13 Effective Plant Based Grey Water Systems
By building your own grey water treatment plant you can save thousands of gallons of water. Recycled grey water can be used to water a garden, do laundry, wash dishes or flush toilets. Combined with a filter it becomes drinkable. Managing your own waste is an important step to self-sufficiency. If an apocalyptic event occurs large waste water treatment plants may shut down.
In nature water is filtered in wetlands. We can mimic the action of a wetland at home by building a reed bed or a living machine to clean water without chemicals. The grey water enters the system and is filtered by the plant roots and sediments in the soil. Here are some simple, effective designs to filter grey water the way nature does it.
1. Young Reed Beds
The most common way to mimic a wetland is to construct a series of reed beds. The reeds grow well in fine gravel or sand. The gravel catches large waste particles in the grey water.
It is best to build the beds on a slope below your house so water can flow naturally through the system. These reed beds are young. As they grow they will be able to handle more volume. After the two reed beds is a bed of cattails, planted in a finer silt, which will remove the last of the residues from the water.
2. Grey Water Grease Trap with Worms
Plant based grey water systems can handle detergent residues, kitchen waste and soaps. But grease is their enemy. Plant roots, even those of water plants, need oxygen. Grease coats the roots and eventually “drowns” them.
You’ll need a grease trap before your reed beds or living machine. This grease trap uses worms to break down oils. The worms feast on the grease and turn it into rich castings for your garden. This particular design is used to treat shower and sink water, which is then fed slowly into a swale where it waters fruit trees and vegetables.
3. Mature Grey Water Treatment System
Not all plant based grey water systems are reed beds. There are many plants that can be used to filter your grey waste. By planting fruit trees and perennial vegetables, you can take advantage of the nutrients present in the water. This is a mature living machine that filters grey water and provides food for the family.
4. Septic System Reed Bed
There are many plants that will filter grey water. Use local wetlands as your model, and source plants that are native to your area. Native plants are hardier and usually the most inexpensive.
If you do your research and plan carefully, you can use a wetland design to filter black water from the septic tank. Black water filtered through a plant system should only be used gardening or in toilets.
5. Natural Swimming Pool
Man-made wetlands can do more than just filter waste water. This natural swimming pool doesn’t require any chlorine or chemicals to stay pristine and clear. All the work is done by wetland plants. And it is a stunningly beautiful addition to your yard.
6. Simple Grey Water Reed Beds
Reed beds can be an aesthetic addition to your yard. These simple grey water treatment beds use a pump to move the waste water through the system. While this set-up is not on a slope, the bottoms of the beds are slanted to move the water through. For a filtration system like this to work properly, it must be well planned. Consider using a professional wetland designer to help you.
7. Reed Bed Around Septic System
This is the foundation of a reed bed that is being constructed around a septic tank. It’s primary function will be to filter grey water that flows directly into the beds, but it is also a back-up that can absorb spilled waste from a septic overflow. Such a design is especially useful in regions with heavy rains, hurricanes or a long wet season.
8. Sidewalk Living Machine
These planters were installed by the San Francisco Public Utilities Commission. All of the building’s waste water flows through them. The purified water is used for landscaping and flushing toilets. Not only are they a pretty addition to the front of the building, they also fight carbon emissions as they purify water.
9. Banana Grey Water System
In tropical climates, banana trees make great additions to a grey water treatment system. They act much like reeds, but they provide tasty fruit as well. It looks like there is some junk in the background, but that is actually a solar powered pump that moves the water through the system.
10. Bathtub Reed Beds for Grey Water Treatment
Reed beds can be as simple as you like. A common design is to use an old bathtub as the foundation of the bed. It is important the bed has an impermeable lining so that the water stays long enough to be filtered. If you don’t use a tub you can line the bed with cement or a heavy duty plastic pond liner.
11. Cold Climate Grey Water Treatment System
This insulated bed was designed to make it through the winter without freezing. It is a simple and small design that handles the waste water from the kitchen sink and two bathrooms. In the wet winter months the water is used to irrigate herbs. Eventually it will be diverted back to the bathroom.
12. Floating Reed Beds
Reed beds can also be built on floating pallets. They are commonly used to clean lakes with water quality issues. A floating reed bed filters storm water runoff and provides habitat for wildlife. This is a portable constructed wetland that is a great option for a community on the water, or even for use in your own pond.
13. Grey Water System with Edible Features
With a little creativity a grey water system can be designed with multiple functions. This plan filters waste from the shower, runs it through reeds and eventually into a deep pond. Tasty water plants like watercress, water celery, arrow root and edible reeds can be planted. They’ll help clean the water and make nice salads. For even more food value, use the filtered water to irrigate fruit trees or grain crops.
Learn More about Treating Grey Water Naturally
Interested in building your own grey water system? Here are some great resources to help you get started.
- Principles of Ecological Design
- Create and Oasis with Grey Water
- The Resilient Farm, Innovative Whole Systems Approach