Drinking water (also known as "potable water") is water that is safe to drink. Many countries impose strict standards governing the quality and purity of drinking water. A great deal of effort goes into processing, transporting and storing water so as to ensure that people have access to a sufficient quantity of high-quality drinking water. This not only costs money, but also consumes a great deal of energy and untreated water.
Rainwater for everybody
Rainwater can be harvested locally and free of charge in almost any location around the world. It can be used for any domestic purpose which does not require drinking water quality. By using rainwater, the average household can reduce its consumption of drinking water by approximately 50 %. Listed below are some ideal domestic uses for rainwater:
for flushing the toilet, or
Rainwater in the washing machine
Rainwater is inherently soft and free of calcium and magnesium, properties that make it ideal for laundry processes: there is no need to add any water or fabric conditioner - your washing comes out soft and easy to iron. Calcium deposits which make textile fibres feel stiff and rough are a thing of the past. And the washing machine is better protected as well - using rainwater completely eliminates those mineral deposits which lead to higher power consumption and may damage the washing machine.
Using rainwater to do the laundry is hygienically safe provided that the rainwater harvesting system has been professionally planned in accordance with DIN 1989. Some people who suffer from allergies even prefer rainwater because their skin reacts to the chlorine that is often added to mains water as a disinfectant.
Rainwater in the toilet
Thanks to the absence of calcium and magnesium in rainwater, your toilet cistern will no longer be harmed by the problem colloquially termed "limescale". The seal in the cistern remains intact - limescale deposits can damage the seal causing a continuous trickle of water into the toilet pan. Last but not least, by using rainwater, you are refusing to be one of those people who flush perfectly good drinking water down the toilet!
Rainwater for cleaning
If you have a separate, specially labelled tap for filling your mop bucket, you can use rainwater for cleaning and wiping surfaces. You can cut down your use of cleaning agents and your cleaned surfaces will be sparkling and "streak-free" when they are dry.
Structure of a rainwater harvesting system
The following picture shows a family home with rainwater harvesting system. Besides the cistern, it's components are: Rainwater filter, smoothing inlet, floating suction filter and rainwater plant. The clear water is used for toilet flushing, garden irrigation, in the washing machine and for cleaning.