The Greywater Guerrillas
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Other Projects

Direct Greywater:

Branched Drain to Bamboo in Berkeley, CA.

Washing machine to large yard in Arcata, CA

Outdoor pedal-powered washer in Oakland, CA.

How to do drip irrigation with greywater.

Constructed Wetlands:

Tiered wetland -- greywater passed through three wetlands, in Austin, TX.

Small wetland to filter shower and grow cattails for use in Oakland, CA

Pretty wetland and wash water in Oakland CA

Bathtub wetlands -- to treat shower water, in Oakland, CA.

Kitchen sink water garden -- in Los Angeles, CA.

Shower water -- another shower system in Seattle, WA with a surge tank.

Composting Toilets:

The prettiest composting toilet in Oakland, CA.

Elevated indoor composting toilet in Oakland, CA

Rainwater Harvesting:

Shower Wetland

Constructed 2005 in Oakland, CA

  • Goals: To reuse the greywater to irrigate several fruit trees and to grow cattails. 
  • Site description: The shower is on the second story, drain pipes were exposed on outside wall, garden is on the adjacent side of the house. The constructed wetland is on the south side of the house and gets a lot of sun and heat in the summer.
  • Fixtures and output: One shower with a low-flow shower head, 2.5 gall/min and built-in shut off (the water is shut off while people soap up), used by 3 people. Usually 2, 5 minute showers a day- 25 gallons per day. 
  • Cost: salvaged tub- $10, pipes and fittings- $30, 2-way valve $25, gravel $10, plants- free.  Most of the pipes were bought used at the salvage yard. Total: $75

Water flow:

The shower drain was cut into on the outside of the house, a ball valve allows water to be transferred to either the city sewer, or the greywater system.

 2-way valve

The greywater pipe is 1 1/2 PVC. It runs along the house and drops 1/4 inch per foot.

pvc pipes

The greywater flows into a milk-crate infiltrator (an upside down milk crate wrapped in 1/4 inch wire mesh). The tub is filled with gravel and larger rock (around the inflow and outflow areas). 

crate-infiltrator

The bathtub is planted with cattails. The water flows through the tub and leaves in the overflow hole on opposite side. Two garden hoses are attached to the overflow.

outflow of wetland, two hoses
One hose irrigates two fruit trees in a flowerpot infiltrator. The other hose fills a 5 gallon container that is carried to the far side of the yard to irrigate other fruit trees.  greywater hose goes into flowerpot infiltrator
  • Specifications and Notes: The cattails use a lot of the irrigation water, especially on hot days. There is no surge tank for the shower because no one takes baths in this bathroom and the long run of pipe holds a significant amount of water. 
  • Maintenance and trouble shooting: Weeding of the wetland. Oxalis likes to grow in it. Carrying the container of filtered greywater to irrigate trees (about every other day).  The ball valve needs to be opened (so the water flows to the sewer) a few times a year to prevent a ball of gunk from building up above it.