Laundry to Landscape Grey Water Completed

Continuing on from my earlier post, our L2L garden project is complete and I can’t wait to do the laundry! The Grey water experts, aka Grey Water Corps, installed the system in less than 5 hours with remarkable skill and a good measure of aesthetic awareness. While the project was a  low-tech plumbing operation the crew made sure that all the elbow joints were tight and sound and that all the pipes were unobtrusive and blended with the stucco color and wood tones of the walls and steps.

Step 1:

 The washing machine waste water pipe was modified so that the waste grey water could be diverted for garden use. This was achieved by connecting a new plastic pipe to the existing pipe and channeling it downwards and through a small hole in the wall to the outside. A directional valve was added that allows the washing machine water to be directed either to the garden or to the sewer line, a useful item for those occasions when you may be using your machine with less plant friendly detergents. As I will be using salt free environmentally friendly detergents the valve will be set to landscape mode.

 The washing machine motor is powerful and will push the water into the connecting pipe and into the outside down pipe where gravity does the rest. There is no need for an additional pump as Greywater Corp’s designed the system utilizing the grade of the garden to make maximum gravity flow.

Step 2:

The pipe from the washing machine having passed through the outside wall was connected to a down pipe which in turn was connected to the new irrigation delivery pipe. Each elbow joint was tightly fitted and firmly glued. The down pipe and connecting elbow joints were painted beige to blend with the stucco wall. The brown irrigation pipe was snugly fitted to the wooden step and then continued on to the outer edge of the garden.

Step 3: 

The rigid brown delivery pipe was then connected to a flexible blue pipe that was buried in the soil and continued around the garden supplying grey water to each mulch basin via a connecting T fixture ( below). See above photo red box shows blue pipe painted brown to blend.

 Step 4 – Step 1 chronologically

 Each designated mulch basin, identified with a purple flag was dug to a depth and width of approximately 18”. A black collar was then installed to house the water valve and create a barrier that will stop excessive mulch and debris from clogging the valve mechanism. The collar sits inside the hole and was partially filled with mulch to conduct water down to the plant roots. The amount of water released is controlled by a simple valve at the end of the T connector. The area around the collar is filled with mulch that helps distribute water to surrounding surface areas by osmosis. Each collar is fitted with a cap that also serves to protect the valve.

 The mulch used by Greywater Corp was fairly chunky so it will break down slowly but will need to be replaced or augmented in about 12 months.  

 Thank you Leigh,Danica,Trent, Russell,Clay and all the great people at Greywater Corps that made this project possible.

Greywater the Experts Way

 If you need a 101 lesson in grey water and the storage of rainwater, then the experts at Greywater Corps (GWC)are where you need to go. We met Leigh Jerrard the founder of Greywater who shared his years of experience and valuable time to analyze and explain what was both feasible and affordable in our quest to use less water. 

 To recap we have maxed out ways to conserve water and are still using 112 gallons a day for 2 people and 2 canines. While we live in the hope of seeing rain, we are experiencing a state drought that shows no sign of abating. We also know that if we do receive rain it may be torrential but brief and not enough to sustain us for more than a few days even if stored.

Greywater is something we create on a daily basis and if carefully managed can be used to replace or supplement our intake of mains water. Living in Hollywood we are actually rewarded by DWP if we can keep our water usage to tier 1 which is charged at much lower rate than tier 2 making this good financial as well as ecological sense.

 Greywater in our home comes from 2 sources, our washing machine and our bathrooms shower, tub, and sink. The bathrooms that we use are located on one side of the house that is close to our front garden. Our laundry room is on the lower level and close to our back garden.

 The plan is to use our grey water to irrigate both front and back gardens and we began by focusing on the plants in the back garden and how to use the grey water from our washing machine.

Back Garden First Area for Greywater

Most of these are well established with minimal water needs but the recently planted Podocarpus and the fruit trees need more water than they are currently receiving.

 Washing Machine Grey Water versus kitchen sink black water

The distinction between these types of water in part depends on where you live and the irrigation codes in place but however defined, all black water is directed to the sewer line. Part of the concern with kitchen sink water is that bacteria and pathogens are created by food particles which are usually not present in washing machine or shower water. Kitchen sink water also contains cooking grease and even though we typically wipe off the excess oil with a paper towel a small residue is left. Unfortunately, oils and fats take a long time to decompose and their accumulated presence in garden soil makes sink water unsuitable for irrigation purposes.

Washing machine water although cleaner than sink water often contains bleach, boron, and salt all of which are harmful to plants.  These are found in consumer detergents and soaps and while their concentration is diluted in wet regions, the aridity of our soil coupled with the drought make these problematic. In California we are spoilt for choice and have plenty of soil friendly cleaning products available to choose from. I am currently looking into a dry sheet washing products as these have the added benefit of reducing our consumption of plastic bottles used to package liquid detergents.

 Low tech use of washing machine grey water

Grey water should not be stored but should be used directly. We do our washing twice a week and plan to use the grey water immediately on those days to irrigate the garden and either suspend using our mains supplied drip system water on those days or significantly reduce the amount we use.

GWC will add a diverter valve behind our top loader washing machine with a manually operated valve which will allow water to be diverted either to the garden or to the sewer. The valve is needed to stop excess watering occurring on those occasions when we receive torrential rain and when there is the risk of too much water spilling onto neighboring gardens. This is a low- tech system that will use the washing machine pump assisted by gravity to push the water downhill through pipes into 6 emitter outlets distributed across our 1,600 s.f. garden. Each of the outlets will distribute greywater to a mulch basin or trench that will be dug into the ground and filled with wood chips that will filter and absorb the greywater and distribute it to the root system of our plants by capillary action. The size of each mulch basin and shape will be designed by GWC according to the size, grouping and type of plants to be supplied by each of the 6 emitter outlets.

This post would not have been possible without the information freely given by the team at Greywater Corps and in particular Leigh Jerrard. Thank you.