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The City of Portland, Oregon

Planning and Sustainability

Innovation. Collaboration. Practical Solutions.

Phone: 503-823-7700

Curbside Hotline: 503-823-7202

1900 SW 4th Ave, Suite 7100, Portland, OR 97201

More Contact Info

Green Building FAQ

Graywater (also Gray water, Greywater and Grey water)


In Oregon, graywater includes drain-water from utility, bath and kitchen sinks (not the garbage disposal), showers/tubs and clothes washers (excluding water that has been in contact with soiled diapers). Drain-water from dishwashers and toilets (black water) is not included. Interior use of graywater (toilet flushing) has been legal in Oregon since 2008.

Exterior use became legal in Oregon in 2011, with Department of Environmental Quality (DEQ) permit applications beginning in spring 2012. There are three permit tiers. Most residential systems will fall under Tier I – less than 300 gallons/day with a physical filtering process and sub-surface irrigation only. The next two tiers are for larger gray water volumes, above surface irrigation and include chemical and disinfectant processes. Fees are significantly higher. Local jurisdiction plumbing permits are required. This DEQ PDF has more answers.


Rainwater Harvesting and Stormwater Management

On these sites you’ll find information on stormwater features, grants and rebate programs, as well as technical assistance.

City of Portland

Bureau of Environmental Services (BES)  

Clackamas County

Water Environment Services (WES)  
Clackamas County Soil and Water Conservation District (CCSWCD)

Multnomah County

East Multnomah Soil and Water Conservation District (EMSWCD)
West Multnomah Soil and Water Conservation District (WMSWCD)

Washington County

Clean Water Services
Tualatin Valley Water District (TVWD)