Here's a good site.

Here is a link that might be useful: rainwater harvesting

our family lived in Viet Nam before we came to tx, we collect rain water for drinking only, rain water is the best clean source of water that we can have. usually, the first couple rains in the season are have lots of polution in them and we don't collect until mid season. however, the best time to collect rain water is in winter and during a second day of continuos rain. we collect and store water in a large 55-70gal clay barrel. the clay barrel actualy do a good job of keep the water clean and cool. don't be alarm when you see mosquitos and things live on the bottom of the containers, they are harmless creatures no matter what you do, you can never get rid of them, just make sure that you don't swallow them.
i remember when my grand still alive, she put a pumkin in to a full rain water clay-barrel (rain water only!)and seal the lid up. the pumkin start to rotten in there for years by the time she reopen the pumkin remain is just some settlement on the bottom of the barrel. she said that the pumkin help reduce axiety and purify the water, it also help to boot up the immune system, the recipe has been passing through generations in our family and unfotunate there are no clay-barrel here so i can't keep the recipe going!

How interesting! We will be retiring to new mexico, and hope to have a cistern system installed. Just another area to look into for inexpensive filtration, lol.....Cheri

We are building a new house and it is becoming more common to use rainwater as an alternative to wells. We had the choice and decided to do rainwater for our house. This isnt cheap (17K for 20,000 gallon tanks & UV filters, pump, etc) but the well would be almost the same costs. With all the new construction in our area, many wells are going dry so this seems like the best solution. During droughts, water can be brought out on a truck (+-$50 for 5,000 gallons). The water is filtered off the roof (we are having metal roof), the 1st wash is stored in a separate container for landscape watering then the rest is stored in 2 tanks. Tanks have a UV filter. No need for water softners because the water is really soft and clean. The company putting our system in even sells bottled rainwater at groceries around here. Our county also offers dollar for dollar reduction on property taxes for any expense related to building the system (roof, gutters, etc). I would be interested in hearing from anyone who has this kind of system, but our research shows it is well liked.

most of the smaller inhabited islands of the Bahamas have been using cisterns for their water source for a long time

Hi, I'm writing about my house in the French Alps. Previously, we had a spring there for a water source but it seems to have dried up. We had a drought two years ago and a fairly dry summer after that. This summers also promises a drought. We are looking for more springs, but in the meantime, I am wondering how to start an underground watertank to keep water for the dry months. If anybody has information on that, I would be obliged. I'm also interested in mountain plants that would be drought resistant. I already have some lavendar and thyme. Thanks for your input.

"most of the smaller inhabited islands of the Bahamas have been using cisterns for their water source for a long time"

I grew up in upper Eastern Tennessee and cisterns were very common. My family used a cistern until I started high school in 1967. My dad treated it with Clorox and added a little alumn to coagulate loose particles. We had a lever that would divert the rain water to the cisten and had no problems.

Eventually the city ran a line up the mountain to a doctor who lived up the road from us so we tapped into it and covered the cistern. The only difference between the two was the rain water was free and the city charged.