Laundry to Landscape 2.0

I just installed a “laundry to landscape” greywater system at the house of Lora “Homegrown Neighbor” Hall using greywater guru Art Ludwig’s free open-source plans. It was a cinch. And, thanks to a revision in the California plumbing code last year, it’s legal with no permit required.

I started in the laundry room by rigging up a three way diverter valve so that Lora can route the greywater back to the sewer if it’s been raining too much or if she’s bleaching her Prada (not likey, by the way). The diverter, somewhat of an exotic plumbing part, was ordered off of Ludwig’s website. At $47 it was the most expensive part of the system, but it’s well built.

Next, I rigged up two check valves, essentially a one-way gate, one to prevent greywater from siphoning back into the washing machine and another to act as a vent. You could also just use a six foot section of pipe as a vent, but Lora’s overhanging roof made that impossible.

The most labor intensive part of the process was digging the trench for the pipe out in the garden. Lora decided how many outlets she wanted in the garden and we consulted the “calculator” on Ludwig’s site (more of a chart than a calculator, actually, since he’s done the math for you). The calculator basically gives a range of outlet sizes and numbers so that you can get an even flow to the outlets but not risk burning out the washing machine’s pump. With nine outlets Ludwig suggests a 3/8-inch hole. We simply drilled 3/8-inch holes in the bottom of the PVC pipe that we ran out into the garden. The outlets flow into mini-mulch basins along the side of some perennial shrubs and a few small fruit trees.

Altogether it took just a few hours. Lora ran a load of clothes immediately and it worked perfectly. It was one of the easiest home improvement projects I’ve done. No cursing whatsoever! Now Lora can’t wait to do the laundry. She, of course, uses only Oasis Biocompatible Laundry Detergent. Note that many “eco” detergents will kill terrestrial plants–I’ll do a blog post on this shortly, as I discovered one major manufacturer claiming that a detergent was safe for greywater only to discover that it contained several different sodium compounds, definitely bad for soil!

Ludwig gives both a version of this project in PVC and another in HDPE plastic. I chose to work with the politically incorrect PVC since I couldn’t find the groovier 1-inch HDPE in less than 300 foot rolls. If any of you know of a source where you can get 1-inch HDPE by the foot, please let me know in the comments.

If you’d like to do this yourself the plans are all on Ludwigs site under Laundry to Landscape. In addition to the plans there is a parts list for both the PVC and HDPE versions and the aforementioned calculator.  If you don’t think you can do it yourself (remember it’s easy!) you could conceivably hand the plans to a handyman. A plumber would be too expensive, in my opinion.

See also Ludwig’s book The New Create an Oasis with Greywater.

Share this post

Leave a comment

13 Comments

  1. Simply,

    Ludwig has instructions for cold climates. He says to keep the line sloping downhill so it doesn’t hold water. You could also use flexible HDPE and disassemble it for the winter. We’re in zone 10 where it doesn’t rain for 6 to 7 months so greywater probably makes more sense for us than for where you are.

  2. Awesome accomplishment and I’m glad to read about the revision to the CA plumbing code in your post–and another perk–no permit required!

    My husband rigged up a hose (pre-code) from our washing machine to our yard, but it would be a lot more effective if the water were piped into to a drip system like you’ve done.

    I like that brand of detergent you mentioned. I can’t buy it anymore where I shop. Lifetree’s Original Premium Laundry Liquid is great for washing too, but I don’t know if it’s harmful to plants or not–so have just been watering the blackberries with it. I look forward to your post about the ingredients that will harm the plants.

  3. Kristen:

    Just a note to tide you over until Erik posts about detergents. Basically the problem with most eco detergents is that they are formulated to go to the sea via the sewage system and do no harm to the sea. Therefore they don’t have phosphates and other nasties, but they do tend to be salt heavy. Salt builds up in soil over time, and that’s a bad thing. You’ve heard about salting the earth, right? I don’t know where you live. Here in LA, where it rarely rains, our soils are naturally salty because there’s not enough rain to dilute natural salt build up. This makes adding salt to the soil particularly dangerous–but I don’t know if it’s a good idea anywhere.

    Basically,look at your detergent label and seek out any mention of sodium or other natural mineral salts, like borax (borate variants). Again, we’ll post about this and hopefully be able to offer a “danger list” –but from what I know at this point, no eco detergent fits the bill for greywater unless it specifically says its formulated for greywater. And as far as we know, that means Oasis. Soapnuts are also okay for greywater, too, it seems.

    If anyone has other recs, we’d love to hear them!

  4. We hope to do this next summer. Are you irrigating your landscape plants, or can you do edibles too? Our edibles are integrated with our ornamentals.

  5. Kristen,

    I took a glance at the ingredients of the Lifetree detergent and it looked ok from a greywater perspective, but I’ve got to take another look when I have some more time. Just make sure that hose is 1-inch.

    Oaklanda,

    We’re using the greywater to irrigate fruit trees and a few ornamentals.

  6. Do you know if soap is okay? I have some old fashioned lye and lard soap (made for a living history demo) that works really great on dishes and thought of trying it for laundry but the recipes I have seen all have borax, baking soda and or washing soda. I don’t have a greywater system but sometimes do hand washing outside so it would be great to have definitive info on the safest cleaners.

  7. I just bought a lovely wildish Home.
    I will “grey water” it. All these comments and your original post will be my guide. Thank you taking the time!
    i am glad ya’ll did!
    Cheers for Vancouver Island

  8. I’m going crazy trying to figure out how to make a system that will work for me. We’re renting, so we can’t cut holes in the garage wall or make any other plumbing alterations. the washing machine is located on the worst possible end of the house – far, far away from the majority of the gardening. I have to figure out a way to make a movable water barrel, but even then I’ll have to wheel it through a labyrinth with two poorly-designed gates. I need a different house…

  9. The Jandy Never-Lube valve can be an economical alternative to the one listed; I’ve used it on several greywater projects with great results. It’s less expensive than the one listed, you can get it in many different sizes (have a couple installed on whole house systems @ 4″), and it can be taken apart easily if it’s ever necessary.

  10. Hi all, I read your post with interest – it’s a combination of greywater and arid-condition gardening. The query re the practicality of the system in -40degrees could be answered using raised beds (I recall readig an article on a Canadian woman who built two parallel timber walls about 1m high and filled it with garden and kitchen vegetable refuse, and ran her perforated greywater hose through it at about 400mm deep. The veggies she grew on that were gigantic. Otherwise a heavy layer of mulch as an insulator may work… Just a note re the diagram showing a shallow basin about the upended flower pot – in clay soils this could be bad for root systems that find themselves submerged and drowning. We’ve lived on a succession of clay and impervious subsoil land-lots and we just run a flexible hose from the washing machine outlet to the garden and move it periodically…

Leave a Reply

Your email address will not be published.


2 + = 5