Grey Water Use

          banana tree garden  
Banana trees in Dominica, West Indies.  Photo taken by PCV Emily Stewart.


What is Grey Water?
Plant Selection
Common Mistakes
Commercial Systems

What is grey water?

Grey water is considered all used water that is discharged from a house, excluding black (toilet) water.  This includes water from shwers, baths, sinks, dishwashers, laundry tubs, and washing machines.

Grey water commonly contains soap, shampoo, toothpaste, food scraps, cooking oils, detergents, and hair.

To learn more about grey water, visit websites:

What are the benefits?


close up of bananas on banana tree

Bananas in Dominica, West Indies.  Photo care of Emily Stewart, Peace Corps Volunteer. 

What plants should you use?

Depending on the climate and soil conditions, certain plants are better adapted for use in grey water treatment schemes.  Here are a few examples of plants that grow well using grey water.  Click here to find more information about each plant, and to select the ideal plants for grey water treatment in your climate zone:

Food Crops and Oil Producers
Mulchable Species

For an excellent database of these and many other plant species, visit the Floridata Encyclopedia.  Scroll to the bottom to search the site.


Common mistakes

Avoid making a system that is too complex for the situation.  If it involves a large amount of maintainence someone must be available to do the work.  Often transporting water by hand instead of pumping it is the best idea.

Grey water should not be stored or it will quickly turn into blackwater.  A maximum amount of time before application to biologically active soil should not exceed 24 hours.

Do not apply grey water directly to any part of a plant that you will eat.  Pathogen contamination is possible.  This is why grey water is best used for fruit trees and ornamental plants.

Some acid-loving plants cannot handle grey water.  Also be careful applying it to plants during the dry season that will not be able to handle the change.

Plants that  should be avoided include: For an extensive list of other common mistakes, visit the following website:

Higher Volume Grey Water Treatment


Website Creators:
Aubrey Frazer                  Emily Owens

MS Candidates in Environmental Engineering at Michigan Technological University
Master's International Peace Corps volunteers in Jamaica and
East Timor

Date created: 15 March 2005
Last updated: 28 April 2005