We have been harvesting rain water for years now. Every time it rains it's like pennies for heaven. This is the best water you can get, the best and it's free! There is a tremendous amount of water running off your roof, thousands of gallons. Collecting can be as easy as a bucket or trash can along your roof line. With gutters you can direct the flow into a tank or cistern. If your tank is high enough off the ground you can plumb it and it will gravity flow to your yard or garden when needed. If you live in town rain collection should be a must. The run off over taxes the sewer systems, picks up the oil off the streets and becomes some really nasty stuff. If you collect it you've got free pure rainwater for your yard or garden. Some towns and cities have even installed rain barrels so they didn't have to build bigger waste water treatment plants. It is a greener solution. This is a must,it's one of the neatest things I've learned from harvesting rainwater, to kill mosquitoes without chemicals or expense, put some feeder gold fish in your tank or cistern. You'll never have to feed them, they will live off the bugs and mosquito larvae. They can also be a good indicator of the water quality, kind like the canary in the coal mine. We get enough water to grow all our organic food, flowers, and rare plants this way. You could purify this water slap a label on it and sell it for a dollar a bottle. Which some very happy folks do, since it's a free resource. The large cistern I built out of concrete, and inlaid with mosaics, petrified coral, jade, and have screened it to keep the leaves out of the water. It took some time to do, but will last longer than I will. The large plastic tanks are great, you want to get the opaque black ones which will keep the light out and will reduce algae. If you bury them you will have to pump, above ground you can have the gravity flow water. The up front costs are barrels, tanks, and plumbing. The returns are free pure water and the satisfaction of harnessing the rain. One of the best projects you can do with the highest return. All life needs water. _________________ Simple Solutions for Complex Problems. There is Nothing Common about Common Sense.