Before hitting the ground, most of the rain hits a treetop. Then it descends at different times, infiltrates the soil and supplies the groundwater. The eminent lack of water on the planet is actually a distribution of this natural resource. Rainwater that falls on the roof drains superficially across the floor in the house. This runoff will hit some body of water and it will also carry with it the top soil, which is the richest in nutrients. Rainwater does not infiltrate, it impoverishes the soil and clogs the water veins.
All of us are still going to live in houses and roofed buildings for a long time. To mitigate the problem, we can use a system that captures rainwater and stores it in reservoirs. That is, a house to be considered ecological needs to compensate the area of soil that waterproofed in its construction. The water accumulated in the own reservoirs is used for the discharge, irrigation of gardens, washing of balconies, cars, clothes, floors, among others. In some cases, it can even be used for bathing.

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