Greywater system in New York State

Working with regulating agencies such as the health department or code enforcement can go a long way towards making a person feel frustrated and powerless.  Every alternative, earth-friendly building element we’ve tried to incorporate into the house has been met with some version of “well I’m not really familiar with that so you’re going to need to get an engineer to design it.”  When we found an engineer interested in designing a greywater system for us he wanted $1200.  That would be in addition to the couple thousand we would need to spend to get a health department approved composting toilet and the material cost for the grey water system.  We’ve priced out installing a septic tank and sand filter system and it comes in at around $1600 altogether (with us doing the work of course). 

Once again we are forced to compromise our dreams of a galactica rivaling efficiency (remember when Xena toured galactica?…super rad) and opt for more traditional techniques.  These are the times when the little fascist in me says, “yes, there are people who would willingly or unwittingly build poor structures and pollute ground water, but we’re not those people so don’t apply the rules to us, just to them.”  Oh well, I’m sure we’ll still divert some of our greywater to mulch basins that contain peach and pear trees after we get the final inspection, don’t tell.

In any case, here are some things I’ve learned about greywater systems:

• Mulch basins seem to be easiest. Run schedule 40 PVC from the greywater sources in your house about ten to fifteen feet out, branch them to however many mulch basins you have and then run the branched lines into the mulch basins.  The basin itself is a hole, filled with mulch, with a tree planted in the center.  Your grey water pipe should enter the basin about two inches below the surface of the mulch and at least six inches from the bottom.  Cover the end of the pipe with something like an upside down plastic planter that you've cut to slide over the pipe.  This will help to keep the pipe from getting clogged, though I think probably a screen will help, but be careful not to let large food scraps down the sink or you would inevitably clog the screen.

• Greywater is best used to water trees, which require a great deal of water,       some more than others so research before purchasing.  Fruit and nut trees in particular help to put that water towards food production. 
• Don’t use grey water in a garden. Greywater shouldn’t come into direct contact with anything you would eat.  You may be told that grey water cannot be used to irrigate any food sources, including fruit trees.  From everything I’ve read this is untrue and really underestimates the work of trees at filtering out the many nasty things we put in their ecosystems.
• Greywater should not be stored or allowed to pool at all, after 24 hours it will become black water and will need to be treated as such.
• Switch to natural, non-toxic cleaning and laundry supplies.  If you’re reading this you probably already have but just in case, toxic cleaning supplies would be very harmful to your mulch basin system and all of the other things to which “toxic” is harmful.

Check out San Francisco’s greywater manual for detailed information, but keep in mind the climate of San Francisco allows for smaller mulch basin systems than areas that would be less sunny and/or rainier.

San Francisco's greywater manual

This is another great resource for greywater info:

Laura Allen Greywater Action