Wednesday, April 8, 2015

Fifty shades of gray water

I haven't seen the popular movie or read the book, but I find the topic of gray water far more exciting than the theme of sexual bondage, so I thought I'd use it as a title to get your attention. Since California is in an historic drought, and the Governor is calling for drastic measures to reduce water consumption, we need to be paying more attention to how we can conserve this precious resource. In this posting I'll tell you how to reduce your water by over 50% and save up to 4,000 additional gallons in water through our gardening. And do it cost-effectively!
     Six months ago, we began our experiment to reduce our water usage by installing a gray water system. We hired a local plumber who installed a system that recycles the water from our bathtub, sinks, washing machine, dish washer, etc. (Everything except the toilets!)

The gray water goes through a filter and then to a "French drain" and finally an underground bag full of pea gravel that helps to filter and disperse the water. This system complies with state law, which requires all gray water to be dispersed at least two inches below the surface. Our system uses gravity, not pumps, to bring the water to where it is needed. Around a dozen fruit trees are watered with this system. Because we recycle water for our trees, we are careful to avoid cleaning products with bleach, boron, salt and other toxic chemicals. See

       Our gray water system saves around 10,000-15,000 gallons of water per year. All of this water goes to produce fruit, which further saves water.  For example,  it takes 13 gallons of water to produce a single orange, 3 gallons of water for a tomato, etc. (See below for sources.) These are approximate numbers, of course, but they give you some idea of how much water we can save by growing our own vegetable and fruit using gray water (and a drip water system). Because we produce tomatoes, lettuce and other vegetables, as well as  hundreds of pounds of citrus, grapes,  and avocados, we probably save up to 4,000 gallons of water through our gardening efforts. We also save water by feeding our chickens kitchen scraps: an egg takes at least 36 gallons of water to produce because chickens eat grains that use a lot of water.  (In addition to saving water, growing your own fruit and vegetables saves an enormous amount of fossil fuel, which is used to bring produce to market.)
         Another big water saver was removing our lawn. The City of Pasadena paid us $2 per square foot to remove our turf. We hired a landscaper and he did a beautiful job. Where there was once grass, there is now decomposed granite, brick pathways, and mulch along with native plants. We have actually doubled the size of our gardening area and expect to produce a lot more vegetables this year using drip watering, which is highly efficient.
          How has this affected our water consumption? Our last water bill was 60% lower than the previous year. We expect to cut our water usage in half this year.
          If Californians replace their lawns with fruit trees and water-wise gardens, and recycle their gray water, we could easily reduce our water consumption by 50%. And it's cost effective. In six years we will pay off what it cost us to install the gray water system and the water-wise landscaping. Our new system saves us around $1,000 per year in water bills and gardening expense. And our garden and fruit trees yield us an abundant, money-saving as well as water-saving harvest.

For info about the gray water codes in California, see

If you'd like to know more, please contact us. There are several gray water installers in the LA area, Here's one that popped up in a google search that looks promising. 

How Much Water Does it Take? 

• 2,072 gallons to make four new tires
• 20 gallons of water per glass of beer
• 101 gallons of water to make one pound of wool or cotton
• 2,110 gallons of water for one pair of leather shoes
• 900 gallons of water for one pair of blue jeans
• 36 gallons of water per egg
• 60 gallons of water per serving of corn
• 18 gallons of water per apple
• 3 gallons of water per tomato
• 2.6 gallons of water per sheet of paper
• 37 gallons of water per cup of coffee
• 11 gallons of water per slice of bread
• 32 gallons of water per glass of wine
• 1,083 gallons of water for one cotton shirt
• 468 gallons of water per pound
• 616 gallons of water per 4 oz. hamburger
• 1,232 gallons of water per 8 oz. steak
• 39,090 gallons of water are used to manufacture a new car, including tires

How much water is used during the growing/production of a single orange?
13.8 gallons
How much water is used during the growing/production of a watermelon?
100 gallons
How much water is used during the growing/production of a loaf of bread?
150 gallons
How much water is used during the growing/production of a tomato?
3 gallons
How much water is used during the growing/production of rice?
35 gallons
How much water us used during the production of an egg?
120 gallons

How Much Water Do We use? 

• Taking a bath or shower: average is 9-12 gallons per person
• Americans combined use each day for showers: more than 2.7 billion gallons of water
• Watering the lawn:180 gallons
• Washing dishes by machine: 13-19 gallons
• Washing clothes: 35-50 gallons
• Washing the car: 50 gallons
• Brushing your teeth: 2-5 gallons
• Cooking: 5-10 gallons
• Flushing the toilet (once): 4-7 gallons
• Leaking toilet (per day): 60 gallons 

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