Rainwater Harvesting Rainwater harvesting, or collecting rainwater for future water needs, has been used for many centuries as a way to take advantage of seasonal precipitation that otherwise would be lost to runoff or evaporation. People, like the modern Hopi and O'Odham farmers, as well as ranchers in the Southwest United States, construct dams, terraces, ditches, cisterns and ponds to collect and store rainfall for use on their farms and ranches.
Rainwater harvesting is a major source of drinking water for many people around the world.
The Desert House rainwater system can be divided into two components. First, rainfall that lands on the landscape is diverted to plants via contoured slopes and berms. Plants needing relatively more water are placed to collect more runoff. Basins have been built around particular plants to collect water and allow it to percolate slowly through the soil. This method insures that plants receive the water they need and very little water is wasted.