Graywater
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Graywater is our new way to recycle water in Oregon.
Are you interested in finding a way to reduce the amount of tap water you use to water your landscape or garden?
Read on to learn more about graywater, how it can be used, and how to obtain a graywater permit in Oregon. You can also contact us if you have any graywater questions or are interested in setting up a system.
What is Graywater?
Graywater is water from washing machines, sinks, showers and bathtubs
Graywater is water that contains some soap, but is clean enough to water plants.
Graywater systems can significantly reduce the amount of water you use during the summer to water your garden and landscaping.
- Approximately thirty percent of residential water use in the US is for outdoor watering.
- By reusing the water from a washing machine, shower, sink, or bathtub, the average household could reduce its water usage by 16-40%!
Oregon Graywater Program & FAQ
Have a question about graywater?
Contact Whitney Bailey, Senior Urban Conservationist:
For years it has been legal in Oregon to harvest graywater to be used indoors for toilet flushing.
Oregon’s graywater program (started April 2012) allows us to use graywater for outdoor watering as well.
May be used as a source of graywater:
- Shower
- Bath
- Bathroom sink
- Kitchen sink
- Washing machine
May NOT be used as a source of graywater:
- Toilet water or waste
- Water from a garbage disposal
- Water from a dishwasher
- Water contaminated by soiled diapers
Learn more about using graywater with the FAQ below.
Graywater can be used safely to water lots of plants around your home (using sub-surface irrigation).
- Fruit trees
- Berries
- Vegetable gardens (As long as the graywater does not touch the edible portion of the plant)
- Lawn areas and landscape plants
See this Oregon DEQ Guide for a comprehensive list of plants that can be watered using graywater.
Graywater should not be used in call cases.
- Root crops: Bacteria in the graywater could contaminate root vegetables and make someone sick if they eat them.
- Acid loving plants: Graywater is generally more alkaline than potable water, so some acid loving plants may be damaged by graywater.
- Drought tolerant plants: Established plants that are used to dry conditions may not respond well to new irrigation.
For more information on using graywater for toilet and urinal flushing, see the Water Conservation Systems Oregon Smart Guide
Non-potable use of graywater within a structure for toilet and urinal flushing is regulated under the state plumbing code.
Other states also have good resources and information on graywater systems.
Please note that some of the information from the following websites (permitting, regulations, rainfall patterns, etc.) may not apply to graywater systems in Oregon.
- Washington State Greywater program
- San Francisco Graywater Guide – a detailed guide to graywater from the City of San Francisco
- Greywater Action – a collaborative of educators who teach residents and tradespeople about affordable and simple graywater systems
Get Your Oregon Graywater Permits
Getting a permit for your graywater project.
In Oregon, to use graywater for your garden and landscaping, you’ll need to get a few permits before installing the system at your home.
- Plumbing permit for the local jurisdiction
- Graywater permit from the OR Department of Environmental Quality
For more information on the permitting process, see the OR DEQ Graywater website.
