Here in Reno, Nevada, we get under 7" of rain per year. Can we collect enough rain water in a rain barrel or barrels to make a dent in the average 136,000 gallons per year that a metered user like our household uses? Admittedly about 70 per cent of the yard is lawn--around 3000 square feet of it.
Annual rainfall here in San Jose, California, is about 15", distributed fairly evenly. I can't tell from my water bill what percentage of water use (and expense) is for household use versus landscaping, but my son's science project says a California family of four like ours uses a whopping 174,000 gallons per year! Our typical mixed landscaping covers about 3500 square feet. What percentage of my water utility costs and usage might be for landscaping?