Laundry to Landscape Greywater System Management

Bay Maples Infographic

When people talk about greywater, a Laundry to Landscape (L2L) system is typically the first thing that comes to mind. Using the pump and the water from the washing machine, irrigating the garden is simple. A three-way valve is placed above the washing machine. The outflow from the washing machine is directed into the three-way valve. From there, the outflow can be directed either to the sewer or to the landscape. Whereas most of the time the water would be used for irrigating, on those days when bleach or something harmful to plants is used, the valve is turned and water is diverted from the garden. Also, when there is an abundance of water from rain, again, the water can be sent to the sewer.

Older model washing machines can use up to forty gallons of water per load. Newer, front loading models, use around seventeen gallons per load. For a family of four, there can be a savings of 70 to 120 gallons of water per week. To give you an idea, that would be the recommended amount of water for 10 to 20 small or 4 to 8 medium sized fruit trees.

We can install an L2L system, including the irrigation to existing plants and trees, in one day. If you want to use your laundry water but don’t have an existing garden, we can help you design and install the optimal garden for an L2L system.

FAQ’s from L2L

Frequently Asked Questions

You can use anything that is biodegradable and avoid products made with boron or salts. Ecos and Trader Joe’s are two brands that we often recommend. However, there are many brands out there that fit the bill. The main instruction is using a liquid soap as opposed to powdered detergents. Powders tend to be full of salts, which, over time will build up in the soil killing anything that is trying to grow there. And boron. Boraxo, should not be used due to the acidity.

We recommend not sending the water any further than 50 feet away from the unit. Also, you don’t really want to pump the water up hill. If the irrigation run is too long, the pump will get over taxed as it tries to empty the drum. Or, you might see that the drum does not empty entirely. That being said, Bay Maples has stayed with-in the 50 foot guide line and in six years, we’ve never heard of a problem.

You should never store greywater for more than twenty-four hours. Because of the organics in the water, it begins to foul quite quickly. The beauty of an L2L is that you are taking advantage of the washing machines’ pump to assist in the irrigation. Were you to store the water, you would need a second pump to distribute the water later. Better to set up mulch basins and irrigate at the end of each cycle.

If your washing machine is upstairs, it is often difficult to plumb it so that the water can be used. However, if it is on an exterior wall, and you don’t mine a pipe run down the side of the wall, it can be done. The way that the three-way valve system works, it allows us to continue to the stand pipe for waste and direct the irrigation out of the house. Just a little more conspicuously than with a downstairs unit.

As long as you are using a biodegradable soap, no. We have no problem with our soil and we’ve been running our system for over two years. Further, look back here in mid-December. We are just completing a soil study with a student from Cal State San Jose on the effects of greywater, L2L in particular, on the soil. We hope to have her results or the paper up on our site.

Here in Santa Clara County, the Santa Clara Valley Water District provides a Graywater Laundry to Landscape Rebate for properly connecting a clothes washer to a simple graywater irrigation system. Apply before proceeding on any project as rebates are not provided retroactively: Funding is limited and provided on a first come, first served basis. CLICK HERE