From hemenway@jeffnet.org Sun May 9 22:43:38 1999 Date: Sun, 9 May 1999 10:55:05 -0700 From: Toby Hemenway Reply-To: permaculture To: permaculture Subject: [permaculture] re: grey water filtration Stephan Leimroth wrote: >i'm looking for ideas for a grey water filtration system adequate enough >to handle at most >120 gallons (450 l) per week. Stephen: A gravel and sand filter won't remove the dissolved contaminants (soaps, etc), but only the hair and other solids. You really need living elements to process the organic and inorganic compounds dissolved in the greywater. I'd recommend a wood-chip filled mulch basin that feeds some plants, or a planted bog. A very simple system is just a 20- or 55-gallon drum that empties (all at once via a siphon, if possible) into a heavily mulched bed around some trees. If the outlet is a hose, you can move the outlet every few days to a new bed. Greywater is not very unsanitary unless it's been stored for a few days; then nasty bacteria build up, so you don't want a big holding tank. Usually it can just go right onto a pile of mulch or some other absorbant. Art Ludwig has a lot of great information at his website, http://home.sprynet.com/sprynet/odesign/home.html, and you might want to get his books before proceeding. I wouldn't recommend trying to make drinking water; that requires about 4 layers of treatment and if something fails, you could get very sick (the treatment could make the water worse if it's not running right). But John Todd's work on Living Machines will show you some fine ideas in that direction, if you want to track that down. The Permaculture Activist (http://sunsite.unc.edu/pc-activist) has good articles on greywater systems and constructed wetlands in issues 37 and 32, respectively. Good luck! Toby Hemenway --- You are currently subscribed to permaculture as: london@metalab.unc.edu To unsubscribe send a blank email to leave-permaculture-75156P@franklin.oit.unc.edu