Grey Water FAQ

While the previous two sections covered the basic ‘black’ and ‘white’ of Grey Water, you probably still have more questions. Below is a list of the questions we get asked most frequently, but if your question or concern is not covered here, please contact us, we’d love to help you out.

• Where would the Grey Water System be installed ?
  The grey water system would be installed underground (near to and accesible from the surface) with the water running into the system at the top of the chamber. Water Solutions would therefore install the grey water pump chamber at a point where even the lowest (usually the shower) of the pipes from the bathrooms and laundry can flow into the Garden Rhapsody.  We manifold these pipes to get the grey water to a central location, achieving a fall of between 1 in 40m and 1 in 60m.

• Can the grey water piping be concealed within the walls ?
  If you’re building a new house, then these pipes are easily concealed. Your plumber simply brings all sources of grey water to the position best suited for the installation of the Garden Rhapsody. As far as installation in an existing home is concerned, most of the pipes are hidden underground, but it is often preferable to have some of them exposed.

• What are the implications regarding any toxic levels to the plants or animals in your garden using grey water?
  The Garden Rhapsody has been installed in more than 3000 homes and locations in Cape Town alone.  Water Solutions (a Water Rhapsody franchisee) can recommend both low and phosphate free washing powders to use in your laundry removing fears of damage to plants or animals in your garden.  You must however avoid the use of fabric softeners, and sodium hypochlorite (JIK).
  Many of the Water Rhapsody installations date back to 1994, including those of the people who started the Fresh Water Institute at UCT, and Professor Kader and Louise Asmal.  They have Fynbos gardens, and these are all green and beautiful.
  We never take water from dishwashing machines, so the abrasive nature of the dishwashing detergent is not of concern. All dishwashing water is concidered black water and must go into the sewer for treatment.

• Who provides the grey water pipe work ?
  Water Solutions provides all the pipes and materials required for the installation of the Garden Rhapsody from the point where the grey water pipes lead out of the building. This includes the hose and sprinkler in the garden. For the record, our system switches on automatically and pumps the water flowing through these pipes as soon as about 35 litres of grey water is accumulated.

• How much does a grey water system cost ?
  Prices are subject to a quote as the size and characteristics of each building and therefore the installation are different. Typically, a fully installed Garden Rhapsody system costs around R8 000.00 What must be noted when concidering this cost, is that the Garden Rhapsody not only saves you water, but money as well. On average, our Garden Rhapsody will pay for itself in 18 to 24 months.

• What do I get for my hard earned money ?
  We supply and fix the manifold of pipes leading from the building, to the filter device.  The filter consists of two nylon devices that never need to be replaced. The water runs by gravity to the pump chamber, which houses the pump. The pumped water is driven into a drive pipe, which becomes a dedicated hose (or hoses) and this terminates with a sprinkler. An overflow is provided which is connected to the sewer.  Materials and travelling are all included in the price.

• I have a Fynbos garden, can I use grey water ?
  Provided that you adhere to the rules of what to use in your house, grey water is good quality water for Fynbos.  However you could combine this with our unique rainwater harvesting and storage system, and use a combination of grey water and stored rainwater through our Grand Opus System.

• Can I use grey water in my existing irrigation system ?
  Water Solutions will provide you with a drive pipe 25 mm in diameter piped around the edge of the garden and attach 20 mm garden hoses with hose fittings and Gardena sprinklers. We never pump grey water into POPUPS or Microjets. Even with advanced filtering the system will soon clog, in a matter of weeks or even days. The Garden Rhapsody pump provides enough flow to produce a six meter diameter spay from 2 Gardena sprinklers, spraying simultaneously.

• Do I have to move a hose around all the time with my grey water system ?
  We supply one or multiple hoses and sprinklers, spread around the garden.  Our pump is strong enough to pump through 2 Gardena sprinklers simultaneously, covering up to 60 square metres of area of your garden at once.  Large gardens would require the hoses to be moved, but there is no need to move the hose and sprinkler more often than once a day.

• What size pump does the grey water system use ?
  Our standard system comes with a small but very robust pump with an open impeller. One size of pump chamber fits all applications, and will even take a small block of flats. For larger blocks of flats, we batch the flats into for example four flats per Grey Water system. If there is a possibility that more grey water will be delivered to the unit with which the small pump can cope, we quote for and supply a pump with a higher delivery and multiple hoses and sprinklers. In this way, there is never any chance of wasting the grey water via the overflow to the sewer.

• Can I mix the harvested rainwater and grey water ?
  Water Solutions will gladly fix a trickle feed from a rain water tank to introduce this water at a slow rate into the Garden Rhapsody grey water system.

• Can I store the grey water in a larger tank ?
  The very first rule of grey water is that you may not store it.  We pump it immediately to water your garden. If grey water needs to be stored a water purification system must be added to clean the water. See Rules of grey water for the reasoning.

• How long does the grey water system take to install ?
  Water Solutions will typically install a grey water system in one day, but installation time is dependant on the job, and this will be confirmed in the quotation.

• Does the grey water give off an odour ?
  Grey water does sometimes produce a faint odour while irrigating, but the odour disappears within seconds after irrigation is complete. Our maintenance instructions, which take just a few minutes each week, will ensure that your grey water system will be odourless. If you leave the pump off for a long period of time, there will be some anaerobic activity.  To combat this we have a separate set of instructions for when you go on holiday (or have to turn the system off) that will leave your Garden Rhapsody ready for use upon your return.

• We have four bathrooms.  Can we use the grey water from all the areas ?
  Water Solutions are specialists in delivering all your grey water from your house, to where it is needed. If perhaps it is impossible to get all the sources together, there are more tricks up our multiple sleeves and we may even recommend that an additional pump chamber be installed. You will never feel that we have not tried our utmost to harvest all your sources of grey water.

• Is the grey water bad for the garden? What detergents should I use ?
  No, provided that our instructions are followed regarding detergent agents, grey water isn’t bad for your garden.  Most detergents contain by weight up to one third pure phosphates which will build up in the soil, and be toxic over about TEN YEARS of continuous use. So instead we recommend a washing powder (detergent) which is environmentally friendly (and free of phosphates) – making it safe for not only standard gardens, but Fynbos ones as well. You may also use soda ash, or washing soda, that will do just as well to emulsify oils and fats in the laundry.

Back to… Grey Water Home

On to… 1 – What is grey water ?

On to… 2 – Rules of Grey Water