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:

Composting Toilet- Remodel

Constructed 2007 in Oakland, CA

  • Goals: To reduce water use and have an ecological toilet.
  • Site description: The backroom of a house was being rebuilt due to rotten beams. The compost toilet was planned out in the remodel. The room is on the first floor with a crawl space and access hatch below the bathroom. 
  • Cost: Urine divering toilet seat- $120, tile- $50 (left over from old project), poop container- $10, urine- salvaged $1, wood - $50. Total cost for toilet: $230 not including labor. 

System description:

The toilet has a urine diverter insert that separates the urine from feces. This dramatically reduces odor from the toilet, and makes the composting process much simpler.  The bathroom is very small so the toilet was built into the corner of the room.  After each deposit, a scoopfull of wood shavings are added (in silver pail). They come from a local woodworker who uses untreated wood. Toilet paper is added to the toilet and composts fully. 

outflow with irrigation line

Below the toilet is a hatch. On the right side is the urine tube, it fills a bucket. The urine is dilluted 3:1 (water to urine) and used to fertilize the garden.

3-way valve

The feces collection bucket is directly below the toilet. The area is sealed off from flies and odor. Note the vent above the bucket. 

feces collection bucket
  • Specifications and Notes: The vent for the toilet travels up to the roof of the house. This is a passive vented system. An electric fan could be added to the system in the future if the need for more ventilation arose.  Everyone has to sit down to use the toilet, if men want to stand to urinate a simple urinal could be installed that sent the urine outside to the urine container. 
  • Maintenance and trouble shooting: The red feces container is emptied twice a month into a larger enclosed feces only compost container. The feces compost in this container for a full year before they are used into the landscape.  The urine bucket is emptied as needed and dilluted with water to fertilize.