Gray Water, Graywater, Grey Water & Greywater Make for Great Water!
It seems there’s a lot of controversy on how you spell the G-word but the one thing that’s for sure experts all agree it can be recycled and reused on the lawn and garden. It was the late 70’s when I first heard of a drought. We had bumper stickers that said “Conserve Water, Shower With a Friend.” As a teenager the idea was phenomenal and all these years later it’s still a great concept but can’t we do something with that water instead of watching go down the drain? Sure! I say “Shower for a Green Lawn” by using graywater (yep, that’s the spelling I’m going with).
All California residences use only 11% of the overall water with a mere 4% in the landscape. When we put on our reality hat on we find that nearly 40,000 whopping gallons of water a year can be diverted from the inside of a house into the lawn and garden. Since that’s the lion’s share of water waste let’s recycle and reuse it for good instead of watching it go down the drain.
Fun Facts….That Aren’t Fun!
Did you know FAKE TURF contributes to global warming, kills soil by cooking and smothering beneficial organisms, isn’t sustainable and can get hotter than asphalt?
What kind of water do I have?
Potable Water: This is the water you’re buying from your water agency. There’s a supply line in the middle of the street which branches off to each house. At the curb, you have a meter that measures the amount of potable water used. When you turn anything on that uses water (ie. kitchen sink, dishwasher, washing machine, bathroom sink, shower, and toilet) you get charged for it. Potable water in all instances is the water we can drink. After that, the water has a name change as we’ll see next.

Filling up a glass of water
Sewer water. Also called “black water” and unless you live at a wastewater treatment facility you have to keep this black water in the sewage system. Black water is always toilet water and we all know what we put in the potty (PU!). Just for tickles let’s put kitchen sink water into this category as well. The reason is meat and meat by-products are typically washed in a kitchen sink for food preparation and cleanup. These elements taint water technically making it black water.
Graywater (soft and hard). This is where we’re going to get our 40,000 gallons of usable landscape water from. Greywater isn’t potable water so don’t drink it! It comes best from the washing machine, bathroom sinks, and showers.
Now that we know what kind of water we have and that graywater is what we need we have to decide if we want soft or hard graywater. Soft graywater is the amount of water you capture before you begin using it. For instance, it takes time for the shower water to heat up and upwards of 4 gallons can be collected. That’s what we call soft graywater. Soft graywater can be captured by putting a 5-gallon bucket under the faucet or showerhead and then turned off when the water is ready to use. If you have some strong pects (pectorals) you can lug the bucket (after getting dressed) to a rain barrel for later use or just dump it on your plants.
Hard graywater would be those four gallons plus the 25+ gallons used whilst taking a shower, washing clothes and using the bathroom sink. But having that many buckets in the shower at one time might be difficult to maneuver around.
Hands down graywater is a great addition or alternative to using potable water but I don’t think it’s fair to sugarcoat the process as you have many choices on how to collect it, what to water and there’s only one way to use it – within 24 hours. What the….????
Pro-Tip: No need to break the bank to get started. Divert graywater to ornamentals (trees, shrubs, ground cover) then water the balance of the yard with potable. The savings will be tremendous.
Bathing, body oils, soap, shampoo, conditioner and hair (yuk), and clothes washing are all elements of what makes graywater, greywater (see what I did there?). Before it begins smelling you have to get it to your plants. Your window of opportunity is within 24 hours of when it’s collected.
Just like you’d have a sprinkler control box you need to plan how to collect and when it’ll be used. If you collect it daily then you might have to water it daily. Or, if you collect it Monday morning by 7 AM and then repeat the routine Tuesday morning you’ll have to use it by 7 AM on Tuesday. That’s double the water but still used within the 24-hour period and ‘technically’ watering every other day – what a loophole, right?. There’s going to be a learning curve but before you know it it’ll be a routine.
How To Collect Graywater
The collection process can be as simple as putting the washer hose into a bucket, rerouting plumbing to a rain barrel or investing in a residential graywater collection system that has filters to collect all the goobery stuff and has a pump to push it through an irrigation system. The thing of it is there isn’t a right nor wrong way of collecting it.
Pro-Tip: Did you know you can water plants collected from an air conditioning unit? AC’s create condensation on the outside of their cooling coils. This condensation is water! A small unit can collect as much as a gallon per day while larger whole house systems can create upwards of 20+ gallons a day!
Cheapskate Me: At around $50 per unit I have 4 each 1/3HP 2450 gallon per hour (GPH) submersible utility water pumps that pump out graywater 1/8” from the surface (two from the baths, one laundry room, and the other outside in a 100-gallon decorative rain barrel). When needed the pumps are light enough for Mrs. Things Green to move. You don’t want them in the bath with you otherwise you might have a shocking experience that’ll end up in an acute state of rigor mortise. We put a quick coupler on the pump out to a hose that goes into a 75-gallon rain barrel. From the rain barrel, there’s enough pressure from that pump to water plants and the lawn. This method is by far the most inexpensive way to collect and distribute graywater. Technically all you need is a bucket and a pump.
Modified Plumbing: All your fixtures (sinks, toilets, washing machines and showers/baths) have a p-trap (it’s that figure-S pipe under the sink). It’s there to hold back sewer stink. If you look at the roof of your house you’ll see pipes coming out. Those are the sewer vents. They work with each p-trap venting the smell out. If you’re handy with a pipe wrench or know a plumber, you might want to modify your plumbing with a pipe diverter that is installed downstream from the p-trap. You would then need a diverter graywater pipe that is plumbed outside. You can take it right to the garden or into a cistern.

Plumber fixing white sink pipe with adjustable wrench.
Another way, and most hassle-free, is to do the above and have it go into an automated graywater system that will not only hold the water but filter it out as well. The filters come in different sizes and shapes that have to be cleaned out weekly to every 6 months. Some of these systems also have pumps with enough zip to run drip, soaker hoses, and sprinkler pipes. With many of these units, the graywater is filtered so you can leave it in the holding area for a longer period of time and not be rushed with the 24-hour timeline. Of course, follow all of the manufacturer’s recommendations.
On a side note, you might come across products that say they’ll keep graywater water from smelling. These products are designed to put an oily film on top of the graywater to stop it from smelling so bad, however, when you go to use the graywater it’ll really stink. Remember, it’s best to use graywater within 24 hours.
Nick Federoff
ThingsGreen.com PBS|KLCS TV and Syndicated Radio Garden Expert
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