of rain puts about 600 gallons of water atop a square foot house! That's a lot of free water. These cisterns collect rainwater from a nearby roof and when the tanks are full water is dispersed through a gravity-fed drip system that irrigates crops.
This is great since we don't have any outdoor hose hookups! How to Build a Rain Barrel. A dual barrel system that uses atmospheric pressure to equalize the water volume in both rain barrels. Use the water from your rain barrels to water your plants.
How do I create a complete Rainwater Collection System? The image below shows a complete rainwater collection system. While some of the components shown are absolutely necessary, not all of the components listed are required.