How to Use Gray Water to Save Money (and Resources)

We use mind-boggling amounts of water. On average, each American uses about 300 gallons of water every day , most of which he uses indoors. Of course, these applications are quite fundamental – we are talking about washing the body , dishes , clothes and the house, not to mention cooking, drinking and heating.

Most of this water is literally thrown into the sewer. The water used for bathing, cooking, and other activities is called gray water (sometimes spelled gray water here in the US), and it is estimated that this gray water makes up about 75% of the water we literally flush down the drain . Even though most of this water is treated and returned to the system, it is still an incredibly wasteful way of managing a precious resource, and since you are paying for the water that is pumped into your home, it is also a waste of your budget. But you can do something about it, because gray water is completely recyclable in many different ways, and it’s not that hard to recover.

Difference between gray and black water

It is important to note that the water you flush down the toilet is not dirty water but black water and should not be used in any way. And the water that runs down your kitchen sink can also be problematic due to its potential grease content. What about everything else in your house? Fair play if you take some precautions.

Local and state laws regarding the use of gray water

Greywater use is regulated in some way in most states, so before you do anything, you should check what laws are in place in your area (you can also check if your homeowners association has graywater regulations). Most states actually encourage the use of greywater, but some have specific guidelines about the types of systems you can set up and how you can use the water, and you may need permits.

Sources of gray water

If you’re average and use 300 damn gallons of water every day, you should be able to recover a significant amount of water for other uses (you paid for it, after all). Even with the exception of your toilet and kitchen sink, there are many sources of dirty water in your home:

• Washing machines. These are huge sources of water, and they have one huge advantage: they have built-in pumps that are already pumping gray water into your drainage system. All you need to do is connect a bypass valve , which will redirect the water to a more useful place. Whether it’s a complex project or just pumping water into an outdoor bucket, either way you’re recycling a valuable resource. However, one note about dirty water from washing machines: the convenience of using it depends entirely on what you pour into the machine. Washing dirty, poop-soaked diapers means that the water in them is black, not gray, and should not be used. And you have to be careful using biodegradable soap that is harmless to plants .
• Souls and shells. A hot shower is humanity’s greatest achievement, but it’s inherently inefficient. Restoring that gray water is as easy as taking a 5 gallon bucket into the shower to collect that water instead of letting it run down the drain. Once collected, it can be used in any way convenient for you. Similarly, instead of pouring water down the sink drain when you do the dishes, use a smaller bucket to collect the water.
• Different water. Anything in your home that uses, collects, or accumulates water can be a source of greywater: air conditioners that need to be drained, water from an old fish tank, water left over from cooking, and so on.

Ways to use gray water

If you carefully use biodegradable soap and other products, the wastewater you collect has a wide range of uses:

• Irrigation. Whether you water your lawn or keep your garden lush, there’s no reason why you can’t use gray water to irrigate your landscape. It can be as simple as bringing a bucket out into the yard and filling your watering cans with it, or setting up a more ambitious laundry-to-garden irrigation system .
• Toilet flush. Do you have a bucket of water after shower? Pour it down the toilet for the next flush. There is no reason why you should use clean drinking water to flush your toilet. In fact, for about $100, you can install a toilet sink that will let you refill the toilet cistern every time you wash your hands or brush your teeth—no bucket required.

One last word of caution: don’t try to store gray water. Since it was used to wash things, it is not completely clean and if left standing, it will become a source of bacteria and other dangerous things. Gray water is perfectly safe at the point of collection and should be used almost immediately.

When you think about it, dumping so much water down the drain without the slightest effort to repurpose it is wild. Luckily, all you need to change the dynamic is a bucket.