'Gray Water' Your Yard

The California Plumbing Code has changed; you can now empty water from your washing machine, sinks, showers and bathtubs into your yard instead of into the sewer.

Maybe you haven't thought of it before. Some people have been waiting years for this to happen.

All around the Bay Area, gray water workshops have been popping up as people try to take advantage of the relaxed regulations, which were adopted on an emergency basis effective Aug. 4, 2009, and were written into the 2010 plumbing code effective Jan. 1.  Hidden Villa recently offered a workshop with Stanford graduate "green-contractor" Roy Nordblom, who explained how to capture and use gray water from washing machines.

Gray water is water that has been used for washing; it excludes toilet water and water used for washing diapers.

Nordblom says the setup for a laundry-to-landscape system is simple, and any good contractor can do it. You don’t even need a building permit to capture your washing machine's gray water. 

The basic plan is to install a three-way valve that gives you the choice of directing the gray water to the sewer or out to a mulch basin that collects the water for surrounding plants.  

The option of running gray water to the sewer is for winter, when you don’t want extra water in your yard, or for when you are washing diapers.

During the summer, you would set the valve to send water to a mulch basin, which you would have created by digging out dirt and filling with mulch. When water goes into the basin, the mulch floats up and the water sinks into the ground, irrigating any plants growing around it.

Some people make a soil island in the middle of the basin and plant a fruit tree. There are many options besides mulched basins for distributing the gray water.

You may have to change your detergent brands and washing habits. Some detergents are not good to use with water that will become irrigation. Most powdered detergents contain a lot of salt. Liquid detergents are better. Ecos detergent is good, as is Dr. Bronner’s castile soap. Borax laundry booster is bad for any sewer system; it kills microorganisms necessary for breaking down the sewage. Bleach? Don't even think about it.

You can find more information at GreyWater Action, as well as ways to conserve, reuse and collect water.  Details about gray water reuse can also be found on the site, as well as installers if you're not into DIY.  John Russell of WaterSprout Landscape Design and Construction has done presentations in Piedmont and San Bruno. 

Wash your clothes and water your yard. Maybe the world is getting smarter.

About This Column: Each week Pam Walatka will explore life in Los Altos Hills. Pam has lived in Los Altos Hills since 1978. In 1968, Pam's organic vegetable garden at Esalen Institute inspired Dick Horan to start the Esalen Orgainic Garden and Farm. Contact Pam at pamwalatka@yahoo.com or visit pamwalatka.com.