What is greywater? As the human population continues to grow, the pressure being placed upon the world’s natural resources is intensifying, and that most precious commodity of all, water, is already feeling the pinch. Even in the United States, where living standards dictate easy access to water and plumbing in nearly every community, water can sometimes be a scarcity, particularly in the booming metropolitan regions of the West and Southwest, where water service companies face constant difficulties in securing adequate water for their massive populations.
Because features of modern life such as toilets, showers and irrigated landscapes are unlikely to go away, scientific- and environmentally-minded individuals have given thought to the ways in which we can reduce the overall consumption of water, even as the number of households in the United States is increasing. One of the most promising is the use of “greywater”.
Greywater is the waste water generated when we undertake some of the most common household tasks: taking a shower, washing the clothes, or even washing the dishes. Greywater is named as such to distinguish it from “whitewater”, which is the clean, potable water piped into the home; and “blackwater”, which is sewage taken from the bathroom via the sewer lines. Greywater, therefore, stands somewhere in-between: it isn’t clean enough to be potable or to be used again for washing, but it is not as toxic as blackwater, and may have applications in the home where it would serve just as well as the more valuable whitewater.
One of the most common uses for greywater is for landscape irrigation. Homes with greywater irrigation systems have to be conscious at all times of the soaps and cleaners that they use in their home, as all chemicals in the water end up in the landscape, and some chemicals can be fatal to plant and soil life. Greywater irrigation is typically relegated to non-edible gardens and landscape, and is distributed via sub-soil or top-soil dripping systems, in order to limit the exposure of possible pathogens to the air. As an alternative to irrigation, some homes have systems that treat and re-process greywater for use as toilet flushing water, getting two uses out of the initial whitewater that is brought into the home.
Another innovative use for greywater is the temporary diversion of the water (which, by nature of what it was initially used for, is typically warm) through a heat-exchanger that surrounds the pipes in which cold water is carried to a water heater. The cold water (which never mingles with the greywater) is thereby pre-warmed by the greywater, saving on the energy costs involved in a home’s water-heating cost. Some hotels in large cities even time their laundry with the morning shower routines of their guests, taking advantage of the huge amount of hot and warm water used in their wash to pre-heat the shower water!
Because greywater does tend to contain some pathogens, its use requires careful consideration both by individual households considering installing a system, and by government entities tasked with enforcing standards of health and safety. Many jurisdictions ban the use of greywater outright, while others permit greywater systems as long as they adhere to certain accepted plumbing codes. In all cases, it is vitally important to put in place a proper system that can adequately monitor, treat and distribute greywater, without compromising the health of the household, or the community at large.
See also:
Greywater Recycling
Green Homes
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Water is very essential to us but we don’t actually realize the need for conserving water. By small and simple means we can save water. There are so many ways in doing it and this post is actually the best way of doing it. It will help the whole community too.
I was thinking about this the other day… At least it should go to sprinklers to water plants.
Prior to this read, I had no idea about the ‘Greywater’ concept. It is obviously a novel way to conserve and reuse water in a useful manner. It is quite astonishing just to imagine how much water we can conserve when we have a bath and while washing clothes/utensils.
I think grey water is a good idea, if it saves the planet..
I’ve read that some are not considering water from doing the dishes as grey water since the water will likely contain organic materials and fats.
“Many jurisdictions ban the use of greywater outright”
Im a bit surprised the government/water service companies are not offerig grants or insentives. I agree it is putting a lot of trust in the houshold, with regard to what is in the greywater. but if they have paid or the installation, I would have thought they would be vigilant.
I never heard this Greywater recycling idea before but it sounds useful to me. We are definitely wasting our natural resources blatantly. We must preserve them for our next generations but coming up with eco-friendly solutions. Thanks for sharing the idea, i will share this post with people i know.