By Larraine Roulston:
Grey water is retrieved from showering, doing dishes or washing clothes. (It is not water that has come in contact with dirty diapers or toilet water). Capturing this household resource is a great way to recycle water for your garden. The type of detergent and household cleaners you use, however, should be phosphate free. By utilizing grey water, you also will save money on your water bill.
Although grey water will contain bits of food, grease, dirt or soaps, it is safe and beneficial to plants and grass since its nutrients are a valuable fertilizer. Reusing grey water also diverts it from the septic or sewer systems, where these nutrients become pollutants in our rivers and lakes. Irrigating with grey water reconnects residential gardens to the natural water cycle.
With a grey water system, your garden can remain green, even during times of restricted municipal water usage. You are simply diverting the water directly from your shower or laundry through a system that will filter it for your garden’s plants. There is no need to retrofit your plumbing or install any system underground. Using gravity keeps your method simple and low-tech, and avoids the necessity of installing pumps and filters that require maintenance.
To be safe with grey water, you have to be mindful of the following:
- Do not allow pets or children to drink the grey water.
- Avoid spraying grey water into the air, as you would by watering with fresh water from a hose; rather, use a subsurface distribution method such as drippers beneath a layer of mulch.
- Do not to let the grey water touch the edible part of the plants in a vegetable garden.
- Avoid using washing products that contain salts, boron or chlorine bleach, as the build-up of these can eventually damage plants.
- Do not to store unused grey water longer than 24 hours if you use a holding tank.
- Do not let holding tanks build up with sludge. Keep their filters clean and free of lint.
The washing machine is noted as the easiest source of reusable grey water because it can be diverted without cutting into your existing plumbing. Washing machines have an internal pump that can be used to send the grey water directly to plants. A laundry drum can also be strapped to a wall to collect wash water. An attached hose can direct the water for efficient irrigation purposes. The water from showers is relatively clean. On the other hand, kitchen sink water is not only high in organic matter but also has a lower volume output and may not be allowed under some states’ grey water codes.
Every system is unique and can be implemented by doing sufficient research. The branched drain system, for example, is installed on a sloped landscape to have water flow through a 1 1/2” drainage pipe, where a plumbing fitting divides the flow of water into smaller quantities. Alternatively, you can simply catch clear cold tap water while waiting for it to warm. Both can be used to “bucket flush” a toilet or to water plants. Either way, you will be conserving a precious resource.
- Greywater friendly products
- Plants and greywater
- Laundry-to-landscape greywater system
- How to conduct a simple percolation test
- Manufactured greywater systems
- Commercial scale greywater systems
- Greywater systems in freezing climates
- Constructed wetland information
- Examples of greywater systems
- Greywater resource page
Larraine authors children’s adventure books on composting. Visit www.castlecompost.com