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:

Washing Machine to Large Yard

Constructed 2007 in Arcata, CA

  • Goals: To reuse washwater in the yard and get it out of the sewer.
  • Site description: The washing machine drains into a pipe accessible in the crawl space under the house. The yard slopes steeply away from the house and is planted with ornamental, pollinating attracting plants. 
  • Fixtures and output: One washing machine, top loading. 30 gallons/load. 3 loads per week
  • Cost: Barrel $25 (food grade barrel bought from second-hand lumber yard) Pipes, fittings, and one bag of concrete- $75 Total: $100
  • Designer: Home owner 

Water flow:

The washing machine drains normally (the tube from the machine is inserted into the drain pipe). 


Under the house the washer drain pipe was cut and replumbed outside. A sawzall cut the old rusty steel pipes, no-hub connectors attach to the new ABS pipe. The old line to the sewer was capped off.  (Owner realized belatedly it would have been much easier to run a new pipe into the house, it would just require the right tool to cut a hole up through the floor into the house).  replumbing drain pipes
The new greywater pipe leaves the house to travel to the surge tank. The other pipe in the picture is from the shower greywater system (the white pipe).
greywater pipes leave crawl space









The 40 gallon surge tank is placed under the deck. A small footing of cement was poured over gravel to set the tank on (it is on a slope). The tank was purchased used from a resale lumber yard. It has two bung holes on the top (the threaded holes found on these kind of barrels). surge tank

The greywater pipe flows into the top of the surge tank, entering one of the bung holes. A small nylon sock is placed over the entrance so the greywater flows through it. The sock catches lint and particles and is cleaned out twice month.  (It also could be replaced rather than cleaned if you had lots of extra socks around.)

nylon sock filter

Since the inside of the barrel is inaccessible (the lid doesn't come off) a hole was drilled into the barrel, 1/16 inch smaller then the size of the pipe. Here a 15/16 inch hole was drilled and a 1 inch threaded pipe was screwed into the barrel. A nut and washer hold the pipe in place (on outside of barrel). A threaded coupling  to a reducer to a 2-way hose fitting was used to connect the two hoses.

 outflow with irrigation hoses
A greywatered yard!  The greywatered yard
  • Specifications and Notes: There is no diverter valve in this system. The greywater is always going outside and can't be switched back to the sewer. The designer realized after finishing it that he could have run another pipe into the house and then had the option of placing the washer drain hose into the greywater pipe or the sewer pipe.
  • Maintenance and trouble shooting: Clean the sock filter twice a month and move the greywater hoses around the yard.