Grey Water FAQ
(Grey Water Systems – Frequently asked questions)
Grey Water Re-use
1. Where would the Grey Water System be installed?
The grey water system would be installed underground with the water running into the system at the top of the chamber. Water Rhapsody 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 reach. We manifold these pipes to get the grey water to a central location, achieving a fall of between 1 in 40 and 1 in 60.
2. Can the grey water piping be concealed within the walls?
If you are building a new house, then these pipes are easily concealed. Your plumber simply brings all sources of grey water to the position best suited. As far as a retro-fit is concerned, most of the pipes are hidden underground, though it is sometimes preferable to have some of them exposed.
3. What are the implications regarding any toxic levels to the plants or animals in your garden using grey water?
Water Rhapsody has installed more than 3000 grey water systems in Cape Town alone. Your Water Rhapsody franchisee will recommend low or phosphate free washing powders to use in your laundry. Avoid the use of fabric softeners, and sodium hypochlorite (JIK).
Many of the Water Rhapsody installations date back from 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 must go into the sewer.
4. Who provides the grey water pipe work?
Water Rhapsody provides all the pipes required from
* the point of where the grey water pipes lead out of the building,
* to the hose and sprinkler in the garden.
Our system switches on automatically and pumps the water as soon as about 35 litres are accumulated.
5. How much does the grey water system cost?
Prices are subject to a quote, and a fully installed system varies between R7,800 and R11,800 depending on the characteristics of the building.
6. 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 in the sprinkler. An overflow is provided which is connected to the sewer. Materials and travelling are all included in the price.
7. If I have a Fynbos garden, should 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.
8. Can I use my irrigation that I already have with my grey water system?
Water Rhapsody 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.
9. 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 every day.
10. 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.
11. Can I mix the rain and the grey water?
Water Rhapsody will gladly fix a trickle feed from a rain water tank to introduce this water at a slow rate into the Grey Water system.
12. 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 needed to be stored a water purification system must be added to clean the water.
13. How long does the grey water system take to install?
Water Rhapsody will install a Grey Water system in one day and this will be confirmed in the quotation.
14. Does the grey water give off an odour?
Grey water does produce a faint odour while irrigating but, but the odour disappears within seconds after irrigating. Our maintenance instructions which take a few minutes a 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. We therefore have a separate lot of instructions if you go on holiday that will leave you Garden Rhapsody ready for use when you return.
15. We have four bathrooms. Can we use the grey water from all the areas?
Water Rhapsody are specialists in delivering all your grey water from your house to where this water needs to be delivered. If perhaps it is impossible to get all the sources together, there are more tricks up the multiple sleeves of Water Rhapsody and we may even recommend that an additional pump chamber be installed. Never feel that we have not tried our best to harvest all the possible sources of grey water.
16. 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 say ten years of continuous use. So instead, one brand stands out, viz Ecosoft a washing powder (detergent) which is environmentally friendly (and free of phosphates) – making it safe for Fynbos. You may use soda ash, or washing soda that will do just as well to emulsify oils and fats in the laundry.