Laundry-to-Landscape Greywater System
The laundry-to-landscape system is a simple system with easy distribution of greywater to multiple plants. It is relatively low cost, and easy to install. The washing machine’s internal pump slightly pressurizes the greywater, so this system can irrigate plants across a flat yard.
The washer hose is connected to a 3-way valve that can divert greywater either to the sewer or the greywater system and piped outside with 1” rigid pipe, like PVC. This system requires 1″ diameter tubing/pipe- larger diameter tubing will decrease the pressure and make it harder to spread out the water; and smaller diameter tubing will add too much strain on the pump. Outside 1″ HDPE (high density polyethylene, black plastic tubing) is connected to the rigid pipe and “barbed” Tee fittings split the flow and allow greywater to spread out and water many plants.
Thank you to Art Ludwig for developing the L2L system. Please credit him (as well as Greywater Action) if you use info from this webpage on your own.)
- Watch an Ask This Old House episode on how to build one.
- Watch an excerpt from an instructional video from Oasis Design, the originators of the system.
- See pictures from a real system.
- Download this step-by-step instructional manual on how to build this system from the San Francisco Public Utility Commission’s manual.
• Legal to install without a permit (in several states, like California) so long as state guidelines are followed.
•Greywater can travel slightly uphill (think small bumps in your yard) or longer distances across flat yards.
• Accessible 3-way valve makes it easy to switch between the greywater system and the sewer/septic.
•Very little maintenance.
*Very little digging required.
•Easy to spread out water and reach many plants (up to 20 with a top-loading machine, up to 8 with a front-loading machine, up to 10 with a top-efficient machine)
•Flexible- Easy to change after installation
• Involves some very minor plumbing rerouting.
•If poorly designed the system could add strain on washer pump and potentially shorten its life.
•Some parts not readily available and must be ordered.
Kits available from Clean Water Components or Gray-2-Green
•1″ brass three-way valve
• 1″ PVC pipe and fittings
•”auto vent” or check valve used for air gap
•If yard is higher than washer, use a swing check valve
•1″ HDPE (high density polyethylene plastic) tubing and barbed fittings
• Ball valves (1/2″, used optionally)
1″ barbed fittings and tubing are not available in most stores. You can mail order from CleanWater Components.com or try a large irrigation supply store. In urban areas you can often find the brand Blu-Lock or EcoLock in 1 inch. In areas with agriculture or vineyards, it’s possible to find the 1″ tubing in 100′ sections at a local farm or irrigation store. In the SF Bay Area the Urban Farmer Store sells all the materials, in Los Angeles Aqua-Flo Irrigation carries all the parts.
Cost: $150-$300 in materials. Labor costs vary, but typically add a between $500-$2,000 to the materials depending on the size and complexity of the system.
To maximize the life of your pump avoid pumping greywater more than a few feet above the rim of the washer. If you are sending greywater long distances over flat ground the friction in the pipe will add some resistance on the pump. A safe rule of thumb distance is 50 feet of horizontal pipe.