Adding greywater to your list of resources in keeping up with water restrictions sounds like an ideal plan. Just make sure you use it for the right purposes. Greywater has many advantages, but it can be a detriment to your health. Danielle Daniëls did some digging on the subject . . .
The average family of four uses between 300 and 350 litres of water per day. Approximately 60% of the water that leaves the home as wastewater is re-usable as greywater and perfect to water gardens, wash cars and flush toilets.
So, adding greywater to your list of resources, especially to keep up with water restrictions – sounds like an ideal plan. Just make sure you use it wisely. Greywater has many advantages, but it can be a detriment to your health.
Greywater is not completely clean and not completely dirty. It’s usually the water that comes from your sinks, bathtubs and showers.
According to JoJo Tanks, a basic greywater harvesting system consists of gravity feeding water to an underground sump (a drum placed in an enclosure with an inspection cover) where it passes through a macro filter to remove hair fluff and lint. The water is then immediately pumped or drip-irrigated into the garden. These simple systems are cheap, cost effective and relatively maintenance free.
An advanced greywater harvesting system is a more sophisticated system that can be designed and installed, which allows the greywater to be stored after it is treated.
Erika Theron, of Rainwater Harvesting and Adri Williams, of Khayelitsha Cookies, shared a little about the different greywater systems.
According to Adri, the cheapest and most affordable system is to guide rain water from your roof directly to the garden, swimming pool or tanks for storage.
“There is a product made of plastic that fits over your existing gutter, with a transparent hose that you can lead to either your garden or swimming pool.
You can also catch the water from your sinks, shower and bathtub with a pump-and-step system.
“Another option is for the plumber to redirect the water to your toilet, which will allow you to flush, using last night’s bathwater.”
Erika said she knows about four different greywater systems.
“The first one would be the basic entry level where the water is not treated at all; it’s a direct system, for example from the shower to the garden. The second system works about the same, but it’s connected to greywater drip irrigation. It makes life easier.
“The third is treated to an extent. This water can be stored and used for irrigation purposes. Any irrigation system can be connected to this water.
“Lastly, the most advanced treatment will give you near usable water. This water is clean and can be used for nearly anything. You just can’t drink it.”
Some systems you can install yourself, while others would require a qualified set of hands. Adri said the special plastic gutter is designed to make it easy for you to attach it at home.
“Various tanks need to be put on a solid surface (a cement or brick slab) to prevent it from being damaged or from falling over. The gutter must run down to the tank at the right angle, so I would recommend getting someone who knows what they’re doing to install it.”
“Some people cannot afford to have the systems installed by a professional and then try to do it themselves, but they are not familiar with the basic rules of what can and can’t be done,” Erika said. “As a result, the system doesn’t function properly. Soon, it starts to smell bad and it gets worse every day.
“Some don’t properly install overflows, which cause puddles to form. This water becomes poisonous.”
The dos
. If the water is not treated then it cannot be left standing or stored; it must be used immediately.
. Rain water can be left standing untreated for long periods of time.
. Greywater from sinks, bathtubs and showers must be treated because it contains the oil and bacteria found on your skin. If you want to use this water in the garden, treat it with vinegar. If you want to use it to flush your toilet, treat it with the chlorine you use for your swimming pool (one teaspoon at a time).
. Remember, always wash your hands thoroughly after handling greywater.
The don’ts
. Never use blackwater – like the water from kitchen sinks. It can make you ill and contains dish- washing liquid that harms plants.
. Untreated recycled greywater is not recommended for vegetable gardens, but if you do use it on your vegetables, remember to rinse them thoroughly before eating them.
. Blackwater must not be mixed with greywater, unless it is being treated as a blackwater recycling system. This water can be used for irrigation, flushing toilets, and so much more. It’s like installing a decent mini wastewater treatment plant at your home, school or office.
