In time of crisis and under specific conditions, it is safe to use household water in the garden. Guidelines need to be observed and it is a good idea to check with your local health and building officials before you begin. It is not safe to use used dishwasher in the garden. Water collected in buckets in sinks and in the shower as you wait for warm water to arrive is clean wastewater and usually safe for outdoor use. If your home is equipped with soft water, your water contains sodium. Application of sodium to the soil causes it to bind and resist water penetration. If you use clean, softened, household water in the garden, flush soil regularly with clean hose water to counteract salinity or mix gypsum into the soil surface.

Laundry water can be used safely in the garden if you install a washing machine greywater sump. You will need to obtain a permit from the San Luis Obispo County Planning & Building department before you begin. The County has made available to residents a 5-page document describing the use of greywater in the garden and the steps required in building a typical sump, available at http://www.slocounty.ca.gov/Assets/PL/building/Washing+Machine+Greywater+Sump.pdf

Information and required standards regarding using laundry and rinse water in the garden can be obtained from the Department of Water Resources at http://owue.water.ca.gov. The University of California also has information available on “Using Household Waste Water on Plants” #2968 at http://vric.ucdavis.edu/veginfo/topics/fertilizer/Householdwastewater.pdf, or by calling the Master Gardener helpline.

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