I would like to use graywater for my 150-year-old brownstone in New Jersey. Is it feasible to use the old cistern?

Asked by David Sporkin
Jersey City, NJ

When redoing the backyard I came across the old cistern that supplied the drinking water for the building before the days of indoor plumbing. I have installed solar panels on the brownstone, so use of electricity for running the pump should not have a negative effect as far as carbon emissions. To resupply the cistern I would use rainwater from the building by diverting into the cistern. Is this practical? Are there people who are actually knowledgeable about doing this?


Polly Osborne, FAIA, LEED AP

Answered by Polly Osborne, FAIA, LEED AP

Los Angeles, CA

Polly Osborne Architects

April 26, 2010

First of all, there is a big difference between salvaged water (captured rainwater) and graywater (wastewater from sinks and washers).

  • Salvaged water is much cleaner. You could use the cistern for that. 
  • Graywater cannot be stored, or you are in danger of it turning into blackwater, which is very dangerous. It contains bacteria from bits of skin and such. 

If you use graywater, you must use it right away, and in a manner whereby it doesn't spray, such as an underground watering system.


For more information:

Read Lee Hall's Q&A "What is the healthiest option when choosing a rainwater tank?"

Tagged In: healthy water, water saving, greywater

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