What is graywater (also spelled “greywater”) and why do we find this stuff so interesting? First, a definition from Wikipedia:

“Greywater gets its name from its cloudy appearance and from its status as being between fresh, potable water (known as “white water”) and sewage water (“black water”). In a household context, greywater is the leftover water from baths, showers, hand basins and washing machines only. Some definitions of greywater include water from the kitchen sink. Any water containing human waste is considered black water.”

What makes us pay attention to graywater is that it is made of… water. Any place as dry as Texas is today (and was in 2011) needs to be paying attention to water and to water supply. Our interest in graywater lies in the possibilities that, when properly applied and understood, graywater can ease the demand we place on all our water supplies, from aquifers and rivers to rainfall and ponds and rainwater cisterns. If water is life, surely there is a place and time to utilize graywater’s full potential.

We believe that time is now. Here.

Glenrose publications and resources

Memorandum to Austin City Council External Stakeholders’ Working Group Gray Water Recommendations

Austin seeks to rewrite gray water rules as conservation measure
A Glenrose Engineering staff engineer created a graywater pilot project inside Austin’s city limits, the first to be permitted by the City of Austin.

Other resources

Greywater Harvesting from Brad Lancaster’s Harvesting Rainwater for Drylands and Beyond web site

Greywater Action

Government of New South Wales, Australia, on Greywater

Oasis Design’s Grey Water guidelines and helpful how-to

Government of City of Tucson, Arizona (U.S.) greywater page,,20565323,00.html Video depicts simple “laundry to landscape” gray water system in San Francisco. Go to “Scene Selection” 3 for the portion on graywater.