Greywater simply refers to water from bath tubs, bathroom sinks, washing machines and showers that have not come in contact with feces. In most parts of the world, kitchen and toilet water is considered black water due to the high bacterial content found in it. Reusing greywater is a legal and common practice all over Australia, New Mexico, Arizona and many other parts of the globe. California alone is estimated to have more than a million users of greywater, and no instances of illnesses as a result of using greywater are yet to be reported.
A reported published by UCLA estimated that 10% of Southern Californians used greywater for toilets, laundry and more, the potable water savings could be equivalent to or more than the capacity of a large, modern seawater desalination plant.
Greywater systems are a small investment that homeowners in various parts of the world can make and reap various benefits including increased water supply, relieving stress on municipal sewer and treatment plants, increasing the fertility of soil and more. The landscape should be designed in a way that allows optimal infiltration while mulch basins provide sites for optimal microbial activity.
Many people often make the mistake of storing greywater to use in existing irrigation systems forgetting that this is far more expensive and complex to set up. A simple system that relies on sheer force of gravity to direct water is just as effective for irrigation, but less costly.
A laundry-to-landscape greywater system can be easily installed in households where the washing machine is placed in a room with an exterior wall. A three way diverter allows homeowners to direct water to the sewer or garden as desired. This is especially important if a homeowner occasionally uses detergents containing chemicals that are too harsh on plants. A homeowner can use as many branches as they need in their branched drain greywater system and use ball valves to control the flow of greywater to specific areas of the yard or garden.
Proper calculation of the budget, which is affected by the amount of greywater that will be discharged as well as the type of system installed, is important. You also need to take into account the amount of greywater that you will need per week and the size of the landscape. The type of plants you irrigate using greywater and the detergents or soaps used matter a lot.