Greywater 101


Survival Podcast intern Josiah Wallingford has started up a blog, Brink of Freedom, that I’m going to contribute to periodically. In my first post, Laundry to Landscape: How to Reuse Laundry Greywater, I discuss my own greywater system as well as the setup I installed at neighbor Lora’s house. Greywater has been one of the simplest and most rewarding projects at our homestead. And I’m looking forward to continuing the conversation over at the Brink of Freedom.

Netafim Tiran, a Greywater Dripline

In a lecture I heard recently, Leigh Jerrard of the Greywater Corp mentioned an intriguing product from Australia: a dripline compatible with greywater. Now, if you tried to push gunky greywater through conventional dripline it would clog in seconds. According to the manufacturer, Netafim Tiran Greywater Dripline gets around this problem because,

Each dripper has its own mini filter. When a contaminant attempts to enter the emmitter, it is rejected by the emitter and simply remains in the tube. The irrigation system should be flushed once a year, however anecdotal evidence indicates that flushing may only be required every 5 years.

100 meters of Netafim costs 100 Australian dollars excluding tax, or about .30 USD a foot. Not a bad price if it performs as advertised. Some quick Googling failed to turn up a US distributor. Root Simple reader Rachel wrote to point out Netafim’s distributor locatoer:

To use Netafim you need to add a filter as you do with every drip system. I could see this product working nicely with Art Ludwig’s Laundry to Landscape system.

If any of you have worked with Netafim, leave a comment.

Dry Farming

Jethro Tull–the agriculturalist not the rock flutist

According to a 2010 report by Ceres “Water Risk in the Municipal Bond Market,” Los Angeles ranks number one in water supply risk. But we’re not alone. Many other US cities including Atlanta, Phoenix and Dallas also face a future of water insecurity.

Due to these water risks we’d all do well to consider ways to grow edibles without supplemental irrigation. This may sound absurd at first, but I’ll note that in our garden we’ve discovered, quite by accident, that many plants such as prickly pear cactus, cherry tomatoes, cardoon and pomegranates will do just fine in a climate where it doesn’t rain for six months out of the year.  Scott Kleinrock at the Huntington Ranch proved that you can grow chard in Southern California with almost no irrigation through a hot summer (the chard thrived in the Ranch’s food forest under almost complete shade).

As an avid gardener in a dry climate I certainly use a lot of water for my vegetables. Most modern vegetables are adapted to copious watering. But this was not always the case. A classic book Dry Farming by John Andreas Widtsoe, first published in 1911 and available as a free download in Google Books, describes how many farmers got along without the modern conveniences of supplemental irrigation.

A dry farmed wheat and alfalfa field in Wyoming from Dry Farming

Other than the advice to till frequently (tilling, among other things, destroys beneficial fungal networks), Dry Farming has some good tips:

  • Maintain soil fertility 
  • Plant deeply
  • Plant varieties adapted to dry farming
  • Know when to plant
  • Pay attention to soil structure

The main takeaway for us home gardeners will be the development of drought tolerant veggies. Native Seed Search is a good start, but seed saving will be the ultimate solution. We’re simply going to have to breed drought tolerance back into our water hungry vegetables. Combined with passive water collection techniques such as sunken rather than raised beds, those of us in arid climates can grow a surprising amount of food with a lot less water.

Clarification: dry farming is not growing during the rainy season (which is called “rainfed agriculture”). Dry farming uses strategies to store water in the soil during the rainy season and then grow during the dry part of the year. Though controversial, dry farming traditionally involves tilling.  It also requires much greater spacing of plants. For more information see the website of the California Agricultural Water Stewardship Initiative.

Pot o’ Goodness: Low, Low-Tech Water Conservation

Mrs. Homegrown here:

Continuing on the greywater theme, on big cooking days, when I’m doing a lot of boiling, steaming, soaking and rinsing, I collect all that used water in a big pot and take it out to the garden to water the plants. It’s full of nutrients, and won’t cause any blackwater* problems as long as you:

  • Use it immediately. It will turn foul if left to sit too long.
  • Pour it straight into the soil–don’t splash it all over edible leaves. Remember, soil purifies water.
  • Don’t use water full of food chunks or grease, as this will attract vermin and cause smells.

I know it’s only a little bit water that I’m saving by doing this, but to me it’s a symbolic act, almost a prayer. And heck, it hasn’t rained here since March, so every bit counts. Also, the plants really like the super-water. I think of it as a smoothie for them.

Another option is to re-use cooking waters as stock. This is something I don’t know much about. Sometimes I’ll take some nice bright green water leftover from steaming or blanching greens and use that to start a vegetable stock. But I’ve heard of people using pasta water as the base of soups. Have any of you tried that, or other techniques along those lines? Do tell.

And let us know if you have any quirky ways of saving water.

*What’s blackwater? It’s water which is dirtier than greywater, and therefore not usually recycled. Typically this is water coming from the toilet and the kitchen sink. Food particles from the sink turn septic quickly, and grease and heavy soap are not good for soil. However, our greywater guru, Art Ludwig, does say that kitchen sink water is nutrient rich, and suggests workarounds that allow sink water re-use, like grease traps or plumbing the sink so only the rinse water goes to the garden.

Greywater Fed Tomato Plant Takes Over The World

Homegrown Neighbor Here:

So a few months ago Mr. Homegrown helped me install a simple ‘laundry to landscape’ greywater system. Most of the plants that get watered by the system didn’t get much water before and were just barely surviving. There are several fruit trees, a rhubarb plant and an assortment of perennial herbs lining a narrow strip of land along the side of the house. Now, the plants getting fed by the greywater are going bonkers.

Last week the area became impassable it was so overgrown. The path along the side of the house had disappeared. I have the laundry water going to the sewer half the time because I don’t want to overwater. That and my roommate bought some non-greywater friendly soap. So I really only run one or two loads of laundry a week into the yard. But that has been more than enough.

Yesterday I hacked my way through the overgrowth and tried to train the rampant cherry tomato plant. The tomatoes are delicious. I eat them constantly when I’m in the yard and pawn them off on friends and family whenever I can. Still, there are tomatoes in areas that I can no longer get too. The tomato plant has killed my apple tree I think. I can’t see the apple tree under it anymore. The tomato plant is about eight feet tall and equally wide. It is reaching for the roof, using the poor buried apple tree as its support. I tried to photograph the madness, but it just looks like an indeterminable tangle and doesn’t really show what is going on.

But now I have reclaimed a path along the side of the house. If just an occasional load of laundry can provide such a boost to this little patch of land, I wonder what all of the other water used in the house could do. I would have to get rid of all of the low-water and native plantings and go tropical! It just goes to show how much water we use in our homes every day and don’t really think about where it goes. Eventually I would love for all of the water from our showers and sinks to go to the yard as well, but for now, the washing machine is creating a little tropical oasis and that’s plenty.