Greywater recycling

Year-round greywater reuse in cold climates can be a challenge. What to do with all that water when the garden's under snow? Will greywater freeze in the pipes? Many greywater users divert greywater to a sewer or septic system during the cold season, but it's possible to ecologically dispose of greywater even in the dead of winter.

Assembling a woodchip biofilter to trap grease and food particles.Greywater from the kitchen sink contains grease and food particles, which can cause clogging and slow infiltration into the soil. After years of sometimes foul-smelling experimentation, greywater pioneers have concluded that the best way to trap grease and food particles and create habitat for decomposers is with woodchips in a mulch basin, not in a woodchip biofilter.

Labeled 3-way valveIt's easy to follow the guidelines required for a no-permit system from the new California plumbing code. The system needs to have a way to switch back to the sewer/septic, not have any pooling of greywater, be discharged under 2 inches of mulch, and a few more basic guidelines.

labled 3-wayThe pipes from the shower were exposed in an unfinished wall. A 3-way diverter valve is installed and takes greywater outside, to irrigate fruit trees and vines.

Irrigating a veggie bedThis duplex uses the laundry water from each washing machine to irrigate the back yard. Two raised beds receive greywater growing crops with the edible portion above the ground.

Greywatered yardThe water from a shower goes outside to two separate irrigation zones. An electronic switch controls the 3-way valve under the house. Greywater irrigates six young fruit trees in the front yard.