Water Efficiency
Reuse Gray Water And Rainwater For Irrigation Or Toilet Flushing

What Is It?

Gray water (or “grey” water) is wastewater discharged from domestic activities and appliances, including but not limited to washing machines, sinks, showers, bath tubs, dishwashers, or other sources but not toilets, urinals or any drains equipped with garbage grinders. A gray water system recycles this water for other uses, such as irrigation or toilet flushing.


Using gray water instead of treated, potable water reduces demand from water utilities and thus reduces water bills. Gray water systems ease strain on the public water supply, lower the use and increase the life of sewers and/or treatment systems, and save energy use from pumping and treating water.

  • Read more about the benefits of gray water systems.

Challenge Participants Currently Adopting This Practice

  • CB Richard Ellis, 1 Beacon (link to Project Story)
  • BioMed Realty Trust
  • Boston Properties, Inc.
  • Community Servings
  • KC Real Estate Management
  • Massachusetts Convention Center Authority
  • Save that Stuff

Financing Options, Incentives, And Rebates

Additional Resources

Examples of Gray Water and Rainwater Reuse in the Boston Area:

What you should know about Gray Water Systems in Boston and Massachusetts

A Small Sample of Gray Water Equipment Providers in the Boston Area

In The News