Wednesday, August 15, 2012

My Greywater System

My homesteading guru and mentor Anna suggested that I write a post about my greywater system.

First, two terms:
Greywater: wastewater generated from domestic activities like bathing, doing dishes, laundry, and so on.
Blackwater:  wastewater contaminated with human waste- sewage

Seven years ago, when we built our house, we made the decision not to put in a septic tank. The main reasons were because of possible well contamination and because our lot is quite small. We instead decided to use a composting toilet (which means no blackwater) and a greywater system.

I bought Art Ludwig's book Build an Oasis with Greywater and made dozens of plans, each more complicated and involved than the last. I decided to build an artificial wetland from the house, meandering along a path to a sink near our mailbox. On paper it was beautiful. The gentle curves, the water plants poking up from the pebbles that would make up the system. It would have baffles to keep the water from just running straight, and the plants would clean the greywater gently, using up the excess nutrients as it slowly moved down to the pool.

That never happened. Time constraints kept me from finishing quickly, and we ended up with a small pool of fetid water that smelled like rotten eggs. And it was my fault. I should have followed Art's guidelines, and I should have realized just how much work it entailed to build such a paradise. Moving cubic meters of rocky soil, ordering cubic meters of different grades of rock, not to mention the maintenance cleaning out lint sludge, small food particles that escaped the sink drain screens...

Now I am happy to say that for the second attempt, I followed the guidelines in the book, and have discovered the guiding principle of all truly stable engineering projects. K.I.S.S.

Our greywater now drains to a large unlined basin filled with rice hulls and wetland plants that just naturally  found their way there. A number of water tolerant trees and shrubs form a ring around the outer edge. Again, I didn't plant them, I just kept the ones that thrived.
The large pipe from the house takes all the water to this, and it is wonderful. And simple.
No more smell, no more clogging, when the rice hulls eventually decompose, I just add more.