporate before use.
• The largest expense in bringing water to California is powering it over the mountains.
• 20% of our water is lost because of faulty piping.

Maybe we need to look at our water problem in a different way.