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Irrigation with Graywater Conserves Water and Money

 You’ve installed water efficient fixtures and appliances in your home, and converted all or most of your landscape to drought tolerant plants.  What more can you do to be a good water-conserving citizen?
California has adopted a new residential graywater code that can help you save money on your water bill, and relieve summer stress on our over-stretched drinking water supplies. Graywater is “wastewater” from clothes washing machines (sans dirty diapers), bathtubs, showers, bathroom sinks, but does not include wastewater from kitchen sinks, dishwashers or toilets.

Graywater provides multiple benefits.   The most obvious is the water savings. Graywater accounts for about one-half of the water that goes down the drain from a home, or 10-15 thousand gallons from May-October for a family of four.  Graywater reuse means money savings by having to purchase less water. Significant amounts of energy are saved from pumping less water from our streams and aquifers, and from not having to send the wastewater to the water treatment facility.  Sending less wastewater to the treatment facility translates into chemical and energy savings from not having to treat the graywater.  People on septic systems that divert graywater to the landscape benefit from having less septic loading, thus extending the life of their septic systems.

The California graywater code requires construction permits for graywater systems that alter the drain/vent plumbing system of a home, but exempts laundry-to -landscape irrigation systems from requiring a permit if 12 best management practices are met. It is very important that graywater systems be properly designed, installed and maintained by an experienced professional so that graywater has no contact with people and pets, has no cross connection with the potable water supply, does not mix with stormwater flowing into waterways, and doesn’t pond and create habitat for mosquitoes.
The Central Coast Graywater Alliance is currently seeking motivated homeowners who would like to replace their existing irrigation with a graywater system as part of a Green Gardener Graywater Training Program.  Residences selected to take part in the training installations will be asked to pay a modest materials fee and all permit costs, but will receive free labor from landscaping and plumbing professionals enrolled in the training program. 

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